采煤采矿采煤机外文文献翻译、中英文翻译、外文翻译
关于采煤煤炭方面的外文翻译、中英文翻译、外文文献翻译
附录AProfile : Coal is China's main energy in the country's total primary energy accounted for 76% and above. Most coal strata formed and restore the environment, coal mining in the oxidizing environment, Flow iron ore mine with water and exposed to the air, after a series of oxidation and hydrolysis, so that water acidic. formation of acidic mine water. On groundwater and other environmental facilities, and so on have a certain impact on the environment and destruction. In this paper, the acidic mine water hazards, and the formation of acid mine water in the prevention and treatment of simple exposition. Keywords : mining activities acidic mine water prevention and correction of the environmental impact of coal a foreword is China's main energy, China accounted for one-time energy above 76%, will conduct extensive mining. Mining process undermined the seam office environment, the reduction of its original environment into oxidizing environment. Coal generally contain about 0.3% ~ 5% of sulfur, mainly in the form of pyrite, sulfur coal accounts for about 2 / 3. Coal mining in the oxidizing environment, flow and iron ore mine water and exposed to the air, after a series of oxidation, hydrolysis reaction to produce sulfuric acid and iron hydroxide, acidic water showed that the production of acid mine water. PH value lower than the six said acidic mine water mine water. Acid mine water in parts of the country in the South in particular coal mine were more widely. South China coal mine water in general pH 2.5 ~ 5.8, sometimes 2.0. Low pH causes and coal of high sulfur closely related. Acid mine water to the formation of ground water have caused serious pollution, while also corrosion pipes, pumps, Underground rail, and other equipment and the concrete wall, but also serious pollution of surface water and soil, river shrimp pictures, soil compaction, crops wither and affect human health. An acidic mine water hazards mine water pH is below 6 is acidic, metal equipment for a certain corrosive; pH is less than 4 has strong corrosive influence on the safety in production and the ecological environment in mining areas serious harm. Specifically, there are the following : a "corrosive underground rail, rope and other coal transport equipment. If rail, rope by the pH value "4 acidic mine water erosion, 10 days to Jishitian its intensity will be greatly reduced, Transport can cause accidents; 2 "prospecting low pH goaf water, Quality Control iron pipes and the gate under the flow erosion corrosion soon.3 "acidic mine water SO42-content high, and cement production of certain components interact water sulfate crystallization. These salts are generated when the expansion. After determination of when SO42-generation CaSO4 • 2H2O, the volume increased by 100%; Formation MgSO4.7H2O, v olume increased 430%; Volume increases, the structure of concrete structures.4 "acidic mine water or environmental pollution. Acid mine water is discharged into rivers, the quality of pH less than 4:00, would fish died; Acidic mine water into the soil, damage granular soil structure, soil compaction, arid crop yields fall, affecting workers and peasants; Acid mine water humans can not drink that long-term exposure, people will limbs broken, eyes suffering, enter the body through the food chain. affect human health. 2 acidic mine water and the reasons are mostly coal strata formed in the reduction environment, containing pyrite (FeS2) formed in the seam-reduction environment. Coal generally contain about 0.3% ~ 5% of sulfur, mainly in the form of pyrite, sulfur coal accounts for about 2 / 3. Coal mining in the oxidizing environment, flow and iron ore mine water and exposed to the air, after a series of oxidation, hydrolysis reaction to produce sulfuric acid and iron hydroxide, acidic water showed that the production of acid mine water. Acidic mine water that is the main reason for forming the main chemical reaction as follows : a "pyrite oxidation and free sulfate ferrous sulfate : 2FeS2 O2 +7 +2 +2 H2O 2H2SO4 FeSO4 2 "ferrous sulfate in the role of oxygen free Under into sulfate : 4FeSO4 +2 Cp'2Fe2 H2SO4 + O2 (SO4) 3 +2 H2O 3 "in the mine water The oxidation of ferrous sulfate, sometimes not necessarily need to sulfate : 12FeS2 O2 +6 +3 H2O 4Fe2 (SO4) 3 +4 Fe (OH) 3 4 "mine water Sulfate is further dissolved sulfide minerals in various roles : Fe2 (SO4) 3 + MS + H2O + / 2 + O2 M SO4 H2SO FeSO4 +5 " ferric sulfate in the water occurred weak acid hydrolysis sulfate produced free : Fe2 (SO4) 3 +6 H2O two Fe (OH) 3 +3 H2SO4 6 "deep in the mine containing H2S high, the reduction of conditions, the ferrous sulfate-rich mine water can produce sulfuric acid free : 2FeSO4 +5 FeS2 H2S 2 +3 +4 S + H2O H2SO4 acidic mine water in addition to the nature and sulfur coal on the other, with the mine water discharge, confined state, ventilation conditions, seam inclination, mining depth and size, water flow channels and other geological conditions and mining methods. Mine Inflow stability, stability of acidic water; Confined poor, good air circulation, the more acidic the water, Fe3 + ion content more; Instead, the acid is weak, the more Fe2 + ion; more deep mining of coal with a sulfur content higher; The larger the area of mining, water flows through the channel longer, oxidation, hydrolysis reactions from the more full, the water more acidic strong, If not weak. 3 acidic mine water prevention and control • a three acidic mine water under the Prevention of acidic mine water formation conditions and causes from source reduction, reductions, reduced when three aspects to prevent or mitigate damage. 1 "by the source : the seizure election made use of mineral acid, being the case. The main coal-bed mineral create acid when in a mixture of coal pyrite nodules and coal with a sulfur content itself. Coal mining rate is low and residual coal pillars or floating coal lost, abandoned pyrite nodules underground goaf, in which long-term water immersion, Acidic water produced is a major source. Face to reduce the loss of float coal, theuse of positive seized election pyrite nodules, can reduce the production of acidic water substances. Intercept surface water, reduce infiltration. For example, the filling of waste, control of roof to prevent collapse fissures along the surface water immersion goaf. In Underground, particularly old or abandoned wells closed shaft, the mine water discharge appropriate antibacterial agent, kill or inhibit microbial activity, or reduce the microbial mine water quantity. By reducing microbial sulfide on the effective role and to control the generation of acid mine drainage purposes. 2 "reduced discharge : the establishment of specialized drainage system, centralized emission acidic water, and storing up on the surface, it evaporated, condensed, then to be addressed to remove pollution. 3 "to reduce emissions of acid water in time : to reduce the underground mine water in the length of stay, in a certain extent, to reduce the microbial coal oxidation of sulphides, thus helping to reduce acid mine water. Containing pyrite, sulfur, surface water leakage conditions for a good shallow seam, or have formed strong acidic water stagnant water in the old cellar, the pioneering layout to weigh the pros and arrangements, not early in the mine prospecting or mining, leaving the end of mine water treatment avoid long-term emissions acidic water. • 2 3 acidic mine water treatment in certain geological conditions, Acidic water with calcium sulfate rock or other basic mineral occurrence and the reaction decreases acidity. Neutralizer with caustic soda used for less, less sludge is generated, but the total water hardness is often high, while reducing the acidity of the water. However, an increase in the hardness, and the high cost is no longer. Currently, treatment for a neutralizer to the milk of lime, limestone for the neutralizer and limestone -- lime, microbiological method and wetlands treatment. Neutralizer milk of lime treatment method applicable to the handling of a strong acid, Inflow smaller mine water; Limestone -- lime applied to various acidic mine water. especially when acidic mine water Fe2 + ions more applicable, but also can reduce the amount of lime; microbiological method applied when the basic tenets of iron oxide bacterial oxidation than iron, bacteria from the aquatic environment intake of iron, then to form ferric hydroxide precipitation-iron in their mucus secretions, Acidic water at the low iron into high-iron precipitates out and then reuse limestone and free sulfuric acid, can reduce investment, reduce sediment. Wetlands Act also known as shallow marshes, this method is low cost and easy operation, high efficiency, specific methods not go into details here. Conclusions Most coal strata formed and restore the environment, coal mining in the oxidizing environment, Flow iron ore mine with water and exposed to the air, after a series of oxidation and hydrolysis, so that water acidic. formation of acidic mine water. On groundwater and other environmental facilities, and so on have a certain impact on the environment and destruction, Meanwhile harmful to human health caused some influence. Based on the acidic mine water cause analysis,and to take certain preventive and treatment measures, reduce acid mine water pollution in the groundwater, environmental and other facilities and the damage caused to human health effects. References : [1] Wang Chun compiled, "hydrogeology basis," Geological Press, Beijing. [2] Yuan Ming-shun, the environment and groundwater hydraulics research papers on the topic, the Yangtze River Academy of Sciences reported that 1994,3.[3], Lin Feng, Li Changhui, Tian Chunsheng, "environmental hydrogeology," Beijing, geological Press, 1990,21.附录B简介：煤炭是我国的主要能源，在我国一次性能源中占76％以上。
采矿工程中英文对照外文翻译文献
中英文对照外文翻译文献(文档含英文原文和中文翻译)译文：新技术和新理论的采矿业跨世纪发展摘要：煤炭产业需要更长远的发展，对工作中所讨论的热点在工业中出现新的理论和高科技成功使用在二十世纪末是最美好的，作为被关心的问题需要较快一步的发展，在20世纪中后期产生的新型、高速的新技术是最有吸引力和标志性的，即使在所有行业中不同的冲击变得起来越相关以及部门间彼此合作并明确地叙述许多新的理论，煤炭行业的新科技和新理论是不可避免的，并且包括一切的不可能性。
作者在这篇文章中阐述了他关于采矿学的发展问题的意见，举出了许多令人信服的事实，并对大部分新的情况予以求证。
关键字:采矿工程，矿业产业, 矿业经济学,新技术和高科技1.采矿在国民经济中的重要性今天，科技世界的发展已经引起了对采矿空前的不容忽视，空间工程，信息工程，生物工程和海洋工程的发展，新能源的发现和研究与发展以及新原料在目前和将来逐渐地改变着人类生活的每个方面。
“科学技术是第一生产力”指出了新科技在国民经济的中扮演了重要的角色。
在全球的一些大的国家中，互相竞争为的是努力探测外部的空间，我们不应该忘记基本的事实：有超过五十亿个人生活在地球上。
想要保住地球上的人类，我们必须做到以下四个方面：也就是营养物，原料，燃料和环境。
营养物主要是空气、水、森林、谷物和各种植物，它们都是来自于自然。
原料有铁、铁的金属，稀罕的金属，宝贵的化学的原料和建材的金属。
燃料如：煤炭，石油，天然气，铀，放射性金属元素和其他的发光要素。
这些也在自然界中发生。
最后一种是靠人类来维持的生态环境。
在上述中三个必要的物质中，原料和燃料从地球表面经过采矿学取出服务人类。
生态学的环境和采矿已及上述的三个必要的财产抽出有莫大的关系。
然而，随着新技术和它们进入煤炭行业成果的提高，逐渐使它由朝阳产业变成当日落业并逐渐地褪色消失。
如采矿产业是最古老的劳工即强烈传统的产业，因此，那里没落是在一个民族的特定部份需要的印象而且要再作任何的更高深的研究，并在此之上发展采矿。
采矿工程专业毕业设计外文文献翻译(中英文翻译)
外文原文：Adopt the crest of the coal work noodles plank managementproblem studyCrest the plank management is the point that adopts a safe management of the coal work noodles.Statistics according to the data, crest the plank trouble has 60% of the coal mine trouble about, adopting the trouble of the coal work noodles and having a crest 70% of the plank trouble above.Therefore, we have to strengthen a plank management, reducing to adopt the coal work noodles crest the occurrence of the plank trouble.1,the definition of the crest,scaleboard and it categorizeEndow with the existence coal seam on of the close by rock strata be called a plank, endow with the existence coal seam under of the close by rock strata be called scaleboard.Crest the rock,strength of the scaleboard and absorb water sex and digging to work the management of the noodles contain direct relation, they is certain crest the plank protect a way and choose to adopt the empty area processing method of main basis.1.1 planks categorizeAccording to rock,thickness and return to adopt process to fall in the 垮of difficult easy degree, crest the plank is divided into the false crest,direct crest and old crest.According to direct crest sport to adopt a field to the influence for press, the direct crest is divided into broken up,unsteady,medium etc. stability,stability,strong and tough crest plank etc. is five.According to old crest the sport Be work mineral inside the noodles press to present degree and to work safe threat of noodles of size, the old crest is is divided in to press very and severely, press mightiness, press to compare obviously, don't obviously press etc. is four.1.2 scaleboards categorizeAccording to the opposite position relation of the rock strata and the coal seam, the scaleboard is divided into direct bottom with the old bottom.Locate coal seam directly under of the rock strata be called direct bottom;locate the direct bottom or coal seam under of the rock strata be called old bottom.The coal seam crest the scaleboard type expects the influence of the geology structure sport after be subjected to the deposition environment and, its growth in different region degree dissimilarity, the coal seam possibility for have isn't whole.2,crest that need to be control plank classification and adopt the processing way of the empty areaAccording to different crest the plank type and property, choose to pay to protect a way and adopt the empty area processing method differently, is a plank management of basic principle.2.1 crest needed to pull to make plank classificationPress a knothole rock strata strength, the crest plank that needs to be control can is divided into: general crest the plank,slowness descend to sink a plank and is whole fall the crest of the cave in the danger plank etc..2.2 work noodles adopt the processing method of the empty areaThe processing method that adopts empty area mainly has: all 垮s fall a method,partial full to fill a method,the coal pillar to prop up a method to alleviate to descend to sink a method slowly etc..3,crest the plank pressure present a characteristic3.1 top the cover rock strata of the sport regulation and the work in front pay to accept pressure to distribute behindDuring the period of mine, adopt empty area above of the rock strata will take place ambulation, according to crest the plank change mind condition, taking the cranny rock strata in up the cover rock strata follow the work noodles to push forward the direction demarcation as three areas: the coal wall prop up the influence area,leave layer area and re- press solid area.The noodles opens to slice an eye to go to push forward forward in the process from the work, break original should the equilibrium of the dint field, cause should the dint re- distribute.Be adopting the coal work noodles to become to pay to accept pressure in front and back, it concretely distributes shape to have something to do with adopting the empty area processing method.3.2 first times to press to press a main manifestation with the periodFirst time to press a main manifestation:BE a plank"by oneself the vield song" range enlargement;the coal wall transform and fall to fall(the slice help);pay to protect to drill bottom etc..First time to press to want to keep on more and suddenly and generally for 2-3 days.Period to press a main manifestation:Main manifestation BE:crest the plank descend to sink nasty play increment of speed, crest the plank descend to sink quantity to become big;pay what pillar be subjected to load widespread increment;adopt empty area to hang a crest;pay pillar to make a noise;cause the coal wall slice to help,pay pillar to damage,crest plank occurrence the step descend to sink etc..If pay the pillar parameter choice to be unsuited to a proper or single body to pay the pillar stability worse, may cause the partial crest or crest plank follow the work noodles to slice to fall etc..4,crest the plank choice for protectThe work noodles the function for protect decelerate a plank to descend to sink, supporting to control a crest to be apart from the knothole integrity inside the crest, assurance work space safety.4.1 choices that protect material and formPay to protect material to mainly there are the metals support and the wood support.Pay to protect a form to mainly have a little the pillar to protect,the cote type protect to press a support with liquid.4.2s protect a specification choiceWhile choosing to pay to protect specification, mainly control the following 2:00:1.Control the work noodles adopt high and its variety.Generally can according to drill a holethe pillar form or have already dug the tunnel data of to make sure to adopt high.From last the movable regulation of the cover rock strata, can the initial assurance crest plank at biggest control a crest to be apart from place of average biggest descend to sink quantity, select to pay a pillar model number suitablely2 control the crest plank of the normal appearance to descend to sink the quantity and support can the draw back pute the biggest and high Hmax and minimum and high Hmin that pays pillar, select specification of pay the prehensive the pillar model number and specification, check related anticipate, assurance the model number of the pillar.5,the work noodles manages everyday of pointEveryday crest the point of plank management is the with accuracy certain protects density and control a method, right arrangement and organize to adopt coal and control a crest to relate to in fixed time, strengthen to pay to protect the quality management before press, the assistance that chooses to use a good necessity protect etc., attain to expel to emit a trouble, assurance the purpose of[with] efficiency.1 choice that protects density and controls a methodAccording to the work noodles crest plank rock,adopt a periodic to press obvious degree, press strength and to press in front and back a crest knothole variety a circumstance etc., the certain protect density and control a method.It adopt coal in 2 production lines with control of the crest to relate to in fixed timePeriod to don't obviously press to adopt a field, emphasize to pay to protect,adopt coal, control a parallel homework, possibly contract to adopt coal,return to pillar to put distance between an operations with speed the work noodles propulsion degree;period to press more and obviously adopt a field, at to press in front and back adopt different of,control the relation organization project, before press should not adopt coal,put a crest in the meantime homework, press after should adopt to adopt coal,put a crest to keep minimum wrong be apart from parallel homework.Field to strengthen to pay to protect the quality management assurance to pay pillar to have to prop up dint,prevent°from paying pillar to drill bottom enough before press,right adoption the assistance protect.Adopt the coal work noodles crest, the plank manages everyday of the key lie in raising the spot management,the operation level, paying to protect and adapt to adopt a field to press and crest the scaleboard variety circumstance, adopt right of the assistance protect measure, well exertivecontrol a result.译文：采煤工作面的顶板管理问题探讨顶板管理是采煤工作面安全管理的重点。
采煤机相关英文文献翻译
英文原文：Control strategy for an intelligent shearer height adjusting systemFAN Qigao*, LI Wei, WANG Yuqiao, ZHOU Lijuan, YANG Xuefeng, YE Guo School of Mechanical & Electrical Engineering, China University of Mining & Technology, Xuzhou 221008, ChinaAbstract: An intelligent shearer height adjusting system is a key technology for mining at a man-less working face. A control strategy for a shearer height adjusting system based on a mathematical model of the height adjusting mechanism is proposed. It considers the non-linearity and time variations in the control process and uses Dynamic Fuzzy Neural Networks (D-FNN). The inverse characteristics of the system are studied. An adaptive on-line learning and error compensation mechanism guarantees system real-time performance and reliability. Parameters from a German Eickhoff SL500 shearer were used with Matlab/Simulink to simulate a height adjusting control system. Simulation shows that the trace error of a D-FNN controller is smaller than that of a PID controller. Also, the D-FNN control scheme has good generalization and tracking performance, which allow it to satisfy the needs of a shearer height adjusting system.Keywords: shearer; height adjusting system; dynamic fuzzy neural network1 IntroductionThe shearer and its control system are main components for coal mining. The shearing process includes drum lifting and traction control. Domestic shear drum lifting now uses manual adjustments after artificial observation or a geometric track cutting-memory method after trial manual adjustments from test cuttings. The installation of sensors on the shearer that could identify coal-rock has been proposed. Information from the sensors would be used to achieve drum height control directly by automatically lifting the shearer]1[. This technology, which is based on simple drum height feedback, has not been widely applied due to the structural complexity of the coal seam, technical problems related to identification ofthe coal-rock interface as well as roof, and floor, requirements for such comprehensive coal mining mechanization. Others have proposed an intelligent shearer height adjusting system based on a self-adaptive PID neural network control method]2[. This requires data samples from an operating shearer height adjusting system followed by careful choice of the neural network and adjustment of the algorithmic parameters. The suitability of the system would then be determined by checking performance against test samples. After the structure and parameters were determined the trained neural network could be applied to practical systems. The parameters could be ad-justed further while the system was running toachieve self-adaptive learning and control. Setting up such a system involves considerable uncertainty and a great deal of time.Considering the factors and the need for improving product quality and resource recovery by automatic control of the drum height we propose a new method called the shearer intelligent height adjusting system control method. It is based on Dynamic Fuzzy Neural Networks (D-FNN). D-FNN are neural networks that have the characteristics of powerful on-line learning, fast learning and good generalization. D-FNN give real-time control and improve dynamic characteristics of a shearer height adjusting system and provide a theoretical basis for designing an intelligent height adjusting control system for the shearer.2 Analysis of a shearer height adjusting system2.1 Structure of the shearer height adjusting systemThe shearer height adjusting mechanism uses a hydraulic servo system having good dynamic performance. Fig. 1 diagrams a drum shearer. The electro-hydraulic servo system controls extension of the hydraulic cylinder and moves the rocker arm to set the height. The adjusting mechanism is a planar open chain consisting of a series of connected rod structures and corresponding kinematic pairs. A descripion of the relative motion of the parts shows how height adjustment occurs. A detailed motion analysis follows. Suppose:1) All components are rigid and elastic deformation is ignored;2) Gaps between all mechanisms are ignored.2.2 Mathematical analysis of the shearer height adjustment systemFig. 2 shows the initial position of the hydraulic cylinder as A L , the end position as B L , the long arm of the rocker arm is L, short arm is R L , the draw bar between the height adjustment cylinder and the rocker arm is G L , the distance between the height adjustment cylinder and the rocker pivot is D and the angle between the long arm and the short arm is 0θ.Definition 1. Shearer mining height H:H=L θsin (1) End position B L is given by x L L A B ∆+= allowing the displacement of thehydraulic cylinder, x ∆, to be established.Definition 2. Displacement of the hydraulic cylinder, x ∆ , is:A B L L x -=∆ (2) whereWe write:(3)whereSubstitution gives x ∆ as: (4) Since b is given by θθβ-=` x ∆ can be expressed as a function of rocker-height to angle:(5) Kinetic analysis of the model shearer height adjusting system shows it is a third ordersystem. The system transfer function is [3]:(6) where K is the system gain, ζ is the system damping ratio, w is the natural frequency of the system, F (s) the Laplace transform of the servo mechanism, )(s x ∆ the Laplace transform of x ∆ (in Eq.(5)),x ∆ is derived from Eq.(6), the swing angle, θ , of the rocker arm is from Eq.(5) and θ controls the feedback.Since the height adjusting system is non-linear and a time-varying dynamic system a traditional PID controller cannot provide satisfactory control. D-FNN are proposed as meeting the requirements of reliability and real time performance.3 Dynamic fuzzy neural networksD-FNN are based on the expansion of Radial Basis Function (RBF) neural networks. The prominent characteristics of this learning algorithm are the simultaneous adjustment of parameters and the identification of an appropriate structure. This provides rapid learning suitable for real-time control and for modeling of the shearer height adjusting system ]64[- The structure of a dynamic fuzzy neural network is shown in Fig. 3.In Fig. 3 1x , 2x , …, r x are the system input variables, y is the system output, ij MF is the membership function, j, of the input variable, i, j R is the fuzzy rule of membership function j, j N is the normalized node of j, i ω is the connection weight of rule j and u is the whole system rule number.The swing angle, θ , of the rocker arm was chosen as the system input variable that controls expansion of the hydraulic cylinder. A Gaussian function, Eq.(7), is used for the membership function.(7)where i ranges from 1 to r, j ranges from 1 to u,ij u is the membership function, j, of i x , ij c is the center of the Gaussian membership function, j, of i x , j is the width of the Gaussian membership function, j, of i x , r is the input variable number and u is the number of the membership function as well as the whole system rule number.The output of j R , rule j, is obtained from:(8) where X is given by:and the center of RBF neural network j is given by:This gives the D-FNN model as: (9)where α is the connection weight of rule i.4 D-FNN control strategyThe D-FNN control scheme is shown in Fig. 4. The basic idea is obtaining the inverse characteristic of the shearer height adjusting system and then producing a compensation signal from this inverse dynamic model. There are two dynamic fuzzy neural networks here:A and B. Network A is for system weight training while networkB is a copy of the trained A network that is used for producing the control signal.The control algorithm is:(10) where x Δ is the expected displacement of the height ad justing hydraulic cylinder; PD Δx the actual displacement of the cylinder produced by the PD controller and DFNNB Δx the actual displacement of the cylinder produced by network B.The PD controller is for faster and more accurate tracking performance. The key to the D-FNN controlsystem is the training of D-FNN B to minimize the squared error between expected and actual displacements produced by network B]87[ :(11)A gradient descent method is used for the weight adjusting algorithm]9[:(12) where λ is the learning rate and λ >0. λ has a large influence on the convergence rate. Increasing of λcan speed up the convergence rate, which is more suitable for time-varying system modeling and control. At the same time the anti-interference performance of the system declines. A decrease in λ slows down convergence but produces a system less sensitive to interference. A self-adjusting learning rate method is proposed herein, the principle being that when the new error exceeds the last error overshooting has occurred and λ should be reduced. If the new error is smaller than the last error the weig ht adjustments are effective and λ should be increased. If the error is constant then λ is kept the same. This may be written as:(13) Tests show that D-FNN using the self-adjusting learning rate method requires much less training time than systems using a fixed learning rate.5 System simulationThe mathematical model and a D-FNN control algorithm may be used in a model shearer height ad-justing system built using Matlab/Simulink[]1510[-. The actual parameters are from a German Eickhoff SL500 machine. The shearer maximum cutting height is 5.50 m and the foot wall is 1.08 m. The angle of the rocker arm is –21.3°~+55°. The draw bar, LG , is 2.05 m, the short arm, LR, is 1.20 m, D is 0.9 m and the angle 670=θ5.1 Simulation of a D-FNN controllerSuppose the rocker arm moves within a range of –21.3°~+55°. The D-FNN control strategy traces the trajectory of the rocker arm and the trajectory tracing error are shown in Fig. 5. In Fig. 5b the maximum trajectory tracing error of the rocker arm is 0.65°, which occurs early in the training stage. At this point the D-FNN is undergoing on-line learning, namely learning the proper inverse model of the shearer height adjusting system. So in the early stage network B has insufficient accuracy to compensate for error in the control signals. But as training proceeds the average error drops until at the final stage it has been reduced to ±0.1°, which meets the system requirements.5.2 Simulation of a PID controllerThe trajectory of the rocker arm, and the corresponding tracing error, are shown in Fig. 6 for the traditional PID controller.As shown in Fig. 6b, the maximum trajectory error is 5.8°; this is unacceptable for the whole system. The simulation results show that the D-FNN controller is more robust and adjusts faster.6 Conclusions1) A mathematical analysis of the shearer height adjusting structure was used to build a mathematical model. The constraints between the control and feedback variables of the shearer height adjusting system were determined from the model.2) The combined advantages of fuzzy control and neural network control used in the D-FNN control strategy to adjust shearer height were described. A proposed control scheme of the system, having the desired inverse characteristic, is derived. By adjusting the weights and compensating for accuracy the control scheme satisfactorily met the needs of a height adjusting system.3) A simulated D-FNN controller system using parameters from an Eickhoff SL500 shearer was compared to a traditional PID controller: the D-FNN controller was more accurate. The D-FNN algorithm overcomes limitations of traditional network optimization algorithms andavoids falling into local minimum points. Self adaptive, on-line learning greatly improves the training speed. The system stability and accuracy meet the requirements for a shearer height adjusting systemAcknowledgementsFinancial support for this work, provided by the National High Technology Research and Development Program of China (No.2008AA062202), and China University of Mining & Technology Scaling Program, are gratefully acknowledged.References[1] Zhang J M, Fan X, Zhao X S. Automatic horizon control system of coal mining machine. Journal of China University of Mining & Technology, 2002, 31(4): 415-418. (In Chinese)[2] Liang Y W, Xiong S B. Neuarl network and PID hybrid adaptive control for horizontal control of shearer. In: Proceeding of the 7th International Conference on Control,Automation, Robotics and Vision IEEE. Singapore, 2002: 671-674. (In Chinese)[3] Lei Y Y, Yin Z X, Qian H. Study on hydraulic automatic ranging cutting height of shearer. Journal of Chongqing University, 1994, 17(1): 52-58. (In Chinese)[4] Er M J, Wu S Q. A fast learning algorithm for parsimonious fuzzy neural systems. Fuzzy Sets and Systems, 2002, 126(3): 337-351.[5] Gao Y, Er M J, Yang S. Adaptive fuzzy neural control of robot manipulators. IEEE Trans Ind Electron, 2001, 48: 1274-1278.[6] Chang Y C. Adaptive fuzzy-based tracking control for nonlinear SISO systems via VSS and H approaches. IEEE Trans Fuzzy Syst, 2001(9): 278-292.[7] Li C, Lee C Y. Self-organizing neuro-fuzzy system for control of unknown plants. IEEE Transactions on Fuzzy Systems, 2003, 11(1): 135-150.[8] Er M J, Low C B, Nah K H, Lim M H, Ng S Y. Real-time implementation of a dynamic fuzzy neural networks controller for SCARA. Microprocessors and Microsystems, 2002, 26(9/10): 449-461.[9] Juang C F, Lin C T. Noisy speech processing by recurrently adaptive fuzzy filters. IEEETransactions on Fuzzy Systems, 2001, 9(1): 139-152.[10] Esposito A, Marinaro M, Oricchio D, Scarpetta S. Approximation of continuous and discontinuous mappings by a growing neural RBF-based algorithm. Neural Networks, 2000, 13(6): 651-665.[11] Magee D P. Matlab extensions for the development, testing and verification of real-time DSP software. In: Proceedings of 42nd Annual Conf Design Automation. California, 2005: 603-606.[12] Bhatt T M, McCain D. Matlab as a development environment for FPGA design. In: Proceedings of 42nd Annual Conf Design Automation. California, 2005: 607-610.[13] Yang Y J, Deng H Y, Li X. Simulation of screening process based on MATLAB/Simulink. Journal of China University of Mining & Technology, 2006, 16(3): 330- 332.[14] Liu S Y, Du C L, Cui X X, Cheng X. Model test of the cutting properties of a shearer drum. Mining Science and Technology, 2009, 19(1): 74-78.[15] Fang X Q, Zhao J J, Hu Y. Tests and error analysis of a self-positioning shearer operating at a manless working face. Mining Science and Technology, 2010, 20(1): 53- 58.中文翻译：采煤机高度智能调节系统控制方案范启高，周丽娟，李伟，王玉桥，杨学锋，叶国安机电工程学院，中国矿业大学，徐州221008，中国摘要：一种采煤机高度智能调节系统是在无人工作面开采的关键技术。
煤矿带式输送机中英文对照外文翻译文献
中英文对照外文翻译A Comparison of Soft Start Mechanisms forMining Belt Conveyors1800 Washington Road Pittsburgh, PA 15241 Belt Conveyors are an important method for transportation of bulk materials in the mining industry. The control of the application of the starting torque from the belt drive system to the belt fabric affects the performance, life cost, and reliability of the conveyor. This paper examines applications of each starting method within the coal mining industry.INTRODUCTIONThe force required to move a belt conveyor must be transmitted by the drive pulley via friction between the drive pulley and the belt fabric. In order to transmit power there must be a difference in the belt tension as it approaches and leaves the drive pulley. These conditions are true for steady state running, starting, and stopping. Traditionally, belt designs are based on static calculations of running forces. Since starting and stopping are not examined in detail, safety factors are applied to static loadings (Harrison, 1987). This paper will primarily address the starting or acceleration duty of the conveyor. The belt designer must control starting acceleration to prevent excessive tension in the belt fabric and forces in the belt drive system (Suttees, 1986). High acceleration forces can adversely affect the belt fabric, belt splices, drive pulleys, idler pulleys, shafts, bearings, speed reducers, and couplings. Uncontrolled acceleration forces cancause belt conveyor system performance problems with vertical curves, excessive belt take-up movement, loss of drive pulley friction, spillage of materials, and festooning of the belt fabric. The belt designer is confronted with two problems, The belt drive system must produce a minimum torque powerful enough to start the conveyor, and controlled such that the acceleration forces are within safe limits. Smooth starting of the conveyor can be accomplished by the use of drive torque control equipment, either mechanical or electrical, or a combination of the two (CEM, 1979).SOFT START MECHANISM EVALUATION CRITERIONWhat is the best belt conveyor drive system? The answer depends on many variables. The best system is one that provides acceptable control for starting, running, and stopping at a reasonable cost and with high reliability (Lewdly and Sugarcane, 1978). Belt Drive System For the purposes of this paper we will assume that belt conveyors are almost always driven by electrical prime movers (Goodyear Tire and Rubber, 1982). The belt "drive system" shall consist of multiple components including the electrical prime mover, the electrical motor starter with control system, the motor coupling, the speed reducer, the low speed coupling, the belt drive pulley, and the pulley brake or hold back (Cur, 1986). It is important that the belt designer examine the applicability of each system component to the particular application. For the purpose of this paper, we will assume that all drive system components are located in the fresh air, non-permissible, areas of the mine, or in non-hazardous, National Electrical Code, Article 500 explosion-proof, areas of the surface of the mine.Belt Drive Component Attributes Size.Certain drive components are available and practical in different size ranges. For this discussion, we will assume that belt drive systems range from fractional horsepower to multiples of thousands of horsepower. Small drive systems are often below 50 horsepower. Medium systems range from 50 to 1000 horsepower. Large systems can be considered above 1000 horsepower. Divisionof sizes into these groups is entirely arbitrary. Care must be taken to resist the temptation to over motor or under motor a belt flight to enhance standardization. An over motored drive results in poor efficiency and the potential for high torques, while an under motored drive could result in destructive overspending on regeneration, or overheating with shortened motor life (Lords, et al., 1978). Torque Control.Belt designers try to limit the starting torque to no more than 150% of the running torque (CEMA, 1979; Goodyear, 1982). The limit on the applied starting torque is often the limit of rating of the belt carcass, belt splice, pulley lagging, or shaft deflections. On larger belts and belts with optimized sized components, torque limits of 110% through 125% are common (Elberton, 1986). In addition to a torque limit, the belt starter may be required to limit torque increments that would stretch belting and cause traveling waves. An ideal starting control system would apply a pretension torque to the belt at rest up to the point of breakaway, or movement of the entire belt, then a torque equal to the movement requirements of the belt with load plus a constant torque to accelerate the inertia of the system components from rest to final running speed. This would minimize system transient forces and belt stretch (Shultz, 1992). Different drive systems exhibit varying ability to control the application of torques to the belt at rest and at different speeds. Also, the conveyor itself exhibits two extremes of loading. An empty belt normally presents the smallest required torque for breakaway and acceleration, while a fully loaded belt presents the highest required torque. A mining drive system must be capable of scaling the applied torque from a 2/1 ratio for a horizontal simple belt arrangement, to a 10/1 ranges for an inclined or complex belt profile.Thermal Rating.During starting and running, each drive system may dissipate waste heat. The waste heat may be liberated in the electrical motor, the electrical controls,, the couplings, the speed reducer, or the belt braking system. The thermal load ofeach start Is dependent on the amount of belt load and the duration of the start. The designer must fulfill the application requirements for repeated starts after running the conveyor at full load. Typical mining belt starting duties vary from 3 to 10 starts per hour equally spaced, or 2 to 4 starts in succession. Repeated starting may require the dreading or over sizing of system components. There is a direct relationship between thermal rating for repeated starts and costs. Variable Speed. Some belt drive systems are suitable for controlling the starting torque and speed, but only run at constant speed. Some belt applications would require a drive system capable of running for extended periods at less than full speed. This is useful when the drive load must be shared with other drives, the belt is used as a process feeder for rate control of the conveyed material, the belt speed is optimized for the haulage rate, the belt is used at slower speeds to transport men or materials, or the belt is run a slow inspection or inching speed for maintenance purposes (Hager, 1991). The variable speed belt drive will require a control system based on some algorithm to regulate operating speed. Regeneration or Overhauling Load. Some belt profiles present the potential for overhauling loads where the belt system supplies energy to the drive system. Not all drive systems have the ability to accept regenerated energy from the load. Some drives can accept energy from the load and return it to the power line for use by other loads. Other drives accept energy from the load and dissipate it into designated dynamic or mechanical braking elements. Some belt profiles switch from motoring to regeneration during operation. Can the drive system accept regenerated energy of a certain magnitude for the application? Does the drive system have to control or modulate the amount of retarding force during overhauling? Does the overhauling occur when running and starting? Maintenance and Supporting Systems. Each drive system will require periodic preventative maintenance. Replaceable items would include motor brushes, bearings, brake pads, dissipation resistors, oils, and cooling water. If the drive system is conservatively engineered and operated, the lower stress onconsumables will result in lower maintenance costs. Some drives require supporting systems such as circulating oil for lubrication, cooling air or water, environmental dust filtering, or computer instrumentation. The maintenance of the supporting systems can affect the reliability of the drive system.Cost.The drive designer will examine the cost of each drive system. The total cost is the sum of the first capital cost to acquire the drive, the cost to install and commission the drive, the cost to operate the drive, and the cost to maintain the drive. The cost for power to operate the drive may vary widely with different locations. The designer strives to meet all system performance requirements at lowest total cost. Often more than one drive system may satisfy all system performance criterions at competitive costs.Complexity.The preferred drive arrangement is the simplest, such as a single motor driving through a single head pulley. However, mechanical, economic, and functional requirements often necessitate the use of complex drives. The belt designer must balance the need for sophistication against the problems that accompany complex systems. Complex systems require additional design engineering for successful deployment. An often-overlooked cost in a complex system is the cost of training onsite personnel, or the cost of downtime as a result of insufficient training.SOFT START DRIVE CONTROL LOGICEach drive system will require a control system to regulate the starting mechanism. The most common type of control used on smaller to medium sized drives with simple profiles is termed "Open Loop Acceleration Control". In open loop, the control system is previously configured to sequence the starting mechanism in a prescribed manner, usually based on time. In open loop control, drive-operating parameters such as current, torque, or speed do not influence sequence operation. This method presumes that the control designer hasadequately modeled drive system performance on the conveyor. For larger or more complex belts, "Closed Loop" or "Feedback" control may he utilized. In closed loop control, during starting, the control system monitors via sensors drive operating parameters such as current level of the motor, speed of the belt, or force on the belt, and modifies the starting sequence to control, limit, or optimize one or wore parameters. Closed loop control systems modify the starting applied force between an empty and fully loaded conveyor. The constants in the mathematical model related to the measured variable versus the system drive response are termed the tuning constants. These constants must be properly adjusted for successful application to each conveyor. The most common schemes for closed loop control of conveyor starts are tachometer feedback for speed control and load cell force or drive force feedback for torque control. On some complex systems, It is desirable to have the closed loop control system adjust itself for various encountered conveyor conditions. This is termed "Adaptive Control". These extremes can involve vast variations in loadings, temperature of the belting, location of the loading on the profile, or multiple drive options on the conveyor. There are three common adaptive methods. The first involves decisions made before the start, or 'Restart Conditioning'. If the control system could know that the belt is empty, it would reduce initial force and lengthen the application of acceleration force to full speed. If the belt is loaded, the control system would apply pretension forces under stall for less time and supply sufficient torque to adequately accelerate the belt in a timely manner. Since the belt only became loaded during previous running by loading the drive, the average drive current can be sampled when running and retained in a first-in-first-out buffer memory that reflects the belt conveyance time. Then at shutdown the FIFO average may be use4 to precondition some open loop and closed loop set points for the next start. The second method involves decisions that are based on drive observations that occur during initial starting or "Motion Proving'. This usually involves acomparison In time of the drive current or force versus the belt speed. if the drive current or force required early in the sequence is low and motion is initiated, the belt must be unloaded. If the drive current or force required is high and motion is slow in starting, the conveyor must be loaded. This decision can be divided in zones and used to modify the middle and finish of the starsequence control. The third method involves a comparison of the belt speed versus time for this start against historical limits of belt acceleration, or'Acceleration Envelope Monitoring'. At start, the belt speed is measured versus time. This is compared with two limiting belt speed curves that are retained in control system memory. The first curve profiles the empty belt when accelerated, and the second one the fully loaded belt. Thus, if the current speed versus time is lower than the loaded profile, it may indicate that the belt is overloaded, impeded, or drive malfunction. If the current speed versus time is higher than the empty profile, it may indicate a broken belt, coupling, or drive malfunction.In either case, the current start is aborted and an alarm issued. CONCLUSIONThe best belt starting system is one that provides acceptable performance under all belt load Conditions at a reasonable cost with high reliability. No one starting system meets all needs. The belt designer must define the starting system attributes that are required for each belt. In general, the AC induction motor with full voltage starting is confined to small belts with simple profiles. The AC induction motor with reduced voltage SCR starting is the base case mining starter for underground belts from small to medium sizes. With recent improvements, the AC motor with fixed fill fluid couplings is the base case for medium to large conveyors with simple profiles. The Wound Rotor Induction Motor drive is the traditional choice for medium to large belts with repeated starting duty or complex profiles that require precise torque control. The DC motor drive, Variable Fill Hydrokinetic drive, and the Variable Mechanical Transmission drive compete for application on belts with extreme profiles orvariable speed at running requirements. The choice is dependent on location environment, competitive price, operating energy losses, speed response, and user familiarity. AC Variable Frequency drive and Brush less DC applications are limited to small to medium sized belts that require precise speed control due to higher present costs and complexity. However, with continuing competitive and technical improvements, the use of synthesized waveform electronic drives will expand.煤矿业带式输送机几种软起动方式的比较1800 年华盛顿路匹兹堡, PA 15241带式运送机是采矿工业运输大批原料的重要方法。
采矿工程专业毕业论文外文翻译
英文原文：Analytical model and application of stressdistribution on mining coal floorAbstract：Given the analysis of underground pressure，a stress calculation model of cola floor stress has been established based on a theory of elasticity．The model presents the law of stress distribution on the relatively fixed position of the mining coal floor：the extent of stress variation in a fixed floor position decreases gradually along with depth．The decreasing rate of the vertical stress is clearly larger than that of the horizontal stress at a specific depth．The direction of the maximum principal stress changes gradually from a vertical direction to a horizontal direction with the advance of the working face．The deformation and permeability of the rock mass of the coal floor are obtained by contrasting the difference of the principal stress established from theoretical calculations with curves of stress-strain and permeability-strain from tests．Which is an important mechanical basis for preventing water inrush from confined aquifers．Key words：model；coal floor；stress distribution；analysis1 IntroductionWith the development of coal seam mining，The stress field of rock strata of coal seam floors will change and continue to be redistributed because of the effect of mining．The results will bring on floor deformation，displacement and possible destruction to attain a new balance[1]．A study of the law of stress distribution of floors has important，practical implications in understanding deformation and destructive characteristics and predicting water inrush from floors and for designing suitable locations for tunnels and selecting maintenance methods when depth increased．At present，the study of the law of stress distribution of floors mostly proceeds from a number of calculations based on finite element analyses and similar material tests[2-6]．In this paper，the study of stress distribution of floors in relatively fixed positions is discussed analytically with a theory of elasticity and we present an application combined with actual data of a particular site．2 Fundamental principleThe formulas of stress distribution are derived from the superposition principle，given the theory of elasticity on distributed loads on a semi-infinite plane[7-8]．The vertical distribution load of AB on a semi-infinite plane is assumed to be q(x)，as illustrated in Fig.1.We want to solve the state of stress at a specific point inside a semi-infinite plane，such as point M ．Supposing the coordinate of point is (x，z)，the micro-1ength dζfrom the origin of coordinate is ζon the AB segment，the micro-concentration force d p=q dζis regarded as its force and the state of stress of the micro-concentration force at point is defined as follows．In order to calculate the stress at point M from all distributed loads，the stress which is caused by every micro-concentration force is superposed．We need to integrate Eq.(1) from ζ= -a to ζ= b and Eq.(1) then becomes：3 Stress calculation of coal seam floor3.1Foundation of the mechanical modelBased on the theory of underground pressure，the mechanical model of supporting pressure in front of the working face can be simplified，as shown in Fig.2[9-11]．Where the OA segment is the plastic area，with a length of x0；the AB segment is the elastic area，with a length of L0x0．In order to calculate easily the supporting pressure of both areas p z(1)，p z(2)，without losing its rational，we can assume the following two linear functions：Where is the supporting pressure of the plastic area(kPa)，the supporting pressure of the elastic area(kPa)，the maximum stress concentration coefficient，the width of the plastic area(m)，H the buried depth of the coal floor(m)，the width of the area affected by the supporting pressure(m) and is the average weight of the volume of the over-lying strata (kN/m3) ．3.2Stress calculation processAccording to the theory of elasticity on distributed loads on a semi-infinite plane，we can use Eq.(2) to calculate the vertical stresses σz(1) and σz(2) and the horizontal stresses σx(1)and σx(2)which are affected by the supporting pressures and ．The stress equations at point M(x, z) can then be obtained correspondingly by superposition (this calculation neglects the effect of the transferred load from the goaf and the overlying strata movement as well as the effect of the initial ground stress because it does not produce subsidiary stress at point M；largely we considered the action of the supporting pressure in front of the working face). The calculations are as follows：Therefore，σz = σz(1)+σz(2)(4) and σx = σx(1)+σx(2)(5). By coordinate transformation(x = x(n = 0，1，2，…))，x is regarded as x0 in Eqs.(4) and (5) and the stress values of each section can be calculated，where the variable expresses the relative distance from the pushing position of the working face to the origin of the coordinate system. Given the related parameters of supporting pressures，the stress values，located at the relatively fixed floor section，(x =) at different depths，can be calculated by computer when the working faces advance.When x = x，Eqs.(4) and (5) can be represented as follows：3.3Example analysisGiven the actual geological conditions and mining technology at the 2702 working face of the Yangcun Colliery of the Yanzhou Mining Group Limited Company，the following related parameters are determined：=3，=5 m，=50 m，=25 kN/m3 and H=500 ing Eqs.(6) and (7)，the stress distribution curves are obtained on the relatively fixed floor section x=at different depths with the working face advancing by calculation. The results are shown means of computer in Figs. 3 and 4.Fig. 3 shows that vertical stress maintains its maximum at the interface between the coal seam and floor on the section x=from the original coordinates and then quickly decreases with the increasing depth and slowly decreases at a specific depth. A similar situation is obtained when the working face advances，i.e.，the range of the vertical stress decreases with an increase in depth. From the results it can be seen that the range of depth, given the variation of vertical stress, is relatively large, i.e., within 40 m. The range of the vertical stress is clearly smaller after the working face advances 30 m.According to the relationship of the variation between vertical and horizontal stress, the multiplication of the variation of vertical stress and its corresponding coefficient of horizontal pressure (λ) is equal to the increment of horizontal stress at the point M[1]. Then the increment of horizontal stress and the horizontal stress at the point M continues to be superposed, which is inversed analysis when the working face advances 30 m. The results of the variation in stress show that the vertical stress is larger than the horizontal stress when the working face is at its original position: the maximum principal stress is the vertical stress; the minimum principal stress is horizontal stress. Because the rate of decrease of the vertical stress is faster than the horizontal stress, the horizontal stress is larger than the vertical stress within 42 m when the working face advances 30 m (for details, see Fig. 4). Considering the effect of the variation in vertical stress, the horizontal stress is much larger than the vertical stress. The maximum principal stress is the horizontal stress and the minimum principal stress is the vertical stress. It agrees with the partial reasons of the mechanical principle of floor heave[12-14].Fig. 3 also shows that the variation is almost steady on the section x=when the working face advances 30 m. Therefore, the relationship of variation in stress with depth is calculated when the working face advances from 0 to 30 m. The details are shown in Table 1.Table 1 Data of rock characteristics and correlative stress of the floor on 2702 working face in Yangcun colliery (MPa)岩层深度(m)ΔλλΔx=0 m x=30 m x=30 m x=30 mλΔ泥岩0 37.50 0.00 0.00 0.00 37.500.4316.13 16.13 5 27.25 0.04 2.12 2.08 27.21 11.70 13.78砂岩10 22.53 0.28 3.83 3.55 22.250.327.12 10.67 15 19.95 0.77 4.91 4.14 19.18 6.14 10.28 21 18.17 1.46 5.40 3.94 16.71 5.35 9.29石灰岩25 16.75 2.21 5.46 3.25 14.540.284.07 7.32 28 15.55 2.94 5.24 2.30 12.61 3.53 5.83From the analysis of the related data, the stresses + λΔin Table 1 can be regarded as the stress values，obtained from mechanical rock tests. So the variations of the principal stress from theoretical calculations and the results from the servo-controlled tests can be contrasted. Given these contrasts it is seen that, the largest stress value of mudstone is 16.13 MPa and the largest stress value of sandstone10.67 MPa. When combining Fig. 5 with Table 1 it is seen that, the largest calculated principal stress is less than the peak value of the principal stress in Fig. 5, and the calculated section is at an elastic deformation section of Fig. 5, where permeability is relatively weak. So there is still a certain ability of water resistance. It can be shown that the obvious destruction is not produced in the mudstone and sandstone when the working face advances 30 m. This is essentially consistent with the conclusions of the survey report.4 Conclusions1) Based on the mechanical model of the floor, the analysis of stress distribution is obtained on the relatively fixed floor position with an advancing of working face. Owing to heterogeneity and discontinuity of the rock mass of the coal floor, there is a certain divergence between the ideal model and actual conditions. But from analyses and calculations, the basic variation law of stress distribution is discovered on the relatively fixed floor position with an advancing of working face when specific parameters are given for the working face.2) The decreasing rate of the vertical stress is faster than that of the horizontal stress up to a certain depth and the direction of the maximum principal stress is changed from vertical at the original position to horizontal with an advancing of the working face. The horizontal stress is larger than vertical stress within 42 m when the working face advances 30 m.3) The difference between the theoretically calculated principal stress and the results of the servo-controlled penetrability test can be contrasted. Deformation and penetrability can be obtained from the floor rock mass. From an example, it is seen that the mudstone and sandstone of coal floor are at an elastic deformation stage. There is no extreme destruction on the relatively fixed floor section with an advancing of working face and there still is a certain ability of water resistanceAcknowledgementsHere we express our sincere appreciation to director for Zhao Zhenzhong, minister Song Shun of Zhengzhou Coal Industry Group for their help during the course of the sampling. Appreciating Dr. Xi Yantao of China University of Mining and Technology for his help for modification.References：[1] Zhang J C, Zhang Y Z, Liu T Q. Rock Mass Permeability and Coal Mine Water Inrush.Beijing:Geological Publishing House, 1997. (In Chinese)[2] Miao X X, Lu A H, Mao X B, et al. Numerical simulation for roadways in swelling rock undercoupling function of water and ground pressure. Journal of China University ofMining and Technology, 2002, 12(2): 120-125.[3] Gong P L, Hu Y Q, Zhao Y S, et al. Three-dimensional simulation study on law of deformationand breakage of coal floor on mining above aquifer. Chinese Journal of Rock Mechanics and Engineering, 2005, 24(23): 4396-4402. (In Chinese)[4] Shi L Q, Han J. Floor Water-Inrush Mechanism and Prediction. Xuzhou: China University ofMining and Technology Press, 2004. (In Chinese)[5] Jing H W, Xu G A, Ma S Z. Numerical analysis on displacement law of discontinuous rockmass in broken rock zone for deep roadway. Journal of China University of Mining and Technology, 2001, 11(2): 132-137.[6] Liu Y D, Zhang D S, Wang Ii S, et al. Simulation analysis of coal mining with top-coal cavingunder hard-and-thick strata. Journal of China University of Mining and Technology,2006, 16(2): 110-114.[7] Dun Z L, Gao J M. Mechanics of Elasticity and Its Application in Geotechnical Engineering.Beijing: China Coal Industry Publishing House, 2003. (In Chinese)[8] Xu Z L. A Concise Course in Elasticity. Beijing: Higher Education Press, 2002. (In Chinese)[9] Liu W Q, Miao X X. Numerical analysis of finite deformation of overbroken rock mass in gobarea based on Euler model of control volume. Journal of China University of Mining and Technology, 2006, 16(3): 245-248.[10] Jiang F X. Rock Pressure and Stress Control. Beijing: China Coal Industry Publishing House,2004. (In Chinese)[11] Qian M G, Shi P W. Rock Pressure and Stress Control. Xuzhou: China University of Miningand Technology Press, 2003. (In Chinese)[12] Xu N Z, Tu M. The mechanism and control of floor heave of road driving along next goaf ofhigh seam. Journal of Anhui University of Science and Technology (Natural Science), 2004, 24(2): 1-4. (In Chinese)[I3] Wang W J, Hou C J. Study of mechanical principle of floor heave of roadway driving along next goaf in fully mechanized sub-level caving face. Journal of Coal Science and Engineering, 2001, 7(1): 13-17.[14] Zhai X X, Li D Q, Shao Q, et al. Control over surrounding rocks deformation of soft floorand whole-coal gateways with trapezoidal supports. Journal of China University of Mining and Technology, 2005, 15(2): 118-123.中文译文：采场底板岩层应力的分析模型及应用摘要：在分析矿山压力的基础上，运用弹性理论建立了煤层底板应力分析计算模型。
采煤专业毕业设计外文文献翻译--高效生产 — 一个关于采煤机截割的次序的问题
外文文献翻译英文原文High Productivity —A Question of Shearer Loader CuttingSequences1 AbstractRecently, the focus in underground longwall coal mining has been on increasing the installed motor power of shearer loaders and armoured face conveyors (AFC), more sophisticated support control systems and longer face length, in order to reduce costs and achieve higher productivity. These efforts have resulted in higher output and previously unseen face advance rates. The trend towards “bigger and better” equipment and layout schemes, however, is rapidly nearing the limitations of technical and economical feasibility. To realise further productivity increases, organisational changes of longwall mining procedures looks like the only reasonable answer. The benefits of opti-mised shearer loader cutting sequences, leading to better performance, are discussed in this paper.2 IntroductionsTraditionally, in underground longwall mining operations, shearer loaders produce coal using either one of the following cutting sequences: uni-directional or bi-directional cycles. Besides these pre-dominant methods, alternative mining cycles have also been developed and successfully applied in underground hard coal mines all over the world. The half-web cutting cycle as e.g. utilized in RA G Coal International’s Twentymile Mine in Colorado, USA, and the “Opti-Cycle” of Matla’s South African shortwall operation must be mentioned in this context. Other mines have also tested similar but modified cutting cycles resulting in improved output, e.g. improvements in terms of productiv-ity increases of up to 40 % are thought possible。
长壁式采煤法介绍外文文献翻译、中英文翻译
英文原文《Introduction of Longwall Mining》Executive SummaryLongwall mining is one of the principal underground mining methods in the United States. Its importance as a coal production technique has grown steadily since the introduction of modern longwall technology into this country in the 1950's and 1960's. In the past decade longwall production and productivity grew rapidly, as a result of significant improvements in longwall equipment and operating practices. By 1993, longwall mining accounted for 40 percent of the Nation's underground coal production—up from 27 percent in 1983. Labor productivity at longwall mines more than doubled between 1983 and 1993. Productivity is now higher for longwall mining than for other underground production methods, and productivity is expected to keep g rowing as new technological advances are introduced.Longwall mining is one of two basic methods of under ground coal mining. The other method is room-and-pillar mining, historically the traditional method used in the United States. In room-and-pillar mining, “rooms” are excavated, and pillars of coal are left in place between the rooms to support the mine roof. In contrast, longwall mining involves the essentially complete extraction of the coal contained in a large rectangu lar block or “panel” of coal, and the roof in the mined-out area is allowed to collapse.The sequence of operations in longwall mining is basi- cally simple. The rectangular longwall panel, averaging nearly 800 feet wide, 7,000 feet long, and 7 feet high, is “blocked out” by excavating passageways around its perimeter. Room-and-pillar mining is used to block out the panel. Excavation of the coal in the panel is an almost continuous operation. Working under the steel canopies of hydraulic, movable roof supports, a coal cutting machine runs back and forth along the 800-foot face, taking a cut ranging anywhere from a few inches to 3-1/2 feet deep during each pass. The cut coal spills into an armored chain conveyor running along the entire length of the face. This face conveyor dumps the coal onto belt conveyors for transport out of the mine. As the cutting machine passes each roof support, the support is moved closer to the newly cut face to prop up the exposed roof. The roof is allowed to collapse behind the supports as they are advanced towards the face. Mining continues in this manner until the entire panel of coal is removed.Because longwall mining is essentially a continuous, highly mechanized operation, longwall productivity is potentially higher than room-and-pillar productivity. Longwall mining also offers improved safety through better roof control, more predictable surface subsidence, and better opportunity for full automation. Onthe other hand, capital costs for longwall equipment are much higher than for room-and-pillar equipment, productivity during development (“blocking out”) of the longwall panels is typically low, and large amounts of dust and methane are generated during the mining process.IntroductionLongwall mining is one of the principal underground mining methods in the United States. In 1993,longwall mines accounted for 40 percent of the Nation's under-ground coal output—compared with 27 percent in 1983. Although basic longwall mining techniques were de- veloped in England in the 17th century, there was little interest in longwall mining in the United States until the 1950's, when new German technology was introduced. As the technology was developed further in the United States, longwall production grew steadily. By 1993, 85 longwall units were operating in 12 States. Labor productivity at longwall mines more than doubled between 1983 and 1993. Productivity is now higher for longwall mining than for other underground production methods, and productivity is expected to keep growing as new technological improvements are introduced. The purposes of this report are to describe the longwall mining process, analyze the most important changes in longwall mining over the past decade, and discuss factors that will shape the future of longwall mining.The History of Longwall MiningLongwall mining is not a new approach to coal mining.In fact, the basic principles of longwall mining have beentraced back to the latter part of the 17th century to Shropshire and other counties in England, where it was described as a “totally different method of mining” called the “Shropshire method.” Many modifications in the original methods have occurred, but all longwall mining has involved extracting coal from a long wall or face. The area from which the coal was ext racted, the “gob” (from a Celtic word for cave or hollow), was partly or wholly filled with stone and refuse, upon which the overlying strata settled.Until the early 1900's, coal mining in England was mostly by the “bord and pillar” method (equivalent to “room-and-pillar”). The “bords,” or passages, were areas 12 to 20 feet wide from which the coal was extracted; the pillars were made of coal, some 50 feet wide and as many as 100 feet long, that was left unmined to support the overlying strata. Efforts to extract some or all of the coal left in the pillars at a later stage of mining either were not attempted or were not always successful As the demand for coal increased, bord and pillar mining soon was regarded as wasteful, and the advantages of the longwal l technique were noted: “It enables a colliery to be opened with less capital expenditures . . . and to become remunerative in the smallest possible time . . . The yield per acre is greater . . . Ventilation is easier,the workmen are concentrated, and the expense of supervision is reduced . . . in seams giving off large quantities of explosive gas . . . shot firing can almost entirely be dispensed with [because the] weight on the face is in itself sufficient to bring down the coal”The overall layout of early longwall mines was generally circular, with mining radiating out from a central shaf. The main roadways ran diagonally from the shaft pillar like the spokes of a wheel, while the intervening areas were subdivided into smaller and smaller sectors by subsidiary roadways. The roadway were kept open by “pack walls” of waste rock constructed on either side of them. The roof in the working area, or face, was supported by a line of timbers, which were moved forward as mining advanced, and by “packs” or “cribs” of waste rock, while the roof in the mined out area was allowed to collapse.Longwall mining was practiced on a very small scale in the United States in the late 1800's and early 1900's. The pioneering longwall attempts were generally in thin coalbeds that could not be mined effectively by room-and-pillar techniques, and that required a minimum of packwall construction and backfilling for roof support. Where successful, those early longwall operations resulted in complete removal of the coal at minimal expense, with less timbering, more controlled subsidence, and better ventilation in the working area than room-and-pillar methods.Until undercutting machines became available in the early 1900's, longwall miners undercut the coal by hand with picks. The early working faces generally were in the form of an arc about 40 feet across, but as mines became deeper and mechanized, straight faces were found to be more efficient.The undercut coalbed was temporarily supported by short wooden props or “sprags” set ev ery 4 to 6 feet. When the props were knocked out, the undercut coal fell because of its own weight and roof pressure, but if necessary, it was knocked down; explosives were seldom used. The broken coal was then loaded by hand into cars (tubs) for transport out of the mine. By 1924, productivity was improved when conveyors were installed along the longwall face in some mines.Overall, the experience of early longwall mining in the United States showed that it was not competitive with the room-and-pillar method. Although steel jacks replaced wooden props for roof control around 1912, and mines were becoming mechanized, the large number of workers required to move the jacks and to construct other types of roof supports made longwall mining a labor-intensive effort. With longwall productivity averaging only about 3 tons or less per worker per shift, U.S. underground mining technology focused on improving room-and-pillar mining, a better method for extracting coal from relatively thick beds. In contrast, longwall mining remained predominant in Europe, where conditions were more suitable for thetechnique because the coalbeds were deeper and overlain by thinly layered strata that caved more easily than those in the typical U.S. coal mine.1950-1960After World War II, U.S. interest in longwall mining was renewed by the possibilities of using the German developed plow (or planer) and “panzer,” or armored face conveyor. The plow is pulled across the coalface while riding on a base that slides under the conveyor. It shaves off 2 to 4 inches of coal that spills onto the conveyor. In 1952, Eastern Gas and Fuel Associates, with support from the U.S. Bureau of Mines, tested longwall mining with a plow and face conveyor at the Statesbury mine, near Beckley, West Virginia, to learn if this type of equipment could be used to extract some U.S. coal. Roof support was provided by mechanical props with I-beam caps and wood cribs. The test was successful and the equipment was used in three other longwall operations between 1952 and 1958.During the 1950-1960 period, there were an average of six longwall operations per year, mostly in West Virginia and Pennsylvania, but also in Arkansas. The plow was he principal coal-cutting machine, replacing the early labor-intensive mechanical undercutting method. However, about three-fourths of the longwall operations were not successful because the coalbeds were not friable enough for extraction with a plow, or because roof control presented problems.Although the hydraulic props introduced in the late 1950's were an improvement over the earlier mechanical friction props, a large amount of manual labor was still needed to recover and reset the props. Moreover, as the face advanced, wood cribs had to be constructed for additional roof support, requiring additional manual labor. As a consequence, by 1960 longwall mining was generally considered a last resort, used only for extracting thin beds of premium coal when room-and-pillar methods failed. Other factors also constrained the use of longwall mining in the United States. These included the lack of familiarity with the method on the part of the U.S. coal industry, and the high capital investment required for the equipment. Furthermore, by this time, continuous mining machines were improving the efficiency of room-and-pillar mining.1960-1970Interest in longwall mining in the United States revived in the 1960's, and the number of installations rose to about 20 before 1970, due mainly to the introduction of self-advancing hydraulic roof supports. These powered supports replaced jacks and wood cribs, eliminating the need for substantial labor. They also had the advantage of being able to push the conveyor forward automatically as the face advanced. Self-advancing hydraulic roof supports were first used, together with a plow, in 1960 to excavate a 52-inch coalbed in Eastern Associates' Keystone mine near Welch, WestVirginia.The first self-advancing roof supports were frames. A frame consisted of two single hydraulic jacks connected to a beam, and two frames were linked together to operate as a pair. They advanced in two steps. While one frame remained set between the roof and floor, the other was lowered and then pushed forward by a ram; the procedure was reversed to move the other frame. Frames with a two-leg design could support as much as 88 tons before yielding; those with four-leg designs were about twice as strong.Frames successfully supported the roof when the overlying strata caved easily, but they were often inadequate if the strata “hung up.” A number of longwall installations in the Illinois Basin were discontinued because frames could not control the mine roof.In the mid 1960's, better designed, high-capacity, self- advancing roof supports, capable of holding about 700 tons, became available in the form of the chock. Described as a mobile crib, the chock consists of two frame supports tied together with a rigid canopy and semi-rigid base. More stable than frame supports, the chock is also safer because it has a canopy that provides protection against material falling from the mine roof. The chock can also be advanced as a single unit by a hydraulic ram attached to the face conveyor.Although the chock represents a great improvement in roof control technology, it can become unstable when the roof caves in large pieces and creates rotational or horizontal stresses. The instability can occur because the chock's canopy is connected to its base only by the hydraulic leg cylinders. Several longwall operations in southern Illinois were abandoned because chocks failed as the result of serious roof control problems.The 1960's also saw the introduction of the shearing machine in the United States, first at Kaiser Steel Corporation's Sunnyside mine in Utah in 1961, and later in mines in the East. The shearing machine is an electrically powered rotating drum that not only excavates harder coal, but also cuts a wider strip (24 to 28 inches) from the coalbed than the plow.However, the early shearers were not free of problems. A shearer's performance could be reduced if the supports were not advanced uniformly, resulting in poor alignment of the shearer with the coal face. Furthermore, the shearer's heavier weight required the use of stronger armored face conveyors to support it. Shearers also produced finer sized coal than plows, and this tended to jam face conveyors, reducing productive mining time. Health problems became a concern because the shearer also generated more respirable dust. Nevertheless, by 1966, after improvements were made, shearers produced 42 percent of the coal at U.S. longwall operations. By 1970,shearers outnumbered plows, and the first double drum ranging shearer was in service in the northern Appalachians.1970 to 1980In this period, the last major impediment to the acceptance of longwall mining in the United States was overcome through the introduction of shield supports, a major step in the evolution of roof control. Although new to the U.S. coal mining scene, shields had been used successfully since the 1960's in the Soviet Union and ther Eastern European countries.Safety and productivity factors favored the shield over the chock. The average support capability of a shield and chock are about the same, but the shield is more stable. The shield provides additional roof support because its canopy and base are connected by structural members other than the hydraulic leg cylinders. As a result, the leg cylinders of the shield, unlike those of the chock, are not subjected to damaging bending movements.The first shields in the United States were installed in 1975 in the Shoemaker mine of Consolidation Coal Company, near West Virginia. Shortly afterwards, shields were applied to other U.S. longwall operations, proving successful in areas where other roof supports failed. The basic shield design was improved, and by the late 1970s, shields were the leading roof supports in longwall installations.Advances made to the double-drum and ranging arm shearers developed in the 1960's made them more adaptable. Their cutting height could be quickly adjusted when coalbed thickness changed or when it was necessary to leave a layer of coal at the top of the bed to strengthen the mine roof. Improvements were also made in the method of hauling the shearer across the coal face. The early shearers were pulled by chains stretched along the length of the face. If the chain broke, it could cause serious injuries. By the early 1970's, shearers moved by safer “chainless” methods using self-contained traction units. Although development concentrated on the shearer, the plow was also improved. A plow designed to be stronger and more rugged was placed in service in 1974 at Clinchfield Coal Company's No. 2 mine, near Dante, Virginia. It operated successfully in a thin coalbed that had been too hard for earlier plows.1980-1994Since 1980, an average of more than 100 longwall installations have been in operation annually in the United States. In recent years, however, the number has declined slightly, reflecting partly economic and market conditions for coal and partly the ability of the current longwall operations to meet demand without the need for additional installations.Shields have become the predominant type of roof supports in U.S. longwall mines, and shearers the principal cutting machines. The reliability of armored faceconveyors, like that of roof supports, has been improved to the extent that they are no longer responsible for major interruptions in longwall mining.The list of wide-ranging advances in longwall technology includes shearers that are designed to mine relatively thin coalbeds (less than 42 inches). Better dust control has been achieved with water sprays and improved design of cutting drums and cutting bits. Power supply problems for large multiple shearer motors and longer face conveyors have been overcome.Because longwall mining is a repetitive process, it has the potential to be automated. Among the health and safety benefits from an automated longwall installation are the removal of personnel from hazards such as dust exposure, roof falls, and noise. The economic benefits include improved coal quality, higher productivity, reduced maintenance costs (for example, reduced wear on the shearer's cutting bits), increased speed of operation, and better use of personnel.Automation is being incorporated in all phases of longwall mining. Push-button control to begin a sequence of predetermined patterns is now becoming the norm. Shield advance can be automatically controlled by a signal from the shearer. Sensors and control systems have been developed to detect the coal-rock interface and provide automatic vertical ranging of the shearer drums.An example of the mature state that longwall mining has reached is the 15-million dollar system installed by the CONSOL Coal Group in 1994 at its Robinson Run mine, near Shinnston, West Virginia. Reportedly the world's most advanced longwall system, it integrates sophisticated computer technology, instrumentation, and robotic controls to automate most of the routine tasks of longwall mining, using a 42-inch coal shearer and 172 hydraulic roof support shields.Longwall Mining Compared with Other Underground Coal MiningTechniquesLongwall mining is one of two basic methods of mining coal underground. The other is room-and-pillar mining, historically the standard method in the United States. Both of these methods are well suited to extracting the relatively flat coalbeds (or coal seams) typical of the United States. Although widely used in other countries, longwall mining has only recently become important in the United States, its share of total underground coal production having grown from less than 5 percent before 1980 to 40 percent in 1993. 1 Currently, 85 longwalls operate in the United States, most of them in the Appalachian region.The basic principle of longwall mining is simple. A coalbed is selected and blocked out into a panel averag- ing nearly 800 feet in width, 7,000 feet in length, and 7 feet in height, by excavating passageways around its perimeter. A panel of this size contains more than 1 million short tons of coal, most of which is recovered. In theextraction process, numerous pillars of coal are left untouched in certain parts of the mine in order to support the overlying strata. The mined-out area is allowed to collapse, generally causing some surface subsidence.Extraction by longwall mining is an almost continuous operation involving the use of self-advancing hydraulic roof supports, a sophisticated coal-shearing machine, and an armored conveyor paralleling the coal face. Working under the movable roof supports, the shearing machine rides on the conveyor as it cuts and spills coal onto the conveyor for transport out of the mine. When the shearer has traversed the full length of the coal face, it reverses direction (without turning) and travels back along the face taking the next cut. As the shearer passes each roof support, the support is moved closer to the newly cut face. The steel canopies of the roof supports protect the workers and equipment located along the face, while the roof is allowed to collapse behind the supports as they are advanced. Extraction continues in this manner until the entire panel of coal is removed.By contrast, the typical underground U.S. coal mine is laid out in a checkerboard of rooms and pillars, and the mining operation involves cyclical, step-by-step mining sequences. The rooms are the empty areas from which coal has been mined, and the pillars are blocks of coal (generally 40 to 80 feet on a side) left to support the mine roof. Room-and-pillar mining generally is limited to depths of about 1,000 feet because at greater depths larger pillars are needed, resulting in smaller coal recovery.The “continuous” version of room-and-pillar mining is the most common, representing 56 percent of all underground production in 1993. In this method, a con- tinuous mining machine excavates the coal and loads it onto a conveyor or shuttle car in a single step. Despite the term “continuous,” the machine operates only part of the working time, because after mining advances about 20 feet, the machine is withdrawn from the face so that roof bolts can be installed to bond the strata and prevent caving.In “conventional” room-and-pillar mining (which rep- resents 12 percent of underground production), production occurs in five steps: mechanically undercut- ting the coalbed, drilling holes into the bed for explosives, blasting the coal, loading the broken coal into shuttle cars for delivery to a conveyor, and then bolting the mine roof in the excavated area.To provide a steady flow of coal in a room-and-pillar mine, several stages of mining occur simultaneously in different rooms. A final phase of mining termed “retreat mining” may be performed to recover additional coal by extracting pillars and allowing the roof to fall. However, this is a complex procedure that requires additional planning.Advantages of Longwall MiningLongwall mining is a very efficient coal-producing technique. Longwallproductivity is potentially higher than that of room-and-pillar mining, because longwall mining is basically a continuous operation requiring fewer workers and allowing a high rate of production to be sustained. The amount of coal recovered is also high, currently reaching 57 percent as a nationwide average, but achieving higher percentages at some mines. Room-and-pillar recovery rates are slightly lower. However, longwall coal recovery may not be significantly different from room-and-pillar mines prac-ticing “retreat mining.”The longwall system also offers a number of other advantages over room-and-pillar mining. It concentrates miners and equipment in fewer working sections, making the mine easier to manage. Safety improves through better roof control and a reduction in the use of moving equipment. This method eliminates roof bolting at the working face to support the mine roof, and it minimizes the need for dusting mine passages with inert material to prevent coal dust explosions. It involves no blasting, with its consequent dangers. It also recovers more coal from deeper coalbeds than does room-and-pillar mining. The coal haulage system is simpler, ventilation is better controlled, and subsidence of the surface is more predictable. Overall, as well, longwall mining offers the best opportunity for automation.Disadvantages of Longwall MiningForemost among longwall mining's drawbacks are capital costs for equipment and installation that are substantially higher than those for room-and-pillar mining. In addition to longwall equipment, continuous mining machines and other equipment used in room-and-pillar mining arerequired for the development work needed to block out a panel of coal for longwall mining. Because a large initial capital outlay is required with no immediate return from coal production (apart from the coal produced during development work), economics generally restricts longwall mining to large coal companies. Moreover, small coal companies inexperienced in longwall mining may not be able to provide time for the specialized training needed for this mining method.Longwall mining is a method in which all parts must operate as an integrated system. A failure of one part can disrupt the entire operation, and the impact on meeting contracts for coal sales can be substantial.Longwall mining also requires a well-maintained ven- tilation system because of the large amounts of dust and methane produced. Dust levels often exceed the maximum allowable limit despite improvements in dust-control technology. When this is noted during a Federal mine inspection, a temporary variance is granted so that the dust levels can be lowered by modifying the coal-cutting sequence and/or by increasing the air flow across the face.Changes in Longwall Mining Over the Past DecadeAs of 1993, a total of 85 longwall units operated in 73 U.S. coal mines. Most of these mines (53) were located in Appalachia. West Virginia was the leading longwall State, with 21 mines. In 1993, there were 13 longwall mines in the West and 7 operations in the Illinois Basin. Relative to the total underground mine population of roughly 1,200 mines, the longwall mine population is quite small.However, because longwall mines are almost invariably large operations with high annual production rates, their share of total underground production is dispropor-tionate to their small numbers. In 1993, 40 percent of the total U.S. underground coal output was produced at longwall mines. This was considerably higher than the 27-percent production share contributed by longwall mines in 1983. Longwallmines now account for 80 percent of underground production in the West, 37 percent in Appalachia, and 27 percent in the Illinois Basin.The rise in longwall production was largely due to a dramatic increase in longwall labor productivity. Between 1983 and 1993, the average productivity at U.S. longwall mines increased 108 percent, from 1.59 tons to 3.30 tons per worker-hour. Although the productivity of room-and- pillar operations also increased rapidly during this period of declining coal prices and highly competitive markets, operators of room-and-pillar mines were not able to keep pace with longwall operators. As a result, average longwall labor productivity, which was 2 percent lower than the average productivity of room-and-pillar mines in 1983, became 19 percent higher than room-and-pillar productivity by 1993.There are considerable regional differences in longwall mining productivity. In the West, where the coal seams are substantially thicker and less gassy than in other regions, longwall mining leads other mining methods by a wide margin in terms of productivity. In 1993, western longwall productivity stood at 5.67 tons per worker- hour—40 percent higher than the productivity of continuous miner operations (the prevalent type of room- and-pillar operation). However, in the Illinois Basin, the productivity differential between longwall and contin- uous mining was insignificant; and in Appalachia, longwall mines had only a 7-percent productivity advantage over continuous mining operations (2.94 tons per worker-hour versus 2.76 tons per worker-hour). In part, this may be because Appalachian longwall mines, producing high-quality coal for metallurgical and export markets, use additional resources for coal cleaning and preparation—processes that reduce the final coal output.If longwall mines do not have a pronounced productivity advantage over continuous miner operations in the Illinois Basin and Appalachia, why has longwall mining achieved significant market penetration in these regions over the past decade? One possible reason for the trend toward longwall mining is that it has greater potential than other underground mining methods for future productivity。
矿井提升机中英文对照外文翻译文献
(文档含英文原文和中文翻译)中英文资料对照外文翻译英文原文Study of Inherent Safety Mine hoist based on modern designmethodsAbstract—As a modern security design, Inherent Safety means that equipment and facilities is able to contain the inherent fundamental features to prevent accidents. Mine hoist is the most important equipment in the coal production. How to achieve safe, reliable, efficient production has been the focus study at home and abroad. Inherentsafety is reflected in hoist design, primarily through the design measures to improve the operation of hoist safety and reliability. In this paper, Inherent Safety theory is applied in the design of mine hoist, to proposed the design method by using the software of PRO/E PLC, Labview etc..Keywords-Mine hoist; Inherent Safety; PRO/E; PLC; LabviewI. INTRODUCTIONIn coal production, mine hoist is the equipment to carry coal, gangue, materials, workers and equipments along the rockshaft, the only way linked underground and aboveground, known as mine throat. Mine hoist is a large-scale reciprocating machinery which has the feature of own big inertia, load changes, running speed, and wide range et al.. The advantages and disadvantages of its operating performance, not only directly affect the normal production and coal production efficiency, but also relate to equipment and personal safety. In recent years, mine hoist failures and accidents have happened at home and abroad which have paid a heavy price to coal companies. Therefore, the production technology and safety of mine hoist are higher, and its mechanical manufacturing technology and electrical control technology has been an important research area to the international machine building industry and the electric control industry.Inherent Safety means that equipment and facilities is able to contain the inherent fundamental features to prevent accidents. Inherent Safety lies in design, through continuous improvement, to prevent accidents due to the equipment itself failures. Inherent safety is reflected in hoist design, primarily through the design measures to improve the operation of hoist safety and reliability. In this paper, Inherent Safety theory is applied in the design of mine hoist, to proposed the inherent safety design method by use the software of PRO/E PLC, Labview etc..II. INHERENT SAFETY THEORYThe term of inherent safety originates the development of world space technology in the 1950s. The concept is widely accepted closely linked with scientific technological progress and human understanding of safety culture. The concept of inherent safety produced after the World War II which became major safety concept in many industrialized countries since the mid 20th century.Inherent safety design as the basic method of hazard control, by selecting safe materials, process routes, mechanical equipment, devices, to eliminate or control hazards source rather than relying on "additional" security measures or management measures to control them. As inherent safety design, firstly analyze and identify hazards that may occur in system, and then choose the best methods to eliminate, control hazards, which reflected in project design.Ⅲ. THE DESIGN OF INHERENT SAFETY MINE HOISTMine hoist mainly includs the working device, control system, transmission system and drag, protection systems and other components. To the inherent safety mine hoist design, mainly the mechanical system, control system and monitor system is the major part to considered.A.In-depth investigations to find malfunctionThe concept of inherent safety is required safety all the time in the product design process. That is, the equipment has little malfunction as much as possible during the operation and has long normal operation cycle length. How can design inherent safety equipment, the most important thing is understanding enough to the equipment, especially in work. After in-depth research, fully understanding the situation, try the best to reduce or eliminate the fault in the design. After in-depth understanding of research, design product.B. Mechanical SystemThe traditional method of product has long design cycle, high costs. However, the virtual prototype technology has the advantage in saving the design cost, shortening the design circle, by using the method of modeling, simulation first and then builds the physical prototype. Therefore, the virtual design is the developing trends of mechanical design. In mechanical system design, the application of virtual prototype is used to design mine hoist, not only speeded up the design process, also simulated a variety of conditions to the virtual prototype to discover design faults, to improve the design, to improve mine hoist performance.Mine hoist mechanical system is composed of spindle, roller, reducer, motor, brakes and other components. In its design, virtual design software PRO / E is applied to establish hoist prototype, application of simulation software ADAMS is used to simulate and optimize the design. Specific process shown in Figure 1:Figure 1. Mechanical system designC. Control system designMine hoist control system includes start, run, brake, etc., the requirements in control system are:In normal hoist operation, participation in hoist speed control, brake the hoist when reaching the destination, known as the service braking;In case of emergency, can quickly slow down as required, brake hoist, to prevent the expansion of the accident, that is the safety braking; Participate in the hoist speed control when decelerati; To double-roller hoist, should brake the moving roller and fix roller respectively when regulating rope length, replacement level and changing rope, so that, moving roller would not move when spindle rotates with the fixed roller.Most of mine hoists in China (more than 70%) use the traditional electric control system (tkd-a as the representative). Tkd control system is composed of relay logic circuits, large air contactors, tachometer generator etc., which is a touch control system. After years of development, tkd-a series of electric control system has formed its own characteristics, but its shortcomings are obvious. Its electrical circuit is too complicated, multi-line, causing hoist parking and accidents occurred due to electrical fault. With the computer and digital technology, to form a digital hoist control systemof PLC has become possible. PLC control system has high control precision, parameter stability, simple hardware structure, self-diagnostic capability and communication networking function.Mine hoist control system based on PLC technology structure shown in Figure 2, mainly including the following components: the main plc control circuits, hoist route detection and display circuits, speed detection, and signal circuits. The PLC of the main control circuits uses Mitsubishi FX2N series in Japan which more domestic applications.Figure 2 PLC electric control systemD. Monitoring system designTo ensure safe operation of the hoist, except for selecting the reasonable operation design parameters, the use of advanced control system, should also monitor the technological parameters on regular, conscientiously do performance test work to master the hoist performance,discover the defects in time, eliminate hidden danger, avoid unnecessary losses. In addition, the hoist operation state can be improved to work in the best conditions based on test data. Therefore, the hoist could work safely, reliably, have high efficiency, and extend its work life.Virtual instrument technology is computer-based instrumentation and measurement technology, is loaded some software and hardware on the computer with similar appearance and performance of the actual independent instrument. The user operating the computer, like manipulating a especially conventional electronic devices designed theirs. The essence of virtual instrument technology is that hardware softwarized technology, take full advantage of the latest computer technology to implement and expand the functions of traditional instruments.LabVIEW (laboratory virtual instrument engineering workbench) is a graphical programming and development environment, also known as "G" language. It is widely used by industry, academia and research laboratories, accepted as the standard data acquisition and instrument control software. LabVIEW not only provides and complies with all the functions of hardware and data acquisition cards communications of GPIB, VXI, RS-232 and RS-485 protocol, and built-in library functions support for TCP / IP, ActiveX and other software standards. The software for scientists and engineers is a programming language, it provides a simple, intuitive graphical programming mode, saves a lot of development time, has complete function, best embodied style of virtual instrument.In response to these circumstances, developed a mine hoist Integrate Performance Monitoring System based on virtual instrument LabVIEW-based. Show in Figure 3. With signal conditioning and data acquisition card to receive signals from sensors, then sent the received signal to the virtual instrument software platform, enables the following features: （1）show speed, acceleration, braking time, displacement, oil pressure, delay time and other relevant parameters in digital, and display speed, acceleration, traction, displacement and hydraulic curves.（2）Dynamically monitor the hydraulic oil pressure and oil pump running station, based on these parameters to avoid important braking system failure.（3）Test brake air travel time, relay delay time and other time parameters.（4）inquiry to the measured curve and hoist parameters; print a testreport.Figure 3. Diagram of test systemThe monitoring system has characteristics such as compact, light weight, high precision, testing convenient and flexible, feature-rich software etc.. the system can not only display automatically test results, but also finish multiple functions, for example , data transmission, analysis, processing, storage and report printing. The system is high precision, can easily monitor the hoist operation state, to ensure the reliability of hoist operation.Ⅳ. CONCLUSIONSIn this paper, used virtual design software to design the hoist mechanical system, PLC to design control system, applied virtual instrument software-LABVIEW to design monitor system. Therefore, the mine hoist designed has good mechanical properties and safe operation, monitoring easy.REFERENCES[1] Weng qishu. The inherent safety and checks of cabin[J]. navigationTechnology 2006 (3):50-52. (in Chinese)[2] Li jangbo. Study of Test System of Composite Characteristic of Devices Based onVirtual instrument[D]. A Dissertation Submitted to Hebei University ofEngineering For the Academic Degree of Master of Engineering, 2007. (inChinese)[3] Wang chengqin, Li wei , Meng baoxing et al... Random vibration testing system ofhoisting gear based on virtual instrument. Coal mine machinery, 2008(4) :118-120.(in Chinese)[4] Chen baozhi Wu min. concept and practices of inherent safety[J]. Journal ofSafety Science and Technology,2008(6):79-83. (in Chinese)[5] Xu chenyi, Wu yongdong, Huanghe et al.. A PLC-based mine hoist control systemdesign [J]. LC&FA, 2008(10):52-56 (in Chinese)中文译文基于现代设计方法的矿井提升机内在安全性的研究摘要：作为一个现代的安全设计，内在的安全性意味着设备和设施能够包含防止事故发生的固有基本特征。
采矿山机电设备制造外文文献翻译、中英文翻译、外文翻译
附录：河南理工大学万方科技学院本科毕业设计外文资料与中文翻译院（系部）机械与动力工程系专业名称机械设计制造及其自动化年级班级0 8级机设5班学生姓名周杨指导教师李延锋2012年5月15日外文资料与中文翻译外文资料:China is a mining power and mining equipment manufacture and use of mechanical and electrical power.From the 20th century,modeled after the 50's the first since the mine hoist has been designed and manufactured,used more than 6,000. With the needs of the community and the rapid development of technology,mining industry production equipment and facilities need to mechanization,electrification,The mining industry is the throat of the elevator equipment,replacement products,old products long time run,the structural problems behind the original exposed prominent fault more serious impact on the safety of mining operations,curb the rapid development of mining industries to the national economy with to the adverse effects.With the ever-changing mine to increase production ,upgrade the machine to improve safety,of machine to run automated,reducing operation and maintenance of the labor intensity,the speed of of the accident and so on,into the urgent requirement.Mine hoist for renovation,is extremely important. For example,wood lining hoist drum serious wear and tear,when the trees lining up to a certain degree of wear and tear on the lining must be replaced wooden reel,or a security incident is likely to affect the safety in production.Andreplacement of wooden drum liner is a very cumbersome process,while the high cost of wood lining reel,high maintenance costs, maintenance time.Consume a large amount of manpower,material and time at the same time,and affects the security of the entire mine production and demand for production,to that end, the design of a reel turning wood lining device is a very necessary technology.As a result of taking into account the existing trees lining reel slot car there are many devices deficiencies,the paper lining from the existing wooden reel slot cars of the principle of analyzing devices,wear and tear on wire rope of research,the role of drum parts and the forces analysis of the existing car tank equipment to improve processing methods and applications,based on the user-friendly, effective and practical under the premise of turning wood on the drum liner device was designed to maximize the improvement of steel wire rope and reel service life of wood lining and reduce production costs and shorten the processing and maintenance cycle,reducing the labor intensity.Through constantly improving and perfecting the design of the drum lining wood turning can be a convenient device for turning wood drum liner,the installation of wire rope to reduce wear and tear,but also extended the service life of wooden drum and the lining can produce a substantial savings cost.HKM2×4×1.8-based transformation of hoistJiaomei jiulishan mine hoist HKM2×4 ×1.8 Department of the former Soviet Union and type of products manufactured in the50's,the reel structure of a typical shell thick branch. Put into use since 1963 until now,has been running for 47 years,for a total of about 64 million out of coal t.With the increasing production to meet the needs of the mine production in 1982 had a greater technological innovation,the annual output from 1,200,000 t to 1,800,000 t. Enhance the increase in weight as a result of running some time after percutaneous invagination and open reel welding,crack phenomenon. Also in 1985 inside the drum in two directions along the circumference,respectively,an increase of the I-11 # 2,to increase the support drum,to try to resolve open reel reel welding and the phenomenon of skin retraction.However, after running for some time, the support drum parts and drum skin open welding,the cracks gradually serious phenomenon,there are four supported I-beam 3 has a horizontal fracture,open reel welding vice 21,all four I-beam horizontal fracture.In order to ensure safety in production,we have adopted a variety of methods,such as an increase to strengthen the board,direct welding, hit 45 ° groove welding, welding,after annealing,and so will not solve the problem of DC welding,but welding arising as a result of repeated stress concentration,so that Open welding phenomenon more serious run-time hoister abnormal dislocation metal sound, has seriously affected the security of the entire mine production.In order to ensure safety in production, production management group and the jiulishan mining joint research,the status quo through the survey and found that the existence of the following issues:1.Invagination serious skin drum,about 10~12mm,resulting in severe deformation of wood lining,the sound of running.2.Lord, Vice-reel wood lining wear inconsistent,resulting in the main,the Deputy reel run that is inconsistent paragraph rope wrapped around the lame often said,resulting in loading,unloading difficulties.3.Reel support I-beam and drum parts are cracking skin serious run soon after welding cracks,and cracks have been increased and extended. Is the main,the Deputy reel 8 to support the horizontal I-beam are broken,cracks in skin reel has been extended to drum brake wheel, hoist the wrong run-time anomalies metal sound.4.The high maintenance costs.Reel hoist wood lining must be replaced once a year,each to be 24h,the material consumption for 35,000 yuan.5.Repair time.Reel monthly reinforcement welding carried out in more than 16h,consume a large amount of manpower,material and time. Due to these aspects of the fault,resulting in the normal operation of hoist can not be seriously affected the security of the entire mine production and demand for production,for which a technological transformation of the reel.Rehabilitation programsAs the replacement cost of the elevator and the time too long,not in conformity with the actual scene,after full investigation, research and feasibility analysis,we have decided to upgrade the existing machines on the basis of the transformation,that is,to keep the original motor, speed machine,the braking system,the spindle and spindle support device round, the replacement of the main,the Deputy reel and reel spokes.The use of the new reel CITIC Heavy Machinery Company with a fixed rope groove, the structure of the reel one,two and a half of each reel by the reel of the drum skin is 40mm thick rolled steel plate 16Mn,tungsten above have fixed rope groove,which is a weak branch structure Cryptocarya high-strength roll.Drum replacement program and a key link:(1)The new reel will be processed to the scene,(2)Installed in the garage outside the drilling of two in order to field drilling,(3)Crane transform garages, walk in part by the manually read electric,(4)The laying of railway, from the bus garages Shop Housing, in order to save time for the delivery drum,(5)Preparation of a cable car, the garage is responsible for the lifting of work outside the drum,(6)Principal, vice skip on the wellhead,(7)Hoist to remove the gate and gate post,(8)Spoke to the old Office disconnected from the reel, cut in half, were transported onto the Housing(9)New drum hanging in place, the scene is looking for its eyes. And then transported onto the room, eyes drilling with drilling, (10)through eyes will be hanging a new reel in place, Reaming and bolts,(11)Field testing of the hoist at all stages of technical parameters and characteristics,(12)Pile gate and gate installation and test on the ropes。
采煤采矿采煤机外文文献翻译、中英文翻译、外文翻译
附录A简介：煤炭是我国的主要能源，在我国一次性能源中占76％以上。
煤系地层大多形成与还原环境，煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，使水呈酸性，形成酸性矿井水。
对地下水以及其它环境和设施等造成一定的环境影响和破坏。
本文对酸性矿井水的危害、形成原因以及对酸性矿井水的预防和治理进行了简单的阐述。
关键字：采煤活动酸性矿井水环境影响预防治理1前言煤炭是我国的主要能源，在我国一次性能源中占76％以上，必定要进行大量的采煤。
采煤过程中破坏了煤层所处的环境，使其原来的还原环境变成了氧化环境。
煤炭中一般都含有约0.3％～5％的硫，主要以黄铁矿形式存在，约占煤含硫量的2/3。
煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，生成硫酸和氢氧化铁，使水呈现酸性，即生产了酸性矿井水。
PH值低于6的矿井水称酸性矿井水。
酸性矿井水在我国部分煤矿特别使南方煤矿分别较为广泛。
我国南方煤矿的矿井水pH值一般在2.5～5.8，有时达2.0。
pH值低的原因与煤中含硫量高有密切关系。
酸性矿井水的形成对地下水造成了严重的污染，同时还会腐蚀管道、水泵、钢轨等井下设备和混凝土井壁，也严重污染地表水和土壤，使河水中鱼虾绝代，土壤板结，农作物枯萎，影响人体健康。
1 酸性矿井水的危害矿井水的pH值低于6即具有酸性，对金属设备有一定的腐蚀性；pH值低于4即具有较强的腐蚀性，对安全生产和矿区生态环境产生严重危害。
具体有以下几个方面：1>腐蚀井下钢轨、钢丝绳等煤矿运输设备。
如钢轨、钢丝绳受pH值<4的酸性矿井水侵蚀，十几天至几十天其强度会大大降低，可造成运输安全事故；2>探放pH值低的老空水，铁质控水管道和闸门在水流冲刷下腐蚀很快.3>酸性矿井水中SO42-含量很高，与水泥中某些成分相互作用生成含水硫酸盐结晶。
这些盐类在生成时体积膨胀。
经测定，当SO42-生成CaSO4·2H2O时，体积增大一倍；形成MgSO4·7H2O时，体积增大430％；体积增大使混凝土构筑物结构.4>酸性矿井水还是环境污染源。
采煤机相关英文文献翻译
英文原文：Control strategy for an intelligent shearer height adjusting systemFAN Qigao*, LI Wei, WANG Yuqiao, ZHOU Lijuan, YANG Xuefeng, YE Guo School of Mechanical & Electrical Engineering, China University of Mining & Technology, Xuzhou 221008, ChinaAbstract: An intelligent shearer height adjusting system is a key technology for mining at a man-less working face. A control strategy for a shearer height adjusting system based on a mathematical model of the height adjusting mechanism is proposed. It considers the non-linearity and time variations in the control process and uses Dynamic Fuzzy Neural Networks (D-FNN). The inverse characteristics of the system are studied. An adaptive on-line learning and error compensation mechanism guarantees system real-time performance and reliability. Parameters from a German Eickhoff SL500 shearer were used with Matlab/Simulink to simulate a height adjusting control system. Simulation shows that the trace error of a D-FNN controller is smaller than that of a PID controller. Also, the D-FNN control scheme has good generalization and tracking performance, which allow it to satisfy the needs of a shearer height adjusting system.Keywords: shearer; height adjusting system; dynamic fuzzy neural network1 IntroductionThe shearer and its control system are main components for coal mining. The shearing process includes drum lifting and traction control. Domestic shear drum lifting now uses manual adjustments after artificial observation or a geometric track cutting-memory method after trial manual adjustments from test cuttings. The installation of sensors on the shearer that could identify coal-rock has been proposed. Information from the sensors would be used to achieve drum height control directly by automatically lifting the shearer]1[. This technology, which is based on simple drum height feedback, has not been widely applied due to the structural complexity of the coal seam, technical problems related to identification ofthe coal-rock interface as well as roof, and floor, requirements for such comprehensive coal mining mechanization. Others have proposed an intelligent shearer height adjusting system based on a self-adaptive PID neural network control method]2[. This requires data samples from an operating shearer height adjusting system followed by careful choice of the neural network and adjustment of the algorithmic parameters. The suitability of the system would then be determined by checking performance against test samples. After the structure and parameters were determined the trained neural network could be applied to practical systems. The parameters could be ad-justed further while the system was running toachieve self-adaptive learning and control. Setting up such a system involves considerable uncertainty and a great deal of time.Considering the factors and the need for improving product quality and resource recovery by automatic control of the drum height we propose a new method called the shearer intelligent height adjusting system control method. It is based on Dynamic Fuzzy Neural Networks (D-FNN). D-FNN are neural networks that have the characteristics of powerful on-line learning, fast learning and good generalization. D-FNN give real-time control and improve dynamic characteristics of a shearer height adjusting system and provide a theoretical basis for designing an intelligent height adjusting control system for the shearer.2 Analysis of a shearer height adjusting system2.1 Structure of the shearer height adjusting systemThe shearer height adjusting mechanism uses a hydraulic servo system having good dynamic performance. Fig. 1 diagrams a drum shearer. The electro-hydraulic servo system controls extension of the hydraulic cylinder and moves the rocker arm to set the height. The adjusting mechanism is a planar open chain consisting of a series of connected rod structures and corresponding kinematic pairs. A descripion of the relative motion of the parts shows how height adjustment occurs. A detailed motion analysis follows. Suppose:1) All components are rigid and elastic deformation is ignored;2) Gaps between all mechanisms are ignored.2.2 Mathematical analysis of the shearer height adjustment systemFig. 2 shows the initial position of the hydraulic cylinder as A L , the end position as B L , the long arm of the rocker arm is L, short arm is R L , the draw bar between the height adjustment cylinder and the rocker arm is G L , the distance between the height adjustment cylinder and the rocker pivot is D and the angle between the long arm and the short arm is 0θ.Definition 1. Shearer mining height H:H=L θsin (1) End position B L is given by x L L A B ∆+= allowing the displacement of thehydraulic cylinder, x ∆, to be established.Definition 2. Displacement of the hydraulic cylinder, x ∆ , is:A B L L x -=∆ (2) whereWe write:(3)whereSubstitution gives x ∆ as:(4) Since b is given by θθβ-=` x ∆ can be expressed as a function of rocker-height to angle:(5) Kinetic analysis of the model shearer height adjusting system shows it is a third ordersystem. The system transfer function is [3]:(6) where K is the system gain, ζ is the system damping ratio, w is the natural frequency of the system, F (s) the Laplace transform of the servo mechanism, )(s x ∆ the Laplace transform of x ∆ (in Eq.(5)),x ∆ is derived from Eq.(6), the swing angle, θ , of the rocker arm is from Eq.(5) and θ controls the feedback.Since the height adjusting system is non-linear and a time-varying dynamic system a traditional PID controller cannot provide satisfactory control. D-FNN are proposed as meeting the requirements of reliability and real time performance.3 Dynamic fuzzy neural networksD-FNN are based on the expansion of Radial Basis Function (RBF) neural networks. The prominent characteristics of this learning algorithm are the simultaneous adjustment of parameters and the identification of an appropriate structure. This provides rapid learning suitable for real-time control and for modeling of the shearer height adjusting system ]64[- The structure of a dynamic fuzzy neural network is shown in Fig. 3.In Fig. 3 1x , 2x , …, r x are the system input variables, y is the system output, ij MF is the membership function, j, of the input variable, i, j R is the fuzzy rule of membership function j, j N is the normalized node of j, i ω is the connection weight of rule j and u is the whole system rule number.The swing angle, θ , of the rocker arm was chosen as the system input variable that controls expansion of the hydraulic cylinder. A Gaussian function, Eq.(7), is used for the membership function.(7)where i ranges from 1 to r, j ranges from 1 to u,ij u is the membership function, j, of i x , ij c is the center of the Gaussian membership function, j, of i x , j is the width of the Gaussian membership function, j, of i x , r is the input variable number and u is the number of the membership function as well as the whole system rule number.The output of j R , rule j, is obtained from:(8)where X is given by:and the center of RBF neuralnetwork j is given by:This gives the D-FNN model as:(9)where α is the connection weight of rule i.4 D-FNN control strategyThe D-FNN control scheme is shown in Fig. 4. The basic idea is obtaining the inverse characteristic of the shearer height adjusting system and then producing a compensation signal from this inverse dynamic model. There are two dynamic fuzzy neural networks here:A and B. Network A is for system weight training while networkB is a copy of the trained A network that is used for producing the control signal.The control algorithm is:(10) where x Δ is the expected displacement of the height adjusting hydraulic cylinder; PD Δx the actual displacement of the cylinder produced by the PD controller and DFNNB Δx the actual displacement of the cylinder produced by network B.The PD controller is for faster and more accurate tracking performance. The key to the D-FNN controlsystem is the training of D-FNN B to minimize the squared error between expected and actual displacements produced by network B]87[ :(11)A gradient descent method is used for the weight adjusting algorithm]9[:(12) where λ is the learning rate and λ >0. λ has a large influence on the convergence rate. Increasing of λcan speed up the convergence rate, which is more suitable for time-varying system modeling and control. At the same time the anti-interference performance of the system declines. A decrease in λ slows down convergence but produces a system less sensitive to interference. A self-adjusting learning rate method is proposed herein, the principle being that when the new error exceeds the last error overshooting has occurred and λ should be reduced. If the new error is smaller than the last error the weight adjustments are effective and λ should be increased. If the error is constant then λ is kept the same. This may be written as:(13) Tests show that D-FNN using the self-adjusting learning rate method requires much less training time than systems using a fixed learning rate.5 System simulationThe mathematical model and a D-FNN control algorithm may be used in a model shearer height ad-justing system built using Matlab/Simulink[]1510[-. The actual parameters are from a German Eickhoff SL500 machine. The shearer maximum cutting height is 5.50 m and the foot wall is 1.08 m. The angle of the rocker arm is –21.3°~+55°. The draw bar, LG , is 2.05 m, the short arm, LR, is 1.20 m, D is 0.9 m and the angle 670=θ5.1 Simulation of a D-FNN controllerSuppose the rocker arm moves within a range of –21.3°~+55°. The D-FNN control strategy traces the trajectory of the rocker arm and the trajectory tracing error are shown in Fig. 5. In Fig. 5b the maximum trajectory tracing error of the rocker arm is 0.65°, which occurs early in the training stage. At this point the D-FNN is undergoing on-line learning, namely learning the proper inverse model of the shearer height adjusting system. So in the early stage network B has insufficient accuracy to compensate for error in the control signals. But as training proceeds the average error drops until at the final stage it has been reduced to ±0.1°, which meets the system requirements.5.2 Simulation of a PID controllerThe trajectory of the rocker arm, and the corresponding tracing error, are shown in Fig. 6 for the traditional PID controller.As shown in Fig. 6b, the maximum trajectory error is 5.8°; this is unacceptable for the whole system. The simulation results show that the D-FNN controller is more robust and adjusts faster.6 Conclusions1) A mathematical analysis of the shearer height adjusting structure was used to build a mathematical model. The constraints between the control and feedback variables of the shearer height adjusting system were determined from the model.2) The combined advantages of fuzzy control and neural network control used in the D-FNN control strategy to adjust shearer height were described. A proposed control scheme of the system, having the desired inverse characteristic, is derived. By adjusting the weights and compensating for accuracy the control scheme satisfactorily met the needs of a height adjusting system.3) A simulated D-FNN controller system using parameters from an Eickhoff SL500 shearer was compared to a traditional PID controller: the D-FNN controller was more accurate. The D-FNN algorithm overcomes limitations of traditional network optimization algorithms andavoids falling into local minimum points. Self adaptive, on-line learning greatly improves the training speed. The system stability and accuracy meet the requirements for a shearer height adjusting systemAcknowledgementsFinancial support for this work, provided by the National High Technology Research and Development Program of China (No.2008AA062202), and China University of Mining & Technology Scaling Program, are gratefully acknowledged.References[1] Zhang J M, Fan X, Zhao X S. Automatic horizon control system of coal mining machine. Journal of China University of Mining & Technology, 2002, 31(4): 415-418. (In Chinese)[2] Liang Y W, Xiong S B. Neuarl network and PID hybrid adaptive control for horizontal control of shearer. In: Proceeding of the 7th International Conference on Control,Automation, Robotics and Vision IEEE. Singapore, 2002: 671-674. (In Chinese)[3] Lei Y Y, Yin Z X, Qian H. Study on hydraulic automatic ranging cutting height of shearer. Journal of Chongqing University, 1994, 17(1): 52-58. (In Chinese)[4] Er M J, Wu S Q. A fast learning algorithm for parsimonious fuzzy neural systems. Fuzzy Sets and Systems, 2002, 126(3): 337-351.[5] Gao Y, Er M J, Yang S. Adaptive fuzzy neural control of robot manipulators. IEEE Trans Ind Electron, 2001, 48: 1274-1278.[6] Chang Y C. Adaptive fuzzy-based tracking control for nonlinear SISO systems via VSS and H approaches. IEEE Trans Fuzzy Syst, 2001(9): 278-292.[7] Li C, Lee C Y. Self-organizing neuro-fuzzy system for control of unknown plants. IEEE Transactions on Fuzzy Systems, 2003, 11(1): 135-150.[8] Er M J, Low C B, Nah K H, Lim M H, Ng S Y. Real-time implementation of a dynamic fuzzy neural networks controller for SCARA. Microprocessors and Microsystems, 2002, 26(9/10): 449-461.[9] Juang C F, Lin C T. Noisy speech processing by recurrently adaptive fuzzy filters. IEEETransactions on Fuzzy Systems, 2001, 9(1): 139-152.[10] Esposito A, Marinaro M, Oricchio D, Scarpetta S. Approximation of continuous and discontinuous mappings by a growing neural RBF-based algorithm. Neural Networks, 2000, 13(6): 651-665.[11] Magee D P. Matlab extensions for the development, testing and verification of real-time DSP software. In: Proceedings of 42nd Annual Conf Design Automation. California, 2005: 603-606.[12] Bhatt T M, McCain D. Matlab as a development environment for FPGA design. In: Proceedings of 42nd Annual Conf Design Automation. California, 2005: 607-610.[13] Yang Y J, Deng H Y, Li X. Simulation of screening process based on MATLAB/Simulink. Journal of China University of Mining & Technology, 2006, 16(3): 330- 332.[14] Liu S Y, Du C L, Cui X X, Cheng X. Model test of the cutting properties of a shearer drum. Mining Science and Technology, 2009, 19(1): 74-78.[15] Fang X Q, Zhao J J, Hu Y. Tests and error analysis of a self-positioning shearer operating at a manless working face. Mining Science and Technology, 2010, 20(1): 53- 58.中文翻译：采煤机高度智能调节系统控制方案范启高，周丽娟，李伟，王玉桥，杨学锋，叶国安机电工程学院，中国矿业大学，徐州221008，中国摘要：一种采煤机高度智能调节系统是在无人工作面开采的关键技术。
采矿工程中英文对照外文翻译文献
中英文资料外文翻译Optimization of soft rock engineering with particular reference to coalminingAbstractSoft rock engineering is a difficult topic which has received much attention in the field of rock mechanics and engineering. Research and practical work have been carried out, but much of the work has been limited to solving problems from the surface. For overcoming the difficulties of large deformations, long durationtime-dependent effects, and difficulties in stabilizing the soft rock, the problem should be tackled more radically, leading to a more effective method of achieving optimization of the engineering system in soft rock. A summary of the optimization procedure is made based on engineering practice.1. IntroductionThere are many soft rock engineering problems around the world, involving engineering for mines, highways, railways, bridges, tunnels, civil subways, buildings, etc. Engineering losses have occurred because of volumetric expansion, loss of stability of the soft rock, etc. This has been an important question to which much attention has been paid in engineering circles, and in the field of academic rock mechanics. Since the 1970s, considerable research and practical efforts have been made in the field of soft rock engineering in various countries, but the major efforts were concentrated on such aspects as the method of construction, the design and reinforcing of the supporting structures, measurement and analysis of the rock’s physical and mechanical properties, its constitutive relations and engineering measurement.It has been found that the soft rock engineering problem involves complex systematic engineering including such subsystems as classification of soft rocks, judgement concerning the properties of soft rock, project design and construction. Only by considering the integral optimization of the system can we obtain animproved solution to the problem. Hopefully, a radical approach can lead to engineering feasibility, lower costs and engineering stability in order to achieve the engineering objectives.1.1. Mechanical properties of soft rock and associated engineeringSoft rock is an uneven and discontinuous medium. Its strength is low, with a uniaxial compressive strength usually lower than 30 MPa. Some soft rocks expand when they are wet. Cracks in some soft rocks will propagate easily — which makes them exhibit volumetric expansion. Large deformation and creep can occur in soft rocks. Many soft rocks are compound ones which have composite properties formed from two or more sets of constituent properties. Soft rock can be graded into divisions according to its properties. After engineering has occurred, soft rock can deform rapidly and by time-dependent deformation, owing to its low strength and sensitivity to the stress field. With the effect of water, the expansive minerals in soft rocks volumetrically expand, which causes large convergent deformations, which leads to damage of the surrounding rock.The mechanical properties of soft rocks appear so various and different that it is difficult to express them with mathematical formula, which is the technological challenge for soft rock engineering.1.2. Engineering in soft rock and its optimizationBecause soft rock engineering can induce large deformations, the maintenance of the engineering can be difficult. Moreover, volumetric expansion and loss of stabilization of the surrounding rock often causes damage to supporting structures. If we use strong supports to control the deformation of the surrounding rock, the engineering cost will be high, and the construction time will be increased by repeated installation of support, sometimes the support itself has to be repaired. In order to obtain the benefits of easier construction and lower cost, the integral optimization of the system must be carried out and managed in a systematic and comprehensive way.Design and construction are the two important steps in soft rock engineering. These must begin by understanding the physical and mechanical properties of soft rock, in the context of the stress field, hydrogeology and engineering geology. The engineering design plan is conceived as a whole according to the theory of rock mechanics and combining practical data from adjacent or similar projects, including integrating the many factors. The establishment of the correct soft rock engineeringsystem should come from practice, basing on a full mastery of the factors. The scheme is shown in Fig. 1.Fig. 1. Engineering system for soft rock.Optimization of soft rock engineering is achieved by making the surrounding rock interface with the supporting structure such that the engineering will be stable. The key technological strategy is to avoid a high stress field and enhance the supporting ability of the surrounding rock. Feasible measures are as follows: reducing the external load; optimizing the engineering structure’s size and shape, improving planar and cubic layouts of engineering; choosing better strata, and structure orientation, etc., as shown in Fig. 2.Fig. 2. The principle of the optimization process.According to these ideas, take the development of a coal mine in soft rock as an example. Integrated optimization of the development system of the mine should take the relevant factors into account: existing information; an overall arrangement foroptimal development and production; eliminate adverse factors; and deal with the problems of soft rock by a simple construction method. The content of the first part of the optimization includes: choosing the mine development method; deciding on the mining level; and determining layers in which the main roadways are to be located. Also important is arranging a reasonable layout of the pit bottom and chamber groups and seeking to reduce the deviator stress caused by mutual interference of the openings. Openings perpendicular to the direction of horizontal principal stress should be avoided when choosing the driving direction of roadways. Optimizing the layout of the mining roadways reduces the damage to support caused by moving loads introduced by mining. Further optimization is related to the geometry and size of the roadway sections, the supporting structure, and the method and technology of construction. Finally, by measuring and monitoring during construction, feedback information can be obtained to ensure that the engineering is running on the expected track and, if there is any deviation, corrective action can be implemented. The system is shown in Fig. 3.Fig. 3. Systematic optimization of coal mining in soft rock.2. Engineering examples2.1. Mine No. 5 in Youjiang coal mine, ChinaThe mine is situated to the east of Baise Coalfield, in the West of Guangxi Zhuang Autonomous Region. It belongs to the new third Period. The mine area is located at the edge of the south synclinal basin. There are three coal layers; the average thickness of each seam is 1–2 m; above and below the coal layers are mudstone, whose colours are grey, greyish white, and green. There are minerals of mixed illite and montmorillonite in the rock, montmorillonite 5–8%, and illite 7–20%. The rock’suniaxial compressive strength is 4–5 MPa, the average being 4.8 MPa. There are irregular joints in the rock, but distributed irregularly, and the rock’s integral coefficient index is 0.55. Most of the cracks are discontinuous, without filling matter in them. The surrounding rock is a soft rock subject to swelling, with low strength, and is quite broken. The strike of the coalfield is NEE, the dip angle of the coal layers is 10–15°. The mine area is 6 km long along the strike, and 1 km long along its inclination, its area is 6 km2, the recoverable reserves are 4,430,000 tons. In the adjacent mine No. 4, the maximum principal stress is NNE–SSW, approximately along the seams’ inclined direction. A roadway perpendicular to this direction has convergence values of 70–100 mm, the damage of roadway supports is 51%. A roadway parallel to the direction of maximum principal stress has convergence values of 20–40 mm, the damage rate of supports is 12%, and the average damage rate of the mine is 40%.In the design of the mine, a pair of inclined shafts were included. The level of the shaft-top is +110 m, the elevation of the main mining level is located at −120 m. Strike longwall mining is planned, arranging with uphill and downhill stope areas, as shown in Fig. 4.Fig. 4. Development plans for Mine No. 5 in Youjiang.The first optimization measure is to weaken the strain effect of the surrounding rock in the mine roadway caused by the stress field. Roadways are arranged as far as possible to be parallel with the maximum principal stress (that is, approximately along the inclined direction) so as to reduce the angle between them. The strike longwall mining is changed into inclined longwall mining, the mine is mined upward by using the downhill stope area, the main mining level is elevated by 20 m, 1131 mof roadways are saved and the cost of the roadway construction and facilities is saved ¥2,760,000 ($336,600). The new system is shown in Fig. 5.Fig. 5. Development system plans after optimization for Mine No.5 in Youjiang.The second optimization measure is to change the layout of the pit bottom and openings to be parallel with the maximum principal stress as far as possible. The total length of roadways initially designed was 1481 m, and 30.11% of them were arranged to be perpendicular to the maximum principal stress. After amendment, the total length of roadways is 1191 m, which is a decrease of 290 m, and with only 24.69% of roadways that are perpendicular to the principal horizontal stress, roadways are easier to maintain. As shown in Fig. 6 and Fig. 7.Fig. 6. Layout of the pit bottom and chamber initially designed forMine No. 5 in Youjiang.Fig. 7. Layout of the pit bottom and chamber after the optimizationfor Mine No. 5 in Youjiang.The third optimization measure is to excavate the section of the roadway in a circular arch shape to reduce the stress concentrations. In order to increase the supporting ability of the surrounding rock itself, after the roadway has been excavated, rockbolts are installed as the first support. Considering the expansivity of the surrounding rock, guniting is not suitable. The secondary support is the use of precast concrete blocks. Between the support and the surrounding rock, the gaps should be filled with a pliable layer of mixed lime-powder with sand. This produces the effect of distributing the stress and has a cushioning effect when the soft rock is deforming; also, it inhibits the soft rock from absorbing water and expanding. This scheme is shown in Fig. 8Fig. 8. Optimization design for the supporting structure of the mainroadway for Mine No. 5 in Youjiang.The fourth optimization measure is to simplify the chamber layout so as to reduce the number of roadways. For example, in order to decrease the stress concentrations by the roadway, the number of passageways in the pumproom and the sub-station can be reduced from three to one, and the roadway intersections connecting atright-angles can be reduced from 14 to nine.The fifth optimization measure is in accordance with the different stratigraphical lithologies which the roadways pass through, and for harder rock regions to change the roadway section into a structure with straight-sided semicircular top arch and arc bottom arch, and another structure with a straight-sided horse-shoe arch, so that the investment of supporting structure can be saved when there are better rock masses with comparatively few fractures.In construction, waterproofing and draining off the water should be implemented, and the catchment in the roadway bottom should be strictly prevented because it may cause the bottom rock to expand. When the opening groups are excavated, the construction sequence must be considered, enough rock pillar must be reserved, and the construction method of ‘short-digging and short-building’ must not be used, so that the interactions can be avoided.By the optimization described above, after the roadways have been constructed, the serviceable roadway is 95.5% of the total, 55.5% more than that of the adjacent mine No. 4. The length of the roadway was reduced, and ¥3,700,000 ($450,000) saved. In addition, ¥3,000,000 ($360,000) was saved in the maintenance costs of the roadways before the mine was put into production, so, the cost saving totals¥6,700,000 ($810,000) in all. After the mine has been turned over to production, the main designed capacity was reached in that year, and added to the saved money for the maintenance cost of roadways in production, there was ¥8,700,000 ($1,050,000) saved.2.2. The coal mine at Renziping, ChinaThe mine lies to the south of Qinzhou coalfield in Guangxi Zhuang Autonomous Region. It belongs to the new third Period and synclinal coal basin tectonics. There are two coal layers in it, the main seam thickness is 12–15 m. The roof and floor of the coal layers are arenaceous–argillaceous rocks, whose colour is greyish white, and whose essential minerals are quartz and kaolinite. The uniaxial compressive strength of the rock is from 10 to 15 MPa. Rock masses are quite integral with fractures only in it occasionally. It belongs to the class of soft rock that has weak expansion, lower strength, and is quite broken. There are faults around the coalfield basin which are8 km long and 1.5 km or so wide. Slopes are inconsistent, the edge angles are 25–40°, and the bottom of the coalfield is gentle. Affected by tectonic stress in the NW–SE direction, there is an inverse fault in the south. After the mine had been developed and put into production, a main roadway at the 250 m level was excavated along the strike, and the mine was mined by the ‘uphill and downhill stope area’. Affected by the rock stress, many parts of the main roadway have ruptured, parts have been pressed out, and supports have been broken; the serviceable rate of roadway supports was less than 40%, which seriously affected the haulage and ventilation of the mine road. In the following 10 years of production, the rated production output was not achieved and losses occurred leading to economic disbenefit.Through on-the-spot observations, it is apparent that the coalfield is affected by the tectonic stress field, that the deformation in the soft rock is serious, and is larger than that caused only by the vertical stress component. The technological reformation measures for the mine are proposed as follows.The first measure is to extend the depth of the shaft and abandon the main roadway excavated along the strike, and transform it into a bottom panel stonedoor along the synclinal basin minor axis to make it parallel with the main principal horizontal stress. The mining face can be laid on top of it. The force endured by the stonedoor is quite small, and the stonedoor is easy to maintain, as shown in Fig. 9.Fig. 9. Contrasting layouts before and after optimization at the coalmine in Renziping.The second measure is to select an improved stratum to lay out the stonedoor. If it is placed in the grey arenaceous–argillaceous rock, its uniaxial compressive strength is 15 MPa and is easy to maintain, constructing in the normal excavation manner, and supported with a granite block building body.After the mine was constructed, the maintenance of the stonedoor was in a better state, the serviceability rate of the roadway was raised to 85%, which is 45% more than that before the optimization. The haulage and ventilation of the mine were also improved, to enhance the normal production. The coal production of the mine has surpassed the designed capacity, the loss has been reversed and the mine has been transformed to a profitable enterprise.3. ConclusionsSoft rock engineering for coal mining involves many complex factors. Unable to solve the problems completely by quantitative means, much of the engineering relies on feedback after observation on the spot. The technique described in the paper — of systematic decomposition of the system into the component elements, individual optimization and then synthesis into overall optimization — has achieved good results in practice, as illustrated by the three coal mine examples.In fact, the basis of the technique is the process of applying basic rock mechanics principles, such as orienting roadway tunnels to be parallel to the maximum horizontal principal stress and avoiding complex excavation shapes. This involves major changes to coal mine layouts and thus represents a strategy of taking radical measures to solve soft rock engineering problems. If such radical measures are taken together with holding stopgap measures, the soft rock engineering can be optimized.煤矿开采中的软岩优化工程摘要软岩工程是一个已引起广泛关注的岩石力学与工程领域中的困难课题。
采煤机毕业设计外文翻译
英文原文THE SHEARERShearerLongwall equipment consists of three major components: the hydraulically powered roof support, the chain conveyor, and the coal-cutting machine.The two different types of coal-cutting equipment used in coal mines are shearers and plows.Plows are used in low seams, 42in. or less. The unit consists of steel construction equipped with carbon-tipped bits. This passive steel unit is engaged to a guiding system on the face conveyor. An endless round link chain powered by synchronized electric drives on each end of the face conveyor pulls the plow body at speeds between 120 and 420 ft/min along the face.For the cutting process the plow has to be forced against the coal face. This is done by hydraulic cylinder attached to the gob side of the face conveyor and to the base of the supports, or by a separate hydraulic prop. Forces of between 1and 3 tons are applied per cylinder.A plow drive is attached to each drive frame of the face conveyor. Only 30% to 60% of the drive power supplied to the plow is used for cutting and loading of coal; the remainder is lost in friction. This means that the power loss is considerably higher than that of a shearer, which uses 75% to 85% of its power for the removal of the coal. As a result, rather large drives are required at the face ends.Although there are many models, the shearer has several common basic components. A double-ended ranging-drum shearer (Fig. 8. 1), for example, consists of four major components: electric motors, gearheads, haulage unit (power pack), and cutting drums.The electric motor ranging from 300 to 1000 horsepower (223~750kW) is the power source for the shearer. It provides power to run the hydraulic pumps in the haulage unit and the gearheads for the cutting drum. The large-capacity shearers are generally equipped with two electric motors: one for the haulage unit and one gearhead and the other for the other gearhead and other ancillary equipment. Themotors can be remotely controlled.There are two gearheads, one on the left-hand the other on the right-hand side of the shearer. Each gearherad consists of a gearhead gearbox and a ranging arm.The cutting drum is laced with spiral vanes on with spiral vanes on which the cutting bits are mounted. Its diameter ranges from 34 to 72 in. (0.86~1.83 m) with rotational speeds from 30 to 105 rpm. The trends are toward fewer but larger bits and slower drum speed for better cutting efficiency and less coal dust production. The drums are also equipped with power cowls to increase the coal loading efficiency. The power cowl is usually located behind the cutting drum. For that reason, it can be rotated a full 180º.The electric motor, haulage unit, and gearhead boxes combine to form the shearer’s body which is mounted on the underframe. The underframe has four sliding shoes. The face-side shoes are fitted and ride on the face-side top guide of the face conveyor pan, and the other two gob-side sliding shoes are fitted on a guide tube to prevent derailment. The tramming aped of the shearer ranges from 19 to 46 ft/min (5.8~14.0 m/min).In addition, the shearer is equipped with auxiliary hydraulic pumps and control valves for operating the ranging arms and power cowls, water spraying devices, cable, chain anchorage and tensioners, and so onIn selecting the shearer, mining height should first be considered; that is, the diameter of the cutting drum, body height, length of the ranging arm, and swing angle must be properly selected. For the double-ended ranging-drum shearer, the maximum mining height cannot exceed twice the diameter of the cutting drum. The mining height can be determined by (Fig.8.3)H=Hb-B/2+Lsinα+D/2Where H=seam thickness or mining heightHb=shearer’s body heightB=body depthL=length of the ranging armα=the angle between the ranging arm and the horizontal line when the ranging arm is raised to its maximum heightD=diameter of the cutting drumFor example, for the Eichhoff EDW-170 L double ranging-drum shearer, Hb=4.3 ft, L=3.90 ft, α=52°，and D=5.3 ft. Its maximum cutting height is H=9.2 ft..Types of modern shearersSince its first appearance in 1954,the shearer has undergone continuous changes both in capability and structure. It is now the major cutting machine in longwall coal faces. There are two types of shearers, single-and double-drum. In the earlier models, the drum in the single-drum shearer is mounted on the shearer’s body and cannot be adjusted for height. Therefore it is not suitable for areas where there are constant changes in seam thickness and floor undulation. Thus the single-ended fixed-drum shearer is used mostly for thin seams.Figure 6.10 shows a single-drum shearer with a ranging arm. The cutting drum is mounted at the very end of the ranging arm. The ranging arm can be raised up and down by hydraulic control to accommodate the changing seam thickness and floor undulation. But when the seam exceeds a certain thickness, the single-drum shearer cannot cut the entire seam height in one cut and a return cutting trip is necessary to complete a full web cut. Furthermore, since the drum is located on the headentry side, it generally requires a niche in the tailentry side. A niche is a precut face end, one web deep and a shearer’s length long. With a niche at the face end the shearer can turn around.Nowadays, the double ranging-drum shearers are used predominantly. The shearer cuts the whole seam height in one trip. The two drums can be positioned to any required height (within the designed range) during cutting and lowered well below the floor level. The arrangement of the drums enables the whole seam to be cut in either direction of travel, thereby ensuring rapid face advance and shortening roof exposure time. There are various types of double ranging-drum shearers. Based on the location of the drums, there are two types: one with one drum mounted on each side of the shearer’s body and the other with both drums mounted on one side of the machine. The former type is the most widely used. Its advantage is that with one drum on each side of the shearer, it can sump in either direction. During the cutting trip, the leading drum cuts the upper 70% of the seam height while the rear drum cuts thelower 30% and cleans up the broken coal on the floor. The two drums are approximately 23~33 ft (7~10m) apart. When the shearer is traveling in the opposite direction to that of the face conveyor, the coal cut by the leading drum has to pass under the shearer’s body, which increases the moving resistance of the shearer and the face conveyor and could cause a “crowding” condition. If the broken coal is too large, it may block the shearer and stop the operation. In general, when the shearer and the face conveyor are traveling in the opposite directions, approximately 70% of the coal taken by the leading drum will pass under the shearer. But when they are traveling in the same direction, the coal taken down by the rear drum together with the float coal from the floor constitute the approximately 30% of the coal that has to pass under the shearer. The former case consumes 25% more power than the latter. As compared to the single-ended shearer, the underframe of the double-ended shearer is higher, thereby ensuring a sufficient cross section for coal passage.Based on the method of adjusting the height of the cutting drum, there are also two types of shearers: ranging-arm shearer and gearhead shearer. The former one is commonly used, whereas the latter one is a recent development. The advantage of the gearhead shearer is that the haulage unit is located at the center of the shearer’s body and mounted on the underframe. On both sides of the haulage unit, there is a gearhead. Each gearhead contains an electric motor and a speed-reduction unit. The gearhead is raised and lowered by an adjustable hydraulic ram. The adjustable range of cutting height is large. It can reach up to 4.6 ft(1.4m).Based on the mounting relation between the shearer and the face conveyor, there are also two types: the regular type which rides on the conveyor and the in-web shearer which moves on the floor in front of the conveyor. The in-web shearer is used mainly for the thin seams. As it moves along the face, the leading drum cuts the coal, making a sufficient space for the passage of the passage of the shearer’s body. Haulage of the shearerThere are two types of shearer haulage: chain and chainless. These are discussed separately in the following paragraphs.(1)Chain haulageThe haulage chain is a round-link chain which extends along the whole face width and is fixed on both ends at the head and tail drives of the face chain conveyor, respectively. The chain also passes through the driving and deflecting (or guiding) sprockets in the haulage unit of the shearer. As the driving sprocket rotates, its teeth trap to the matching chain links and move along the nonmoving haulage chain, thereby pulling the shearer along. When the driving sprocket rotates counterclockwise, the shearer moves to the right. Conversely, when the sprocket rotates clockwise, the shearer moves to the left. That part of the chain in front of the moving shearer isgenerally tight or on the tensioned side whereas the other side, behind the moving shearer, is slack or on the slack side.The total resistance encountered by a cutting shearer consists mainly of the cutting resistance of the drum, coal loading resistance, and the frictional resistance between the conveyor and the shearer. The summation of the three types of resistance is the total haulage resistance of the shearer. The haulage unit must provide sufficient haulage power to overcome the total haulage resistance so that the shearer can move along smoothly. In Fig. 6.15 the tensile force in the tensioned side is P2 and that in the slack side is P1. Since the haulage force(P2) is the summation of P1 and P, if the chain on the slack side is completely slack, P1=0, then the tensile force in the tensioned side will be the required haulage force, P2=P. Under such conditions, although the chain is subjected to relatively small tension, the driving sprocket can not pass out the chain smoothly and may easily cause chain “stuck” or sudden tensioning of the chain. Thus in actual operation, the slack side normally maintains a small tension, i. e. , P2=P1+P. Only when the tensile force in the tensioned side is sufficient to overcome the total haulage resistance and the tensile force in the slack side, the shearer will be able to move.When the shearer starts cutting from one end of the coal face, the haulage chain is relatively slack. As the shearer moves along, the chain is gradually tightened. When the shearer is near the other end of the coal face, the tensile force in the haulage chain is greatest. At this time the chain is most easily broken. In order that the tensile force on the tensioned side is not too high and that there is a sufficient tensile force on the slack side, most shearers are equipped with tension takeup systems. The tension takeup system is mounted at one end or both ends of the face conveyor depending on whether unidirectional or bidirectional cutting is employed. The haulage chain is connected to the tension takeup system. There are many types of tension takeup systems. But the basic principles are about the same.The problems associated with chain haulage are chain sticking, chain breakage, and chain link tangling. They are due mainly to the fact that the haulage chain is lengthened and becomes loose after some periods of usage.(2)Chainless haulageIn response to all the disadvantages associated with the chain haulage, the chainless haulage was developed. According to the haulage principles, the chainless haulage can be divided into three types: drive chain-rackatrack, drive wheel-rackatrack, and ram propulsion. The wheel-rackatrack haulage is the most popular type.Figure 6.16 is a double-ended ranging-drum shearer equipped with the wheel-rackatracd haulage system. The haulage driving unit is similar to theconventional ones. The driving sprocket matches an idler sprocket, which in turn rides on the rail track made of steel peg rods. Thus, the driving system of power transmission is highly efficient. The rack is made of sections that have the same length as the conveyor pan, but they are installed in such a way that the center of each section is directly above the connection line between two adjacent pans. This will ensure maximum vertical and horizontal flexibility of the pans and keep the pitch deviation in the gap between two rack sections within admissible limits. Two methods are used to connect the line pans with the rack sections: one is to tie the rack sections to the sides of the line pans with screws and the other is to set the rack section on the sliding channel. Only the rack sections on both ends of the conveyor are fixed, so that a limited amount of flexibility in the conveyor direction is permitted. In Fig. 6.17 (b), the hook shape anchor on the rack section locks and slides on the guide tube of the line pans. This method is good for converting chain haulage to chainless haulage.Figure 6.18 is another model of the wheel-rackatrack chainless haulage system. The driving sprocket is engaged directly to a special sprocket called Rollrack which has five hardened steel rollers spaced equally around the circumference. As the special sprocket or Rollrack rotates, the steel rollers engage on the teeth track of the rack and pull the shearer. Thus it is also called Roller-Teeth Rack chainless haulage.中文译文采煤机滚筒式采煤机长壁工作面的设备包含三个主要部分：液压支架，刮板运输机和破碎机。
薄煤层综采设备的研制及工艺参数优化外文文献翻译、中英文翻译、外文翻译
【外文文献】1The thin coal bed synthesis picks the equipmentthe development and the craft parameter optimizationMainly discussed the thin coal bed synthesis which Zaozhuang Mining industry Group Company independently developed to pick the equipment in Tian the Chen Kuang success application, and to its supplementary equipment technological transformations and the technical characteristic, the working surface geological condition, the synthesis picked the equipment the craft parameter optimization and the working surface working procedure reasonable match safeguard technology measure has carried on the thorough analysis and the introduction.Because the thin coal bed its mining space is narrow, the efficiency is low, the working surface condition is bad, machinery equipment not necessary or mining coal craft imperfect and so on technical questions, difficulty with realizes the mine pit highly effective and the safety in production.Zaozhuang Mining industry Group Company profits from the experience which my guozhong thick above coal bed synthesis picks, picked the supplementary equipment in the thin coal bed synthesis the development and the craft parameter optimization aspect has carried on the beneficial exploration.In October, 2003, ore 531 working surfaces equipped in its Tian the Chen has independently developed and the improvement three machines supplementary equipment, has obtained the tangible effect, realization maximum daily production 3504t, the average month produced 89636t, created the roller thin coal bed synthesis to pick the unit to yearly produce 1,000,000 ton new levels.Equips this working surfaceequipment fund investment is 1088.10 Yuan, the equipment does not invest into the equipment coal plow surface 1/10.First, the synthesis picks the three machines necessary and the technical characteristic(1) hydraulic pressure supportAccording to the thin coal bed mining characteristic, uses the computer to carry on the movement analysis optimization and the intensity design to the support four link motion gears, satisfies the working condition, optimized the support structure:(1) support for the support shield type, has used the overall top-beam, two column supports has satisfied the big expansion and contraction request;(2) main structural element with the Q550 high strength structure steel plate manufacture, reduced the support weight.Front uses welds preheating, after welds the artificial aging welding craft, the guarantee structural element welding quality;(3) selects the great current capacity hydraulic pressure part, enhances the support the speed of response;(4) reasonable arrangement hydraulic circuit system, has enlarged the human, machine the space.Its development ZY2400/08/19 hydraulic pressure support technical characteristic is as follows: Two column support shield type, support 0.8~1.9m, support width 1.43~1.6m, center distance 1.5m, working resistance 2400kN, supports and protections intensity 0.41~0.46MPa, the adaptation inclination angle is not bigger than highly 35°, opera ting mode for neighbour control, support weight 6500kg.(2) coal mining machineUnifies thin coal bed mining the technical characteristic, has carried on the transformation to the coal mining machine following several aspects:(1) improvement design pump box, the solution gives off heat the question, satisfies the synthesis to pick the operation percentage high operating mode need;(2) designs a group of tapering spindle rocking shaft specially, causes the drum circle diameter to reduce, increases the leaf blade altitude correspondingly, does an inside job the quantity request satisfiedly;(3) optimized drum design, increases the leaf blade spiral angle of climbing reasonably, the improvement coaling effect;(4) decreases the fuselage suitably highly (824mm), coal mining machine each big joint place has made the corresponding improvement.After the transformation coal mining machine MG200-BW2 technical characteristic is as follows: Picks high scope 1.0~2.0m, the adaptation inclination angle is not big ger than 35°, the adaptation coefficient of hardness f≤3.5, drum diameter 800/1000mm, machine surface altitude 824mm, does an inside job measures 91mm, the hauling way for the non-chain hauling, biggest force of traction 250kN, hauling speed 0~6.14m/min, installing equipment power 200kW, voltage rank 660/1140V, machine gross weight 15t, machine total length 7858mm.(3) scraper conveyerMainly has carried on the transformation to the scraper conveyer in following several aspects:(1) has used in the thin coal bed scraper conveyer the double strand transmission structure, loses the coal condition to be able to improve;(2) home for the first time used middle the 22E trough section on the thin coal bed scraper conveyer, the complete machine rigidity, the intensity had enhances greatly;(3) reduces the nose, the airplane tail trough highly (is excessively 430mm), improved the coal mining machine to the nose, the airplane tail coal wall cutting condition;(4) strengthened the shovel board, the cable tank frame, the hauling platoon has sold and so on place the joint structure.After the transformation scraper conveyer SGZ-630/220 technical characteristic is as follows: Completed length 170m, the transportation measures 450t/h, the installing equipment power 2×110kW, scraper chain fast 1.07m/s, tight chain way for brake disc tight chain.Second, working surface geological conditionThe development synthesis picks the equipment ore 531 working surfaces to apply for the first time in Tian the Chen, the working surface moves towards the long wall type arrangement, moves towards the length is 950m, the inclined length is 156m, coal bed thickness 0.4~3.0m, average 1.25m, coefficient of hardness f =2, the coal bed inclination angle 10°~15°, average 13°, reserves 283,400 t.Coal dust explosion index 31. 9%, is the strong explosive coal bed.The working surface has the mudstone false roof partially, thick 0~1.8m, soft easy to brave, its upside divides into the iron grey thin silicarenite, about its lower part lamination thick 1.5m for goes against directly, above for average thickness 33.5m, hard, the crevasse growth always goes against.The ledger wall partially has 0.1~0.4m charcoal mudstone, the direct bottom is the pessimistic siltstone, thick 2.6m, the ins and outs are the pessimistic novaculite, hard, the bedding is clear, thickness 16m.North 531 working surfaces are located five pick lower part the area, the track descends a mountain the left wing, ground table +45m, mine shaftelevation - 722m~-768m, the geological condition is complex, tunneling period exposition fault 8, above in which 1.0m fault 4, the F6 reversed fault dropping variance is 4.0m, also has strip width 20m, extends the 220m wash zone along the trend to pass through the entire working surface.Third, working surface craft parameter optimizationThe working surface reasonable craft parameter determination, is the synthesis picks the supplementary equipment to realize the working surface high production foundation.(1) section of deep choiceThe overall evaluation coal mining machine power, the anthrax coefficient of hardness, coal bed thickness and pick high, the roof jointing growth situation, the support press forcing crisp coal factor definite truncation depth and so on wall depth, support supports and protections way.Through analyzes the working surface geological condition and the equipment necessary situation earnestly, the definite truncation depth is 0.6m.When roof jointing growth, cave-in of sides of a mine tunnel serious, each knife tries to break up a fight when carries on supports and protects in advance, enhances the circulation per unit area yield.(2) coal mining machine hauling speed V determination (formula omitted)(3) supports and protections with moves a wayUses a neighbour operation, prompt supports and protections.In the mining coal machine cut from now on, first will move the support to support the roof, then will again move the conveyer.The union coal bed thickness grasping lengthening bar expands and contracts the scope, in order to and supports and protects the roof highly by the reasonable frame position.When roof situation permission, moves in turn and separates the frame to move to unify, guaranteed moves a speed to satisfy the coal miningmachine coal cutting speed, realizes continuously the fast coal cutting need.(4) coal mining machine feed wayUses the MG200-BW2 coal mining machine to fall the coal, unidirectional mining coal, middle bevelling feed.The first drum shears goes against the coal, the latter drum shears the bottom coal, from notching.Fourth, working surface working procedure match safeguard measure The thin coal bed synthesis picks the working surface reasonable craft parameter the effective safeguard, mainly includes the working surface each transportation link the intercoordination and the over-load protection, the long distance communication direction, the working surface “three straight one even” and the geologic structure control measure, coal mine has used the home most advanced TK-200 communication control system for this Tian the Chen, strengthened the working surface production management, had guaranteed the working surface various working procedures best match, reduced the working surface failure rate large scale, enables the working surface operation percentage to achieve above 90%.(1) TK-200 communication control system application(1) system compositionThe TK-200 communication control system by the TK110 working surface controller, the TK120 power source, the TJ100 mineral product electric current detector set, the TK130 micro telephone, the TK130C multi-purpose telephones, the TK150 intelligent terminal, the TK150E intelligence coupler and the TK130-X five core belt shield mineral product pulling force electric cable is composed.(2) system application effectThe TK-200 communication control system application, fully displays its communication control integration function, reduced the working surface equipment breakdown large scale, maximum limit has realized during various working procedures coordinated operation, raised a working surface man-hour of use factor enormously, had guaranteed powerfully the thin coal bed working surface high production is highly effective.Its application effect mainly manifests in:First, because the TK-200 communication control system has arranged 12 TK130 system telephone in the working surface, is equipped with the control bench on the electric train, between working surface all telephones and the control bench may converse on the telephone willfully, the control bench may realize the working surface all equipment common control, reduced the mechanical and electrical failure rate large scale.Second, because the working surface micro telephone can realize the working surface on all fronts to amplify along the route, therefore enormous place then personal servant party chief, the Leader Ban production control, changed the former personnel back and forth to move the direction, rocks the sending a letter number, the frontline propaganda relation way, strengthened between the working surface each production working procedure coordination and the unification, causes between various working procedures the close coordination, displays in fully the unit time the regular cycle operation validity, enhanced the working efficiency greatly.Third, because has used the common control and the working surface along the route block system, enables the working surface along the route operator only the engine off, cannot starting.If must starting, informs the control bench starting, the control bench when, must carry on the language to report to the police, and is equipped with the delay feature, avoided formerly being blind opens the vehicle to damage theelectromechanical device or to create the security accident the phenomenon.If the working surface has the breakdown along the route, the operator may the rapid block system engine off, and informs all operating personnel, like this eliminates the accident in the embryonic stage, thus has guaranteed the safety in production.Fourth, TK-200 communication control system itself has provided the TJ100 electric current examination alarm device, can as necessary uninterrupted carry on the examination to the working surface electric current, once examines the operating current to surpass the setting value, then carries on reports to the police, then the operator may adjust the coal cutting speed and the reduced mining coal quantity promptly, avoided because of the pressure which overloaded creates reduction gear the accident phenomenon and so on sliding, burning the electrical machinery, damages occurrences, not only like this has facilitated the production, enhanced the efficiency, moreover reduced the material and the fitting consumption greatly.Fifth, Tian the Chen ore 531 working surface transportation lane arranges 3 belt conveyers and the slanting lane 1 scraper conveyer, transports the link to restrict the working surface operation percentage directly.After uses this system, through carefully calculates the most appropriate slanting lane scraper conveyer and the belt conveyer load, carried on to the working surface scraper conveyer operating current has reported to the police the hypothesis, thus reduced the slanting lane scraper conveyer and the belt conveyer overload and the time of idle running, not only saved the electrical energy, moreover enhanced the working surface operation percentage.(2) working surface geological condition compatibility control measureGuarantees the working surface “straight three one even” is realizes the thin coal bed synthesis to pick the working surface regular production the effective method, when especially geologic structures and so on working surface fault or fold, the working surface equipment adapts the geological condition with difficulty, must strengthen the working surface production management, takes the effective control measure, reduces the equipment failure rate, enhances the working surface operation percentage.(1) guarantees the working surface “straight three one even” measure.The working surface implements the back guy management; The working surface hand illumination lamps and lanterns make the frame of reference; Pushes when slides, guarantees goes against slides the hoisting jack the traveling schedule to meet the standard requirements; If the working surface appears partially time not the straight phenomenon, should move promptly or moves slides; Raises the staff operational level, the enhancement sense of responsibility.(2) working surface fault measure.Adjusts between the working surface and the fault the included angle; The coal mining machine coal cutting will be prompt from now on moves the frame, will manage the good roof; The working surface support carries on supports and protects in advance; Controls the working surface cycle to press; If the nose appears partial braves to go against time, must select promptly goes against protects goes against; The belt pressure scratches goes against moves the frame; The coal wall hits supposes the wooden anchor rod, guards against the cave-in of sides of a mine tunnel; When necessity, hangs the I-steel on the support to be throat Liang; The attention hangs Liang, prevented the support drills the bottom.(3) working surface fold measure.The adjustment fold axial both sides slope, the government leader when is big to the both sides slope, suitably leaves a stub the coal, when the axial both sides slope is small, should the suitable broken bottom, guarantee the axial both sides slope to be gentle; Adjusts the support as necessary, prevented the support is crooked; Enhancement fold section working surface roof management.(4) prevented the scraper conveyer leaps up moves the measure.The coal mining machine driver, moves a labor, pushes sneaks off one's job should coordinat e, to guarantee the working surface “straight closely three one even”; Controls the working surface top and bottom two lanes to push the progress; When the working surface support appears the incline, must square promptly; The working surface discovered when the scraper conveyer has the glide tendency, should fling the knife promptly or catch up with slides; Using the support side guard shield, adjusts the scraper conveyer, above the impediment leaps up glides down; The embedment sells or installs the hoisting jack, prevented the scraper conveyer leaps up moves; Selects the reasonable feed method, prevented on the scraper conveyer flees glides down.Fifth, conclusion(1) this set independently develops and the improvement synthesis picks the equipment the success application, has laid the solid foundation for the thin coal bed synthesis mechanization mining realization high and stable yield. Also equips this equipment fund aspect to invest is 1,088,000,000 Yuan, the equipment does not invest into the equipment coal plow working surface 1/10.(2) optimizes picks the craft parameter, strengthens the scene management, realization maximum daily production 3504t, the average month produces 89636t, created the roller thin coal bed synthesis to pick the unit to yearly produce 1,000,000 ton new levels.(3) applied the thin coal to pick the synthesis to pick the working surface working procedure reasonable match the safeguard technology measure, has realized the working surface equipment common control, strengthened the production management, the breakdown diagnosis and the accident platoon looks up.Had guaranteed the working surface various working procedures best match, enhanced the working surface operation percentage.【中文翻译】1薄煤层综采设备的研制及工艺参数优化主要探讨了枣庄矿业集团公司自行研制的薄煤层综采设备在田陈矿的成功应用，并对其配套设备的技术改造及技术特征、工作面地质条件、综采设备的工艺参数优化及工作面工序合理匹配的保障技术措施进行了深入分析与介绍。
长臂式采煤用的采煤机的外文翻译、中英文翻译、外文翻译
附录一（英文）I.SHEARER LOADERS FOR LONGWALL MININGIn Europe，longwall mining is comprehensively mechanized by the almost exclusive use of shearer loaders and ploughs. In the Federal Republic of Germany ploughing has been applied to a greater extent than in other coutries .In spite of this ，the proportion of coal extracted by shearer loaders is steadily increasing .It accounted for 36 percent of the total national output in October 1977.There are a number of convincing reasons why shearer loaders are gaining ground. Their operation is essentionly more independent of the floor and roof conditions ，dirt bands and changing seam conditions than that of ploughs. Optimum adaptation of the cutting height，the fixed cutting depth，and better roof control are further arguments in favour of shearer loaders.In October 1976 the effective working time on a plough face was in the range of 35 percent ，compared with 48 percent on a shearer face. The average outputs reflect the aboxe figures (FRG October 1977—1130 t from a plough face ，1678 t from a shearer face).It should be noticed ，however，that shearer loaders are generally operating in seams of greater thickness.Shearer loaders are now available for seams ranging from 0.75 m to 4.50 m in thickness. The various machine versions for the respective operating conditions encountered are assembled from a great number of major components in accordance with the unit principle of construction.Eickhoff shearer loaders，for instance，can be equipped with longitudinal motors having ratings of 170，200，and 300 kw ，and 450 kw at present and 230 kw units will be available soon.The shearers travel on or alongside the conveyor . Ranging arms of different length from 740 mm to 2230 mm are available .The shearers can be manufactured to operate on various voltages and frequencies generally used ，with various haulage methods and speeds，and different drum speeds and drum design for various machine heights.Contrary to former years the manufacturers of such machines are therefore no longer in a position to produce identical machines in large series ，but are compelled to assemble the mining machines from a large number of existing components according to principles which require continuous revision and improvement ，and to integrate them into complete systems together with the face conveyor and roofsupports as required by the mining conditions encountered.Although a high degree of development and great operational safety for the severe operating conditions underground have already been reached，efforts have to be made to develop the mining machines further with a view to meet the following future requirements：(1)—increased outputs (and at the same time a further improvement in operational safety )，(2)—Extension of the working range (e.g. into steeply inclined seams )，(3)—Improvement of the ergonomical conditions (e.g. reduction of dust make and noise ).Increased OutputsThe current trend is for more coal to be extracted from fewer faces.The output from some faces is already so high that even short stoppages on a face result in an enormous loss of output .The required increase of outputs from shearer loaders is therefore closely connected with the requirement for higher operational safety ，a better degree of utilisation and easier monitoring of all functions of the machine .The improvement in performance is therefore not limited to the development of more powerful motors ，haulgeaboxes ，gearheads，and ranging arms ，but also includes the electrical monitoring of the machines and eventually full automation.This also applies to the development of cutting tools，as the tool life and the tool costs are decisive for the performance of a machine .Outputs can also be increased by multi-machine operation on a face .The efficiency can be improved by the elimination of stable holes and by avoiding stoppages caused ，for instance ，by large lumps breaking out of the face and which must be crushed manually.It is also obvious that the limitation of the operating voltage to 1000 v sets a limit to performance and that the further increase of the nominal motor ratings will require the introduction of higher voltages.Extension of the Working RangeComprehensive experience has been gained with shearer loaders in level and slightly inclined seams or workings to the rise.The mining of thin seams is affected by inherent limitations set by the height of the conveyor ，the necessary clearance underneath the machine ，and the height ofthe machine itself .Thin seams can therefore only be extracted by shearer loaders if the machine travels alongside the conveyor. This results in guiding problems which can not be solved by the use of a guiding arrangement provided in the traveling track only. A solution eventually found was to trap the machine against the conveyor. This opened possibilities for the shearer loader in a seam thickness which so far was reserved for the plough .A great number of EDW—170—LN shearers are now operating ，particularly in Great Britain where they extract thin seams of high-grade coking coal .In steeply inclined seams the use of shearer loaders has been limited due to haulage difficulties，and finding adequate safety devices to retain the shearer on the gradient .New developments which dispense with additional safety devices outside of the machine and which provide for the necessary haulage arrangements have extended the working range of shearer loaders into steeply inclined seams .The cost of roadway drivage and maintenance increase considerably with the depth of the workings. The development of advanced heading has so far impeded face advance .The chainless haulage system for shearer loaders now allows for multimachine operation .Within such a system face and machines can be used which are designed for the purpose and which thus not only eliminate stable holes ，but also cut the roadway section，so that high outputs are achieved with the resulting increased productivity .Improvement of Ergonomical Conditions UndergroundCompared with other industrial activities，working underground is particularly laborious and dangerous. Efforts are therefore being made to ease the tasks and to increase the safety of the workings underground not only because of the necessity to obtain people who are willing to operate the equipment .This also urges the need for further development .For many years the problem of dust suppression on shearer loader faces has been a concern ，and much remains to be done in this field .In this connection，reference is lately often made to the hydraulic extraction of coal by water jets or to the use of water jets for assisting conventional mining machine .Underground operations are continuously jeopardized by the occurrence of fire damp .To eliminate such hazards hollow shaft ventilation is frequently used in the U.K. for feeding water and air into the depth of cut by means of Venturi spray jets.The operation of shearer loaders is also improved by the provision of controls ateach end of the machine by radio control ，and by automatic control enabling independent operation of the shearer on the face .COMPONENTS OF SHEARER LOADERSThe targets of development outlined in the foregoing call for continuous improvement and further development of all machine components.Motors：High outputs require high motor ratings .An optimum machine adaptation must be employed for each particular type of coal to keep the specific energy at a minimum .The accommodation of high ratings within the limited space necessitates the use of water-cooled motors .Whilst cooling the stators of motors is now an accepted standard and end-shield cooling is applied for the latest motor designs ，trials are now also being made to increase the motor rating further within a given space by cooling the shafts.The motors used so far for longwall power loading machinery are three-phase induction motors which due to their design are sufficiently robust to meet the operating conditions underground .In an effort to reduce the specific energy to a minimum it is necessary to coordinate the drum speed with the traveling speed of the power loader ，and this could be achieved by a machine equipped with d.c. motors for powering the drums which is said to have been developed in the USSR，although there is no information of the operating results.The motors of conventional shearer loaders are positioned in the longitudinal axis of the machine and require a shaft at either side for power transmission to the gearheads. Such machines therefore require a complex gearing system which ，however ，offers the advantage that the motor power can be divided among the two drums and the haulage box as required .New machines such as ，for instance ，the EDW-150-2L are equipped with transverse motors fitted direct to the ranging arm .The advantage ，however ，is achieved at the expense of the power distribution the two drums which is no longer possible ，and the drum which is subjected to the higher load determines the traveling speed of the shearer by marking full use of its motor power .Haulage UnitsHydraulic haulage units for power loaders have been used for nearly 30 years now .In the course of the decades they have been improved to a high degree of theshearer as a function of the lood on the motor and the haulage box (Eicomatik).They prevent overloads and operate safely using flame-resistant fluids .However ，the development of the semi-conductor technique has progressed to a stage during the last decade that it is now possible to design electrical haulage units powered by d.c. motors the speed of which is controlled by thyristors .Compared with hydraulic haulage units electric haulages are simpler and maintained via the use of plug in control units .In addition ，their various functions are monitored and they respond more rapidly to speed alterations than hydraulic haulage units . Amongst the first power loaders equipped with such electric haulage units are the Eickhoff double-ended ranging drum shearers EDW-150-2L，and the electric haulages have fully met the expectations from the very first installation.Chainless Haulage SystemsAfter the use of haulage ropes and chains ，chainless haulage systems are now gaining ground .They offer the advantages of greater safety ，of a steadier machine operation ，and of multi-machine operation on a face .In Great Britain，a number of various designs are used .A problem connected with some chainless haulage systems is the fact that they impede the flexibility of the face conveyor and can cause operational restrictions.The Eicotrack system of Gebr. Eickhoff has overcome this problem，because contrary to other systems the rack sections have half the pan length ，so that displacements and deflections between the line pans have only half the effect between the rack sections .This unique advantage naturally entails higher costs .In special cases，however ，the flexibility of the face conveyor is still not considered sufficient .In such cases，the rack sections are not fixed to the face accessories ，but are slidingly arranged in a channel or at the trapping tube .This fully eliminates any effect on the flexibility of the conveyor .Depending on the conditions ，the line of rack sections is fixed at one or several points along the face.Existing haulage units can be converted for operation via Eicotrack .Haulage forces of up to 300 KN are currently ased for present-day power loaders . But even these forces are sometimes insufficient for heavy machines in steeply inclined seams. Higher haulage forces are obtained if booster haulage units are installed in addition to an existing haulage unit to house an additional hydraulic motor and with the follow up train of gear wheels .The oil flow from the pump in the main haulage unit is then distributed to the two hydraulic motors which transmit the power to the two rackwheels .This hydraulic arrangement ensures that both rack wheels exert the same force on to the rack .Higher haulage forces are therefore reached at the expenses of correspondingly reduced traveling speed.Gear BoxesShearers powered by longitudinal motors need gearboxes to which the ranging arms with the planetary gearings can be mounted .The gearheads are built in different sizes in accordance with the existing motors and house the bevel wheels ，lubrication pumps and hydraulic pumps . Oil cooling is required for high ratings .Intermediate ，two-speed gearboxes are available when a lower drum speed is required .It is unavoidable ，however，that low drum speeds result im a higher torque load on the gearings at a given rating . All two-speed gearboxes known so far can therefore not operate at full load and should therefore be protected against overloads. However ，the trend for low drum speeds is quite obvious ，and new developments must be planned from the beginning to transmit the full motor power at low speeds. Ranging ArmsRanging Arms in many different lengths are available for shearer loaders .For face end machines ，for instance ，extra long ranging arms ，sometimes obtained by bolting two together ，can be installed .Here again ，oil circulation and oil cooling are required for the transmission of high powers .The low drum speed is now finally reached at the end of the ranging arm in the planetary gearing .If the requirement for low drum speeds continues in the future ，even higher reduction ratios and loads must be coped with by the planetary gearing .If ，in addition ，the use of hollow shafts increases with dimensions foe a sufficient air flow to ensure adequate ventilation ，the only practical solution seem to be double planetary gearings . Meeting such requirements will lead to very complex and expensive designs .Electrical EquipmentWith the almost universal use of shearer loaders for longwall mining and the demand for increased productivity the demand for monitoring and control functions has become extremely urgent .The realization of this however ，has only become feasible after the introduction of instrinsically safe electronics . The latest machines are therefore equipped with s great number of sensors at various points to detect and indicate conditions of temperatures ，pressures，flow rates ，circulation，voltages etc. On Eickhoff shearer loaders the monitored functions are relayed to function indicators whichprovide the facility for obtaining the desired information by means of selectivepush-buttions and digital read-outs.Considerable progress still has to be achieved in the field of horizon control .So far ，there is no reliable and operationally safe method for horizon control which would enable the shearer to cut automatically along the roof or floor line . All concepts and designs conceived and tried so far have not had the expected success ，although the height control of the drums of s shearer is now possible .A programmed shearer loader was already shown by Eickhoff during the 1976 mining exhibition in Dusseldort .Still lacking full automatic horizon control ，the system is based on manually measureing the actual roof and floor cutting horizons along the face at predetermined intervals .and if satisfactory ，programming the shearer so that the cutting profile is respeated during successive shears .Electrical supply to shearer loaders has ben improved in the course of the last years .The shearer cables originally used had no armouring and were therefore vulnerable to mechanical damage when guided in the open spill plate channel .Shearer cables have therefore been provided with a steel mesh armouring or they are protected by a cable handling chain .It must be noted ，however ，that the failure rate of shearer cables is often complained about and that in steeply inclined seams neither the armoured shearer cable in the handling chain offer acceptable solutions .The cable carrier operating in a closed channel of the spill plate developed within a research program sponsored by the Federal Minister for Economy is therefore recognized as the better solution .The production of this idea by Eickhoff and the first installation in a steeply inclined seam at Erin Colliery of Eschweiler showed good results. The shearer cable and the water house are held tight in the channel from the maingate by a pulley in the cable carrier by maintaining an even pull. Hence ，the cable is no longer subjected to torsion at the cable entry into the shearer loader .The operating lift of the shearer cable has thereby been considerably extended.附录二（译文）长臂式采煤用的采煤机长臂式采煤在欧洲已普遍机械化，几乎全部使用采煤机和刨煤机。
MineSafety煤矿安全大学毕业论文英文文献翻译及原文
毕业设计（论文）外文文献翻译文献、资料中文题目：煤矿安全文献、资料英文题目：Mine safety文献、资料来源：文献、资料发表（出版）日期：院（部）：专业：班级：姓名：学号：指导教师：翻译日期： 2017.02.14附录：外文资料与中文翻译外文资料：Mine safetyCoal mining historically has been a hazardous occupation but, in recent years, tremendous progress has been made in reducing accidental coal mine deaths and injuries.the main aspect is as following：⑴ Safety of mine ventilation•Purposes of Mine Ventilation•Properly engineered control of the mine atmosphere is required to: •provide fresh air (oxygen) for men to breathe•provide a source of oxygen for internal combustion engines in machinery •dilute atmospheric contaminants to acceptable levels•maintain temperature and humidity within acceptable limits•remove atmospheric contaminants from the mine.Mine ventilation is twofold in purpose: first, it maintains life, and secondly it carries off dangerous gases. The historic role of ventilation was to provide a flow of fresh air sufficient to replace the oxygen consumed by the miners working underground. Today's mine ventilation primarily deals with noxious gases (mainly generated by trackless equipment underground).Canaries are said to have been used to detect gas in coal mines in the earlystages of coal mining. This sensitive bird would be taken into the workings and, if it perished, the colliers would immediately leave the mine.In the 1920s the hand-turned fans were replaced with air-powered small turbine fans. Large fans of the suction type were placed on the surface and gradually increased in size. Air from surface compressors was piped into the mine to power machinery and to assist in ventilation.Unless the air is properly distributed to the face, the mine ventilation system is not performing its primary function [1]. While it has always been recognized that this last part of ventilation is the most import, it is also the most difficult to achieve.The primary means of producing and controlling the airflow are also illustrated on Figure 1. Main fans, either singly or in combination, handle all of the air that passesthrough the entire system.These are usually, but notnecessarily, located onsurface, either exhaustingair through the system asshown on Figure 1 or,alternatively, connected todowncast shafts or mainintakes and forcing air into and through the system. Because of the additional hazards of gases and dust that may both be explosive, legislation governing the ventilation of coal mines is stricter than for most other underground facilities. In many countries, the main ventilation fans for coal minesare Figure 1. Typical elements of a main ventilation systemrequired, by law, to be placed on surface and may also be subject to other restrictions such as being located out of line with the connected shaft or drift and equipped with "blow-out" panels to help protect the fan in case of a mine explosion.Stoppings and Seals:In developing a mine, connections are necessarily made between intakes and returns. When these are no longer required for access or ventilation, they should be blocked by stoppings in order to prevent short-circuiting of the airflow. Stoppings can be constructed from masonry, concrete blocks or fireproofed timber blocks. Prefabricated steel stoppings may also be employed. Stoppings should be well keyed into the roof, floor and sides, particularly if the strata are weak or in coal mines liable to spontaneous combustion. Leakage can be reduced by coating the high pressure face of the stopping with a sealant material and particular attention paid to the perimeter. Here again, in weak or chemically active strata, such coatings may be extended to the rock surfaces for a few metres back from the stopping. In cases where the airways are liable to convergence, precautions should be taken to protect stoppings against premature failure or cracking. These measures can vary from "crush pads" located at the top of the stopping to sliding or deformable panels on prefabricated stoppings. In all cases, components of stoppings should be fireproof and should not produce toxic fumes when heated.As a short term measure, fire-resistant brattice curtains may be tacked to roof, sides and floor to provide temporary stoppings where pressure differentials are low such as in locations close to the working areas.Where abandoned areas of a mine are to be isolated from the currentventilation infrastructure, seals should be constructed at the entrances of the connecting airways. If required to be explosion-proof, these consist of two or more stoppings, 5 to 10 metres apart, with the intervening space occupied by sand, stone dust, compacted non-flammable rock waste, cement-based fill or other manufactured material. Steel girders, laced between roof and floor add structural strength. Grouting the surrounding strata adds to the integrity of the seal in weak ground. In coal mines, mining law or prudent regard for safety may require seals to be explosion-proof.Doors and airlocks：Where access must remain available between an intake and a return airway, a stopping may be fitted with a ventilation door. In its simplest form, this is merely a wooden or steel door hinged such that it opens towards the higher air pressure. This self-closing feature is supplemented by angling the hinges so that the door lifts slightly when opened and closes under its own weight. It is also advisable to fit doors with latches to prevent their opening in cases of emergency when the direction of pressure differentials may be reversed. Contoured flexible strips attached along the bottom of the door assist in reducing leakage, particularly when the airway is fitted with rail track.Ventilation doors located between main intakes and returns are usually built as a set of two or more to form an airlock. This prevents short-circuiting when one door is opened for passage of vehicles or personnel. The distance between doors should be capable of accommodating the longest train of vehicles required to pass through the airlock. For higher pressure differentials, multiple doors also allow the pressure break to be shared between doors. Mechanized doors, opened by pneumatic or electrical means are particularlyconvenient for the passage of vehicular traffic or where the size of the door or air pressure would make manual operation difficult. Mechanically operated doors may, again, be side-hinged or take the form of rollup or concertina devices. They may be activated manually by a pull-rope or automatic sensing of an approaching vehicle or person. Large doors may be fitted with smaller hinged openings for access by personnel. Man-doors exposed to the higher pressure differentials may be difficult to open manually. In such cases, a sliding panel may be fitted in order to reduce that pressure differential temporarily while the door is opened. Interlock devices can also be employed on an airlock to prevent all doors from being opened simultaneously.Cfd applied to ventilation sys tems：Due to recent advances in computer processing power CFD has been used to solve a wide range of large and complex flow problems across many branches of engineering (Moloney et. al. 1997/98/99). The increase in processor speed has also enabled the development of improved post processing and graphical techniques with which to visualize the results produced by these models. Recent research work has employed CFD models, validated by scale and full-scale experiments, to represent the ventilation flows and pollutant dispersion patterns within underground mine networks. In particular, studies by Moloney (1997) demonstrated that validated CFD models were able to successfully replicate the ventilation flows and gaseous pollutant dispersion patterns observed within auxiliary ventilated rapid development drivages. CFD has proven a capable method by which to identify detailed characteristics of the flow within critical areas such as the cutting face. The results produced by the CFD models were able to demonstrate the relativeefficiency of the different auxiliary ventilation configurations in the dilution, dispersion and transport of the methane and dust from the development face. Further recent studies by Moloney et. al. (1999) have demonstrated that such validated CFD models may be used to simulate the airflow and pollutant dispersion data for a wide range of mining and ventilation configurations. Each simulation exercise produces large sets of velocity, pressure and pollutant concentration data.⑵ Fires Methods of ControlFires that occur in mine airways usually commence from a single point of ignition. The initial fire is often quite small and, indeed, most fires are extinguished rapidly by prompt local action. Speed is of the essence. An energetic ignition that remains undetected, even for only a few minutes, can develop into a conflagration that becomes difficult or impossible to deal with. Sealing off the district or mine may then become inevitable.The majority of fires can be extinguished quickly if prompt action is taken. This underlines the importance of fire detection systems, training, a well-designed firefighting system and the ready availability of fully operational firefighting equipment. Fire extinguishers of an appropriate type should be available on vehicles and on the upstream side of all zones of increased fire hazard. These include storage areas and fixed locations of equipment such as electrical or compressor stations and conveyor gearheads. Neither water nor foam should be used where electricity is involved until it is certain that the power has been switched off. Fire extinguishers that employ carbon dioxide or dry powders are suitable for electrical fires or those involving flammable liquids.Deluge and sprinkler systems can be very effective in areas of fixed equipment, stores and over conveyors. These should be activated by thermal sensors rather than smoke or gas detectors in order to ensure that they are operated only when open combustion occurs in the near vicinity.Except where electricity or flammable liquids are involved, water is the most common medium of firefighting. When applied to a burning surface, water helps to remove two sides of the fire triangle. The latent heat of the water as it vapourises and the subsequent thermal capacity of the water vapour assist in removing heat from the burning material. Furthermore, the displacement of air by water vapour and the liquid coating on cooler surfaces help to isolate oxygen from the fire.⑶ Methods of Dust ControlThe three major control methods used to reduce airborne dust in tunnels and underground mines: ventilation, water, and dust collectors.Ventilation air reduces dust through both dilution and displacement. The dilution mechanism operates when workers are surrounded by a dust cloud and additional air serves to reduce the dust concentration by diluting the cloud. The displacement mechanism operates when workers are upwind of dust sources and the air velocity is high enough to reliably keep the dust downwind.① Dilution Ventilation. The basic principle behind dilution ventilation is to provide more air and dilute the dust. Most of the time the dust is reduced roughly in proportion to the increase in airflow, but not always. The cost of and technical barriers to increased airflow can be substantial, particularly where air already moves through ventilation ductwork or shafts at velocitiesof 3,000 ft/min or more.②Displacement Ventilation. The basic principle behind displacement ventilation is to use the airflow in a way that confines the dust source and keeps it away from workers by putting dust downwind of the workers. Every tunnel or mine passage with an airflow direction that puts dust downwind of workers uses displacement ventilation. In mines, continuous miner faces or tunnel boring machines on exhaust ventilation use displacement ventilation. Enclosure of a dust source, such as a conveyor belt transfer point, along with extraction of dusty air from the enclosure, is another example of displacement ventilation. Displacement ventilation can be hard to implement. However, if done well, it is the most effective dust control technique available, and it is worth considerable effort to get it right. The difficulty is that when workers are near a dust source, say, 10 to 20 ft from the source, keeping them upwind requires a substantial air velocity, typically between 60 and 150 ft/min. There is not always enough air available to achieve these velocities.③ Water sprays. The role of water sprays in mining is a dual one: wetting of the broken material being transported and,airborne capture. Of the two, wetting of the broken material is far more effective.Adequate wetting is extremely important for dust control. The vast majority of dust particles created during breakage are not released into the air, but stay attached to the surface of the broken material. Wetting this broken material ensures that the dust particles stay attached. As a result, adding more water can usually (but not always) be counted on to reduce dust. For example, coal mine operators have been able to reduce the dust from higher longwallproduction levels by raising the shearer water flow rate to an average of 100gpm. Compared to the amount of coal mined, on a weight basis, this 100gpm is equivalent to 1.9% added moisture from the shearer alone. Unfortunately, excessive moisture levels can also result in a host of materials handling problems, operational headaches, and product quality issues, so an upper limit on water use is sometimes reached rather quickly. As a result, an alternative to simply adding more water is to ensure that the broken material is being wetted uniformly.⑷ Mine DrainageWater invades almost every mine in the form of ：direct precipitation (rain and snow), surface runoff, underground percolation. Flows of water have an important effect on the cost and progress of many mining operations and present life and property hazards in some cases.Means of Mine-water Control（Mine Drainage）:As shafts and other mine openings extend below the water table, water is likely to be encountered and to seep into the openings to an extent depending upon the area of rock surface exposed, the hydrostatic pressure, and other factors. In order to continue mining operations, it is therefore necessary to lower the ground water level in the vicinity of the mine by artificial means to keep the workings free of water as well as preventing the flow of surface water into the (surface or underground) mine. This operation is known as mine drainage.Means of mine drainage are limited by circumstances and objectives. The following types of mine-water control can be used singly or more effectively in combination:① Locate shafts or excavations in best ground and protect from direct water inflow from surfaces.② Divert or drain water at or near surface.③Reduce permeability of rock mass by grouting with special types of cement, bentonite and liquid chemical grouts (water sealing).④ Case or cement exploration drill holes.⑤Drill pilot holes in advance of work wherever there may be sudden influents at rates potentially inconvenient.⑥Dewater bedrock at depth by pumping through dewatering wells or from an accessible place in the mine.。
- 1、下载文档前请自行甄别文档内容的完整性，平台不提供额外的编辑、内容补充、找答案等附加服务。
- 2、"仅部分预览"的文档,不可在线预览部分如存在完整性等问题,可反馈申请退款(可完整预览的文档不适用该条件!)。
- 3、如文档侵犯您的权益，请联系客服反馈,我们会尽快为您处理(人工客服工作时间：9:00-18:30)。
附录A简介：煤炭是我国的主要能源，在我国一次性能源中占76％以上。
煤系地层大多形成与还原环境，煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，使水呈酸性，形成酸性矿井水。
对地下水以及其它环境和设施等造成一定的环境影响和破坏。
本文对酸性矿井水的危害、形成原因以及对酸性矿井水的预防和治理进行了简单的阐述。
关键字：采煤活动酸性矿井水环境影响预防治理1前言煤炭是我国的主要能源，在我国一次性能源中占76％以上，必定要进行大量的采煤。
采煤过程中破坏了煤层所处的环境，使其原来的还原环境变成了氧化环境。
煤炭中一般都含有约0.3％～5％的硫，主要以黄铁矿形式存在，约占煤含硫量的2/3。
煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，生成硫酸和氢氧化铁，使水呈现酸性，即生产了酸性矿井水。
PH值低于6的矿井水称酸性矿井水。
酸性矿井水在我国部分煤矿特别使南方煤矿分别较为广泛。
我国南方煤矿的矿井水pH值一般在2.5～5.8，有时达2.0。
pH值低的原因与煤中含硫量高有密切关系。
酸性矿井水的形成对地下水造成了严重的污染，同时还会腐蚀管道、水泵、钢轨等井下设备和混凝土井壁，也严重污染地表水和土壤，使河水中鱼虾绝代，土壤板结，农作物枯萎，影响人体健康。
1 酸性矿井水的危害矿井水的pH值低于6即具有酸性，对金属设备有一定的腐蚀性；pH值低于4即具有较强的腐蚀性，对安全生产和矿区生态环境产生严重危害。
具体有以下几个方面：1>腐蚀井下钢轨、钢丝绳等煤矿运输设备。
如钢轨、钢丝绳受pH值<4的酸性矿井水侵蚀，十几天至几十天其强度会大大降低，可造成运输安全事故；2>探放pH值低的老空水，铁质控水管道和闸门在水流冲刷下腐蚀很快.3>酸性矿井水中SO42-含量很高，与水泥中某些成分相互作用生成含水硫酸盐结晶。
这些盐类在生成时体积膨胀。
经测定，当SO42-生成CaSO4·2H2O时，体积增大一倍；形成MgSO4·7H2O时，体积增大430％；体积增大使混凝土构筑物结构.4>酸性矿井水还是环境污染源。
酸性矿井水排入河流，pH质小于4时，会使鱼类死亡；酸性矿井水排入土壤，破坏土壤的团粒结构，使土壤板结，农作物枯黄，产量降低，影响工农关系；酸性矿井水人类无法饮用，长期接触，可使人们手脚破裂，眼睛痛痒，通过食物链进入人体，影响人体健康。
2 酸性矿井水形成的原因煤系地层大多形成于还原环境，含黄铁矿（FeS2）的煤层形成于强还原环境。
煤炭中一般都含有约0.3％～5％的硫，主要以黄铁矿形式存在，约占煤含硫量的2/3。
煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，生成硫酸和氢氧化铁，使水呈现酸性，即生产了酸性矿井水。
酸性矿井水形成的主要原因即发生的主要化学反应如下：1> 黄铁矿氧化生成游离硫酸和硫酸亚铁：2FeS2＋7O2+2H2O2H2SO4+2FeSO42> 硫酸亚铁在游离氧的作用下转化为硫酸铁：4FeSO4＋2H2SO4＋O22Fe2（SO4）3＋2H2O3> 在矿井水中，硫酸亚铁的氧化作用，有时也不一定需要硫酸：12FeS2＋3O2+6H2O4Fe2（SO4）3＋4Fe（OH）34> 矿井水中硫酸铁，具有进一步溶解各种硫化矿物的作用：Fe2（SO4）3＋MS＋H2O＋3/2 O2M SO4+2FeSO4＋H2SO5> 硫酸铁在弱酸性水中发生水解而产生游离硫酸：Fe2（SO4）3+6H2O 2 Fe（OH）3＋3H2SO46> 在矿井深部硫化氢含量高时，在还原条件下，富含硫酸亚铁的矿井水也可产生游离硫酸：2FeSO4＋5H2S 2 FeS2＋3S＋H2SO4＋4 H2O酸性矿井水的性质除与煤中含硫量有关外，还与矿井水涌水量、密闭状态、空气流通状况、煤层倾角、开采深度及面积、水的流动途径等地质条件和开采方法有关。
矿井涌水量稳定，则水的酸性稳定；密闭差、空气流通良好，则水的酸性较强，Fe3+离子含量较多；反之，则酸性较弱，Fe2+离子较多；开采越深，煤的含硫量越高；开采面积越大，水的流经途径越长，则氧化、水解等反应进行得越充分，水的酸性越强，反之则弱。
3 酸性矿井水的预防与治理3·1 酸性矿井水的预防根据酸性矿井水形成的条件和原因，可以从减源、减量、减时等三个方面进行预防或减轻其危害程度。
1>减源：捡选利用造酸矿物，化害为利。
煤矿床的主要造酸矿物时夹杂在煤层中的黄铁矿结核和煤本身的含硫量。
煤的开采率低、残留煤柱或浮煤丢失多，黄铁矿结核废弃在井下采空区中，被积水长期浸泡，是产生酸性水的重要根源。
减少工作面丢失的浮煤、积极捡选利用黄铁矿结核，能减少产生酸性水的物质。
拦截地表水，减少入渗量。
例如回填矸石，控制顶板，防止地面水沿塌陷裂隙浸入老空区。
在井下，特别是老井或废弃封闭井巷处，对矿井水施放适量的抑菌剂，抑制或杀灭微生物的活性，或者减少矿井水中微生物的数量。
通过降低微生物对硫化物的有效作用，达到控制酸性矿井水生成的目的。
2>减少排水量：设立专门排水系统，集中排酸性水，并在地表拦蓄起来，使其蒸发、浓缩，而后加以处理，免除污染。
3>减少排放酸性水的时间：减少矿井水在井下的停留时间，可在一定程度上降低微生物对煤中硫化物的氧化作用，从而有助于减少酸性矿井水的形成。
对含黄铁矿多、硫分高、地表水渗漏条件又好的浅部煤层，或已形成强酸性水的老窖积水区，在开拓布局上要权衡利弊，统筹安排，在矿井前期不予开采或探放，留待矿井水末期处理，避免长期排放酸性水。
3·2 酸性矿井水的治理在一定地质条件下，酸性水中的硫酸可与钙质岩石或其它基性矿物发生中和反应而降低酸度。
用烧碱作中和剂用量少，污泥生成也少，但水的总硬度往往很高，虽降低了水的酸度，但增加了硬度，而且成本高，现已基本不用。
目前，处理方法有以石灰乳为中和剂的方法、石灰石为中和剂的方法以及石灰石——石灰法、微生物法和湿地处理法。
石灰乳中和剂处理法适用于处理酸性较强、涌水量较小的矿井水；石灰石——石灰法适用于各种酸性矿井水，尤其是当酸性矿井水中的Fe2+离子较多时适用，还可以减少石灰用量；微生物法基本原理时应用氧化铁细菌进行氧化除铁，此菌能从水生环境中摄取铁，然后以氢氧化铁形式把铁沉淀子在它们的粘液分泌物中，时酸性水的低铁转化为高铁沉淀出来，然后再用石灰石中和游离硫酸，可降低投资，减少沉渣。
湿地法又称浅沼泽法，此法具有成本低、易操作、效率高等优点，具体方法在这里不再详述。
结论煤系地层大多形成与还原环境，煤层开采后处于氧化环境，流铁矿与矿井水和空气接触后，经过一系列的氧化、水解等反应，使水呈酸性，形成酸性矿井水。
对地下水以及其它环境和设施等造成一定的环境影响和破坏，同时会对人体健康造成一定的影响。
通过对酸性矿井水的形成原因进行分析，并采取一定的预防和治理措施，可减少酸性矿井水对地下水的污染、其它环境和设施等造成的破坏以及对人体健康的影响。
参考文献：[1]王大纯等主编，《水文地质学基础》，地质出版社，北京.[2]苑眀顺，环境及地下水水力学研究专题论文综述，长江科学院院报，1994，3.[3]林年丰，李昌辉，田春声等，《环境水文地质学》，北京，地质出版社，1990，21.附录BProfile : Coal is China's main energy in the country's total primary energy accounted for 76% and above. Most coal strata formed and restore the environment, coal mining in the oxidizing environment, Flow iron ore mine with water and exposed to the air, after a series of oxidation and hydrolysis, so that water acidic. formation of acidic mine water. On groundwater and other environmental facilities, and so on have a certain impact on the environment and destruction. In this paper, the acidic mine water hazards, and the formation of acid mine water in the prevention and treatment of simple exposition. Keywords : mining activities acidic mine water prevention and correction of the environmental impact of coal a foreword is China's main energy, China accounted for one-time energy above 76%, will conduct extensive mining. Mining process undermined the seam office environment, the reduction of its original environment into oxidizing environment. Coal generally contain about 0.3% ~ 5% of sulfur, mainly in the form of pyrite, sulfur coal accounts for about 2 / 3. Coal mining in the oxidizing environment, flow and iron ore mine water and exposed to the air, after a series of oxidation, hydrolysis reaction to produce sulfuric acid and iron hydroxide, acidic water showed that the production of acid mine water. PH value lower than the six said acidic mine water mine water. Acid mine water in parts of the country in the South in particular coal mine were more widely. South China coal mine water in general pH 2.5 ~ 5.8, sometimes 2.0. Low pH causes and coal of high sulfur closely related. Acid mine water to the formation of ground water have caused serious pollution, while also corrosion pipes, pumps, Underground rail, and other equipment and the concrete wall, but also serious pollution of surface water and soil, river shrimp pictures, soil compaction, crops wither and affect human health. An acidic mine water hazards mine water pH is below 6 is acidic, metal equipment for a certain corrosive; pH is less than 4 has strong corrosive influence on the safety in production and the ecological environment in mining areas serious harm. Specifically, there are the following : a "corrosive underground rail, rope and other coal transport equipment. If rail, rope by the pH value "4 acidic mine water erosion, 10 days to Jishitian its intensity will be greatly reduced, Transport can cause accidents; 2 "prospecting low pH goaf water, Quality Control iron pipes and the gate under the flow erosion corrosion soon.3 "acidic mine water SO42-content high, and cement production of certain components interact water sulfate crystallization. These salts are generated when the expansion. After determination of when SO42-generation CaSO4 • 2H2O, the volume increased by 100%; Formation MgSO4.7H2O, volume increased 430%; Volume increases, the structure of concrete structures.4 "acidic mine water or environmental pollution. Acid mine water isdischarged into rivers, the quality of pH less than 4:00, would fish died; Acidic mine water into the soil, damage granular soil structure, soil compaction, arid crop yields fall, affecting workers and peasants; Acid mine water humans can not drink that long-term exposure, people will limbs broken, eyes suffering, enter the body through the food chain. affect human health. 2 acidic mine water and the reasons are mostly coal strata formed in the reduction environment, containing pyrite (FeS2) formed in the seam-reduction environment. Coal generally contain about 0.3% ~ 5% of sulfur, mainly in the form of pyrite, sulfur coal accounts for about 2 / 3. Coal mining in the oxidizing environment, flow and iron ore mine water and exposed to the air, after a series of oxidation, hydrolysis reaction to produce sulfuric acid and iron hydroxide, acidic water showed that the production of acid mine water. Acidic mine water that is the main reason for forming the main chemical reaction as follows : a "pyrite oxidation and free sulfate ferrous sulfate : 2FeS2 O2 +7 +2 +2 H2O 2H2SO4 FeSO4 2 "ferrous sulfate in the role of oxygen free Under into sulfate : 4FeSO4 +2 Cp'2Fe2 H2SO4 + O2 (SO4) 3 +2 H2O 3 "in the mine water The oxidation of ferrous sulfate, sometimes not necessarily need to sulfate : 12FeS2 O2 +6 +3 H2O 4Fe2 (SO4) 3 +4 Fe (OH) 3 4 "mine water Sulfate is further dissolved sulfide minerals in various roles : Fe2 (SO4) 3 + MS + H2O + / 2 + O2 M SO4 H2SO FeSO4 + 5 " ferric sulfate in the water occurred weak acid hydrolysis sulfate produced free : Fe2 (SO4) 3 +6 H2O two Fe (OH) 3 +3 H2SO4 6 "deep in the mine containing H2S high, the reduction of conditions, the ferrous sulfate-rich mine water can produce sulfuric acid free : 2FeSO4 +5 FeS2 H2S 2 +3 +4 S + H2O H2SO4 acidic mine water in addition to the nature and sulfur coal on the other, with the mine water discharge, confined state, ventilation conditions, seam inclination, mining depth and size, water flow channels and other geological conditions and mining methods. Mine Inflow stability, stability of acidic water; Confined poor, good air circulation, the more acidic the water, Fe3 + ion content more; Instead, the acid is weak, the more Fe2 + ion; more deep mining of coal with a sulfur content higher; The larger the area of mining, water flows through the channel longer, oxidation, hydrolysis reactions from the more full, the water more acidic strong, If not weak. 3 acidic mine water prevention and control • a three acidic mine water under the Prevention of acidic mine water formation conditions and causes from source reduction, reductions, reduced when three aspects to prevent or mitigate damage. 1 "by the source : the seizure election made use of mineral acid, being the case. The main coal-bed mineral create acid when in a mixture of coal pyrite nodules and coal with a sulfur content itself. Coal mining rate is low and residual coal pillars or floating coal lost, abandoned pyrite nodules underground goaf, in which long-term water immersion, Acidic water produced is a major source. Face to reduce the loss of float coal, the use of positive seized election pyrite nodules, can reduce the productionof acidic water substances. Intercept surface water, reduce infiltration. For example, the filling of waste, control of roof to prevent collapse fissures along the surface water immersion goaf. In Underground, particularly old or abandoned wells closed shaft, the mine water discharge appropriate antibacterial agent, kill or inhibit microbial activity, or reduce the microbial mine water quantity. By reducing microbial sulfide on the effective role and to control the generation of acid mine drainage purposes. 2 "reduced discharge : the establishment of specialized drainage system, centralized emission acidic water, and storing up on the surface, it evaporated, condensed, then to be addressed to remove pollution. 3 "to reduce emissions of acid water in time : to reduce the underground mine water in the length of stay, in a certain extent, to reduce the microbial coal oxidation of sulphides, thus helping to reduce acid mine water. Containing pyrite, sulfur, surface water leakage conditions for a good shallow seam, or have formed strong acidic water stagnant water in the old cellar, the pioneering layout to weigh the pros and arrangements, not early in the mine prospecting or mining, leaving the end of mine water treatment avoid long-term emissions acidic water. • 2 3 acidic mine water treatment in certain geological conditions, Acidic water with calcium sulfate rock or other basic mineral occurrence and the reaction decreases acidity. Neutralizer with caustic soda used for less, less sludge is generated, but the total water hardness is often high, while reducing the acidity of the water. However, an increase in the hardness, and the high cost is no longer. Currently, treatment for a neutralizer to the milk of lime, limestone for the neutralizer and limestone -- lime, microbiological method and wetlands treatment. Neutralizer milk of lime treatment method applicable to the handling of a strong acid, Inflow smaller mine water; Limestone -- lime applied to various acidic mine water. especially when acidic mine water Fe2 + ions more applicable, but also can reduce the amount of lime; microbiological method applied when the basic tenets of iron oxide bacterial oxidation than iron, bacteria from the aquatic environment intake of iron, then to form ferric hydroxide precipitation-iron in their mucus secretions, Acidic water at the low iron into high-iron precipitates out and then reuse limestone and free sulfuric acid, can reduce investment, reduce sediment. Wetlands Act also known as shallow marshes, this method is low cost and easy operation, high efficiency, specific methods not go into details here. Conclusions Most coal strata formed and restore the environment, coal mining in the oxidizing environment, Flow iron ore mine with water and exposed to the air, after a series of oxidation and hydrolysis, so that water acidic. formation of acidic mine water. On groundwater and other environmental facilities, and so on have a certain impact on the environment and destruction, Meanwhile harmful to human health caused some influence. Based on the acidic mine water cause analysis, and to take certain preventive and treatment measures, reduce acid minewater pollution in the groundwater, environmental and other facilities and the damage caused to human health effects. References : [1] Wang Chun compiled, "hydrogeology basis," Geological Press, Beijing. [2] Yuan Ming-shun, the environment and groundwater hydraulics research papers on the topic, the Yangtze River Academy of Sciences reported that 1994,3.[3], Lin Feng, Li Changhui, Tian Chunsheng, "environmental hydrogeology," Beijing, geological Press, 1990,21.。