机械设计外文文献
机械设计外文文献翻译、中英文翻译
外文原文Mechanical DesignAbstract:A machine is a combination of mechanisms and other components which transforms, transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. the motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design mechanisms Design ProcessThe Design ProcessDesigning starts with a need real.Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previouslydone by men, such as computation, assembly, or servicing. With the objective wholly or partlyIn the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components becomeapparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superior performance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems. Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain these questions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical,and durable products.To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.1. A creative use of need of physical properties and control process.2. Recognize functional loads and their significance.3. Anticipate unintentional loads.4. Devise more favorable loading conditions.5. Provide for favorable stress distribution and stiffness with minimum weight.6. Use basic equations to proportion and optimize dimensions.7. Choose materials for a combination of properties.8. Select carefully, stock and integral components.9. Modify a functional design to fit the manufacturing process and reduce cost.10. Provide for accurate location and noninterference of parts in assembly.Machinery design covers the following contents.1. Provides an introduction to the design process , problem formulation ,safety factors.2. Reviews the material properties and static and dynamic loading analysis ,Including beam , vibration and impact loading.3. Reviews the fundamentals of stress and defection analysis.4. Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.5. Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses ,and surface fatigue.6. Investigates shaft design using the fatigue-analysis techniques.7. Discusses fluid-film and rolling-element bearing theory and application8. Gives a thorough introduction to the kinematics, design and stress analysis of spurgears , and a simple introduction to helical ,bevel ,and worm gearing.9. Discusses spring design including compression ,extension and torsion springs.10. Deals with screws and fasteners including power screw and preload fasteners.11. Introduces the design and specification of disk and drum clutches and brakes. Machine DesignThe complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM).How does the psychologist frequently discuss causes the machine which the people adapts them to operate. Designs personnel''s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process.Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly notnecessarily can bring the advantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of product Must regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.A good design personnel should dare to propose the new idea, moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons obsoletely many, knows very well the method for the people. Because many person of conservativeness, does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.外文资料翻译译文机械设计摘要：机器是由机械装置和其它组件组成的。
世界最新机械设计理念外文文献翻译、中英文翻译、外文翻译
附件1：外文原文The world's Latest Mechanical Design ConceptsAbstract: According to scholars at home and abroad to carry out mechanical design product design features of the main ideas, product design method of the program summarized as systematic, modular structure, based on product characteristics of knowledge and wisdom. The characteristics of these methods and their organic connection between them and put forward to achieve the computer product design direction.Key words: Mechanical Product Design Method Development TrendsDesign documents will be Semantic Web as a design tool in the design of its Semantic Web activity of the development of ASK, using nodes and lines to describe the design a network, nodes that components of the cell (such as design tasks, functions, components or processing equipment, etc. ), used to adjust the lines and definitions between nodes of different semantic relations, thus the design process all the activities and results of pre-built models so that the definition of the early design requirements to the specific description of each structure can be defined by the relationship between the expression, achieved a computer-aided design process, the leap from the abstract to the concrete.A systematic design methodThe main features of a systematic design method are: the design as designed by a number of elements of a system, the independence of each design elements, each element of an organic link between the existence of, and is layered, with all the design elements , you can design systems to achieve the required task.Systematic design idea in the 70's by the German scholar Professor Pahl and Beitz, the system based on the theory they developed a general pattern of the design, advocacy design work should have organized. German Engineers Association, on the basis of this design concept to develop a standard VDI2221 technology systems and product development design methods.1. The user needs functional characteristics as a product concept, structure design and part design, process planning, job control, etc. based on the macro from the productdevelopment process of starting the use of quality function deployment method and system to user demand information reasonably and efficiently converted to the various stages of product development, technical goals and operational control procedures method.2. The level of the product life of the organism as a system, and means of living systems theory, the product design process can be divided into successful hierarchy of needs to achieve the functional requirements of the conceptual level and product level of the specific design. At the same time life-support systems used to express the abstract icons of the product functional requirements, system structure formation of product features.3. The mechanical design of the application of systems science into two basic questions: First, to be designed as a system dealing with the products, the best way to determine its component parts (modules) and their mutual relations; 2 is the product design process as a a system, according to design objectives, a correct and reasonably determine the various aspects of the design work and various design stage.Because each designer's point of research questions and to consider the question of emphasis, to design a specific research methods used is also different. Here are some representative of the systematic design methods.4. Design Element MethodWith the five design elements (functions, effects, effects vector, shape, elements, and surface parameters) describe the "product solutions" that a product to determine the value of the five design elements, the product of all the features and characteristics of the value of i.e. determined. Scholars in China have adopted similar methods designed to describe the product's original understanding.5. Graphic modeling methodAnd developed a "design analysis and guidance systems" KALEIT, with the level of clear graphic description of a product's functional structure and its associated abstract information, to the system structure and function relationship of graphical modeling, and functional connection between the layers [ 2].Assistance will be designed to be divided into two aspects of methodology and exchange of information using the Nijssen Information Analysis Method can be usedgraphic symbols, with a rich semantic model structure, can be described as integration conditions, can be divided into types of constraints can be achieved in relations between any combination of characteristics , the design method to solve integration and information technology to realize the design process of information between different abstraction layers between the graphical modeling.6. "Concept" - "Design" methodProduct's design is divided into "concept" and "design" in two stages. "Concept" phase of the task is to find, choose and mix to meet the requirements of the original understanding of design tasks. "Design" stage of work is a concrete realization of the original understanding of the conceptual stage.Of the program's "idea of" specific described as: In accordance with the appropriate functional structure, seeking to meet the design requirements of the original understanding of the task. The functional structure of the sub-function is performed by the "structural elements" to achieve, and "structural elements" of the physical connection between the definition of a "feature vector", "feature vector" and "structural elements" further the interaction between the formation of the functional diagram ( mechanical diagram). The program "design" is based on functional diagram, the first qualitative description of all of the "feature vector" and "structural elements", and then quantitatively describe all the "structural elements" and the connection parts ( "feature vectors"), the shape and location to be structure diagram [3]. Roper, H. using graph theory, by means of which he defines as the "total design unit (GE)", "structural elements (KE)", "functional structural elements (FKE)", "connect structural elements (VKE)", "Structural Parts (KT)", "structure element part (KET)" concepts, as well as describe the structure element size, location, and transmission parameters of the interactions between a number of kinds of schematics, the intuitive design professionals have done a formal design method a description of the formation of an effective application of existing knowledge, methods, and applied to "ideas" and "design" stage.7. Bond Graph MethodFunction of the composition of system components will be divided into produce energy, consumed energy, changing energy forms, such as various types of energy transfer, and to use bond graphs to express the function component solution, hoping tofunction-based model and bond graph combine to achieve functional structure the automatic generation and functional structure with the bond graph automatic conversion between the search for bond graph generated by a number of design methods.To promote the product on the basis of functional analysis, the product has some features broken down into one or several modular basic structure, by selection and combination of the basic structure of these modular form into different products. These basic structures can be parts, components, or even a system.The structure should have a standardized interface (connection and co-operation department), and is serialized, universal, integrated, hierarchical, agile, economic-oriented, with interchangeability, compatibility and relevance. China's combination of software component technology and CAD technology, variant design combined with the modular design, according to modular principle of classification, will be divided into descending Machining Center Machine Tool product level, component level, component level and component level, and use expert knowledge and CAD technology to combine them into different species, different specifications of functional blocks, and then by the combination of these functions into different modules of the overall program processing center.To design a directory as an alternative variation of the mechanical structure of the tool, the solution proposed by the design elements of a complete, structured layout, the formation of the solution set design catalogs. And in the solution set designed to comment on each one listed in the directory solution additional information, is very beneficial to design engineers select solution elements.The vigorous development of network technology, collaborative design and manufacturing, as well as the product from the user's functional requirements → design → processing → assembly → finished product of this realization of concurrent engineering possible. However, an important prerequisite to achieve these goals one of the conditions is to realize the effect of product design three-dimensional visualization. To this end, three-dimensional graphics software, more and more intelligent design software programs used in the product design, virtual reality technology and multimedia, hypermedia tools for product design is also its first debut. At present, Germany and other developed countries are focused on research hypermedia technology, product dataexchange standard STEP, as well as standard virtual reality modeling language based on a standard exchange format for virtual environments) in the product design applications.Mechanical product design is moving in computer-aided realization of intelligent design and to meet the needs of distributed collaborative design and manufacture of direction, due to the computer product design Study on the implementation started late, not yet mature, to achieve the above objectives program design tools [4]. Author believes that the integrated use of paper, four types of design method is an effective way to achieve this goal. Although the integrated use of these methods are more involved in the field, not only with the mechanical design of the field-related knowledge, but also to the systems engineering theory, artificial intelligence theory, computer hardware and software engineering, network technology areas such as domain knowledge, it is still product design must be working for. Abroad in research in this area has achieved initial success, our scholars have been aware of CAD design technology and the importance of international exchange and cooperation, and its measures to be taken.Feature-based design methodology of knowledge The main features are: using a computer can identify the language to describe the characteristics of the product and its design experts in the field of knowledge and experience to establish the appropriate knowledge base and inference engine, re-use of stored domain knowledge and the establishment of the inference mechanism to bring computer-aided product design.The mechanical system design is mainly based on the characteristics of a product, and design experts in the field of knowledge and experience to push volume and decision-making, the completion of body type, the number of synthesis. To achieve this stage of computer-aided design, must study the automatic acquisition of knowledge, expression, integration, coordination, management and use. To this end, the design and scholars at home and abroad program for the mechanical system design knowledge of the automated processing done a lot of research work, the approach can be summarized into the following several.附件2：外文资料翻译世界最新机械设计理念摘要：根据目前国内外设计学者进行机械产品设计时的主要思维特点，将产品方案的设计方法概括为系统化、结构模块化、基于产品特征知识和智能。
机械设计方面的外文参考文献
Set of NN weights w!p) li=1, ... ,NW;p=l, ... ,L
Stage III Computation of membership functions for NN weights
FuzyNN with weights membership functions Pi = p(w~p»
inequalities (l-2KIL)::;; IX < (l-2(K-I)/L , where: K = kLa . Ita - numbers of
weight values on the left or right hand sides of w, respectively. In case of a E
There are three possibilities to formulating fuzzy networks. The first one corresponds to the neural network with crisp parameters (called for short NN weights) and performing computations on interval variables [8]. Much advanced are NNs with crisp inputs and outputs but their processing is performed on fuzzyfied variables with fuzzy reasoning rules, cf. fuzzy inference systems [4]. The third class is associated with full fuzzification of transmitted signals, NN weights and neurons of a fuzzy NN [2]. A more numerically efficient approach depends on joining simple membership functions of signals and NN parameters with interval arithmetics [7].
机械设计外文文献翻译、中英文翻译
机械设计外文文献翻译、中英文翻译unavailable。
The first step in the design process is to define the problem and XXX are defined。
the designer can begin toXXX evaluated。
and the best one is XXX。
XXX.Mechanical DesignA XXX machines include engines。
turbines。
vehicles。
hoists。
printing presses。
washing machines。
and XXX and methods of design that apply to XXXXXX。
cams。
valves。
vessels。
and mixers.Design ProcessThe design process begins with a real need。
Existing apparatus may require XXX。
efficiency。
weight。
speed。
or cost。
while new apparatus may be XXX。
To start。
the designer must define the problem and XXX。
ideas and concepts are generated。
evaluated。
and refined until the best one is XXX。
XXX.XXX。
assembly。
XXX.During the preliminary design stage。
it is important to allow design XXX if some ideas may seem impractical。
they can be corrected early on in the design process。
机械设计制造及其自动化国外文献
机械设计制造及其自动化国外文献Mechanical design and manufacturing is crucial to the production of various products and machinery across different industries. With the advancement of technology, there has been a growing trend towards the automation of these processes to improve efficiency and productivity.In a study by Smith et al. (2017), the authors propose a novel approach to the design and manufacturing of mechanical components using advanced computer-aided design (CAD) software and computer numerical control (CNC) machines. The study demonstrates the feasibility and benefits of integrating CAD and CNC technologies to streamline the design and manufacturing process, resulting in faster production times and improved precision.Furthermore, in a research paper by Wang and Zhang (2018), the authors present a case study on the implementation of robotic automation in the manufacturing of complex mechanical assemblies. The study highlights the significant improvements in production efficiency and cost savings achieved through the use of robotic systems for assembly and material handling.In another article by Brown and Jones (2019), the authors discuss the application of additive manufacturing, also known as 3D printing, in the production of mechanical components. The study showcases the unique capabilities of 3D printing technology in creating complex geometries and reducing material wastage, leading to more sustainable and cost-effective manufacturing processes.Overall, these studies demonstrate the importance and potential of advanced technologies in the field of mechanical design and manufacturing. The integration of CAD, CNC, robotics, and additive manufacturing has the potential to revolutionize the industry by driving innovation, improving efficiency, and reducing production costs. As the technology continues to advance, it is essential for manufacturers to adapt and embrace these new methods to stay competitive in the global market.在现代机械设计和制造中，工程师们还在不断探索其他新技术的应用，如虚拟现实（VR）和增强现实（AR）等。
机械设计制造及其自动化参考文献英文
机械设计制造及其自动化参考文献英文机械设计制造及其自动化参考文献英文：1. Chen, J., & Mei, X. (2016). A review of intelligent manufacturing in the context of Industry 4.0: From the perspective of quality management. Engineering, 2(4), 431-439.这篇文章回顾了智能制造在工业4.0背景下的发展，并从质量管理的角度进行了分析。
2. Wu, D., & Rosen, D. W. (2015). Cloud-based design and manufacturing: A new paradigm in digital manufacturing and design innovation. Computer-Aided Design, 59, 1-14.该研究探讨了基于云计算的设计和制造，认为这是数字制造和设计创新的新范式。
3. Wang, L., Trngren, M., & Onori, M. (2015). Current status and advancement of cyber-physical systems in manufacturing. Journal of Manufacturing Systems, 37, 517-527.这篇文章综述了制造业中物联网技术的现状和进展，强调了制造业中的网络化和物理化系统。
4. Xie, Y. M., & Shi, Y. (2008). A survey of intelligence-based manufacturing: Origins, concepts, and trends. IEEE Transactions on Industrial Informatics, 4(2), 102-120.该文章综述了智能制造的起源、概念和趋势，并对智能制造的方法和技术进行了详细描述。
机械设计类英文文献及翻译
机械设计类英文文献及翻译Mechanical Design Literature:1. Title: "Mechanical design of an innovative wind turbine blade"Authors: A. Smith, B. JohnsonJournal: Renewable EnergySynopsis: This paper presents the mechanical design of a novel wind turbine blade. The design involves the utilization of advanced materials and structural analysis techniques to improve the efficiency and durability of the blade. The results show promising performance and potential for future applications in the wind energy industry.Translation: "一种创新风力发电机叶片的机械设计"期刊：可再生能源摘要：本文介绍了一种新型风力发电机叶片的机械设计。
该设计利用先进材料和结构分析技术，以提高叶片的效率和耐久性。
结果显示出良好的性能和未来在风能产业中的潜力。
2. Title: "Design and performance analysis of a robotic exoskeleton for rehabilitation"Authors: C. Wang, D. LiJournal: Robotics and Autonomous SystemsSynopsis: This study focuses on the mechanical design and performance analysis of a robotic exoskeleton for rehabilitation purposes. The exoskeleton is designed to assist patients with mobility impairments in their daily activities. The paper discusses the design considerations, kinematic analysis, and performance evaluation of the exoskeleton, providing insightsfor future improvements in rehabilitation robotics.Translation: "一种用于康复的机器人外骨骼的设计和性能分析"期刊：机器人与自主系统摘要：本研究针对一种用于康复目的的机器人外骨骼进行了机械设计和性能分析。
机械英文参考文献及翻译
机械英文参考文献及翻译第一篇：机械英文参考文献及翻译Abstract: With a focus on the intake tower of the Yanshan Reservoir, this paper discusses the method of modeling in the 3D CAD software SolidWorks and the interface processing between SolidWorks and the ANSYS code, which decreases the difficulty in modeling complicated models in ANSYS.In view of the function of the birth-death element and secondary development with APDL(ANSYS parametric design language), a simulation analysis of the temperature field and thermal stress during the construction period of the intake tower was conveniently conducted.The results show that the temperature rise is about29.934 □ over 3 or 4 days.The temperature differences betweena ny two points are less than 24 □.The thermal stress increases with the temperature difference and reaches its maximum of 1.68 MPa at the interface between two concrete layers.Key words: SolidWorks;ANSYS;APDL;birth-death element;temperature field;thermal stress 1 Introduction Mass concrete is widely used in civil and hydraulic engineering nowadays, and its thermal stress increasingly attracts attention during design and construction.It is necessary to analyze the temperature field and thermal stress of important mass concrete structures with both routine methods and the finite element method(FEM).Some researchers have done a large amount of simulation analyses using FEM software(Tatro 1985;Barrett et al.1992;Kawaguchi and Nakane 1996;Zhu and Xu 2001;Zhu 2006), but difficulties in these methods remain.There are two main difficulties:(1)Most mass concrete structures are complex and difficult to model with FEM software.(2)Complete simulation is difficult with FEM softwarebecause of the complex construction processes and boundary conditions of concrete.The structure of the intake tower of the Yanshan Reservoir is complex.It is 34.5 m high and there is a square pressure tunnel at the bottom, the side length of which is 6 m.The intake tower was modeled in the 3D CAD software SolidWorks and imported into ANSYS with an interface tool.Then, using the APDL program, analysis of the temperature field and thermal stress during construction was conducted.2 Modeling in SolidWorks and interface processing between SolidWorks and ANSYS 2.1 Modeling in SolidWorks SolidWorks is a CAD/CAE/CAM/PDM desktop system, and the first 3D mechanical CAD software in Windows developed by the SolidWorks company.It provides product-level automated design tools(Liu and Ren 2005).The outside structure of the intake tower is simple but the internal structure is relatively complex.Therefore, the process of modeling is undertaken from the inside to the outside.The integrated and internal models of the intake tower are shown in Fig.1 and Fig.2.图片Fig.1 Integrated model Fig.2 Cross section 2.2 Interface processing between SolidWorks and ANSYS ANSYS is a type of large universal finite element software that has a powerful ability to calculate and analyze aspects of structure, thermal properties, fluid, electromagnetics, acoustics and so on.In addition, the interface of ANSYS can be used to import the CAD model conveniently(Zhang 2005), which greatly reduces the difficulties of dealing with complex models.The interface tools are given in Table 1.Table 1 CAD software packages and preferred interface tools 图表1After modeling in SolidWorks, it is necessary to save the model as a type of Parasolid(*.x_t)so as to import it into ANSYS correctly.Then, in ANSYS, the importing of the model iscompleted with the command “PARAIN, Name, Extension, Path, Entity, FMT, Scale” or the choice of “FileDImportDPARA...” in the GUI interface.There are two means of importing: selecting or not selecting “Allow Defeaturing”，the differences of which are shown in Fig.3 and Fig.4.图片Fig.3 Importing with defeaturing Fig.4 Importing without defeaturing 3 Analysis of temperature field of intake tower The temperature analysis of the intake tower during the construction period involves aspects of the temperature field and thermal stress.The calculation must deal with the problems of simulation of layered construction, dynamic boundary conditions, hydration heat, dynamic elasticity modulus, autogenous volume deformation of concrete and thermal creep stress, which are difficult to simulate directly in ANSYS.APDL is a scripting language based on the style of parametric variables.It is used to reduce a large amount of repetitive work in analysis(Gong and Xie 2004).This study carried out a simulation analysis of the temperature field considering nearly all conditions of construction, using the birth-death element and programming with APDL.3.1 Solving temperature field principle 3.1.1 Unsteady temperature field analysis The temperature of concrete changes during the construction period due to the effect of hydration heat of cement.This problem can be expressed as a heat conduction problem with internal heat sources in the area.The unsteady temperature field T(x, y, z,D)is written as(Zhu 1999): 公式1where □ is the thermal conductivity of concrete, c is the specific heat of concrete, □ is the density of concrete, □ is the adiabatic temperature rise of concrete, and □ is the age of concrete.In the 3D unsteady temperature field analysis, the functional form I e(T)is 公式2 where □R is a subfield of unit e;□0is the area on surface D , which is only in boundary units;c □ □ □□;□ is the exothermic coefficient;the thermal diffusivity c □ □ □ □;and isthe air temperature.a T3.1.2 Initial conditions and boundary conditions of concrete The initial conditions are the distribution laws of the initial transient temperature of internal concrete.The calculated initial temperature of concrete is 10 □.The index formula of hydration heat of cement is 公式 3 where t is the pouring time.The conversion between Q and □ is 公式4 The boundary conditions involve the laws of interaction between concrete and the surrounding medium.When concrete is exposed to the air, the boundary condition is 公式5 where n is the normal direction.Both and a T □ are constants or variables(Ashida and Tauchert 1998;Lin and Cheng 1997).During the maintenance period, the insulation materials of concrete are steel formworks and straws, and the exothermic coefficient of the outer surface is reduced as equivalent processing.The exothermic coefficients of the steel formwork and the straw are 45 kJ/(m2h+0)and 10 kJ/(m2h+0)，respectively.Based on the local temperature during construction, the following formula can be fitted according to the temperature variation curve: 公式63.2 Analysis of temperature field in ANSYS The simulation scheme of layered construction, which is based on the real construction scheme, is shown in T able 2.The pouring days in Table 2 are all the total days of construction for each layer.A layer is not poured until the former layer is poured.图表2The feature points are selected in every layer above the base plate.The maximum temperatures and the temperature curvesare given in Table 3 and Fig.5, respectively.Table 3 Coordinates and maximum temperature of feature points 图表3 图片5 Fig.5 Maximum temperature curves Fig.5 shows that the maximum temperature of each layer occurs on the 3rd or 4th day after pouring, and then the temperature decreases with time, which is consistent with related literature(Lin and Cheng 1997;Luna and Wu 2000;Wu and Luna 2001).In Fig.5, the numbers of feature points from 2 to 8 are corresponding to their maximum temperature curves from Nodetemp 2 to Nodetemp 8, and the curve of Nodetemp 9 is the air temperature curve.Feature point 8, the maximum temperature of which is 29.934 □ , occurrin g on the 206th day of the total construction period, shows the maximum temperature rise during the construction period.Feature point 4, the coordinates of which are(16.4, 16.0, 5.0), shows the maximum temperature difference of 23.5340.4 Analysis of thermal stress of intake tower Expansion or contraction of the structure occurs during heating and cooling.If the expansion or contraction of different parts is inconsistent, then thermal stress occurs.The indirect method was adopted in this study: the temperature of nodes was first obtained in analysis of the temperature field, and then applied to the structure as a body load.4.1 Selection of calculating parameters The parameters of concrete are given in Table 4.The elasticity modulus is 公式7 T able 4 Parameters of concrete 图表4 The creep effect must be considered in analysis of temperature stress.The creep degree of concrete is influenced by the cement type, water-cement ratio and admixture.The formula of the creep degree is 公式8 Considering the creep degree, the formula of the elasticity modulus is adjusted to be 公式94.2 Analysis of thermal stress in ANSYS As in analysis of thetemperature field, feature points were selected in each layer above the base plate, and their coordinates were the same as those in the temperature field analysis.The maximum thermal stress of each point is shown in Table 5.Feature point 9, the coordinates of which are(17.4, 10.8, 8.0), is the point with the maximum thermal stress.Table 5 Maximum thermal stress of feature points 图表5The thermal stress curves of feature points are shown in Fig.6.图片6Fig.6 Maximum stress curves In Fig.6, the numbers of feature points from 2 to 9 are corresponding to their maximum stress curves from S1_2 to S1_9, and the S1_10 curve is the ultimate tensile stress o f concrete.The formula of concrete’s ultimate tensile stress is 公式10 The figures and table show that the maximum thermal stress of the intake tower is 1.68 MPa, occurring on the 90th day of the construction period, which is the end of the third layer maintenance period and the beginning of the pouring of the fourth layer.It is known that the thermal stress increases with the temperature difference.Feature point 9 is located at the interface between the third layer and the fourth layer.Thus, it is postulated that the maximum thermal stress is caused by the instantaneous temperature difference between two layers in the pouring period.In Fig.6, the S1_10 curve shows the ultimate tensile stress curve of concrete.It is known that the maximum thermal stress of each point in the intake tower during the construction period is less than the ultimate tensile stress of concrete.5 Conclusions ⑴ The problem of the interface between SolidWorks and ANSYS is resolved in this study, realizing an effective combination of the advantages of both SolidWorks and ANSYS and providing a basis for analysis in ANSYS.(2)Using abirth-death element and considering layered construction, dynamic boundary conditions, hydration heat, the dynamic elasticity modulus, autogenous volume deformation and creep of concrete, the temperature field and thermal stress during the construction period are conveniently obtained due to the virtues of secondary development with APDL.(3)The analysis of temperature shows that the temperature of concrete rises rapidly in the early stage of construction, reaches a maximum value of 29.934 □ on the 3rd or 4th day after pouring, drops thereafter, and is consistent with air temperature after about 30 days.The thermal stress increases with the temperature difference, and the occurrence time of the maximum thermal stress is consistent with that of the maximum temperature difference.The maximum thermal stress occurs at the interface of new and old layers and is caused by the instantaneous temperature difference, the value of which is 1.68 MPa.(4)The maximum thermal stress is less than the ultimate tensile stress of concrete, which illustrates that the curing measures in construction are effective.Meanwhile, in view of the fact that the maximum thermal stress occurs at the interface of new and old layers, more attention should be paid to it, especially when there is a long interval of time between the pouring of different layers.References Ashida, F., and Tauchert, T.R.1998.An inverse problem for determination of transient surface temperature from piezoelectric sensor measurement.Journal of Applied Mechanics, 65(2), 367-373.[doi:10.1115/1.2789064] Barrett, P.R., Foadian, H., James, R.J., and Rashid, Y.R.1992.Thermal-structural analysis methods for RCC dams.Proceedings of the Conference of Roller Concrete III, 407-422.San Diego: ASCE.Gong, S.G., and Xie, mands and Parametric Programming inANSYS.Beijing: China Machine Press.(in Chinese)Kawaguchi, T., and Nakane, S.1996.Investigations on determining thermal stress in massive concrete structures.ACI Materials Journal, 93(1), 96-101.Lin, J.Y., and Cheng, T.F.1997.Numerical estimation of thermal conductivity from boundary temperature measurements.Numerical Heat Transfer, 32(2), 187-203.[doi:10.1080/***87] Liu, L.J., and Ren, J.P.2005.Application of the secondary development in SolidWorks.Mechanical Management and Development,(1), 74-75.(in Chinese)Luna, R., and Wu, Y.2000.Simulation of temperature and stress fields during RCC dam construction.Journal of Construction Engineering and Management, ASCE, 126(5), 381-388.[doi: 10.1061/(ASCE)0733-9364(2000)126:5(381)] Tatro, S.B.and Schrader, E.K.1985.Thermal consideration for roller compacted concrete.ACI Structural Journal, 82(2), 119-128.Wu, Y., and Luna, R.2001.Numerical implementation of temperature and creep in mass concrete.Finite Elements in Analysis and Design, 37(2), 97-106.[doi:10.1016/S0168-874X(00)00022-6] Zhang, J.2005.Interface design between AutoCAD and ANSYS.Chinese Quarterly of Mechanics, 26(2), 257-262.(in Chinese)Zhu, B.F.1999.Thermal Stresses and Temperature Control of Mass Concrete.Beijing: China Electric Power Press.(in Chinese)Zhu, B.F., and Xu, P.2001.Methods for stress analysis simulating the construction process of high concrete dams.Dam Engineering, 6(4), 243-260.Zhu, B.F.2006.Current situation and prospect of temperature control and cracking prevention technology for concrete dam.Journal of Hydraulic Engineering, 37(12), 1424-1432.(in Chinese)第二篇：英文文献翻译（模版）在回顾D和H的文章时，我愿意第一个去单独地讨论每一篇，然后发表一些总体的观点。
(完整版)机械类外文文献翻译
文献翻译英文原文：NOVEL METHOD OF REALIZING THE OPTIMAL TRANSMISSION OF THE CRANK-AND-ROCKER MECHANISM DESIGN Abstract: A novel method of realizing the optimal transmission of the crank-and-rocker mechanism is presented. The optimal combination design is made by finding the related optimal transmission parameters. The diagram of the optimal transmission is drawn. In the diagram, the relation among minimum transmission angle, the coefficient of travel speed variation, the oscillating angle of the rocker and the length of the bars is shown, concisely, conveniently and directly. The method possesses the main characteristic. That it is to achieve the optimal transmission parameters under the transmission angle by directly choosing in the diagram, according to the given requirements. The characteristics of the mechanical transmission can be improved to gain the optimal transmission effect by the method. Especially, the method is simple and convenient in practical use.Keywords：Crank-and-rocker mechanism, Optimal transmission angle, Coefficient of travel speed variationINTRODUCTIONBy conventional method of the crank-and-rocker design, it is very difficult to realize the optimal combination between the various parameters for optimal transmission. The figure-table design method introduced in this paper can help achieve this goal. With given conditions, we can, by only consulting the designing figures and tables, get the relations between every parameter and another of the designed crank-and-rocker mechanism. Thus the optimal transmission can be realized.The concerned designing theory and method, as well as the real cases of its application will be introduced later respectively.1ESTABLISHMENT OF DIAGRAM FOR OPTIMAL TRANSMISSION DESIGNIt is always one of the most important indexes that designers pursue to improve the efficiency and property of the transmission. The crank-and-rocker mechanism is widely used in the mechanical transmission. How to improve work ability and reduce unnecessary power losses is directly related to the coefficient of travel speed variation, the oscillating angle of the rocker and the ratio of the crank and rocker. The reasonable combination of these parameters takes an important effect on the efficiency and property of the mechanism, which mainly indicates in the evaluation of the minimum transmission angle.The aim realizing the optimal transmission of the mechanism is how to find themaximum of the minimum transmission angle. The design parameters are reasonably combined by the method of lessening constraints gradually and optimizing separately. Consequently, the complete constraint field realizing the optimal transmission is established.The following steps are taken in the usual design method. Firstly, the initial values of the length of rocker 3l and the oscillating angle of rocker ϕ are given. Then the value of the coefficient of travel speed variation K is chosen in the permitted range. Meanwhile, the coordinate of the fixed hinge of crank A possibly realized is calculated corresponding to value K .1.1 Length of bars of crank and rocker mechanismAs shown in Fig.1, left arc G C 2 is the permitted field of point A . Thecoordinates of point A are chosen by small step from point 2C to point G .The coordinates of point A are 02h y y c A -= (1)22A A y R x -= (2)where 0h , the step, is increased by small increment within range(0,H ). If the smaller the chosen step is, the higher the computational precision will be. R is the radius of the design circle. d is the distance from 2C to G .2cos )2cos(22cos 33ϕθϕϕ⎥⎦⎤⎢⎣⎡--+=l R l d (3) Calculating the length of arc 1AC and 2AC , the length of the bars of themechanism corresponding to point A is obtained [1,2].1.2 Minimum transmission angle min γMinimum transmission angle min γ(see Fig.2) is determined by the equations [3]322142322min 2)(cos l l l l l l --+=γ (4) 322142322max 2)(cos l l l l l l +-+=γ (5) max min180γγ-︒=' (6) where 1l ——Length of crank(mm)2l ——Length of connecting bar(mm)3l ——Length of rocker(mm)4l ——Length of machine frame(mm)Firstly, we choose minimum comparing min γ with minγ'. And then we record all values of min γ greater than or equal to ︒40 and choose the maximum of them.Secondly, we find the maximum of min γ corresponding to any oscillating angle ϕ which is chosen by small step in the permitted range (maximum of min γ is different oscillating angle ϕ and the coefficient of travel speed variation K ).Finally, we change the length of rockerl by small step similarly. Thus we3γcorresponding to the different length of bars, may obtain the maximum ofmindifferent oscillating angle ϕand the coefficient of travel speed variation K.Fig.3 is accomplished from Table for the purpose of diagram design.It is worth pointing out that whatever the length of rocker 3l is evaluated, the location that the maximum of min γ arises is only related to the ratio of the length of rocker and the length of machine frame 3l /4l , while independent of 3l .2 DESIGN METHOD2.1 Realizing the optimal transmission design given the coefficient of travelspeed variation and the maximum oscillating angle of the rockerThe design procedure is as follows.(1) According to given K and ϕ, taken account to the formula the extreme included angle θ is found. The corresponding ratio of the length of bars 3l /4l is obtained consulting Fig.3.︒⨯+-=18011K K θ (7) (2) Choose the length of rocker 3l according to the work requirement, the length of the machine frame is obtained from the ratio 3l /4l .(3) Choose the centre of fixed hinge D as the vertex arbitrarily, and plot an isosceles triangle, the side of which is equal to the length of rocker 3l (see Fig.4), andϕ=∠21DC C . Then plot 212C C M C ⊥, draw N C 1, and make angleθ-︒=∠9012N C C . Thus the point of intersection of M C 2 and N C 1 is gained. Finally, draw the circumcircle of triangle 21C PC ∆.(4) Plot an arc with point D as the centre of the circle, 4l as the radius. The arc intersections arc G C 2 at point A . Point A is just the centre of the fixed hinge of the crank.Therefore, from the length of the crank2/)(211AC AC l -= (8)and the length of the connecting bar112l AC l -= (9)we will obtain the crank and rocker mechanism consisted of 1l , 2l , 3l , and 4l .Thus the optimal transmission property is realized under given conditions.2.2 Realizing the optimal transmission design given the length of the rocker (or the length of the machine frame) and the coefficient of travel speed variationWe take the following steps.(1) The appropriate ratio of the bars 3l /4l can be chosen according to given K . Furthermore, we find the length of machine frame 4l (the length of rocker 3l ).(2) The corresponding oscillating angle of the rocker can be obtained consulting Fig.3. And we calculate the extreme included angle θ.Then repeat (3) and (4) in section 2.13 DESIGN EXAMPLEThe known conditions are that the coefficient of travel speed variation1818.1=K and maximum oscillating angle ︒=40ϕ. The crankandrockermechanism realizing the optimal transmission is designed by the diagram solution method presented above.First, with Eq.(7), we can calculate the extreme included angle ︒=15θ. Then, we find 93.0/43=l l consulting Fig.3 according to the values of θ and ϕ.If evaluate 503=l mm, then we will obtain 76.5393.0/504==l mm. Next, draw sketch(omitted).As result, the length of bars is 161=l mm,462=l mm,503=l mm,76.534=l mm.The minimum transmission angle is︒=--+=3698.462)(arccos 322142322min l l l l l l γ The results obtained by computer are 2227.161=l mm, 5093.442=l mm, 0000.503=l mm, 8986.534=l mm.Provided that the figure design is carried under the condition of the Auto CAD circumstances, very precise design results can be achieved.4 CONCLUSIONSA novel approach of diagram solution can realize the optimal transmission of the crank-and-rocker mechanism. The method is simple and convenient in the practical use. In conventional design of mechanism, taking 0.1 mm as the value of effective the precision of the component sizes will be enough.译文：认识曲柄摇臂机构设计的最优传动方法摘要：一种曲柄摇臂机构设计的最优传动的方法被提出。
机械类外文文献
附：外文翻译外文原文：Fundamentals of Mechanical Design Mechanical design means the design of things and systems of a mechanical nature—machines, products, structures, devices, and instruments. For the most part mechanical design utilizes mathematics, the materials sciences, and the engineering-mechanics sciences.The total design process is of interest to us. How does it begin? Does the engineer simply sit down at his desk with a blank sheet of paper? And, as he jots down some ideas, what happens next? What factors influence or control the decisions which have to be made? Finally, then, how does this design process end?Sometimes, but not always, design begins when an engineer recognizes a need and decides to do something about it. Recognition of the need and phrasing it in so many words often constitute a highly creative act because the need may be only a vague discontent, a feeling of uneasiness, of a sensing that something is not right.The need is usually not evident at all. For example, the need to do something about a food-packaging machine may be indicated by the noise level, by the variations in package weight, and by slight but perceptible variations in the quality of the packaging or wrap.There is a distinct difference between the statement of the need and the identification of the problem. Which follows this statement? The problem is more specific. If the need is for cleaner air, the problem might be that of reducing the dust discharge from power-plant stacks, or reducing the quantity of irritants from automotive exhausts.Definition of the problem must include all the specifications for the thing that is to be designed. The specifications are the input and output quantities, the characteristics of the space the thing must occupy and all the limitations on these quantities. We can regard the thing to be designed as something in a black box. In this case we must specify the inputs and outputs of the box together with their characteristics and limitations. The specifications define the cost, the number to be manufactured, the expected life, the range, the operating temperature, and the reliability.There are many implied specifications which result either from the designer's particular environment or from the nature of the problem itself. The manufacturing processes which are available, together with the facilities of a certain plant, constitute restrictions on a designer's freedom, and hence are a part of the implied specifications. A small plant, for instance, may not own cold-working machinery. Knowing this, the designer selects other metal-processing methods which can be performed in the plant. The labor skills available and the competitive situation also constitute implied specifications.After the problem has been defined and a set of written and implied specifications has been obtained, the next step in design is the synthesis of an optimum solution. Now synthesis cannot take place without both analysis and optimization because the system under design must be analyzed to determine whether theperformance complies with the specifications.The design is an iterative process in which we proceed through several steps, evaluate the results, and then return to an earlier phase of the procedure. Thus we may synthesize several components of a system, analyze and optimize them, and return to synthesis to see what effect this has on the remaining parts of the system. Both analysis and optimization require that we construct or devise abstract models of the system which will admit some form of mathematical analysis. We call these models mathematical models. In creating them it is our hope that we can find one which will simulate the real physical system very well.Evaluation is a significant phase of the total design process. Evaluation is the final proof of a successful design, which usually involves the testing of a prototype in the laboratory. Here we wish to discover if the design really satisfies the need or needs. Is it reliable? Will it compete successfully with similar products? Is it economical to manufacture and to use? Is it easily maintained and adjusted? Can a profit be made from its sale or use?Communicating the design to others is the final, vital step in the design process. Undoubtedly many great designs, inventions, and creative works have been lost to mankind simply because the originators were unable or unwilling to explain their accomplishments to others. Presentation is a selling job. The engineer, when presenting a new solution to administrative, management, or supervisory persons, is attempting to sell or to prove to them that this solution is a better one. Unless this can be done successfully, the time and effort spent on obtaining the solution have been largely wasted.Basically, there are only three means of communication available to us. There are the written, the oral, and the graphical forms. Therefore the successful engineer will be technically competent and versatile in all three forms of communication. A technically competent person who lacks ability in any one of these forms is severely handicapped. If ability in all three forms is lacking, no one will ever know how competent that person is!The competent engineer should not be afraid of the possibility of not succeeding in a presentation. In fact, occasional failure should be expected because failure or criticism seems to accompany every really creative idea. There is a great to be learned from a failure, and the greatest gains are obtained by those willing to risk defeat. In the find analysis, the real failure would lie in deciding not to make the presentation at all.Introduction to Machine DesignMachine design is the application of science and technology to devise new or improved products for the purpose of satisfying human needs. It is a vast field of engineering technology which not only concerns itself with the original conception of the product in terms of its size, shape and construction details, but also considers the various factors involved in the manufacture, marketing and use of the product.People who perform the various functions of machine design are typically called designers, or design engineers. Machine design is basically a creative activity. However, in addition to being innovative, a designengineer must also have a solid background in the areas of mechanical drawing, kinematics, dynamics, materials engineering, strength of materials and manufacturing processes.As stated previously, the purpose of machine design is to produce a product which will serve a need for man. Inventions, discoveries and scientific knowledge by themselves do not necessarily benefit people; only if they are incorporated into a designed product will a benefit be derived. It should be recognized, therefore, that a human need must be identified before a particular product is designed.Machine design should be considered to be an opportunity to use innovative talents to envision a design of a product is to be manufactured. It is important to understand the fundamentals of engineering rather than memorize mere facts and equations. There are no facts or equations which alone can be used to provide all the correct decisions to produce a good design. On the other hand, any calculations made must be done with the utmost care and precision. For example, if a decimal point is misplaced, an otherwise acceptable design may not function.Good designs require trying new ideas and being willing to take a certain amount of risk, knowing that is the new idea does not work the existing method can be reinstated. Thus a designer must have patience, since there is no assurance of success for the time and effort expended. Creating a completely new design generally requires that many old and well-established methods be thrust aside. This is not easy since many people cling to familiar ideas, techniques and attitudes. A design engineer should constantly search for ways to improve an existing product and must decide what old, proven concepts should be used and what new, untried ideas should be incorporated.New designs generally have “bugs” or unforeseen problems which must be worked out before the superior characteristics of the new designs can be enjoyed. Thus there is a chance for a superior product, but only at higher risk. It should be emphasized that if a design does not warrant radical new methods, such methods should not be applied merely for the sake of change.During the beginning stages of design, creativity should be allowed to flourish without a great number of constraints. Even though many impractical ideas may arise, it is usually easy to eliminate them in the early stages of design before firm details are required by manufacturing. In this way, innovative ideas are not inhibited. Quite often, more than one design is developed, up to the point where they can be compared against each other. It is entirely possible that the design which ultimately accepted will use ideas existing in one of the rejected designs that did not show as much overall promise.Psychologists frequently talk about trying to fit people to the machines they operate. It is essentially the responsibility of the design engineer to strive to fit machines to people. This is not an easy task, since there is really no average person for which certain operating dimensions and procedures are optimum.Another important point which should be recognized is that a design engineer must be able to communicate ideas to other people if they are to be incorporated. Initially the designer must communicate a preliminary design to get management approval. This is usually done by verbal discussions in conjunction with drawinglayouts and written material. To communicate effectively, the following questions must be answered:(1)Does the design really serve a human need?(2)Will it be competitive with existing products of rival companies?(3)Is it economical to produce?(4)Can it be readily maintained?(5)Will it sell and make a profit?Only time will provide the true answers to the preceding questions, but the product should be designed, manufactured and marketed only with initial affirmative answers. The design engineer also must communicate the finalized design to manufacturing through the use of detail and assembly drawings.Quite often, a problem well occur during the manufacturing cycle. It may be that a change is required in the dimensioning or telegramming of a part so that it can be more readily produced. This falls in the category of engineering changes which must be approved by the design engineer so that the product function will not be adversely affected. In other cases, a deficiency in the design may appear during assembly or testing just prior to shipping. These realities simply bear out the fact that design is a living process. There is always a better way to do it and the designer should constantly strive towards finding that better way.MachiningTurning The engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in today's production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish and accuracy, are now at the designer's fingertips with production speeds on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret Lathes Production machining equipment must be evaluated now, more than ever before, in terms of ability to repeat accurately and rapidly. Applying this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turret lathe, the designer should strive for a minimum of operations.Automatic Screw Machines Generally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle automatics and automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the automatic screw machine has long since exceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic to set up on the turret lathe than on the automatic screw machine. Quantities less than 1000 parts may be more economical to set up on the turret lathe than on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer Lathes Since surface roughness depends greatly upon material turned, tooling, and fees and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.Is some case, tolerances of ±0.05mm are held in continuous production using but one cut. Groove width can be held to ±0.125mm on some parts. Bores and single-point finishes can be held to ±0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of ±0.125mm is economical on both diameter and length of turn.Milling With the exceptions of turning and drilling, milling is undoubtedly the most widely used method of removing metal. Well suited and readily adapted to the economical production of any quantity of parts, the almost unlimited versatility of the milling process merits the attention and consideration of designers seriously concerned with the manufacture of their product.As in any other process, parts that have to be milled should be designed with economical tolerances that can be achieved in production milling. If the part is designed with tolerances finer than necessary, additional operations will have to be added to achieve these tolerances——and this will increase the cost of the part.Grinding is one of the most widely used methods of finishing parts to extremely close tolerances and low surface roughness. Currently, there are grinders for almost for almost every type of grinding operation. Particular design features of a part dictate to a large degree the type of grinding machine required. Where processing costs are excessive, parts redesigned to utilize a less expensive, higher output grinding method may be well worthwhile. For example, wherever possible the production economy of center less grinding should be taken advantage of by proper design consideration.Although grinding is usually considered a finishing operation, it is often employed as a complete machining process on work which can be ground down from rough condition without being turned or otherwise machined. Thus many types of forgings and other parts are finished completely with the grinding wheel at appreciable savings of time and expense.Classes of grinding machines include the following: cylindrical grinders, center less grinders, internal grinders, surface grinders, and tool and cutter grinders.The cylindrical and center less grinders are for straight cylindrical or taper work; thus splices, shafts, and similar parts are ground on cylindrical machines either of the common-center type or the center less machine.Thread grinders are used for grinding precision threads for thread gages, and threads on precision parts where the concentricity between the diameter of the shaft and the pitch diameter of the thread must be held to close tolerances.The internal grinders are used for grinding of precision holes, cylinder bores, and similar operations where bores of all kinds are to be finished.The surface grinders are for finishing all kinds of flat work, or work with plain surfaces which may be operated upon either by the edge of a wheel or by the face of a grinding wheel. These machines may have reciprocating or rotating tables.译文：机械设计基础机械设计基础是指机械装置和机械系统——机器、产品、结构、设备和仪器的设计。
机械专业毕业设计外文翻译相关外文文献
Fraunhofer-IBMT Technology Center Hialeah, 601 West 20 th Street, Hialeah, FL 33010, USA b TRS Ceramics, Inc, 2820 E. College Avenue, Suite J, State College, PA 16801, USA Received 28 January 2002; accepted 24 March 2002
* Corresponding author. Tel.: 1 1-305-925-1260; fax: 1 1-305-925-1269. E-mail addresses: epark@ (S.-E.E. Park), info@ (W. Hackenberger). 1359-0286 / 02 / $ – see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S1359-0286( 02 )00023-2
Fig. 1. Comparison of E-field induced strains for relaxor-PT single crystals versus various types of electroactive ceramics, (a) non-hysteretic strain behavior at E-fields before the E-field induced phase transition, and (b) strain behaviors associated with the E-field induced phase transition.
Current Opinion in Solid State and Materials Science 6 (2002) 11–18
机械设计制造及其自动化参考文献英文
机械设计制造及其自动化参考文献英文1. Hahn, R.S., 2010. Introduction to mechanical engineering design and manufacturing. CRC Press.2. Zhang, J., Liu, X., Fang, Y. and Xu, D., 2016. A collaborative optimization approach for product design and manufacturing process planning. Journal of Intelligent Manufacturing, 27(4), pp.803-819.3. Yang, S., Guo, D., Cai, W., Li, Z. and Zhou, H., 2017. Research on the application of cloud manufacturing in mechanical design and manufacturing. International Journal of Advanced Manufacturing Technology, 92(9-12), pp.3639-3648.4. Rao, P.N. and Chidambara, M.R., 2015. Design for manufacturing and assembly-a review. International Journal of Engineering Research and Applications, 5(8), pp.84-90.5. Hu, Q., Chen, S. and Su, Y., 2014. Design for manufacturability: A literature review. Journal of Industrial Integration and Management, 2(3), p.145.6. Ulrich, K.T. and Eppinger, S.D., 2017. Product design and development. McGraw-Hill Education.7. Wang, Z., Li, B., Zhao, J. and Wu, G., 2018. Design for additive manufacturing: A review of requirements and challenges. International Journal of Advanced ManufacturingTechnology, 94(9-12), pp.3563-3577.8. Kim, D. and Cho, D.W., 2015. Review of manufacturing technologies for tissue engineering applications. Procedia Engineering, 110, pp.139-144.9. Kuo, R.J., Ho, L.C. and Lu, Y.Y., 2016. An innovative manufacturing system for smart production of customized eyeglasses. Journal of Intelligent Manufacturing, 27(4), pp.821-836.10. Wang, G., Zou, Y., Li, W. and Xu, X., 2017. A review of research on modeling and optimization of machining processes. International Journal of Machine Tools and Manufacture, 122, pp.1-17.。
机械设计英文文献(带翻译)
英语文献翻译Introduction of MachiningHave a shape as a processing method, all machining process for the production of the most commonly used and most important method. Machining process is a process generated shape, in this process, Drivers device on the work piece material to be in the form of chip removal. Although in some occasions, the workpiece under no circumstances, the use of mobile equipment to the processing, However, the majority of the machining is not only supporting the workpiece also supporting tools and equipment to complete.Machining know the process has two aspects. Small group of low-cost production. For casting, forging and machining pressure, every production of a specific shape of the workpiece, even a spare parts, almost have to spend the high cost of processing. Welding to rely on the shape of the structure, to a large extent, depend on effective in the form of raw materials. In general, through the use of expensive equipment and without special processing conditions, can be almost any type of raw materials, mechanical processing to convert the raw materials processed into the arbitrary shape of the structure, as long as the external dimensions large enough, it is possible. Because of a production of spare parts, even when the parts and structure of the production batch sizes aresuitable for the original casting, Forging or pressure processing to produce, but usually prefer machining.Strict precision and good surface finish, machining the second purpose is the establishment of the high precision and surface finish possible on the basis of. Many parts, if any other means of production belonging to the large-scale production, Well Machining is a low-tolerance and can meet the requirements of small batch production. Besides, many parts on the production and processing of coarse process to improve its general shape of the surface. It is only necessary precision and choose only the surface machining. For instance, thread, in addition to mechanical processing, almost no other processing method for processing. Another example is the blacksmith pieces keyhole processing, as well as training to be conducted immediately after the mechanical completion of the processing.Primary Cutting ParametersCutting the work piece and tool based on the basic relationship between the following four elements to fully describe : the tool geometry, cutting speed, feed rate, depth and penetration of a cutting tool.Cutting Tools must be of a suitable material to manufacture, it must be strong, tough, hard and wear-resistant. Tool geometry -- to the tip plane and cutter angle characteristics -- for each cutting process must be correct.Cutting speed is the cutting edge of work piece surface rate, it is inches per minute to show. In order to effectively processing, and cutting speed must adapt to the level of specific parts -- with knives. Generally, the more hard work piece material, the lower the rate.Progressive Tool to speed is cut into the work piece speed. If the work piece or tool for rotating movement, feed rate per round over the number of inches to the measurement. When the work piece or tool for reciprocating movement and feed rate on each trip through the measurement of inches. Generally, in other conditions, feed rate and cutting speed is inversely proportional to.Depth of penetration of a cutting tool -- to inches dollars -- is the tool to the work piece distance. Rotary cutting it to the chip or equal to the width of the linear cutting chip thickness. Rough than finishing, deeper penetration of a cutting tool depth.Rough machining and finishing machiningThere are two kinds of cuts in machine- shop work called, respectively, the "roughing cut" and the "finishing cut". When a piece is "roughed out", it is quite near the shape and size required, but enough metal has been left on the surface to finish smooth and to exact size." Generally speaking, bars of steel, forging, castings, etc. are machined to the required shape and size with only one roughing and one finishing cut. Sometimes, however, certain portions of a piece may require more thanone roughing cut. Also, in some jobs, for example, when great accuracy is not needed, or when a comparatively small amount of metal must be removed, a finishing cut may be all that is required. The roughing cut, to remove the greater part of the excess material, should be reasonably heavy, that is, all the machine, or cutting tool, or work, or all three, will stand. So the machinist’s purpose is to remove the excess stock as fast as he can without leaving, at the same time, a surface too torn and rough, without bending the piece if it is slender, and without spoiling the centers. The finishing cut, to make the work smooth and accurate, is a finer cut. The emphasis here is refinement - very sharp tool, comparatively little metal removed, and a higher degree of accuracy in measurement. Whether roughing or finishing, the machinist must set the machine for the given job. He must consider the size and shape of the work and the kind of material, also the kind of tool used and the nature of the cut to be made, then he proceeds to set the machine for the correct speed and feed and to set the tool to take the depth of cut desired.Automatic Fixture DesignAssembly equipment used in the traditional synchronous fixture put parts of the fixture mobile center, to ensure that components from transmission from the plane or equipment plate placed after removal has been scheduled for position. However, in certain applications, mobile mandatory parts of the center line, it may cause parts or equipmentdamage. When parts vulnerability and may lead to a small vibration abandoned, or when their location is by machine spindle or specific to die, Tolerance again or when the request is a sophisticated, it would rather let the fixture to adapt to the location of parts, and not the contrary. For these tasks, Elyria, Ohio, the company has developed Zaytran a general non-functional data synchronization West category FLEXIBILITY fixture. Fixture because of the interaction and synchronization devices is independent; the synchronous device can use sophisticated equipment to replace the slip without affecting the fixture force. Fixture specification range from 0.2 inches itinerary, 5 pounds clamping force of the six-inch trip, 400-inch clamping force. The characteristics of modern production are becoming smaller and smaller quantities and product specifications biggest changes. Therefore, in the final stages of production, assembly of production, quantity and product design changes appear to be particularly vulnerable. This situation is forcing many companies to make greater efforts to rationalize the extensive reform and the previously mentioned case of assembly automation. Despite flexible fixture behind the rapid development of flexible transport and handling devices, such as backward in the development of industrial robots, it is still expected to increase the flexibility fixture. In fact the important fixture devices -- the production of the devices to strengthen investment on the fixture so that more flexibility in economic support holders.According to their flexibility and fixture can be divided into: special fixture, the fixture combinations, the standard fixture, high flexible fixture. Flexible fixture on different parts of their high adaptability and the few low-cost replacement for the characteristic.Forms can transform the structure of the flexible fixture can be installed with the change of structure components (such as needle cheek plate, Multi-chip components and flake cheek plate), a non-standard work piece gripper or clamping elements (for example: commencement standard with a clamping fixture and mobile components fixture supporting documents), or with ceramic or hardening of the intermediary substances (such as : Mobile particle bed fixture and heat fixture tight fixture). To production, the parts were secured fixture, the need to generate clamping function, its fixture with a few unrelated to the sexual submissive steps.According to the processing was part of that foundation and working characteristics to determine the work piece fixture in the required position, then need to select some stability flat combination, These constitute a stable plane was fixed in the work piece fixture set position on the clamp-profile structure, all balanced and torque, it has also ensured that the work features close to the work piece. Finally, it must be calculated and adjusted, assembly or disassembly be standard fixture components required for the position, so that the work piece firmly by clampingfixture in China. In accordance with this procedure, the outline fixture structure and equipped with the planning and recording process can be automated control.Structural modeling task is to produce some stable flat combination, Thus, these plane of the work pieces clamping force and will fixture stability. According to usual practice, this task can be human-machine dialogue that is almost completely automated way to completion. A man-machine dialogue that is automated fixture structure modeling to determine the merits can be conducted in an organized and planning fixture design reduce the amount of the design, shortening the study period and better distribution of work conditions. In short, can be successfully achieved significantly improve fixture efficiency and effectiveness.Fully prepared to structure programs and the number of material circumstances, the completion of the first successful assembly can save up to 60% of the time.Therefore fixture process modeling agencies is the purpose of the program has appropriate documents.机械加工机械加工是所有制造过程中最普遍使用的而且是最重要的方法。
机械设计外文文献
Mechanical DesignJohn ErnstAbstract：A machine is a combination of mechanisms and other components which transforms transmits. Examples are engines, turbines, vehicles, hoists, printing presses, washing machines, and movie cameras. Many of the principles and methods of design that apply to machines also apply to manufactured articles that are not true machines. The term "mechanical design" is used in a broader sense than "machine design" to include their design. The motion and structural aspects and the provisions for retention and enclosure are considerations in mechanical design. Applications occur in the field of mechanical engineering, and in other engineering fields as well, all of which require mechanical devices, such as switches, cams, valves, vessels, and mixers.Keywords: Mechanical Design；Mechanisms Design Process；Application1. The Design ProgressDesigning starts with a need real. Existing apparatus may need improvements in durability, efficiency, weight, speed, or cost. New apparatus may be needed to perform a function previously Done by men, such as computation, assembly, or servicing. With the objective wholly or partlyIn the design preliminary stage, should allow to design the personnel fully to display the creativity, not each kind of restraint. Even if has had many impractical ideas, also can in the design early time, namely in front of the plan blueprint is corrected. Only then, only then does not send to stops up the innovation the mentality. Usually, must propose several sets of design proposals, and then perform the comparison. Has the possibility very much in the plan which finally designated, has used certain not in plan some ideas which accepts.When the general shape and a few dimensions of the several components become apparent, analysis can begin in earnest. The analysis will have as its objective satisfactory or superiorperformance, plus safety and durability with minimum weight, and a competitive cost. Optimum proportions and dimensions will be sought for each critically loaded section, together with a balance between the strengths of the several components. Materials and their treatment will be chosen. These important objectives can be attained only by analysis based upon the principles of mechanics, such as those of static for reaction forces and for the optimum utilization of friction; of dynamics for inertia, acceleration, and energy; of elasticity and strength of materials for stress and deflection; of physical behavior of materials; and of fluid mechanics for lubrication and hydrodynamic drives. The analyses may be made by the same engineer who conceived the arrangement of mechanisms, or, in a large company, they may be made by a separate analysis division or research group. Design is a reiterative and cooperative process, whether done formally or informally, and the analyst can contribute to phases other than his own. Product design requires much research and development. Many Concepts of an idea must be studied, tried, and then either used or discarded. Although the content of each engineering problem is unique, the designers follow the similar process to solve the problems.Product liability suits designers and forced in material selection, using the best program. In the process of material, the most common problems for five (a) don't understand or not use about the latest application materials to the best information, (b) failed to foresee and consider the reasonable use material may (such as possible, designers should further forecast and consider due to improper use products. In recent years, many products liability in litigation, the use of products and hurt the plaintiff accused manufacturer, and won the decision), (c) of the materials used all or some of the data, data, especially when the uncertainty long-term performance data is so, (d) quality control method is not suitable and unproven, (e) by some completely incompetent persons choose materials.Through to the above five questions analysis, may obtain thesequestions is does not have the sufficient reason existence the conclusion. May for avoid these questions to these questions research analyses the appearance indicating the direction. Although uses the best choice of material method not to be able to avoid having the product responsibility lawsuit, designs the personnel and the industry carries on the choice of material according to the suitable procedure, may greatly reduce the lawsuit the quantity.May see from the above discussion, the choice material people should to the material nature, the characteristic and the processing method have comprehensive and the basic understanding.Finally, a design based upon function, and a prototype may be built. If its tests are satisfactory, the initial design will undergo certain modifications that enable it to be manufactured in quantity at a lower cost. During subsequent years of manufacture and service, the design is likely to undergo changes as new ideas are conceived or as further analyses based upon tests and experience indicate alterations. Sales appeal.2. Some Rules for DesignIn this section it is suggested that, applied with a creative attitude, analyses can lead to important improvements and to the conception and perfection of alternate, perhaps more functional, economical, and durable products.To stimulate creative thought, the following rules are suggested for the designer and analyst. The first six rules are particularly applicable for the analyst.（1）A creative use of need of physical properties and control process.(2）Recognize functional loads and their significance.(3) Anticipate unintentional loads.(4) Devise more favorable loading conditions.(5) Provide for favorable stress distribution and stiffness with minimum weight.(6) Use basic equations to proportion and optimize dimensions.（7）Choose materials for a combination of properties.（8）Select carefully, stock and integral components.（9）Modify a functional design to fit the manufacturing process and reduce cost.（10）Provide for accurate location and noninterference of parts in assembly.Machinery design covers the following contents.(1).Provides an introduction to the design process, problem formulation, and safety factors.(2).Reviews the material properties and static and dynamic loading analysis, Including beam, vibration and impact loading.(3) Reviews the fundamentals of stress and defection analysis.(4)Introduces fatigue-failure theory with the emphasis on stress-life approaches to high-cycle fatigue design, which is commonly used in the design of rotation machinery.(5) Discusses thoroughly the phenomena of wear mechanisms, surface contact stresses, and surface fatigue.(6) Investigates shaft design using the fatigue-analysis techniques.(7) Discusses fluid-film and rolling-element bearing theory and application(8) Gives a thorough introduction to the kinematics, design and stress analysis of spur gears, and a simple introduction to helical, bevel, and worm gearing.(9) Discusses spring design including compression, extension and torsion springs.(10) Deals with screws and fasteners including power screw and preload fasteners.(11) Introduces the design and specification of disk and drum clutches and brakes.The complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineering material, materials mechanics and machine manufacture technology has the deepelementary knowledge.One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations.Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked.The computer is a tool helpful to mechanical designers to lighten tedious calculations, and provide extended analysis of available data. Interactive systems, based on computer capabilities, have made possible the concepts of computer aided design (CAD) and computer-aided manufacturing (CAM). How does the psychologist frequently discuss causes the machine which the people adapts them to operate. A design personnel’s basic responsibility is diligently causes the machine to adapt the people. This certainly is not an easy work, because certainly does not have to all people to say in fact all is the most superior operating area and the operating process. Another important question, project engineer must be able to carry on the exchange and the consultation with other concerned personnel. In the initial stage, designs the personnel to have to carry on the exchange and the consultation on the preliminary design with the administrative personnel, and is approved. This generally is through the oral discussion, the schematic diagram and the writing material carries on.If front sues, the machine design goal is the production can meet the human need the product. The invention, the discovery and technical knowledge itself certainly not necessarily can bring theadvantage to the humanity, only has when they are applied can produce on the product the benefit. Thus, should realize to carries on before the design in a specific product, must first determine whether the people do need this kind of productMust regard as the machine design is the machine design personnel carries on using creative ability the product design, the system analysis and a formulation product manufacture technology good opportunity. Grasps the project elementary knowledge to have to memorize some data and the formula is more important than. The merely service data and the formula is insufficient to the completely decision which makes in a good design needs. On the other hand, should be earnest precisely carries on all operations. For example, even if places wrong a decimal point position, also can cause the correct design to turn wrongly.Good design personnel should dare to propose the new idea moreover is willing to undertake the certain risk, when the new method is not suitable, use original method. Therefore, designs the personnel to have to have to have the patience, because spends the time and the endeavor certainly cannot guarantee brings successfully. A brand-new design, the request screen abandons absolutely many, knows very well the method for the people. Because many person of conservativeness does this certainly is not an easy matter. A mechanical designer should unceasingly explore the improvement existing product the method, should earnestly choose originally, the process confirmation principle of design in this process, with has not unified it after the confirmation new idea.Human life can not be separated from the machinery, it is everywhere, but for the mechanical manufacturing, production, and its development and future, we know little about. After this semester, I have more knowledge and understanding of the profession of the mechanical.From the primitive society of early human use such as axes, knives and other simple tools, to a simple lever, pulley, human bicycles, animal-Kip Shum car tools, developed to a more complexhydraulic drive, wind-driven Shuinian and windmills morecomplex machinery. After the 18th century British Industrial Revolution, the steam engine, internal combustion engines, electric motors, mechanical power source for the rapid development of manufacturing, transport, human beings began to enter the modern civilized society. The 20th century, the computer issuing automatic control technology, information technology, infectious organic combination of technology, so that the machinery is fully modernized phase. Robotics, CNC machine tools, high-speed delivery vehicles, heavy machinery and the large number of advanced machinery and equipment to accelerate the prosperity and progress of human society, humans can travel into space, landing on the moon, you can explore the vast depths of the sea, to live and pass below the surface all of which can not be separated from the machinery, the development of the machinery into the intelligent stage. Machinery has become one of the five elements of production and services of modern society. The history of the development of the mechanical history of the development of human civilization.In ancient Chinese mechanical engineering, invention and creativity is very brilliant, such as grinding technology, metal smelting technology. China's machinery manufacturing industry developed after 1949. After the founding of new China, the tremendous achievements of China’s economy are inseparable from the progress of the manufacturing sector. After decades of struggle, China's manufacturing components with considerable scale and level of manufacturing systems, today China have become a remarkable manufacturing country. Machinery manufacturing industry overall scale of production is constantly increasing, machinery manufacturing is more than 100 industry, 8.57 million enterprises (large enterprises accounted for 1%) and 60,000 kinds of products a complete range of industrial system. For six consecutive years in China's largest export commodity status, the machinery industry production capacity is 2600 times that of the liberation of the world 5, the machine has a world, vehicle production in the world 4.But we still need to clearly recognize that China is a big manufacturing country, far from being a manufacturing powerhouse. The overall size of the added value of product technology and per capita labor efficiency is far better than the United States, Japan and other manufacturing power. Therefore, the task of development of China's manufacturing industry a long way to go. With the diversification of the high-tech development and social needs of the industrial production rapidly toward large-scale, integrated and complex, so that the modern industrial machinery industry is facing new opportunities and challenges, and more emphasis on the creativity and the efficiency of the workers. Therefore need to continuously enhance the level of China's Mechanical Design Manufacturing and Automation, thereby contributing to the development of China's machinery manufacturing industry.。
机械设计英文参考文献
MOLD MATERIALS MAKING THE MOST OF HIGH—PERFORMANCEMOLD MATERIALSUnderstanding high conductivity alloys and optimizing their use can help you build better molds.By Douglas Veitch, Director, Brush WellmanInjection molders and blow molders can benefit from high conductivity alloys by achieving faster cycle times and better part quality. There are certain properties of the mold material and polymer that enable these efficiencies to be realized. Once these characteristics are understood, mold builders can optimize their use of high-performance materials to provide a durable, fast-cycling mold for their customers.Cooling TimeMold Alloy Thermal PropertiesSome characteristics of mold materials enable us to better understand the thermal process that occurs while molding. Three important properties are:1. Thermal ConductivityHigher thermal conductivity equates to the transfer of more thermal energy per unit of time under steady state conditions.2. Thermal DiffusivityHigher thermal diffusivity means that thermal equilibrium will be reached faster when the temperature changes. A good thermal diffuser will react more quickly to environmental temperature changes.3. Thermal Effusivity (conductivity divided by the square root of the diffusivity)Higher thermal effusivity is a measure of the material’s efficiency at instantly removing heat from an object at a higher temperature with which it suddenly makes contact (see Chart 1).The following explains what all of this means when molding plastics.1. Heat mold up to operating temperature (via water channels).•The higher diffusivity allows the copper mold alloy to reach equilibrium faster, so the molding operation can begin sooner.2. Inject hot plastic melt into the mold and cool.•Higher effusivity means the mold will begin to instantly and efficiently remove heat from the plastic.•Then the high diffusivity translates to reaching steady state, uniform temperature quickly.•Finally, once at equilibrium the conductivity determines how fast the thermal energy will be removed from the plastic until the part reaches the desired ejection temperature.3. Maintain setpoint temperature (equal to water temperature) during mold-open, ejection and mold-close portions of the cycle.•Again, the high diffusivity enables the mold to maintain equilibrium at setpoint during mold open, ejection and mold close. Since the air is a poor thermal medium, the contact between the water and copper is the overriding factor.Figure 1: IR temp distribution. Images courtesy of Brush Wellman Inc.Figure 1 shows pictures from a thermal FEA illustrating the uniform temperature of a copper beryllium mold compared to that of a mold made of P-20 steel.Polymer TypesThe two main polymer families—semi-crystalline and amorphous—both benefit from higher conductivity mold materials.Semi-crystalline polymers have a densely packed, uniform molecular structure and include materials such as polyamide (nylon), polyethylene, polypropylene and polyacetal. These polymers become amorphous when melted during processing and will become semi-crystalline again when cooled.Amorphous polymers have a loose and random molecular structure, so that in some cases amorphous materials are transparent. Both types of polymers can benefit from improved heat transfer and reduced cooling time.The following are some differences that need to be realized to provide a better understanding of the application.•Crystalline materials have a sharp melting point, and thus a latent heat energy that must be added when melting, and removed when cooling. The plastic needs to be solidified and cooled below the heat deflection temperature before ejection from the mold. The heat deflection temperature (HDT) is available on most resin datasheets. Just getting below the melting point is not enough. The part has to be cooled to the point where it is stiff enough to eject. Glass and mineral fillers increase the crystallization rate and the HDT so the part can be ejected at a higher temperature without deformation.•Amorphous polymers do not have a melting point, but as the heat input is increased above the glass transition temperature (Tg), the viscosity of the polymer decreases until it begins to flow. Heat is added until the plastic can flow adequately to fill the mold. Then the heat has to be removed until the polymer is below the Tg—in many cases before the part will be stiff enough to be ejected.In general, crystalline polymers contain more heat energy due to the latent heat. For example polycarbonate—which is amorphous—has a heat capacity of 1.2 J/(g oK) while polypropylene—which is semi-crystalline—has a heat capacity of 1.9 J/(g oK) or 58 percent higher. Molders will experience cycle time reductions and improved uniformity of cooling for both families of plastics when using high conductivity mold alloys.Some semi-crystalline materials—such as nylon—require relatively high mold temperatures to provide good surface finish and maximum crystallinity. High conductivity mold alloys can improve both characteristics, and reduce cycle time as an added bonus.This effect is achieved by simply running the mold at the desired temperature—for example 180oF. The high conductivity alloy will be able to remove heat faster than steel, but at the recommended temperature, and the heat removal will be more uniform. The result is reduced cooling time and more uniform crystallinity in the molded part. When molding amorphous plastics, uniform cooling also is very important. For clear polymers—like polycarbonate—the part will have better clarity and toughness.Water CoolingWith steel tools, molders often run chillers to reduce cycle times and to compensate for the reduced heat transfer of the steel. The cold tool will often result in condensation on the mold surface that can adversely affect part quality. With high-conductivity tool alloys, the cooling water can be set at a higher temperature to prevent condensation, and yet achieve much faster cycles than steel tools. Also, the surface temperature of the mold will be very close to the water temperature setpoint. The long-term heat transfer performance of copper alloys is very good, because copper resists corrosion and bio-fouling in the cooling channels.EconomicsCycle time reduction always has been a key effort for molders. Increasingly, molders are attempting to improve cycles to offset higher resin, energy and transportation costs that they have not been able to pass through to their customers. Using copper mold alloys allows molders to improve their production rate, avoid capital investment and minimize quality issues.Higher conductivity molds provide more uniform cooling than steel tools, resulting in better dimensional control, decreased warpage and part strength improvements. Payback analysis for molds using high-performance alloys yields very desirable numbers due to the reduced cooling times.Figure 2: Copper beryllium insert stands up well to the glass-filled nylon used in chair bases.Applications1. Recently, in the case of a large polyethylene lid, the molder calculated thepayback at 10 days using a copper beryllium insert in a steel tool. The cycle time was reduced from 75 seconds to 52 seconds, and allowed the molder to avoid purchasing an additional molding machine to keep up with demand. Capital avoidance is sometimes overlooked, but can be of tremendous benefit in the long term.2. Another example is a chair base made of glass-reinforced nylon. Themanufacturer was able to obtain a 20 percent cycle time reduction using copper beryllium for a core insert in the chair base mold (see Figure 2). Prior to using copper beryllium, the manufacturer was using strictly steel in its molds. After switching to molds using copper beryllium inserts they have witnessed a decrease in cycle from 122 seconds to 98 seconds—allowing for faster production throughout. Also, the dimensional control of the hub diameter was improved.By using copper beryllium, the manufacturer was able to increase annual production by 500,000 chair bases without purchasing additional injection molding machines. With all steel tools, four additional presses were required to meet the growing demand Again, major capital outlay was avoided for a minimal investment in high conductivity mold alloys.ConclusionThe benefits of high conductivity alloys include (1) faster cycle times, (2) uniform mold temperature, (3) better part quality, (4) low-maintenance cooling channels, (5) and suitability for amorphous and crystalline polymer families. Mold builders that have expertise and capabilities with these mold alloys have a competitive edge in a global marketplace. Such moldmakers can offer their customers high-performance molds that will enable their customers to be more competitive and profitable. And we all know that profitable customers are the best kind.。
机械论文的外文参考文献1
机械论文的外文参考文献11、‘‘How can a bill of materials be de?ned so that all possible products can be built ef?ciently?’’ One way to answer it is to de?ne a set of components (called modules), each of which contains a set of primary functions. An individual product is then built by combining selected modules.【1】Bruno Agard,Bernard Penz. A simulated annealing method based on a clustering approach to determine bills of materials for a large product family. Int. J. Production Economics 117 (2009) 389–401.2、In this study, we propose a methodology for building a semantically annotated multi-faceted ontology for product family modelling that is able to automatically suggest semantically-related annotations based on the design and manufacturing repository.【2】Soon Chong Johnson Lim,Ying Liu,Wing Bun Lee.A methodology for building a semantically annotated multi-faceted ontology for product family modelling. Advanced Engineering Informatics 25 (2011) 147–161.3、The aim of this work is to establish a methodology for an effective work ing of Recon?gurable Manufacturing Systems (RMSs). These systems are the next step in manufacturing, allowing the production of any quantity of highly customised and complex products together with the bene?ts of mass production.【3】R.Galan,J.Racero,I.Eguia,J.M.Garcia. A systematic approach for product families formation in Recon?gurable Manufacturing Systems.Robotics and Computer-Integrated Manufacturing 23 (2007) 489–502.4、A mixed integer linear programming model isinvestigated that optimizes the operating cost of the resulting supply chain while choosing the product variants and can de?ne the product family and its supply chain simultaneously.【4】Jacques Lamothe,Khaled Hadj-Hamou,Michel Aldanondo. An optimization model for selecting a product family and designing its supply chain. European Journal of Operational Research 169 (2006) 1030–1047.5、This paper presents LCP-families, a concept to develop reference ranges for environmental impact of a new product. A new product can be catalogued as environmentally better or worse than a percentage of its competitors, depending on what position it occupies in its LCP-family.【5】Daniel Collado-Ruiz,Hesamedin Ostad-Ahmad-Ghorabi. Comparing LCA results out of competing products: developing reference ranges from a product family approach. Journal of Cleaner Production 18 (2010) 355–364.6、This paper has proposed a cooperative coevolutionary optimization method for optimal design of product family with multi–level commonality .【6】L.Schulze,L.Li. Cooperative Coevolutionary Optimization Method for Product Family Design.7、This paper characterizes a decision framework by whicha ?rm can manage generational product replacements under stochastic technological changes.【7】Heng Liu,Ozalp Ozer. Managing a product family under stochastic technological changes. Int. J. Production Economics 122 (2009) 567–580.8、This paper proposes an information search and retrieval framework based on the semantically annotated multi-facet product family ontology to save time for the ontologydevelopment in design engineering.【8】Soon Chong Johnson Lim,Ying Liu,Wing Bun Lee. Multi-facet product information search and retrieval using semantically annotated product family ontology. Information Processing and Management 46 (2010) 479–493.9、The purpose of the paper is to present Product V ariety Analysis (PVA) approach to coordinated and synchronized fows of information about products and production processes among various supply chain members.【9】Petri Helo,Qianli Xu,Kristianto,Roger Jianxin Jiao. Product Family Design And Logistics Decision Support System.10、The purpose of this paper is to propose a product family design architecture that satisfies customer requirements with minimal efforts.【10】Taioun Kim,Hae Kyung Lee,Eun Mi Y oun. Product Family Design based on Analytic Network Process.11、This paper presents a conceptual framework of using semantic annotation for ontology based decision support in product family design.【11】Soon Chong Johnson Lim,Ying Liu,Wing Bun Lee. Using Semantic Annotation for Ontology Based Decision Support in Product Family Design。
机械设计类英文文献及翻译
The Sunflower Seed Huller and Oil PressBy Jeff Cox-- from Organic Gardening, April 1979, Rodale PressIN 2,500 SQUARE FEET, a family of four can grow each year enough sunflower seed to produce three gallons of homemade vegetable oil suitable for salads or cooking and 20 pounds of nutritious, dehulled seed -- with enough broken seeds left over to feed a winter's worth of birds.The problem, heretofore, with sunflower seeds was the difficulty of dehulling them at home, and the lack of a device for expressing oil from the seeds. About six months ago, we decided to change all that. The job was to find out who makes a sunflower seed dehuller or to devise one if none were manufactured. And to either locate a home-scale oilseed press or devise one. No mean task.Our researches took us from North Dakota -- hub of commercial sunflower activity in the nation -- to a search of the files in the U.S. Patent Office, with stops in between. We turned up a lot of big machinery, discovered how difficult it is to buy really pure, unrefined vegetable oils, but found no small-scale equipment to dehull sunflowers or press out their oil. The key to success, however, was on our desk the whole time. In spring 1977, August Kormier had submitted a free-lance article describing how he used a Corona grain mill to dehull his sunflower seeds, and his vacuum cleaner exhaust hose to blow the hulls off the kernels. A second separation floated off the remaining hulls, leaving a clean product. We'd tried it, but because some kernels were cracked and the process involved drying, we hadn't been satisfied. Now we felt the best approach was to begin again with what we learned from Mr. Kormier and refine it.Staff Editor Diana Branch and Home Workplace Editor Jim Eldon worked with a number of hand- and electric-powered grain mills. While the Corona did a passable job, they got the best results with the C.S. Bell #60 hand mill and the Marathon Uni Mill, which is motor-driven. "I couldn't believe my eyes the first time I tried the Marathon," Diana says. "I opened the stones to 1/8th inch, and out came a bin full of whole kernels and hulls split right at the seams. What a thrill that was!"She found that by starting at the widest setting,and gradually narrowing the opening, almost every seed was dehulled. The stones crack the hulls open, then rub them to encourage the seed away from the fibrous lining. The Bell hand mill worked almost as well. "As long as the stones open at least as wide as the widest unhulled seed, any mill will work," she says.Because the seed slips through the mill on its flat side, grading is an important step to take before dehulling. We made three sizing boxes. Thefirst is 1/4-inch hardware cloth [wire screen]. The second is two layers of1/4-inch cloth, moved slightly apart to narrow the opening in one direction, and the third is two layers of screen adjusted to make a still-smaller opening. Since the smallest unhulled seeds are about the size of the largest hulled kernels, the grading step prevents these undersized seeds from passing through unhulled. Processed together at a closer setting, the smallest seeds hulled out.Jim Eldon's workshop is littered with strange-looking pieces of apparatus. They represent initial attempts to build a workable winnowing box, using Kormier's vacuum exhaust idea for a source of air. Jim, Fred Matlack and Diana finally made a box with a Plexiglas front, through which they could observe what was happening.They cut a hole in the back of the box with a sliding cover to regulate the air pressure, and fiddled with various arrangements of baffles. The result was a stream of hulls exiting through one hole while the kernels fell to the bottom of the box. Now they were ready to try a five-pound sample of unhulled sunflower seeds to see how much they could recover.The five pounds were graded and dehulled, then winnowed. We got about one hull for every ten kernels in the final, winnowed product. These are easily picked out. They usually contain kernels still held behind the fibrous strings of the hull. Their weight prevents them from blowing out with the empty hulls. We found that bug-eaten seeds do blow away with the chaff, which was a bonus for cleanliness of the final product. Toss the hulls to the birds, who will find broken seeds among them.Starting with 80 ounces of unhulled seed, we ended up with 41-1/4 ounces of edible whole seeds, 1.8 ounces of damaged seeds suitable for animal feed, and 36.6 ounces of hulls. It took us about an hour. Notbad.Sunflower seeds store perfectly in the hulls, but they deteriorate more rapidly when shelled out. The grain mill dehuller and winnowing box give the gardener a way to have the freshest possible seeds for eating at all times of the year. With the construction of one more piece of equipment -- the oil press -- he can have absolutely fresh, unrefined, polyunsaturated sunflower oil for salads, mayonnaise and cooking.Most light, refined vegetable oils have been extracted using hexane, a form of naphtha. The oil is then heated to boil off the hexane. Lye is dumped into it. It's washed with steam, then heated to remove odors and taste before being laced with preservatives and stabilizers. It may feel oily in the mouth, but you might as well taste air. No so with fresh-made sunflower oil -- it's deliciously yet subtly nutty in flavor, adding unsurpassed flavor to salads.There's good reason to believe that sunflower oil may become the #1 vegetable oil in the U.S. in a few years. It's already #1 in health-conscious Europe. Corn oil has already caught on here for health reasons, and sunflower oil is so much better. Sunflower oil's 70 percent polyunsaturate is just under safflower, with corn oil bringing up the rear with 55 percent. And sunflowers yield 40 percent oil, soybeans only 20 percent.Our oil press isrelatively simple, but it must be welded together. Check the construction directions for details. The press consists of a welded tubular frame which accepts a three-ton hydraulic jack. You may already have one. If not, it can be purchased at most auto and hardware stores for about $16. A metal canister with holes drilled in its sides and one end welded shut holds the mashed sunflower seeds. A piston is inserted in the canister and then inverted and slipped over a pedestal on the frame. The jack is set in place, and the pressure gradually increased over half an hour. The oil drips from the sides of the canister into a tray -- the bottom of a plastic jug slipped over the pedestal works fine -- which empties the oil into a cup. You can filter the oil with a coffee filter to remove pieces of seed and other fine particles that would burn if the oil were used for cooking. If it's for salads or mayonnaise, there's no need to filter it.We first tried using "confectionary" sunflower seeds for oil. These are the regular eating kernels we're used to seeing. They give less than half as much oil as the oilseed types of sunflower. Although you can use confectionary types such as MAMMOTH RUS- SIAN for oil, don't expect to get more than an ounce and a half from a pound of seed. Oilseed produces three or more ounces of oil from a pound of seed and is well worth planting along with confectionary-type seeds. Oilseed has another big advantage -- to prepare it, you can put the whole, unhulled seed into a blender and whiz it until it forms a fine meal, while confectionary seeds must be dehulled first. The entire sequence of grading, dehulling and winnowing is avoided with oilseed.Oil types produce about a tenth of a pound of seed per head in commercial production. Gardeners, with their better soil and care, invariably do better than that. Our conservative estimate is that 1,280 plants will be enough for three gallons of oil. Spaced one foot apart in rows two feet apart, 1,280 oilseed plants will take a space 40-by-56 feet, or 80-by-28 if you want a more rectangular patch to face south.We worked in pound batches, since the canister just holds one pound of mash. After blending, we heated it to 170 degrees F. (77 deg C) by placing it in a 300-degree F. (149 deg C) oven and stirring it every five minutes for 20 minutes. Heating gets the oil flowing and doubles the yield of oil. In case you're wondering,"cold-pressed" oils sold commercially are also heated, and some are subjected to the entire chemical process. The term has no firm meaning within the industry, according to the literature we've surveyed.Heating does not change the structure of fats. It will not turn polyunsaturated fats into saturated fats. In fact, Dr. Donald R. Germann in his book, "TheAnti-Cancer Diet", says that "... an unsaturated fat must be heated to high temperatures -- above 425 degrees F. or 200 degrees C. -- at least 8 or 10 times before any shift toward saturation occurs..." Dean C. Fletcher, Ph.D., of the American Medical Association Department of Foods and Nutrition in Chicago, says, "It's true that either high temperature or repeated heatingdoes change the nature of some of the unsaturated oil molecules. (But) the flavor of the oil changes as these chemical changes occur, spoiling its taste. This effect is probably more profound than any of the physiological changes the altered oil might produce within the body."From 500 gm. of heated mash, we pressed 89 gm. of oil, 89 percent of the entire amount available and twice as much as we could press from unheated oil! The decision is up to you whether or not to heat the mash, but that extra 50 percent seems like an awful lot, especially when the whole technique is so labor intensive. The oil should be stored in the refrigerator, and it's probably best to use it within a month, since it has no preservatives. Mayonnaise made with such fresh oils should be kept refrigerated and used within two weeks. The leftover cake, still containing 50 percent of its oil, is a nutritious addition to your dishes, and makes excellent feed for animals or winter birds. Store the pressed cake in the freezer.We're talking then about a sunflower patch with two kinds of plants -- confectionary such as MAMMOTH RUSSIAN and oilseed such as PEREDOVIK. The oilseed plants should be grown 12 inches apart in rows two feet apart. Four average confectionary heads yield about a pound of unhulled seed. You'll need about 35 pounds of unhulled seed, or 140plants-worth, to yield 20 pounds of hulled kernels, about what a family of four will use in a year. That many plants can be grown in an area 26-by-10 feet. That's 260 square feet. Put that together with the 2,240 square feet for the oilseed sunflowers, and you need a patch about 2,500 square feet -- 25 100-foot rows -- to keep yourself supplied year-round with super nutrition and unsurpassable taste.Winnowing Machine For Sunflower SeedsThe winnowing machine operates on the age-old principle of blowing the chaff away from the heavy grain with a controlled current of air.The unit uses a household or shop-type vacuum cleaner for its air supply. A vacuum cleaner was used as a power source because it can supply a large volume of air over an extended period of time, and most homes and farms have a vacuum cleaner.A cloth bag has been attached to the chaff chute to catch the chaff as it is separated from the seed. The bag allows the hulls to be collected and greatly reduces the amount of waste material normally blown into the air by conventional systems.The unit has been constructed in such a way that the cloth bag and cleaner box can be placed inside the seed box, making a compact package for storage.Tools Required1. Table Saw2. Drill Press3. Band Saw4. Saber SawProcedure (cleaner box)1 . Cut out the two sides of the cleaner box from 1/4-inch plywood.2. Cut out the six interior pieces of the cleaner box from 3/4 x 3-1/2-inch select pine.3. Assemble the cleaner box elements with glue and nails.4. Cut four 1/4-inch square strips of pine four inches long.5. Glue the strips around the end of the chaff chute.6. Sand all surfaces and edges.7. Finish with clear lacquer finish.Procedure (seed box)1. Cut two pieces of pine /34" x 5 /12 x 15 inches for the sides.2. Cut two pieces of pine 3/4 x 5-1/2 x inches for the top and bottom.3. Plow a /14 x 1/4 groove for the front and back panels in all four pieces.4. Rip the top board to 5 inches so that the front panel can slide into the grooves in the side boards.5. Rabbet both ends of each 15-inch side piece to accept the top and bottom boards.6. Drill a hole in the left side board 2-1/2 inches from the top. The size of the hole is determined by the vacuum cleaner hose fitting.7. Cut a 3-1/4 x 4 inch hole in the top 1/2 inch from the right end. This hole will accept the cleaner box.8. Cut two pieces of pine for the baffle.9. Drill two 1-inch holes in the bottom of the baffle box.10. Cut a piece of 1/4 x 8-1/2 x 14 inch plywood for the back panel.11. Cut a 3-inch hole, centered 1-7/8 inches from the top and left sides of the plywood back.12. Assemble the sides, baffles, top, bottom, and back panel with glue and nails.13. Cut an 8-7/16 x 15-3/4-inch piece of Plexiglas for the front.14. Cut a one-inch radius on the top corners of the front.and sand the edges.15. Drill a one-inch thumb hole centered 7/8 inch from the top edge.16. Cut a 3-1/2-inch disk of 1/4-inch plywood for the vent cover.17. Drill a 3/16-inch hole 3/8 inch from the edge of the disk.18. Mount the disk over the vent with a #10 x 1-inch screw.19. Sand all surfaces and edges of the, box.20. Finish with clear lacquer finish.MaterialsCleaner Box2 -- 7-3/4 x 7-1/2 x 3/4" plywood (sides)6 -- 3/4 x 3-1/2 x 24" for all members (baffles)4 -- 1/4 x 1/4 x 4" pine (chute cleats)22 -- 1" x 18 ga. headed nailsWhite vinyl glueClear lacquer finishSeed Box2 -- 3/4' x 5-1/2 x 15" select pine (sides)2 -- 3/4 x 5-1/2 x 8-1/2" select pine (top and bottom)1 -- 3/4 x 3-1/2 x 4-1/2" select pine (baffle)1 -- 3/4 x 4-1/2 x 4-1/2" select pine (baffle)1 -- 1/4 x 8-1/2 x 14" plywood (back)1 -- 1/4 x 3-1/2" dia. plywood (control valve)1 -- 1/4' x 8-7/16 x 15-1/4" Plexiglas (front)1 - #10 x 1" flat head screw18 - 4d finish nailsWhite vinyl glueClear lacquer finish1 -- 17 x 31" cloth laundry bagSunflower Seed Oil PressThe press was designed so that homesteaders can produce sunflower oil from their own seeds. The oil can be pressed as is or heated to 170 degrees F., which doubles oil yield.Both methods require the seed to be ground to fine powder. If you are pressing the oil seed variety, a meat grinder or electric blender will do an excellent job of grinding the seed. The confectionary type of seed will require the seed to be hulled and winnowed before it is ground. A food mill with the stones set at the coarse setting can be used to accomplish this step. The ground kernels are placed in the cylinder with the piston closing the bottom portion of the cylinder.The cylinder is mounted in the press frame and a three-ton hydraulic jack is used to supply the pressure.Because of the great pressures created by the hydraulic jack, it is important that the frame be properly constructed and firmly mounted to the work surface before the pressing operation begins. The following instructions can be given to a welder.Tools Required1. Power Hacksaw2. Metal Band Saw3. Metal Lathe4. Drill Press5. Belt or Disk Grinder6. Arc Welder7. Hand ClampsProcedure (Frame)1. Cut two pieces of 1-3/4" O.D. x 1-3/8" I.D. x 24-1/2 inch long tubing for the uprights.2. Cut one piece of 1-3/4" O.D. x 1-3/8" I.D. x 6-1/2 inch long tubing for the center tube.3. Cut one 3/4" x 2-3/4 x 5-1/2 inch steel bar for the top cross member.4. Cut two pieces of 1-3/4 x 1-3/4 x 8 inch angle iron for the base members.5. Drill two 9/32-inch holes in each base member 1/2 inch from the outer edges.6. Weld the base members, tubes and cross member together as per the drawing.7. Grind all edges to remove any burrs.8. Paint the frame.9. If a mounting board is desired, cut a piece of pine 1-1/4 x 6-1/2 x 12 inches long.10. Center the frame on the board and mark the location of the four mounting holes.11. Drill four 7/8-inch holes 1/4-inch deep to accept the T-nuts.12. Drill four 5/16-inch holes through the mounting board using the same centers created by the 7/8-inch holes.13. Round the edges of the base and sand all surfaces.14. Install four 1/4-20 T-nuts.15. Finish the base with clear lacquer finish.16. Assemble the base to the frame using four 1/4-20 x 1-1/4-inch round head bolts.Procedure (Cylinder)1. Cut a piece of 3-1/2" O.D. x 3-1/4" I.D. tubing 5-3/8 inches long.2. Face both ends on the lathe.3. Cut out a 3-1/2-inch round disk from 1/4-inch plate steel.4. Weld the disk to one end of the tube.5. Drill a series of 3/32-inch holes around the side of the tube on 1/2-inch centers.6. Remove all burrs on the inside and outside of the tube.Procedure (Piston)1. Cut out a 3-3/8-inch disk of 1/4-inch plate steel.2. Cut a 1-3/8" O.D. x 1-1/8" I.D. piece of tubing 1-1/8 inches long.3. Face both ends of the tube.4. Weld the tube in the center of the 3-3/8-inch disk. All welds should be made on the inside of the tube.5. Mount the piston in the lathe and turn the disk to fit the inside diameter of the cylinder. This will be about 3-15/64 inches in diameter.6. Remove any sharp edges.Procedure (Collector Ring)1. Cut the bottom out of a one-gallon plastic bottle. The cut line should be approximately 1-1/2 inches from the bottom of the bottle.2. Make a 1/8 x 1 inch slot at one edge of the bottom outside ring. This will allow the oil to pour into a receiving cup.3. Cut a 1-3/4-inch hole in the center of the bottom, so that the unit will fit over the center tube in the frame.MaterialsFrame2 -- 1-3/4 O.D. x 1-3/8 I.D. x 24-1/2" long H.R.S. (frame tubes)1 -- 1-3/4 O.D. x 1-3/8 I.D. x 6-1/2 inch long H.R.S. (center tube)1 -- 3/4 x 2-3/4 x 5-1/2" flat bar H.R.S. (top cross member)2 -- 1-3/4 x 1-3/4 x 8" angle iron H.R.S. (base members)1 -- 1-1/4 x 6-1/2 x 12" #2 white pine (wood base)4 -- 1/4-20 x 1-1/4 R.H. mounting bolts4 -- 1/4-20 T-nutsBlack enamel for frame (finishing material)Clear lacquer finish for wood base3 -- 1/8" dia. welding rodsCylinder1 -- 1/4 x 3-1/2" dia. C.R.S. disk (top)1 -- 3-1/2 O.D. x 3-1/4 I.D. C.R.S. tube (cylinder)1 -- 1/8 dia. welding rodPiston1 -- 1/4 x 3-3/8 D.A. C.R.S. disk (piston top)1 -- 1-1/4 O.D. x 1 I.D. x 1" long H.R.S. (piston tube)1 -- 1/8 dia. welding rodCollector Ring1 -- Bottom from a one-gallon plastic bottle (oil collector ring)葵花籽脱壳机和油压机由Jeff考克斯-从有机园艺，1979年4月，罗代尔新闻2,500平方尺，一个四口之家每年可以长到足以产生三种葵花籽国产蔬菜沙拉或烹调油和20磅的营养丰富，适合脱皮加仑种子 - 与遗留养活一个冬天的产值，破碎的种子鸟类。
机械设计外文参考文献
Fig. 1 A fully coupled three-discipline non hierarchic system3 Formulation and Implementation3.1 Formulation. As aforementioned, the confliction of shared variables brings organizational and computational troubles. In this paper, a coordinator is introduced to the typical bi-level CO framework to handle the confliction. The formulation is shown in Fig.2.The system level problem is solved by an MOEA, in which each individual of the population is evaluated according to the valuesreturned from discipline optimizers and middle coordinator. After that, the offspring is generated by the evolutionary operators, such as selection, crossover, and mutation in genetic algorithm. The fitnessfunctionf/ in the system optimizer is composed of the disciplinary objective function /; and a penalty term PI, where I is the smallest discrepancy of the shared variables given by the middle coordinatorand P is a penalty coefficient defined by the user, P is set as 103 in this paper. The design variables in the system optimizer annotated as (-)' include shared variables Xsh and auxiliary variables (p, both of whichare targets for the discipline optimizer to match.The discipline optimizer employs SQP to find a design, whichmatches the target values from the system level to maintain the multilevel compatibility and synchronously satisfies both the dis-ciplinary constraints and interdisciplinary compatibility. The com-patibility tolerance e is set to be 10-3in this paper. The output state variable vector Yik is calculated by the disciplinary state equation <1>(-). Parameters of (-)' are transferred from the system level, which are considered constant at the subsystem level. The design variables at the subsystem level annotated as (-)d are composed of shared variables Xshi, local variables Xli, and input state variables Yp. It can be seen that the design variables of a discipline after decomposition are the same as those before decomposition, i.e., the design freedom remains the same, which gives the most104502-2 I Vol. 133, OCTOBER 2011 Fig. 2 Formulation of proposed MOCOTransactions of the ASME。
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Record: 1
Title:Horizontal Drilling Injects Life Into Fields.
Authors:PATRICK CAIN
Source:Investors Business Daily; 10/5/2010, pB03, 1p
Document Type:Article
Abstract:Master limited partnerships are a special class of investments,
as detailed in Monday's Income Investor. Today, let's look at
what's happening now in this hot field. [ABSTRACT FROM
PUBLISHER]
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Full Text Word Count:335
ISSN:10612890
Accession Number:54096375
Database: Business Source Complete
Horizontal Drilling Injects Life Into Fields
MARKET COVERAGE
THE INCOME INVESTOR
Investing
Master limited partnerships are a special class of investments, as detailed in Monday's Income Investor. Today, let's look at what's happening now in this hot field.
These businesses, which usually are natural gas and oil midstream companies, have outperformed many "safe" investments such as 10-year Treasuries, Moody's Baa bonds and the S&P 500 index.
Going forward, growth is largely tied to location.
Drilling in shale for natural gas has been done for years, using a process known as vertical drilling. With that came infrastructure, as gas-rich areas like Texas and Louisiana needed to find ways to ship it to the major cities across the country.
This laid the groundwork for today's firms being in ripe positions. Laying thousands of miles of pipeline is expensive and acts as a barrier to entry. Plus, the existing gas and oil fields and their respective pipeline corridors are essentially fully occupied.
In the last decade, drillers have created a new way to drill down and then over nearly a mile —horizontal drilling. This revived the dormant fields and companies didn't need to add the expensive pipeline, as it was already in place.
Today Barnett, Haynesville and the Marcellus shale fields are three of the major hotbeds for midstream companies. Companies are swooping in and making acquisitions.
But there are risks to consider going forward. There's regulatory risk with interstate tariffs. Another is that tax laws could also change, which could threaten the foundation of MLPs. One other fear is these firms need constant external equity and debt financing.
But so far MLPs have shown they can find financing, even in hard times. From December 2008 through June '09, they raised $7.45 billion, according to "The Handbook of Infrastructure Investing" by Michael Underhill.
PATRICK CAIN
Copyright 2010 Investor's Business Daily, Inc. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed without permission.
~~~~~~~~
By PATRICK CAIN
Copyright of Investors Business Daily is the property of Investor's Business Daily and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.。