外文翻译--液压技术在军工业中的应用

外文原文：
Hydraulic Technology in Industry
Hydraulic technology generally used in heavy, large, extra large equipment, such as metallurgical industry, rolling mill gauge control system, continuous casting machine pressure systems.
Military situation in the high-speed response, such as aircraft rudder control, ship steering control, high-speed response with the dynamic system.
Construction machinery, impact, required a relatively high power systems are generally heavy hydraulic systems.
Application of the above three areas are the best in the field of hydraulic technology Pressure transmission control is often used in industry as a control method, which uses hydraulic pressure to complete the process of transfer of energy. Hydraulic control method for the flexibility and convenience, the hydraulic control in the industry are widely appreciated. Is to study the hydraulic fluid to a pressure medium for the energy to achieve a variety of mechanical and control subjects. Hydraulic components used to form such a variety of control loops required, then a number of circuits, some combination of a complete transmission system control functions to accomplish energy transfer, conversion and control.
Theoretically, the hydraulic transmission is based on the most basic principle is the Pascal principle, that is, fluid pressure is the same everywhere, so in a balanced system, the relatively small pressure above the piston is relatively small, but large piston pressure is relatively large, it can still maintain a liquid. So, passing through the liquid, can be different on different side pressures, so that you can achieve a change of purpose. Our common to the hydraulic jack is used to achieve the power of this principle of transmission.
The basic principles of hydraulic.
Hydraulic components needed in the main power components, the implementation of components, control components, auxiliary components, etc.. One hydraulic power hydraulic system components for the power components, including a variety of hydraulic pumps. Pump principle to rely on changes in work volume, it is generally also known as volume hydraulic pump. Gear pump is the most common type of hydraulic pump that uses two rotating gears meshing allows the liquid to exercise. There are other hydraulic vane pump, piston pumps, hydraulic pump, when in the choice of the main issues requiring attention include the consumption of energy, efficiency and reduce noise.
Hydraulic actuator is used to perform the hydraulic pump to provide hydraulic energy into mechanical energy devices, including hydraulic cylinders and hydraulic motors. Hydraulic pump hydraulic motor is doing the opposite of work with the device, that is, the
hydraulic energy conversion is called mechanical energy to do work outside.
Hydraulic control unit to control the direction of liquid flow, pressure, flow level and the size of the expected controls to meet specific job requirements. It is because of the flexibility of hydraulic control components, make hydraulic control system to perform different activities. Hydraulic control components in accordance with the purpose can be divided into pressure control valves, flow control valves, directional control valves. In accordance with the mode of operation can be divided into human control valve, mechanical control method, electric control valve.
In addition to the other components, hydraulic control system also needs auxiliary hydraulic components. These components include piping and fittings, tanks, filters, accumulators, and seal. All the above devices, we can build a hydraulic circuit. The so-called hydraulic circuit is formed through a variety of hydraulic devices corresponding control circuit. Depending on the control objectives, we can design different circuits, such as pressure control loop, speed control loop, multi-cylinder control circuit, etc. work.
According to the structure and characteristics of hydraulic transmission, the hydraulic system design, system analysis first, then develop the system diagram, which is the schematic symbol to represent the hydraulic machinery. After selection by calculating the hydraulic device, which can then complete the system design and debugging. This process, the principle of mapping is the key. It determines the merits of a design system.
The application of hydraulic transmission is very strong, such as loading and unloading stacking machine hydraulic system, which as a storage machine, in the modern warehouse use it to achieve textile bags, barrels, casks and other cargo handling is mechanical. Can also be used in universal cylindrical grinding machine hydraulic system and other production practices. These systems are characterized by relatively large power, more efficient production, stability is better.
As a widely used hydraulic technology, the future is a bright future. With the deepening development of a computer, hydraulic control system can intelligent control technology, computer technology, control technology together, so that more places will be able to play a role, but also can be more compact, more flexible to accomplish the tasks expected of control tasks.
Hydraulic fluid power transmission is one of the basic principle is in a closed container, the pressure of the oil used as a working medium to achieve energy conversion and transmission of power. One of the liquid as the working medium, usually mineral oil, its role and mechanical transmission of the belts, chains and gears and other transmission components are similar.
Hydraulic system consists of: Power components (pumps), the implementation of components (cylinder or hydraulic motor), control elements (all valve), auxiliary
components and the work of the five media components.
Advantages and disadvantages of hydraulic
1、the advantages of hydraulic
(1) small size, light in weight, so less inertia, when a sudden overload or stop when the big impact will not occur;
(2) can be stable within a given range automatically adjust traction speed, and can realize stepless speed regulation;
(3) for the easy, without changing the motor rotation direction of the case, you can more easily work agencies to achieve the reciprocating motion of rotation and conversion;
(4) hydraulic pump and a pipeline between the hydraulic motor connected to each other in space without strict limits on the layout;
(5) The use of oil as the working medium, the relative motion between the surface components can self-lubricating, wear small, long life;
(6) easy manipulation of control, high degree of automation;
(7) easy to implement overload protection.
2、hydraulic transmission defects
(1) the use of hydraulic transmission requirements on the maintenance of high oil should always work to keep clean;
(2) manufacture of high precision hydraulic components, process complexity, high cost;
(3) maintenance of more complex hydraulic components, and the need for a higher technical level;
(4) oil to do the work of media, the existence of fire hazards in the face;
(5) The transmission efficiency is low.
中文译文：
液压技术在工业中的应用
液压技术一般应用于重型，大型，特大型设备，如冶金行业轧机压下系统，连铸机压下系统等。

军工中高速响应场合，如飞机尾舵控制，轮船舵机控制，高速响应随动系统等
工程机械，抗冲击，要求功重比较高系统一般都采用液压系统。

以上三个领域是应用液压技术的最大领域。

压传动控制是工业中经常用到的一种控制方式，它采用液压完成传递能量的过程。

因为液压传动控制方式的灵活性和便捷性，液压控制在工业上受到广泛的重视。

液压传动是研究以有压流体为能源介质，来实现各种机械和自动控制的学科。

液压传动利用这种元件来组成所需要的各种控制回路，再由若干回路有机组合成为完成一定控制功能的传动系统来完成能量的传递、转换和控制。

从原理上来说，液压传动所基于的最基本的原理就是帕斯卡原理，就是说，液体各处的压强是一致的，这样，在平衡的系统中，比较小的活塞上面施加的压力比较小，而大的活塞上施加的压力也比较大，这样能够保持液体的静止。

所以通过液体的传递，可以得到不同端上的不同的压力，这样就可以达到一个变换的目的。

我们所常见到的液压千斤顶就是利用了这个原理来达到力的传递。

液压传动基本原理。

液压传动中所需要的元件主要有动力元件、执行元件、控制元件、辅助元件等。

其中液压动力元件是为液压系统产生动力的部件，主要包括各种液压泵。

液压泵依靠容积变化原理来工作，所以一般也称为容积液压泵。

齿轮泵是最常见的一种液压泵，它通过两个啮合的齿轮的转动使得液体进行运动。

其他的液压泵还有叶片泵、柱塞泵，在选择液压泵的时候主要需要注意的问题包括消耗的能量、效率、降低噪音。

液压执行元件是用来执行将液压泵提供的液压能转变成机械能的装置，主要包括液压缸和液压马达。

液压马达是与液压泵做相反的工作的装置，也就是把液压的能量转换称为机械能，从而对外做功。

液压控制元件用来控制液体流动的方向、压力的高低以及对流量的大小进行预期的控制，以满足特定的工作要求。

正是因为液压控制元器件的灵活性，使得液压控制系统能够完成不同的活动。

液压控制元件按照用途可以分成压力控制阀、流量控制阀、方向控制阀。

按照操作方式可以分成人力操纵阀、机械操纵法、电动操纵阀等。

除了上述的元件以外，液压控制系统还需要液压辅助元件。

这些元件包括管路和管接头、油箱、过滤器、蓄能器和密封装置。

通过以上的各个器件，我们就能够建设
出一个液压回路。

所谓液压回路就是通过各种液压器件构成的相应的控制回路。

根据不同的控制目标，我们能够设计不同的回路，比如压力控制回路、速度控制回路、多缸工作控制回路等。

根据液压传动的结构及其特点，在液压系统的设计中，首先要进行系统分析，然后拟定系统的原理图，其中这个原理图是用液压机械符号来表示的。

之后通过计算选择液压器件，进而再完成系统的设计和调试。

这个过程中，原理图的绘制是最关键的。

它决定了一个设计系统的优劣。

液压传动的应用性是很强的，比如装卸堆码机液压系统，它作为一种仓储机械，在现代化的仓库里利用它实现纺织品包、油桶、木桶等货物的装卸机械化工作。

也可以应用在万能外圆磨床液压系统等生产实践中。

这些系统的特点是功率比较大，生产的效率比较高，平稳性比较好。

液压作为一个广泛应用的技术，在未来更是有广阔的前景。

随着计算机的深入发展，液压控制系统可以和智能控制的技术、计算机控制的技术等技术结合起来，这样就能够在更多的场合中发挥作用，也可以更加精巧的、更加灵活地完成预期的控制任务。

液压传动是流体传动的一种，其基本原理是在密闭的容器内，利用有压力的油液作为工作介质来实现能量转换和传递动力的。

其中的液体称为工作介质，一般为矿物油，它的作用和机械传动中的皮带、链条和齿轮等传动元件相类似。

液压系统主要由：动力元件（油泵）、执行元件（油缸或液压马达）、控制元件（各种阀）、辅助元件和工作介质等五部分组成。

液压传动的优缺点
1、液压传动的优点
（1）体积小、重量轻，因此惯性力较小，当突然过载或停车时，不会发生大的冲击；
（2）能在给定范围内平稳的自动调节牵引速度，并可实现无极调速；
（3）换向容易，在不改变电机旋转方向的情况下，可以较方便地实现工作机构旋转和直线往复运动的转换；
（4）液压泵和液压马达之间用油管连接，在空间布置上彼此不受严格限制；
（5）由于采用油液为工作介质，元件相对运动表面间能自行润滑，磨损小，使用寿命长；
（6）操纵控制简便，自动化程度高；
（7）容易实现过载保护。

2、液压传动的缺点
（1）使用液压传动对维护的要求高，工作油要始终保持清洁；
（2）对液压元件制造精度要求高，工艺复杂，成本较高；
（3）液压元件维修较复杂，且需有较高的技术水平；
（4）用油做工作介质，在工作面存在火灾隐患；
（5）传动效率低。