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中英文对照外文翻译文献(文档含英文原文和中文翻译)原文：FEATURE-BASED COMPONENT MODELS FOR VIRTUALPROTOTYPING OF HYDRAULIC SYSTERMAbstract:This paper proposes a feature-based approach for the virtual prototyping of hydraulic systems. It presents a framework which allows the designer to develop a virtual hydraulic system prototype in a more intuitive manner, i.e. through assembly of virtual components with engineering data. The approach is based on identifying the data required for the development of the virtual prototypes, and separating the information into behaviour, structural, and product attributes. Suitable representations of these attributes are presented, and the framework for the feature-based virtual prototyping approach is established,based on the hierarchical structure of components in a hydraulic system. The proposed framework not only provides a precise model of the hydraulic prototype but also offers the possibility of designing variation classes of prototypes whose members are derived by changing certain virtual components with different features.Key words: Computer-aided engineering; Fluid power systems;Virtualprototyping1.IntroductionHydraulic system design can be viewed as a function-to-form transformation process that maps an explicit set of requirements into a physical realisable fluid power system. The process involves three main stages: the functional specification stage,the configuration design stage, and the prototyping stage.The format for the description of the design in each stage is different.The functional specification stage constitutes the initial design work. The objective is to map the design requirements. To achieve this, the design problems are specified Correspondence and offprint requests to: Dr S. C. Fok, Schoool of Mechanical and Production Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798. The designer must identify the performance attributes, which can include pressure, force, speed, and flowrate, with the required properties such as size, cost, safety and operating sequence. performance requirements for each attribute. In this stage, the design is abstracted in terms of the performance attributes with associated values.The objective of the configuration design stage is to synthesise a hydraulic circuit that performs the required functions conforming to the performance standards within defined constraints. A typical hydraulic system is made up of many subsystems. The smallest building block in a subsystem is the standard hydraulic component (such as valves, cylinders,pumps, etc.). Each type of standard component serves a specific elemental function. The design effort in the configuration design stage is fundamentally a search for a set of optimal arrangements of standard components (i.e. hydraulic circuit) to fulfil the functional requirements of the system. Based on this framework, the designers would normally decompose the overall system functions in terms of subfunctions. This will partition the search space and confine the search for smaller hydraulic subcircuits to perform the subfunctions.Computers are often used to support the configuration design process. For example, Kota and Lee devised a graph-based strategy to automate the configuration of hydraulic circuits. After the development of the hydraulic circuits, digital simulation tools are often used to study and evaluate these configurations. With these tools, designers can compare the behaviour of different circuits and also analyse the effects when subcircuits are combined. In the configuration design stage, the design is traditionally represented as a circuit drawing using standard icons to symbolise the type of standard component. This is a form of directed graph S(C,E) where the circuit S contains components C in the form of nodes with relations between components denoted by edges E.The prototyping stage is the verification phase of the system design process where the proposed hydraulic circuit from the configuration design stage isdeveloped and evaluated. Physical prototyping aims to build a physical prototype of the hydraulic system 666 S. C. Fok et al. using industrial available components. The process of physical prototyping involves the following: Search for appropriate standard components from different manufacturers. Pre-evaluation and selection of components based on individual component cost, size, and specification, and compatibility factors between components. Procurement and assembly of the selected components.Test and evaluate the physical prototype based on the overall system requirements. Use other components or redesign the circuit (or subcircuits)if necessary.Besides dynamics, the development of the physical prototype must take into consideration other factors including structure,cost, and weight. The dynamics data are used to confirm the fluid power system behaviour whereas the geometric information is used to examine the assembly properties. The development of the physical prototype will provide the actual performance,structure, and cost of the design.The main disadvantage of physical prototyping is that it is very tedious and time consuming to look for a set of suitable combinations of standard components from among so many manufacturers. Although the basic functions of the same types of standard component from different manufacturers do not differ, their dynamics, structural and cost characteristics may not be similar, because of design variation. Hence, for a given hydraulic circuit, different combinations of parts from differentmanufacturers can have implications on the resulting system,in terms of dynamics, structure, and cost. Value engineering can be used at this stage to improve the system design by improving the attributes at the component level. This includes maximizing the performance-to-cost ratio and minimising the size-to-performance ratio. Virtual prototyping can be viewed as a computer-aided design process, which employs modelling and simulating tools to address the broad issues of physical layout, operationalconcept, functional specifications, and dynamics analysis under various operating environments. The main advantage of virtual prototyping is that a hydraulic system prototype can be assembled, analysed, and modified using digital computers without the need for physical components, thus saving lead time and cost.The main requirement of a virtual hydraulic system prototype is to provide the same information as a physical prototype for the designer to make decisions.To achieve this, the virtual prototype must provide suitable and comprehensive representations of different data. Furthermore, transformation from one representation to another should proceed formally. Xiang et al. have reviewed the past and current computer-aided design and prototyping tools for fluid power systems. The work revealed that the current tools could not provide a completerepresentation of the design abstractions at the prototyping stage for design judgement. Most of the tools concentrate on the dynamics behaviour. Vital geometrical and product information that relates to the system prototype consideration and evaluation is frequently missing.To advance the development of computer-aided virtual prototyping tools for fluid power systems, there is a need to address the formal representations of different abstractions of behaviour,structural, and product data along with their integration. This paper focuses on these issues and proposes the formalism of a unified component model and the taxonomy based on the feature-based approach. In Section 2, we discuss the feature- based approach focusing on the key information and their representations required for hydraulic system prototyping. Section 3 presents a formalism of the feature-based model and structure for the development of virtual hydraulic system prototypes.The structure is illustrated with an example. Future work and conclusions are given in Section 4.2. Feature-Based ApproachFeatures can be defined as information sets that refer to aspects of attributes that can be used in reasoning about the design, engineering or manufacturing processes. The concept of using features to integrate CAD/CAPP/CAM is not new and there are many papers on the application of this approach in CIM. In all these applications, the feature model is regarded as the basis whereas design by features is the key for the integration. To develop a feature model, the relevant information concerning the design must be identified and grouped into sets based on the nature of the information. The relevant information should contain sufficient knowledge for activities such as design, analysis, test, documentation, inspection, and assembly, as well as support various administrative and logistic functions. Design by features is the process of building a model of the design using features as primitive entities. The feature model provides the standardisation of relevant data. Through the design by features approach, vital knowledge of the design will be generated and stored. Together, the feature model and the design by features approach will provide the essential information, which can be used, not only for the simultaneous consideration of many different concerns with the design, but also to interface the many activities in the design realisation process, including the life cycle support operations. The main drawback of the feature-based design approach is that the feature model should be properly defined . This can be difficult, as features are sets of knowledge that are application dependent. The organisation of the features can also be application specific. Non-trivial data-management problems could arise if the feature model is not properly defined. To avoid these problems, the type,representation and structure of the features should be resolved prior to using the feature-based design methodology. The main concern when developing afeature model is that it is application-specific. In the domain of virtual prototyping of hydraulic systems, the details of the constituent standard components must be able to be used to describe the overall system. The component features are bearers of knowledge about that part. To create a suitable feature model for hydraulic system design based on the assembly of standard components, the relevant information associated with various standard components must be identified and classified. This definition Feature-Based Component Models 667 of the component feature set can then be extended to encompass the subsystem feature set based on the hierarchical structure between the components in the subsystem. In the same manner, a hierarchical structure for the hydraulic system feature representation would evolve by considering the system as a hierarchy of subsystems.The necessary information required for a proper description of the virtual prototype must be no less than that derived by the designer from a physical prototype for decision making. These data should generally include the shape, weight, performance properties, cost, dimensions, functionality data, etc. Comparison with the physical prototyping process, the information required for each standard component could be separated into three distinct groups: behaviour attributes, structural attributes, and product attributes.2.1 Behaviour AttributesThe behaviour of a hydraulic component can be defined in terms of the dynamics characteristics used to satisfy the functional requirements. Consider a hydraulic cylinder connected to a load. Its function is to transmit a force from the stroke of the piston to the load. The maximum force it can transmit can be used to define the functionality and the behaviour requirements can be specified in terms of the desired load acceleration characteristics. Hence for a hydraulic component, behaviour attributes express functionality and can be reflected in the dynamics characteristics. The designer is responsible for the proper definition of the overall system behaviour characteristics in terms of the desired dynamics. A standard component will have its own behaviour and provide a specific plex functions that cannot be achieved by a single standard component are derived using a combination of components. Hence, the behaviour of the standard component will play an important role as the individual behaviours of components together with their arrangement can alter the overall system function .The behaviour of a standard component can be nonlinear and can be dependent on the operating conditions. When two components are combined, it is possible that their behaviours can interact and produce undesired or unintended characteristics. These unwanted behaviours are assumed to have been resolved during the configuration design stage. The hydraulic circuit used in theprototyping stage is assumed to be realisable and without any undesirable interacting behaviours. This means that the output behaviour of a component will provide the input to the subsequent component.The representation of behaviours for hydraulic systems has been widely investigated. These representations include transfer functions, state-space and bond graphs. Transfer functions (for single-input–single-output systems) and state-space equations (for multiple-input–multiple-output systems) are based on the approximation of the dynamics about a nominal operating condition. The power bond graph model is based on the causal effects that describe the energy transformations in the hydraulic system. This approach is appealing for hydraulic system analysis. The main disadvantage is that the derivation of the dynamics equation in a bond graph of a complicated fluid power system can become very tedious. As a result, recent work has concentrated on the used of artificial intelligence to represent the nonlinear mapping between the input and output data, which can be obtained via experimental work. These nonlinear mappings can be accomplished using artificial neural networks .It is quite natural for a hydraulic system designer to use input–output data to describe the behaviour of a hydraulic component. The configuration design of a hydraulic system is often achieved through steps of function decomposition. To design a hydraulic system, the designer often tries to decompose the functions and their requirements down to the component level.译文：基于原型液压系统特征的机构模型摘要：本文为原型液压系统的设计提出了一种基于特征的方法。
中国地质大学长城学院本科毕业设计外文资料翻译系别工程技术系专业机械设计制造及其自动化学生姓名彭江鹤学号 05211534指导教师王泽河职称教授2015 年 5 月 4 日液压传动系统作者：Hopmans, ArthurH.摘要液压传动是由液压泵、液压控制阀、液压执行元件和液压辅件组成的液压系统。
液压泵把机械能转换成液体的压力能，液压控制阀和液压辅件控制液压介质的压力、流量和流动方向，将液压泵输出的压力能传给执行元件，执行元件将液体压力能转换为机械能，以完成要求的动作。
关键词：液压传动；气压传动；传动系统；许多液压传动先前已经设计出允许操作者无限变化输出的变速器，或甚至逆转的传动装置的输出作为相对于输入。
通常情况下，这已经通过使用一个旋转斜盘是要么由操作者手动或操作液压动机来改变通过旋转泵头部具有轴向移动的活塞流动的液压流体的。
液压流体从泵头活塞的流动，依次转动的马达头通过激励相应的一组活塞在其中违背一固定凸轮的，因此，旋转安装在电动机头的输出轴。
通常情况下，在现有技术的变速器已被被设置有各种功能，例如齿轮减速，刹车设定装置等。
不幸的是，这些功能通常是提供外部发送的和显著增加整个装置的体积和质量。
申请人确定，这是很期望具有其中基本上所有的这些需要或希望的功能，可以在内部提供的发送，同时还产生一个非常有效的和非常有效的传输的综合传输。
特别是，这种类型的变速器上经常使用的设备，如“零转动半径”剪草机之类的其中一个潜在的危险情况面对操作者，旁观者和设备本身，如果设备我们允许继续被推进应的操作者释放控制，由于当操作者无意中从装置抛出或变得受伤。
因此，“故障自动刹车”机制经常被设置为传输自动地返回到中立配置在这种情况下，使得该装置不会继续供电，如果控制被释放。
先前传输这种类型的一般依靠某种外部设备，比如其目的是为了在操作者控制轴返回到中立位置应操作者释放所述轴的反操作偏压弹簧。
这种类型的外部设备，可以容易地由用户或篡改损坏。
液压元件中英文对照伺服阀servo-valve 四通阀four-way valve喷嘴挡板nozzle flapper液压放大器hydraulic amplifier颤振dither阀极性valve polarity流量增益flow gain对称度symmetry流量极限flow limit零位内泄漏null(quiescent)leakage遮盖lap零遮盖zero lap正遮盖over lap负遮盖under lap开口opening零偏null bias零漂null drift阀压降valve pressure drop分辨率resolution频率响应frequency response 幅值比amplitude ratio相位移phase lag传递函数transfer function管路flow line硬管rigid tube软管flexible hose工作管路working line回油管路return line补液管路replenishing line控制管路pilot line泄油管路drain line放气管路bleed line流体传动hydraulic power液压技术hydraulics液力技术hydrodynamics气液技术hydropneumatics效率efficiency旋转方向direction of rotation 公称压力nominal pressure工作压力working pressure进口压力inlet pressure出口压力outlet pressure压降pressure drop；differential pressure 背压back pressure启动压力breakout pressure充油压力charge pressure开启压力cracking pressure峰值压力peak pressure运行压力operating pressure耐压试验压力proof pressure冲击压力surge pressure静压力static pressure系统压力system pressure控制压力pilot pressure充气压力pre-charge pressure吸入压力suction pressure调压偏差override pressure额定压力rated pressure耗气量air consumption泄漏leakage内泄漏internal leakage外泄漏external leakage层流laminar flow紊流turbulent flow气穴cavitation流量flow rate运行工况operating conditions额定工况rated conditions极限工况limited conditions瞬态工况instantaneous conditions稳态工况steady-state conditions许用工况acceptable conditions连续工况continuous working conditions实际工况actual conditions排量displacement额定流量rated flow供给流量supply flow流量系数flower factor滞环hysteresis图形符号graphical symbol液压气动元件图形符号symbols for hydraulic and pneumatic components流体逻辑元件图形符号symbols for fluid logic devices逻辑功能图形符号symbols for logic functions回路图circuit diagram压力－时间图pressure time diagram 功能图function diagram循环circle自动循环automatic cycle工作循环working cycle循环速度cycling speed工步phase停止工步dwell phase工作工步working phase快进工步rapid advance phase快退工步rapid return phase频率响应frequency response重复性repeat ability复现性reproducibility漂移drift波动ripple线性度linearity线性区linear region液压锁紧hydraulic lock液压卡紧sticking变量泵variable displacement pump泵的控制control of pump齿轮泵gear pump 叶片泵vane pump柱塞泵piston pump轴向柱塞泵axial piston pump法兰安装flange mounting底座安装foot mounting液压马达hydraulic motor刚度stiffness中位neutral position零位zero position自由位free position缸cylinder有杆端rod end无杆端rear end外伸行程extend stroke内缩行程retract stroke缓冲cushioning工作行程working stroke负载压力induced pressure输出力force实际输出力actual force单作用缸single-acting cylinder双作用缸double-acting cylinder差动缸differential cylinder伸缩缸telescopic cylinder阀valve底板sub-plate油路块manifold block板式阀sub-plate valve叠加阀sandwich valve插装阀cartridge valve滑阀slide valve锥阀poppet valve阀芯valve element阀芯位置valve element position单向阀check valve液控单向阀pilot-controlled check valve 梭阀shuttle valve压力控制阀pressure relief valve溢流阀pressure relief valve顺序阀sequence valve减压阀pressure reducing valve平衡阀counterbalance valve卸荷阀unloading valve直动式directly operated type先导式pilot-operated type机械控制式mechanically controlled type 手动式manually operated type液控式hydraulic controlled type流量控制阀flow control valve固定节流阀fixed restrictive valve可调节流阀adjustable restrictive valve 单向节流阀one-way restrictive valve调速阀speed regulator valve分流阀flow divider valve集流阀flow-combining valve截止阀shut-off valve球阀global(ball)valve针阀needle valve闸阀gate valve膜片阀diaphragm valve蝶阀butterfly valve噪声等级noise level放大器amplifier模拟放大器analogue amplifier数字放大器digital amplifier传感器sensor阈值threshold接头fitting；connection焊接式接头welded fitting扩口式接头flared fitting快换接头quick release coupling 法兰接头flange connection弯头elbow异径接头reducer fitting流道flow pass油口port闭式油箱sealed reservoir油箱容量reservoir fluid capacity 气囊式蓄能器bladder accumulator 空气污染air contamination固体颗粒污染solid contamination 液体污染liquid contamination空气过滤器air filter油雾气lubricator热交换器heat exchanger冷却器cooler加热器heater温度控制器thermostat消声器silencer双筒过滤器duplex filter过滤器压降filter pressure drop有效过滤面积effective filtration area 公称过滤精度nominal filtration rating 压溃压力collapse pressure填料密封packing seal机械密封mechanical seal径向密封radial seal旋转密封rotary seal活塞密封piston seal活塞杆密封rod seal防尘圈密封wiper seal；scraper组合垫圈bonded washer复合密封件composite seal弹性密封件elastomer seal丁腈橡胶nitrile butadiene rubber；NBR 聚四氟乙烯polytetrafluoroethene；PTFE 优先控制override control压力表pressure gauge压力传感器electrical pressure transducer 压差计differential pressure instrument 液位计liquid level measuring instrument 流量计flow meter压力开关pressure switch脉冲发生器pulse generator液压泵站power station空气处理单元air conditioner unit压力控制回路pressure control circuit安全回路safety circuit差动回路differential circuit调速回路flow control circuit进口节流回路meter-in circuit出口节流回路meter-out circuit同步回路synchronizing circuit开式回路open circuit闭式回路closed circuit管路布置pipe-work管卡clamper联轴器drive shaft coupling操作台control console控制屏control panel避震喉compensator粘度viscosity运动粘度kinematic viscosity密度density含水量water content闪点flash point防锈性rust protection抗腐蚀性anti-corrosive quality便携式颗粒检测仪portable particle counter 电磁阀Solenoid valve单向阀Check valve插装阀Cartridge valve叠加阀Sandwich plate valve先导阀Pilot valve液控单向阀Pilot operated check valve板式安装Sub-plate mount集成块Manifold block压力溢流阀Pressure relief valve流量阀Flow valve节流阀Throttle valve双单向节流阀Double throttle check valve 旋钮Rotary knob节流板Rectifier plate伺服阀Servo valve比例阀Proportional valve位置反馈Position feedback渐增流量Progressive flow电磁铁释放De-energizing of solenoid 二、介质类磷酸甘油酯Phosphate ester(HFD-R)水-乙二醇Water-glycol(HFC)乳化液Emulsion缓蚀剂Inhibitor合成油Synthetic lubricating oil三、液压安装工程污染Contamination灌浆Grout失效Failure点动Jog爬行Creep摩擦Abrasion(活塞杆)伸出Retract(活塞杆)缩回Extension误动作Malfunction酸洗Pickling冲洗Flushing槽式酸洗Dipping process循环Re-circulation钝化Passivity柠檬酸Nitric acid氩气Argon对接焊Butt welding套管焊Socket welding惰性气体焊Inert gas welding 四、管接头Bite type fittings卡套式管接头Tube to tube fittings接管接头union直通接管接头union elbow直角管接头union tee三通管接头union cross四通管接头Mal stud fittings端直通管接头Bulkhead fittings长直通管接头Weld fittings焊接式管接头Female connector fittings接头螺母Reducers extenders变径管接头Banjo fittings铰接式管接头Adjustable fittings/swivel nut旋转接头五、伺服阀及伺服系统性能参数Dynamic response动态频响DDV-direct drive valve直动式伺服阀NFPA-National Fluid Power Association美国流体控制学会Phase lag相位滞后Nozzle flapper valve喷嘴挡板阀Servo-jet pilot valve射流管阀Dither颤振电流Coil impedance线圈阻抗Flow saturation流量饱和Linearity线形度Symmetry对称性Hysterics滞环Threshold灵敏度Lap滞后Pressure gain压力增益Null零位Null bias零偏Null shift零飘Frequency response频率响应Slope曲线斜坡液压系统(hydraulic system)执行元件(actuator)液压缸(cylinder)液压马达(motor)液压回路(circuit)压力控制回路(pressure control)流量(速度)控制回路(speed control)方向控制回路(directional valve control)安全回路(security control)定位回路(position control)同步回路(synchronise circuit)顺序动作回路(sequeunt circuit)液压泵(pump)阀(valve)压力控制阀(pressure valve)流量控制阀(flow valve)方向控制阀(directional valve)液压辅件(accessory)普通阀(common valve)插装阀(cartridge valve)叠加阀(superimposed valve)文章链接：中国化工仪器网/tech_news/Detail/269585.html。
液压英文文献及翻译液压系统1.绪论液压站称液压泵站，是独立的液压装置。
它是按逐级要求供油。
并控制液压油流方向、压力和流量，适用在主机与液压装置可分离的各种液压机械上面。
用户在购后只要将液压站与主机上执行机构（油缸或油马达）用不同的油管相连，液压机械即实现各种规定的动作与工作循环。
液压站是由集成块、泵装置或阀组合、电气盒、油箱电气盒组合而成。
各个部件功能为：泵装置——上装有电机和油泵，其是液压站的动力源，能将机械能转化为液压油压力能。
阀组合－－其板式阀装在立板上，板后管连接，与集成块的功能相同。
油集成块－－是由液压阀及通道体组装而成。
其对液压油实行压力、方向和流量调节。
箱－－是板焊的半封闭容器，上面还装有滤油网、空气滤清器等，是用来储油与油的冷却及过滤。
电气盒－－分两种型式：一种是设置外接引线的端子板；一种是配置了全套控制电器。
液压站工作原理：电机带动油泵转动，然后泵从油箱中吸油并供油，将机械能转化为液压站压力能，液压油通过集成块（或阀组合）实现方向、压力、流量调节后经过外接管路并至液压机械里的油缸或油马达中，从而控制液动机方向变换、力量的大小及速度的快慢，来推动各种液压机械做功。
(1)液压的发展历程在我国液压（含液力，下同）、气动和密封件工业的发展历程，大致可分成三个阶段，即：在20世纪50年代初到60年代初是起步阶段；60-70年代为专业化生产体系的成长阶段；80-90年代为快速发展阶段。
在其中，液压工业始于50年代初从机床行业生产的仿苏的磨床、拉床、仿形车床等液压传动来起步，液压元件由机床厂里的液压车间生产，自产自用。
在进入60年代后，液压技术应用从机床逐渐推广到农业机械与工程机械等领域，原来附属于主机厂里的液压车间有些独立出来，成为液压件的专业生产厂。
在60年代末、70年代初，随着生产机械化的不断发展，特别是在为第二汽车制造厂等提供了高效、自动化设备的带动下，液压元件制造业出现了不断迅速发展的局面，一批中小企业也开始成为液压件专业制造厂。
附录Hydraulic SystemHydraulic presser drive and air pressure drive hydraulic fluid as the transmission is made according to the 17th century, Pascal's principle of hydrostatic pressure to drive the development of an emerging technology, the United Kingdom in 1795 •Barman Joseph (Joseph Barman, 1749-1814), in London water as a medium to form hydraulic press used in industry, the birth of the world's first hydraulic press. Media work in 1905 will be replaced by oil-water and further improved.After the World War I (1914-1918) ,because of the extensive application of hydraulic transmission, especially after 1920, more rapid development. Hydraulic components in the late 19th century about the early 20th century, 20 years, only started to enter the formal phase of industrial production. 1925 Vickers (F. Vickers) the invention of the pressure balanced vane pump, hydraulic components for the modern industrial or hydraulic transmission of the gradual establishment of the foundation. The early 20th century G • Constantia scofluctuations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic trans- mission (hydraulic coupling, hydraulic torque converter, etc.) contributions, so that these two areas of development.The Second World War (1941-1945) period, in the United States 30% of machine tool applications in the hydraulic transmission. It should be noted that the development of hydraulic transmission in Japan than Europe and the United States and other countries fornearly 20 years later. Before and after in 1955, the rapid development of Japan's hydraulic drive, set up in 1956, "Hydraulic Industry." Nearly 20 to 30 years, the development of Japan's fast hydraulic transmission, a world leader.Hydraulic transmission There are many outstanding advantages, it is widely used, such as general industrial use of plastics processing machinery, the pressure of machinery, machine tools, etc.; operating machinery engineering machinery, construction machinery, agricultural machinery, automobiles, etc.; iron and steel industry metallurgical machinery, lifting equipment, such as roller adjustment device; civil water projects with flood control and dam gate devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship from the deck heavy machinery (winch), the bow doors, bulkhead valve, stern thruster, etc.; special antenna technology giant with control devices, measurement buoys, movements such as rotating stage; military-industrial control devices used in artillery, ship anti- rolling devices, aircraft simulation, aircraft retractable landing gear and rudder control devices and other devices.A complete hydraulic system consists of five parts, namely, power components, the implementation of components, control components, auxiliary components and hydraulic oil.The role of dynamic components of the original motive fluid into mechanical energy to the pressure that the hydraulic system of pumps, it is to power the entire hydraulic system. The structure of the form of hydra- ulic pump gears are generally pump, vane pump and piston pump.Implementation of components (such as hydraulic cylinders and hydraulic motors) which isthe pressure of the liquid can be converted to mechanical energy to drive the load for a straight line reciprocating movement or rotational movement.Control components (that is, the various hydraulic valves) in the hydraulic system to control and regulate the pressure of liquid, flow rate and direction. According to the different control functions, hydraulic pressure control valve can be divided into valves, flow control valves and directional control valve. Pressure control valves are divided into benefits flow valve (safety valve), pressure relief valve, sequence valve, pressure relays, etc.; flow control valves including throttle, adjusting the valves, flow diversion valve sets, etc.; directional control valve includes a one-way valve , one-way fluid control valve, shuttle valve, valve and so on. Under the control of different ways, can be divided into the hydraulic valve control switch valve, control valve and set the value of the ratio control valve.Auxiliary components, including fuel tanks, oil filters, tubing and pipe joints, seals, pressure gauge, oil level, such as oil dollars.Hydraulic oil in the hydraulic system is the work of the energy transfer medium, there are a variety of mineral oil, emulsion oil hydraulic molding Hop categories.The role of the hydraulic system is to help humanity work. Mainly by the implementation of components to rotate or pressure into a reciprocating motion.Hydraulic system and hydraulic power control signal is composed of two parts, the signal control of some parts of the hydraulic power used to drive the control valve movement.Part of the hydraulic power means that the circuit diagram used to show the differentfunctions of the interrelationship between components. Containing the source of hydraulic pump, hydraulic motor and auxiliary components; hydraulic control part contains a variety of control valves, used to control the flow of oil, pressure and direction; operative or hydraulic cylinder with hydraulic motors, according to the actual requirements of their choice.In the analysis and design of the actual task, the general block diagram shows the actual operation of equipment. Hollow arrow indicates the signal flow, while the solid arrows that energy flow.Basic hydraulic circuit of the action sequence - Control components (two four-way valve) and the spring to reset for the implementation of components (double-acting hydraulic cylinder), as well as the extending and retracting the relief valve opened and closed. For the implementation of components and control components, presentations are based on the corresponding circuit diagram symbols, it also introduced ready made circuit diagram symbols.Working principle of the system, you can turn on all circuits to code. If the first implementation of components numbered 0, the control components associated with the identifier is 1. Out with the implementation of components corresponding to the identifier for the even components, then retracting and implementation of components corresponding to the identifier for the odd components. Hydraulic circuit carried out not only to deal with numbers, but also to deal with the actual device ID, in order to detect system failures.DIN ISO1219-2 standard definition of the number of component composition, which includes the following four parts: device ID, circuit ID, component ID and component ID.The entire system if only one device, device number may be omitted.Practice, another way is to code all of the hydraulic system components for numbers at this time, components and component code should be consistent with the list of numbers. This method is particularly applicable to complex hydraulic control system, each control loop are the corresponding number with the systemWith mechanical transmission, electrical transmission compared to the hydraulic drive has the following advantages:1. a variety of hydraulic components can easily and flexibly to layout.2. light weight, small size, small inertia, fast response.3. to facilitate manipulation of control, enabling a wide range of stepless speed regulation (speed range of 2000:1).4. to achieve overload protection automatically.5. the general use of mineral oil as a working medium, the relative motion can be self-lubricating surface, long service life;6. it is easy to achieve linear motion .7. it is easy to achieve the automation of machines, when the joint control of the use of electro-hydraulic, not only can achieve a higher degree of process automation, and remote control can be achieved.The shortcomings of the hydraulic system:1. as a result of the resistance to fluid flow and leakage of the larger, so less efficient. If not handled properly, leakage is not only contaminated sites, but also may cause fire and explosion.2. vulnerable performance as a result of the impact of temperature change, it would be inappropriate in the high or low temperature conditions.3. the manufacture of precision hydraulic components require a higher, more expensive and hence the price.4. due to the leakage of liquid medium and the compressibility and can not be strictly the transmission ratio.5. hydraulic transmission is not easy to find out the reasons for failure; the use and maintenance requirements for a higher level of technology.In the hydraulic system and its system, the sealing device to prevent leakage of the work of media within and outside the dust and the intrusion of foreign bodies. Seals played the role of components, namely seals. Medium will result in leakage of waste, pollution and environmental machinery and even give rise to malfunctioning machinery and equipment for personal accident. Leakage within the hydraulic system will cause a sharp drop in volumetric efficiency, amounting to less than the required pressure, can not even work. Micro-invasive system of dust particles, can cause or exacerbate friction hydraulic component wear, and further lead to leakage.Therefore, seals and sealing device is an important hydraulic equipment components. The reliability of its work and life, is a measure of the hydraulic system an important indicator of good or bad. In addition to the closed space, are the use of seals, so that two adjacent coupling surface of the gap between the need to control the liquid can be sealed following the smallest gap. In the contact seal, pressed into self-seal-style and self-styled self-tight seal (ie, sealed lips) two.The three hydraulic system diseases1. as a result of heat transmission medium (hydraulic oil) in the flow velocity in various parts of the existence of different, resulting in the existence of a liquid within the internal friction of liquids and pipelines at the same time there is friction between the inner wall, which are a result of hydraulic the reasons for the oil temperature. Temperature will lead to increased internal and external leakage, reducing its mechanical efficiency. At the same time as a result of high temperature, hydraulic oil expansion will occur, resulting in increased com- pression, so that action can not be very good control of transmission. Solution: heat is the inherent characteristics of the hydraulic system, not only to minimize eradication. Use a good quality hydraulic oil, hydraulic piping arrangement should be avoided as far as possible the emergence of bend, the use of high-quality pipe and fittings, hydraulic valves, etc.2. the vibration of the vibration of the hydraulic system is also one of its malaise. As a result of hydraulic oil in the pipeline flow of high-speed impact and the control valve to open the closure of the impact of the process are the reasons for the vibration system. Strong vibration control action will cause the system to error, the system will also be some of the more sophisticated equipment error, resulting in system failures. Solutions: hydraulic pipe should be fixed to avoid sharp bends. To avoid frequent changes in flow direction, can not avoid damping measures should be doing a good job. The entire hydraulic system should have a good damping measures, while avoiding the external local oscillator on the system.3. the leakage of the hydraulic system leak into inside and outside the leakage. Leakagerefers to the process with the leak occurred in the system, such as hydraulic piston-cylinder on both sides of the leakage, the control valve spool and valve body, such as between the leakage. Although no internal leakage of hydra- ulic fluid loss, but due to leakage, the control of the established movements may be affected until the cause system failures. Outside means the occurrence of leakage in the system and the leakage between the external environment. Direct leakage of hydraulic oil into the environment, in addition to the system will affect the working environment, not enough pressure will cause the system to trigger a fault. Leakage into the environment of the hydraulic oil was also the danger of fire. Solution: the use of better quality seals to improve the machining accuracy of equipment.Another: the hydraulic system for the three diseases, it was summed up: "fever, with a father拉稀" (This is the summary of the northeast people). Hydraulic system for the lifts, excavators, pumping station, dynamic, crane, and so on large-scale industry, construction, factories, enterprises, as well as elevators, lifting platforms, Deng Axle industry and so on.Hydraulic components will be high-performance, high-quality, high reliability, the system sets the direction of development; to the low power, low noise, vibration, without leakage, as well as pollution control, water-based media applications to adapt to environmental requirements, such as the direction of development; the development of highly integrated high power density, intelligence, macaronis and micro-light mini-hydraulic components; active use of new techniques, new materials and electronics, sensing and other high-tech.---- Hydraulic coupling to high-speed high-power and integrated development of hydraulic transmission equipment, development of water hydraulic coupling medium speedand the field of automotive applications to develop hydraulic reducer, improve product reliability and working hours MTBF; hydraulic torque converter to the development of high-power products, parts and components to improve the manufacturing process technology to improve reliability, promote computer-aided technology, the development of hydraulic torque converter and power shift transmission technology supporting the use of ; Clutch fluid viscosity should increase the quality of products, the formation of bulk to the high-power and high-speed direction.Pneumatic Industry:---- Products to small size, light weight, low power consumption, integrated portfolio of development, the implementation of the various types of components, compact structure, high positioning accuracy of the direction of development; pneumatic components and electronic technology, to the intelligent direction of development; component performance to high-speed, high-frequency, high-response, high-life, high temp- erature, high voltage direction, commonly used oil-free lubrication, application of new technology, new technology and new materials.1. Used high-pressure hydraulic components and the pressure of continuous work to reach 40Mpa, the maximum pressure to achieve instant 48Mpa;2. Diversification of regulation and control;3. To further improve the regulation performance, increase the efficiency of the power train;4. Development and mechanical, hydraulic, power transmission of the composite portfolio adjustment gear;5. Development of energy saving, energy efficient system function;6. To further reduce the noise;7. Application of Hydraulic Cartridge Valves thread technology, compact structure, to reduce the oil spill.液压系统液压传动和气压传动称为流体传动，是根据17世纪帕斯卡提出的液体静压力传动原理而发展起来的一门新兴技术，1795年英国约瑟夫•布拉曼(Joseph Braman,1749-1814)，在伦敦用水作为工作介质，以水压机的形式将其应用于工业上，诞生了世界上第一台水压机。
附件1：外文资料翻译译文流体传动流体传动包括气体(压)传动和液体传动，液体传动分为液压传动、液力传动和液粘传动。
液压传动基于帕卡定律，以液体的压能来传递动力；液力传动基于欧拉方程，以液体动量短的变化来传递动力；液粘传动基于牛顿内摩擦定律，以液体的粘性来传递动力。
液力传动的基本元件是液力偶合器和液力变矩器。
液力偶合器的基本构件是具有若干径向平面叶片的、构成工作腔的泵轮和涡轮。
液力传动油在工作腔里高速循环流动传递动力，油液随从泵轮做牵连运动的同时因受离心力作用而做离心运动，从泵轮(及输入轴)吸收机械能并转化为动量矩(mVR)增量，高速液流从泵轮冲入涡轮做向心流动释放动量矩，推动涡轮(及输出轴)旋转，带动工作机(及负载)做功。
液力变矩器的基本构件是泵轮、涡轮和导轮，它们均是具有空间(弯曲)叶片的工作轮，按相关顺序排列构成工作腔。
液力传动油在工作腔中被泵轮涡轮搅动，使液流获得动量矩增量，经过导轮调转液流方向后冲入涡轮，释放动量矩(动能)推动涡轮带动工作机旋转做功。
我国液力元件近年发展较快，2003 年液力偶合器的全国年产量约7 万台。
广泛应用于带式输送机、刮板输送机、球磨机、风机、压缩机、水泵和油泵等设备的传动中，提高传动品质并节约能源。
当前我国液力偶合器的最高输出转速为6500r/min，最小功率为0.3kW，最大功率为7100kW。
液力偶合器的发展趋势是高转速、大功率。
国际上液力偶合器产品以德国福依特公司最为著名，据资料称已有转速达20000r/min、功率达55000kW 的产品，可见我国与之尚有相当大的差距。
当然，功率大的液力元件对液力传动油的要求较高。
液力变矩器主要用于工程机械、石油机械和内燃机车。
液力变矩器主要与内燃机匹配应用，其转速范围在2000 ～3000r/min。
工程机械应用较多，最大功率700HP 左右，年产量约7 万台。
石油机械应用较少，功率达1500HP。
内燃机车应用更少，功率高达3000HP。
第六章液压动力源：油泵（The Source of Hydraulic Power: Pumps）6.1概述（INTRODUCTION）一个油泵是液压系统的心脏，它将机械能转变为压力能。
机械能是通过像电机这样的原动机输送给油泵的。
由于机械作用，油泵在其进油口产生局部真空。
油液在大气压力的作用下通过进油口进入油泵内部。
油泵再推动油液进入液压系统（A pump, which is the heart of a hydraulic system, converts mechanical energy into hydraulic energy. The mechanical energy is delivered to the pump via a prime mover such as an electric motor. Due to mechanical action, the pump creates a partial vacuum at its inlet. This permits atmospheric pressure to force the fluid through the inlet line and into thepump. The pump then pushes the fluid into the hydraulic system）。
油泵根据液压功率的产生主要分为两大类（There are two broad classifications of pumps as identified by the fluid power industry）：1.非容积泵（Nonpositive displacement pumps）：这种类型经常用于低压，大流量的场合。
因为它们不能够承受高压，在液压传动中很少使用。
通常它们的最高压力被限制在1.7～2.1MPa。
这种类型的油泵一般用于将液体从一个地方输送到另一个地方（This type is generally used for low-pressure, high-volume flow applications. Because they are not capable of withstanding high pressure, they are of little use in the fluid power field. Normally their maximum pressure capacity is limited to 1.7～2.1MPa. This type of pump isprimarily used for transporting fluids from one location to another）。
外文文献翻译(含：英文原文及中文译文)英文原文Hydraulic systemW Arnold1 IntroductionThe hydraulic station is called a hydraulic pump station and is an independent hydraulic device. It is step by step to supply oil. And control the direction of hydraulic oil flow, pressure and flow, suitable for the host and hydraulic equipment can be separated on the various hydraulic machinery.After the purchase, the user only needs to connect the hydraulic station and the actuator (hydraulic or oil motor) on the mainframe with different tubings. The hydraulic machine can realize various specified actions and working cycles.The hydraulic station is a combination of manifolds, pump units or valve assemblies, electrical boxes, and tank electrical boxes. Each part function is:The pump unit is equipped with a motor and an oil pump, which is the power source of the hydraulic station and can convert mechanical energy into hydraulic oil pressure energy.V alve combination - its plate valve is mounted on the vertical plate, and the rear plate is connected with the same function as the manifold.Oil manifolds - assembled from hydraulic valves and channel bodies. It regulates hydraulic oil pressure, direction and flow.Box--a semi-closed container for plate welding. It is also equipped with an oil screen, an air filter, etc., which is used for cooling and filtering of oil and oil.Electrical box - divided into two types: one is to set the external lead terminal board; one is equipped with a full set of control appliances.The working principle of the hydraulic station: The motor drives the oil pump to rotate, then the pump sucks oil from the oil tank and supplies oil, converts the mechanical energy into hydraulic pressure energy, and the hydraulic oil passes through the manifold (or valve assembly) to adjust the direction, pressure and flow and then passes through the external tube. The way to the hydraulic cylinder or oil motor in the hydraulic machinery, so as to control the direction of the hydraulic motor, the strength of the speed and speed, to promote all kinds of hydraulic machinery to do work.(1) Development history of hydraulic pressureThe development history of hydraulics (including hydraulic power, the same below), pneumatics, and seals industry in China can be roughly divided into three stages, namely: the starting stage in the early 1950s to the early 60s; and the professional in the 60s and 70s. The growth stage of the production system; the 80-90's is a stage of rapid development. Among them, the hydraulic industry began in the early 1950s with thedevelopment of hydraulic machines such as Grinding Machines, broaching machines, and profiling lathes, which were produced by the machine tool industry. The hydraulic components were produced by the hydraulic workshop in the machine tool factory, and were produced for self use. After entering the 1960s, the application of hydraulic technology was gradually promoted from the machine tool to the agricultural machinery and engineering machinery. The original hydraulic workshop attached to the main engine plant was independent and became a professional manufacturer of hydraulic components. In the late 1960s and early 1970s, with the continuous development of mechanization of production, particularly in the provision of highly efficient and automated equipment for the second automobile manufacturing plant, the hydraulic component manufacturing industry witnessed rapid development. The batch of small and medium-sized enterprises also began to become specialized manufacturers of hydraulic parts. In 1968, the annual output of hydraulic components in China was close to 200,000 pieces. In 1973, in the fields of machine tools, agricultural machinery, construction machinery and other industries, the professional factory for the production of hydraulic parts has grown to over 100, and its annual output exceeds 1 million pieces. Such an independent hydraulic component manufacturing industry has taken shape. At this time, the hydraulic product has evolved from the original imitation Su product intoa combination of imported technology and self-designed products. The pressure has been developed towards medium and high pressures, and electro-hydraulic servo valves and systems have been developed. The application of hydraulics has been further expanded. The pneumatic industry started a few years later than hydraulics, and it was only in 1967 that it began to establish a professional pneumatic components factory. Pneumatic components began to be manufactured and sold as commodities. Its sealing industry including rubber seals, flexible graphite seals, and mechanical seals started from the production of common O-rings, oil seals, and other extruded rubber seals and asbestos seal products in the early 1950s. In the early 1960s, it began to develop and produce flexible products. Graphite seals and mechanical seals and other products. In the 1970s, a batch of batches of professional production plants began to be established one after another in the systems of the former Ministry of Combustion, the Ministry of Agriculture, and the Ministry of Agricultural Machinery, formally forming the industry, which laid the foundation for the development of the seal industry.In the 1980s, under the guidance of the national policy of reform and opening up, with the continuous development of the machinery industry, the contradiction between the basic components lags behind the host computer has become increasingly prominent and caused the attention of all relevant departments. To this end, the former Ministry of Machinesestablished the General Infrastructure Industry Bureau in 1982, and unified the original pneumatic, hydraulic, and seal specialties that were scattered in the industries of machine tools, agricultural machinery, and construction machinery, etc. The management of a piece of office, so that the industry in the planning, investment, the introduction of technology and scientific research and development and other aspects of the basic parts of the bureau's guidance and support. This has entered a period of rapid development, it has introduced more than 60 foreign advanced technology, of which more than 40 hydraulic, pneumatic 7, after digestion and absorption and technological transformation, are now mass production, and has become the industry's leading products . In recent years, the industry has intensified its technological transformation. From 1991 to 1998, the total investment of national, local, and corporate self-raised funds totaled about 2 billion yuan, of which more than 1.6 billion were hydraulic. After continuous technological transformation and technological breakthroughs, the technical level of a group of major enterprises has been further improved, and technological equipment has also been greatly improved, laying a good foundation for forming a high starting point, specialization, and mass production. In recent years, under the guidance of the principle of common development of multiple ownership systems in the country, various small and medium-sized enterprises with different ownership have rapidly emerged and haveshown great vitality. With the further opening up of the country, foreign-funded enterprises have developed rapidly, which plays an important role in raising industry standards and expanding exports. So far China has established joint ventures with famous manufacturers in the United States, Germany, Japan and other countries or directly established piston pumps/motors, planetary speed reducers, hydraulic control valves, steering gears, hydraulic systems, hydrostatic transmissions, and hydraulic components. The company has more than 50 manufacturing enterprises such as castings, pneumatic control valves, cylinders, gas processing triplets, rubber seals, and mechanical seals, and has attracted more than 200 million U.S. dollars in foreign capital.(2) Current statusBasic profileAfter more than 40 years of hard work, China's hydraulics, pneumatics and seals industry has formed a complete industrial system with a certain level of production capacity and technical level. According to the statistics of the third n ational industrial census in 1995, China’s state-owned, privately-owned, cooperative, village-run, individual, and “funded enterprises” have annual sales income of more than 1 million yuan in hydraulic, pneumatic, and seal industrial townships and above. There are a total of more than 1,300 companies, including about 700 hydraulics, and about 300 pneumatic and sealing parts. According to thestatistics of the international industry in 1996, the total output value of the hydraulic industry in China was about 2.448 billion yuan, accounting for the 6th in the world; the total output value of the pneumatic industry was about 419 million yuan, accounting for the world’s10 people.2. Current supply and demand profileWith the introduction of technology, independent development and technological transformation, the technical level of the first batch of high-pressure plunger pumps, vane pumps, gear pumps, general hydraulic valves, oil cylinders, oil-free pneumatic components and various types of seals has become remarkable. Improve, and can be stable mass production, provide guarantees for all types of host to improve product quality. In addition, certain achievements have also been made in the aspects of CAD, pollution control, and proportional servo technology for hydraulic pneumatic components and systems, and have been used for production. So far, the hydraulic, pneumatic and seal products have a total of about 3,000 varieties and more than 23,000 specifications. Among them, there are about 1,200 types of hydraulic pressure, more than 10,000 specifications (including 60 types of hydrodynamic products, 500 specifications); about 1350 types of pneumatic, more than 8,000 specifications; there are also 350 types of rubber seals, more than 5000 The specifications are now basically able to adapt to the general needs ofvarious types of mainframe products. The matching rate for major equipment sets can reach more than 60%, and a small amount of exports has started.In 1998, the domestic production of hydraulic components was 4.8 million pieces, with sales of about 2.8 billion yuan (of which mechanical systems accounted for 70%); output of pneumatic components was 3.6 million pieces, and sales were about 550 million yuan (including mechanical systems accounting for about 60%) The production of seals is about 800 million pieces, and the sales volume is about 1 billion yuan (including about 50% of mechanical systems). According to the statistics of the annual report of the China Hydraulic and Pneumatic Sealing Industry Association in 1998, the production and sales rate of hydraulic products was 97.5% (101% of hydraulic power), 95.9% of air pressure, and 98.7% of seal. This fully reflects the basic convergence of production and sales.Although China's hydraulic, pneumatic and sealing industries have made great progress, there are still many gaps compared with the development needs of the mainframe and the world's advanced level, which are mainly reflected in the variety, performance and reliability of products. . Take hydraulic products as an example, the product varieties are only 1/3 of the foreign country, and the life expectancy is 1/2 of that of foreign countries. In order to meet the needs of key hosts, imported hosts, and majortechnical equipment, China has a large number of imported hydraulic, pneumatic, and sealing products every year. According to customs statistics and relevant data analysis, in 1998, the import volume of hydraulic, pneumatic and seal products was about 200 million U.S. dollars, of which the hydraulic pressure was about 140 million U.S. dollars, the pneumatics were 30 million U.S. dollars, and the seal was about 0.3 billion U.S. dollars. The year is slightly lower. In terms of amount, the current domestic market share of imported products is about 30%. In 1998, the total demand for hydraulic parts in the domestic market was about 6 million pieces, and the total sales volume was 4 billion yuan; the total demand for pneumatic parts was about 5 million pieces, and the total sales volume was over 700 million yuan; the total demand for seals was about 1.1 billion yuan. Pieces, total sales of about 1.3 billion yuan. (3) Future developments1. The main factors affecting development(1) The company's product development capability is not strong, and the level and speed of technology development can not fully meet the current needs for advanced mainframe products, major technical equipment and imported equipment and maintenance;(2) Many companies have lagged behind in manufacturing process, equipment level and management level, and their sense of quality is not strong, resulting in low level of product performance, unstable quality,poor reliability, and insufficiency of service, and lack of user satisfaction. And trusted branded products;(3) The degree of professional specialization in the industry is low, the power is scattered, the duplication of the low level is serious, the product convergence between the region and the enterprise leads to blind competition, and the prices are reduced each other, thus the efficiency of the enterprise is reduced, the funds are lacking, and the turnover is difficult. Insufficient investment in development and technological transformation has severely restricted the overall level of the industry and its competitive strength.(4) When the degree of internationalization of the domestic market is increasing, foreign companies have gradually entered the Chinese market to participate in competition, coupled with the rise of domestic private, cooperative, foreign-funded, and individual enterprises, resulting in increasing impact on state-owned enterprises. .2. Development trendWith the continuous deepening of the socialist market economy, the relationship between supply and demand in the hydraulic, pneumatic and sealed products has undergone major changes. The seller market characterized by “shortage” has basically become a buyer’s market characterized by “structured surplus”. Replaced by. From the perspective of overall capacity, it is already in a trend of oversupply, and in particular,general low-grade hydraulic, pneumatic and seals are generally oversupply; and like high-tech products with high technological content and high value and high value-added products that are urgently needed by the host, Can not meet the needs of the market, can only rely on imports. After China's entry into the WTO, its impact may be greater. Therefore, during the “10th Five-Y ear Plan” period, the growth of the industry’s output value must not only rely on the growth of quantity. Instead, it should focus on the structural contradiction of the industry and intensify efforts to adjust the industrial structure and product structure. It should be based on the improvement of quality. Product technology upgrades in order to adapt to and stimulate market demand, and seek greater development.2. Hydraulic application on power slide(1) Introduction of Power Sliding TableUsing the binding force curve diagram and the state space analysis method to analyze and study the sliding effect and the smoothness of the sliding table of the combined machine tool, the dynamics of the hydraulic drive system of the sliding table—the self-regulating back pressure regulating system are established. mathematical model. Through the digital simulation system of the computer, the causes and main influencing factors of the slide impact and the motion instability are analyzed. What kind of conclusions can be drawn from those, if we canreasonably design the structural dimensions of hydraulic cylinders and self-regulating back pressure regulators ——The symbols used in the text are as follows:s 1 - flow source, that is, the flow rate of the governor valve outlet;S el —— sliding friction of the sliding table;R - the equivalent viscous friction coefficient of the slide;I 1 - quality of slides and cylinders;12 - self-adjusting back pressure valve core quality;C 1, c 2 - liquid volume without cylinder chamber and rod chamber;C 2 - Self-adjusting back pressure valve spring compliance;R 1, R2 - Self-adjusting back pressure valve damping orifice fluid resistance;R 9 - Self-adjusting back pressure valve valve fluid resistance;S e2——initial pre-tightening force of self-adjusting back pressure valve spring;I 4, I5 - Equivalent liquid sense of the pipeline;C 5, C 6 - equivalent liquid capacity of the pipeline;R 5, R7 - Equivalent liquid resistance of the pipeline;V 3, V4 - cylinder rodless cavity and rod cavity volume;P 3, P4—pressure of the rodless cavity and rod cavity of the cylinder;F - the slide bears the load;V - speed of slide motion;In this paper, the power bond diagram and the state space splitting method are used to establish the system's motion mathematical model, and the dynamic characteristics of the slide table can be significantly improved.In the normal operation of the combined machine tool, the magnitude of the speed of the slide, its direction and the load changes it undergoes will affect its performance in varying degrees. Especially in the process of work-in-process, the unsteady movement caused by the advancing of the load on the slide table and the cyclical change of the load will affect the surface quality of the workpiece to be machined. In severe cases, the tool will break. According to the requirements of the Dalian Machine Tool Plant, the author used the binding force curve diagram and the state space analysis method to establish a dynamic mathematical model of a self-adjusting back pressure and speed adjustment system for the new hydraulic drive system of the combined machine tool slide. In order to improve the dynamic characteristics of the sliding table, it is necessary to analyze the causes and main influencing factors of the impetus and movement of the sliding table. However, it must pass the computer's digital simulation and the final results obtained from the research.(2) Dynamic Mathematical ModelThe working principle diagram of the self-adjusting back pressure speedregulation system of the combined machine tool slide hydraulic drive system is shown in the figure. This system is used to complete the work-cycle-stop-rewind. When the sliding table is working, the three-position four-way reversing valve is in the illustrated position. The oil supply pressure of the oil pump will remain approximately constant under the effective action of the overflow valve, and the oil flow passes through the reversing valve and adjusts the speed. The valve enters the rodless chamber of the cylinder to push the slide forward. At the same time, the pressurized oil discharged from the rod chamber of the cylinder will flow back to the tank through the self-regulating back pressure valve and the reversing valve. During this process, there was no change in the operating status of both the one-way valve and the relief valve. The complex and nonlinear system of the hydraulic drive system of the self-adjusting back pressure governor system is a kind of self-adjusting back-pressure governor system. To facilitate the study of its dynamic characteristics, a simple and reasonable dynamic mathematical model that only considers the main influencing factors is established. Especially important [1][2]. From the theoretical analysis and the experimental study, we can see that the system process time is much longer than the process time of the speed control valve. When the effective pressure bearing area of the rodless cavity of the fuel tank is large, the flow rate at the outlet of the speed control valve is instantaneous. The overshoot is reflected in thesmall change in speed of the slide motion [2]. In order to further broaden and deeply study the dynamic characteristics of the system so that the research work can be effectively performed on a miniature computer, this article will further simplify the original model [2], assuming that the speed control valve is output during the entire system pass. When the flow is constant, this is considered to be the source of the flow. The schematic diagram of the dynamic model structure of this system is shown in Fig. 2. It consists of a cylinder, a sliding table, a self-adjusting back pressure valve, and a connecting pipe.The power bond graph is a power flow graph. It is based on the transmission mode of the system energy, based on the actual structure, and uses the centralized parameters to represent the role of the subsystems abstractly as a resistive element R, a perceptual element I, and a capacitive element. Three kinds of role of C. Using this method, the physical concept of modeling is clear, and combined with the state-space analysis method, the linear system can be described and analyzed more accurately. This method is an effective method to study the dynamic characteristics of complex nonlinear systems in the time domain. According to the main characteristics of each component of the self-adjusting back pressure control system and the modeling rules [1], the power bond diagram of the system is obtained. The upper half of each key in the figure represents the power flow. The two variables that makeup the power are the force variables (oil pressure P and force F) and the flow variables (flow q and velocity v). The O node indicates that the system is connected in parallel, and the force variables on each key are equal and the sum of the flow variables is zero; 1 The nodes represent the series connection in the system, the flow variables on each key are equal and the sum of the force variables is Zero. TF denotes a transformer between different energy forms. The TF subscripted letter represents the conversion ratio of the flow variable or the force variable. The short bar on the key indicates the causal relationship between the two variables on the key. The full arrow indicates the control relationship. There are integral or differential relationships between the force and flow variables of the capacitive and perceptual elements in the three types of action elements. Therefore, a complex nonlinear equation of state with nine state variables can be derived from Fig. 3 . In this paper, the research on the dynamic characteristics of the sliding table starts from the two aspects of the slide's hedging and the smoothness of the motion. The fourth-order fixed-length Runge-Kutta is used for digital simulation on the IBM-PC microcomputer.(3) Slide advanceThe swaying phenomenon of the slide table is caused by the sudden disappearance of the load acting on the slide table (such as drilling work conditions). In this process, the table load F, the moving speed V, and thepressure in the two chambers of the cylinder P3 and P4 can be seen from the simulation results in Fig. 4. When the sliding table moves at a uniform speed under the load, the oil pressure in the rodless cavity of the oil cylinder is high, and a large amount of energy is accumulated in the oil. When the load suddenly disappears, the oil pressure of the cavity is rapidly reduced, and the oil is rapidly reduced. When the high-pressure state is transferred to the low-pressure state, a lot of energy is released to the system, resulting in a high-speed forward impact of the slide. However, the front slide of the sliding table causes the pressure in the rod cavity of the oil cylinder to cause the back pressure to rise, thereby consuming part of the energy in the system, which has a certain effect on the kicking of the slide table. We should see that in the studied system, the inlet pressure of the self-adjusting back pressure valve is subject to the comprehensive effect of the two-chamber oil pressure of the oil cylinder. When the load suddenly disappears, the pressure of the self-adjusting back pressure valve rapidly rises and stably exceeds the initial back pressure value. It can be seen from the figure that self-adjusting back pressure in the speed control system when the load disappears, the back pressure of the cylinder rises more than the traditional speed control system, so the oil in the rod cavity of the cylinder absorbs more energy, resulting in the amount of forward momentum of the slide It will be about 20% smaller than traditionalspeed control systems. It can be seen from this that the use of self-adjusting back-gear speed control system as a drive system slider has good characteristics in suppressing the forward punch, in which the self-adjusting back pressure valve plays a very large role.(4) The smoothness of the slideWhen the load acting on the slide changes periodically (such as in the case of milling), the speed of the slide will have to fluctuate. In order to ensure the processing quality requirements, it must reduce its speed fluctuation range as much as possible. From the perspective of the convenience of the discussion of the problem, assume that the load changes according to a sine wave law, and the resulting digital simulation results are shown in Figure 5. From this we can see that this system has the same variation rules and very close numerical values as the conventional speed control system. The reason is that when the change of the load is not large, the pressure in the two chambers of the fuel tank will not have a large change, which will eventually lead to the self-regulating back pressure valve not showing its effect clearly.(5) Improvement measuresThe results of the research show that the dynamic performance of a sliding table with self-regulating back pressure control system as a drive system is better than that of a traditional speed control system. To reduce the amount of kick in the slide, it is necessary to rapidly increase the backpressure of the rod cavity when the load disappears. To increase the smoothness of the sliding table, it is necessary to increase the rigidity of the system. The main measure is to reduce the volume of oil. From the system structure, it is known that the cylinder has a large volume between the rod cavity and the oil discharge pipe, as shown in Fig. 6a. Its existence in terms of delay and attenuation of the self-regulating back pressure valve function, on the other hand, also reduces the rigidity of the system, it will limit the further improvement of the propulsion characteristics and the smoothness of the motion. Thus, improving the dynamic characteristics of the sliding table can be handled by two methods: changing the cylinder volume or changing the size of the self-regulating back pressure valve. Through the simulation calculation of the structural parameters of the system and the comparison of the results, it can be concluded that the ratio of the volume V4 between the rod cavity and the oil discharge pipe to the volume V3 between the rodless cavity and the oil inlet pipe is changed from 5.5 to 5.5. At 1 oclock, as shown in the figure, the diameter of the bottom end of the self-adjusting back pressure valve is increased from the original 10mm to 13mm, and the length of the damper triangle groove is reduced from the original lmm to 0.7mm, which will enable the front of the slide table. The impulse is reduced by 30%, the transition time is obviously shortened, and the smoothness of the slide motion will also be greatly improved.中文译文液压系统W Arnold1. 绪论液压站称液压泵站,是独立的液压装置。
Hydraulic SystemThere are only three basic methods of transmitting power: electrical, mechanical, and fluid power. Most applications actually use a combination of the three methods to obtain the most efficient overall system. To properly determine which principle method to use, it is important to know the salient features of each type. For example, fluid systems can transmit power more economically over greater distances than can mechanical types. However, fluid systems are restricted to shorter distances than are electrical systems.Hydraulic power transmission system are concerned with the generation, modulation, and control of pressure and flow, and in general such systems include:1.Pumps which convert available power from the prime mover to hydraulic power at the actuator.2.Valves which control the direction of pump-flow, the level of power produced, and the amount of fluid-flow to the actuators. The power level is determined by controlling both the flow and pressure level.3.Actuators which convert hydraulic power to usable mechanical power output at the point required.4.The medium, which is a liquid, provides rigid transmission and control as well as lubrication of components, sealing in valves, and cooling of the system.5.Connectors which link the various system components, provide power conductors for the fluid under pressure, and fluid flow return to tank (reservoir).6.Fluid storage and conditioning equipment which ensure sufficient quality and quantity as well as cooling of the fluid.Hydraulic systems are used in industrial applications such as stamping presses, steel mills , and general manufacturing , agricultural machines , mining industry , aviation , space technology , deep-sea exploration ,transportation , marinetechnology , and offshore gas petroleum exploration . In short, very few people get through a day of their lives without somehow benefiting from the technology of hydraulics.The secret of hydraulic system’s success and widespread use is its versatility and manageability. Fluid power is not hindered by the geometry of the machine as is the case in mechanical systems. Also, power can be transmitted in almost limitless quantities because fluid systems are not so limited by the physical limitations of materials as are the electrical systems. For example, the performance of an electromagnet is limited by the saturation limit of steel. On the other hand, the power limit of fluid systems is limited only by the strength capacity of the material.Industry is going to depend more and more on automation in order to increase productivity. This includes remote and direct control of production operations, manufacturing processes, and materials handling. Fluid power is the muscle of automation because of advantages in the following four major categories.Ease and accuracy of control. By the use of simple levers and push buttons, the operator of a fluid power systems can readily start, stop, speed up or slow down, and position force which provide any desired horsepower with tolerances as precise as one ten-thousandth of an inch.Multiplication of force. A fluid power system (without using cumbersome gears, pulleys, and levers) can multiply forces simply and efficiently from a fraction of an ounce to several hundred tons of output.Constant force or torque. Only fluid power systems are capable of providing constant force or torque regardless of speed changes. This is accomplished whether the work output moves a few inches per hour, several hundred inches per minute, a few revolutions per hour, or thousands of revolutions per minute.Simplicity, safety, economy. In general, fluid power systems use fewer movingparts than comparable mechanical or electrical systems. Thus, they are simpler to maintain and operate. This, in turn, maximizes safety, compactness, and reliability. For example, a new power steering control designed has made all other kinds of power systems obsolete on many off-highway vehicles. The steering unit consists of a manually operated directional control valve and meter in a single body. Because the sterring unit is fully fluid-linked, mechanical linkages, universal joints, bearings, reduction gears, ect . are eliminated. This provides a simple,compact systems.In addition, very little input torque is required to produce the control needed for the toughest applications. This is important where limitations of control space require a small sterring wheel and it becomes necessary to reduce operator fatigue.Additional benefits of fluid power systems include instantly reversible motion, automatic protection against overloads, and infinitely variable speed control. Fluid power systems also have the highest horsepower per weight ratio of any known power source. In spite of all these highly desirable features of fluid power, it is not a panacea for all power transmission problems. Hydraulic systems also have some drawbacks. Hydraulic oils are messy, and leakage is impossible to completely. Also, most hydraulic oils can cause fires if an oil leak occurs in area of hot equipment. There are only three basic methods of transmitting power: electrical, mechanical, and fluid power. Most applications actually use a combination of the three methods to obtain the most efficient overall system. To properly determine which principle method to use, it is important to know the salient features of each type. For example, fluid systems can transmit power more economically over greater distances than can mechanical types. However, fluid systems are restricted to shorter distances than are electrical systems.Hydraulic power transmission system are concerned with the generation, modulation, and control of pressure and flow, and in general such systems include:Pumps which convert available power from the prime mover to hydraulic power at the actuator.Valves which control the direction of pump-flow, the level of power produced, and the amount of fluid-flow to the actuators. The power level is determined by controlling both the flow and pressure level.Actuators which convert hydraulic power to usable mechanical power output at the point required.The medium, which is a liquid, provides rigid transmission and control as well as lubrication of components, sealing in valves, and cooling of the system.Connectors which link the various system components, provide power conductors for the fluid under pressure, and fluid flow return to tank (reservoir).Fluid storage and conditioning equipment which ensure sufficient quality and quantity as well as cooling of the fluid.Hydraulic systems are used in industrial applications such as stamping presses, steel mills , and general manufacturing , agricultural machines , mining industry , aviation , space technology , deep-sea exploration ,transportation , marine technology , and offshore gas petroleum exploration . In short, very few people get through a day of their lives without somehow benefiting from the technology of hydraulics.The secret of hydraulic system’s success and widespread use is its versatility and manageability. Fluid power is not hindered by the geometry of the machine as is the case in mechanical systems. Also, power can be transmitted in almost limitless quantities because fluid systems are not so limited by the physical limitations of materials as are the electrical systems. For example, the performance of an electromagnet is limited by the saturation limit of steel. On the other hand, the power limit of fluid systems is limited only by the strength capacity of the material.Industry is going to depend more and more on automation in order to increase productivity. This includes remote and direct control of production operations, manufacturing processes, and materials handling. Fluid power is the muscle of automation because of advantages in the following four major categories.1. Ease and accuracy of control. By the use of simple levers and push buttons, the operator of a fluid power systems can readily start, stop, speed up or slow down, and position force which provide any desired horsepower with tolerances as precise as one ten-thousandth of an inch.2. Multiplication of force. A fluid power system (without using cumbersome gears, pulleys, and levers) can multiply forces simply and efficiently from a fraction of an ounce to several hundred tons of output.3. Constant force or torque. Only fluid power systems are capable of providing constant force or torque regardless of speed changes. This is accomplished whether the work output moves a few inches per hour, several hundred inches per minute, a few revolutions per hour, or thousands of revolutions per minute.4. Simplicity, safety, economy. In general, fluid power systems use fewer moving parts than comparable mechanical or electrical systems. Thus, they are simpler to maintain and operate. This, in turn, maximizes safety, compactness, and reliability. For example, a new power steering control designed has made all other kinds of power systems obsolete on many off-highway vehicles. The steering unit consists of a manually operated directional control valve and meter in a single body. Because the sterring unit is fully fluid-linked, mechanical linkages, universal joints, bearings, reduction gears, ect . are eliminated. This provides a simple,compact systems.In addition, very little input torque is required to produce the control needed for the toughest applications. This is important where limitations of controlspace require a small sterring wheel and it becomes necessary to reduce operator fatigue.Additional benefits of fluid power systems include instantly reversible motion, automatic protection against overloads, and infinitely variable speed control. Fluid power systems also have the highest horsepower per weight ratio of any known power source. In spite of all these highly desirable features of fluid power, it is not a panacea for all power transmission problems. Hydraulic systems also have some drawbacks. Hydraulic oils are messy, and leakage is impossible to completely. Also, most hydraulic oils can cause fires if an oil leak occurs in area of hot equipment.液压系统仅有以下三种基本方法传递动力：电气，机械和流体。
液压专业词汇流体传动hydraulic power液压技术hydraulics液力技术hydrodynamics气液技术hydropneumatics运行工况operating conditions额定工况rated conditions极限工况limited conditions瞬态工况instantaneous conditions稳态工况steady-state conditions许用工况acceptable conditions连续工况continuous working conditions 实际工况actual conditions效率efficiency旋转方向direction of rotation公称压力nominal pressure工作压力working pressure进口压力inlet pressure出口压力outlet pressure压降pressure drop；differential pressure 背压back pressure启动压力breakout pressure充油压力charge pressure开启压力cracking pressure峰值压力peak pressure运行压力operating pressure耐压试验压力proof pressure冲击压力surge pressure静压力static pressure系统压力system pressure控制压力pilot pressure充气压力pre—charge pressure吸入压力suction pressure调压偏差override pressure额定压力rated pressure耗气量air consumption泄漏leakage内泄漏internal leakage外泄漏external leakage层流laminar flow紊流turbulent flow气穴cavitation流量flow rate排量displacement额定流量rated flow供给流量supply flow流量系数flower factor滞环hysteresis图形符号graphical symbol液压气动元件图形符号symbols for hydraulic and pneumatic components 流体逻辑元件图形符号symbols for fluid logic devices逻辑功能图形符号symbols for logic functions回路图circuit diagram压力－时间图pressure time diagram功能图function diagram循环circle自动循环automatic cycle工作循环working cycle循环速度cycling speed工步phase停止工步dwell phase工作工步working phase快进工步rapid advance phase快退工步rapid return phase频率响应frequency response重复性repeat ability复现性reproducibility漂移drift波动ripple线性度linearity线性区linear region液压锁紧hydraulic lock液压卡紧sticking变量泵variable displacement pump泵的控制control of pump齿轮泵gear pump叶片泵vane pump柱塞泵piston pump轴向柱塞泵axial piston pump法兰安装flange mounting底座安装foot mounting液压马达hydraulic motor刚度stiffness中位neutral position零位zero position自由位free position缸cylinder有杆端rod end无杆端rear end外伸行程extend stroke内缩行程retract stroke缓冲cushioning工作行程working stroke负载压力induced pressure输出力force实际输出力actual force单作用缸single—acting cylinder双作用缸double—acting cylinder差动缸differential cylinder伸缩缸telescopic cylinder阀valve底板sub—plate油路块manifold block板式阀sub—plate valve叠加阀sandwich valve插装阀cartridge valve滑阀slide valve锥阀poppet valve阀芯valve element阀芯位置valve element position单向阀check valve液控单向阀pilot—controlled check valve 梭阀shuttle valve压力控制阀pressure relief valve溢流阀pressure relief valve顺序阀sequence valve减压阀pressure reducing valve平衡阀counterbalance valve卸荷阀unloading valve直动式directly operated type先导式pilot—operated type机械控制式mechanically controlled type 手动式manually operated type液控式hydraulic controlled type流量控制阀flow control valve固定节流阀fixed restrictive valve可调节流阀adjustable restrictive valve 单向节流阀one-way restrictive valve 调速阀speed regulator valve分流阀flow divider valve集流阀flow—combining valve截止阀shut-off valve球阀global（ball) valve针阀needle valve闸阀gate valve膜片阀diaphragm valve蝶阀butterfly valve噪声等级noise level放大器amplifier模拟放大器analogue amplifier数字放大器digital amplifier传感器sensor阈值threshold伺服阀servo—valve四通阀four-way valve喷嘴挡板nozzle flapper液压放大器hydraulic amplifier颤振dither阀极性valve polarity流量增益flow gain对称度symmetry流量极限flow limit零位内泄漏null(quiescent）leakage 遮盖lap零遮盖zero lap正遮盖over lap负遮盖under lap开口opening零偏null bias零漂null drift阀压降valve pressure drop分辨率resolution频率响应frequency response幅值比amplitude ratio相位移phase lag传递函数transfer function管路flow line硬管rigid tube软管flexible hose工作管路working line回油管路return line补液管路replenishing line控制管路pilot line泄油管路drain line放气管路bleed line接头fitting；connection焊接式接头welded fitting扩口式接头flared fitting快换接头quick release coupling法兰接头flange connection弯头elbow异径接头reducer fitting流道flow pass油口port闭式油箱sealed reservoir油箱容量reservoir fluid capacity气囊式蓄能器bladder accumulator空气污染air contamination固体颗粒污染solid contamination液体污染liquid contamination空气过滤器air filter油雾气lubricator热交换器heat exchanger冷却器cooler加热器heater温度控制器thermostat消声器silencer双筒过滤器duplex filter过滤器压降filter pressure drop有效过滤面积effective filtration area 公称过滤精度nominal filtration rating 压溃压力collapse pressure填料密封packing seal机械密封mechanical seal径向密封radial seal旋转密封rotary seal活塞密封piston seal活塞杆密封rod seal防尘圈密封wiper seal；scraper组合垫圈bonded washer复合密封件composite seal弹性密封件elastomer seal丁腈橡胶nitrile butadiene rubber；NBR聚四氟乙烯polytetrafluoroethene;PTFE优先控制override control压力表pressure gauge压力传感器electrical pressure transducer 压差计differential pressure instrument液位计liquid level measuring instrument流量计flow meter压力开关pressure switch脉冲发生器pulse generator液压泵站power station空气处理单元air conditioner unit压力控制回路pressure control circuit安全回路safety circuit差动回路differential circuit调速回路flow control circuit进口节流回路meter-in circuit出口节流回路meter-out circuit同步回路synchronizing circuit开式回路open circuit闭式回路closed circuit管路布置pipe-work管卡clamper联轴器drive shaft coupling操作台control console控制屏control panel避震喉compensator粘度viscosity运动粘度kinematic viscosity密度density含水量water content闪点flash point防锈性rust protection抗腐蚀性anti-corrosive quality便携式颗粒检测仪portable particle counter Solenoid valve 电磁阀Check valve 单向阀Cartridge valve 插装阀Sandwich plate valve 叠加阀Pilot valve 先导阀Pilot operated check valve 液控单向阀Sub—plate mount 板式安装Manifold block 集成块Pressure relief valve 压力溢流阀Flow valve 流量阀Throttle valve 节流阀Double throttle check valve 双单向节流阀Rotary knob 旋钮Rectifier plate 节流板Servo valve 伺服阀Proportional valve 比例阀Position feedback 位置反馈Progressive flow 渐增流量De—energizing of solenoid 电磁铁释放二、介质类Phosphate ester （HFD—R) 磷酸甘油酯Water—glycol （HFC）水-乙二醇Emulsion 乳化液Inhibitor缓蚀剂Synthetic lubricating oil 合成油三、液压安装工程Contamination 污染Grout 灌浆Failure 失效Jog 点动Creep爬行Abrasion 摩擦Retract（活塞杆）伸出Extension （活塞杆）缩回Malfunction 误动作Pickling 酸洗Flushing 冲洗Dipping process 槽式酸洗Re-circulation 循环Passivity 钝化Nitric acid 柠檬酸Argon 氩气Butt welding 对接焊Socket welding 套管焊Inert gas welding 惰性气体焊四、管接头Bite type fittings 卡套式管接头Tube to tube fittings 接管接头union 直通接管接头union elbow 直角管接头union tee 三通管接头union cross 四通管接头Mal stud fittings 端直通管接头Bulkhead fittings 长直通管接头Weld fittings 焊接式管接头Female connector fittings 接头螺母Reducers extenders 变径管接头Banjo fittings 铰接式管接头Adjustable fittings/swivel nut 旋转接头五、伺服阀及伺服系统性能参数Dynamic response 动态频响DDV-direct drive valve 直动式伺服阀NFPA—National Fluid Power Association 美国流体控制学会Phase lag 相位滞后Nozzle flapper valve 喷嘴挡板阀Servo-jet pilot valve 射流管阀Dither 颤振电流Coil impedance 线圈阻抗Flow saturation 流量饱和Linearity 线形度Symmetry 对称性Hysterics 滞环Threshold 灵敏度Lap 滞后Pressure gain 压力增益Null 零位Null bias 零偏Null shift 零飘Frequency response 频率响应Slope 曲线斜坡液压系统（hydraulic system）执行元件（actuator)液压缸（cylinder）液压马达（motor）液压回路（circuit）压力控制回路（pressure control)流量（速度）控制回路（speed control)方向控制回路（directional valve control）安全回路（security control)定位回路（position control）同步回路（synchronise circuit）顺序动作回路（sequeunt circuit）液压泵（pump）阀（valve）压力控制阀（pressure valve）、流量控制阀（flow valve）方向控制阀（directional valve）液压辅件（accessory）普通阀（common valve）插装阀（cartridge valve）叠加阀（superimposed valve液压专业词汇流体传动hydraulic power液压技术hydraulics液力技术hydrodynamics气液技术hydropneumatics运行工况operating conditions额定工况rated conditions极限工况limited conditions瞬态工况instantaneous conditions稳态工况steady—state conditions许用工况acceptable conditions连续工况continuous working conditions实际工况actual conditions效率efficiency旋转方向direction of rotation公称压力nominal pressure工作压力working pressure进口压力inlet pressure出口压力outlet pressure压降pressure drop；differential pressure背压back pressure启动压力breakout pressure充油压力charge pressure开启压力cracking pressure峰值压力peak pressure运行压力operating pressure耐压试验压力proof pressure冲击压力surge pressure静压力static pressure系统压力system pressure控制压力pilot pressure充气压力pre-charge pressure吸入压力suction pressure调压偏差override pressure额定压力rated pressure耗气量air consumption泄漏leakage内泄漏internal leakage外泄漏external leakage层流laminar flow紊流turbulent flow气穴cavitation流量flow rate排量displacement额定流量rated flow供给流量supply flow流量系数flower factor滞环hysteresis图形符号graphical symbol液压气动元件图形符号symbols for hydraulic and pneumatic components 流体逻辑元件图形符号symbols for fluid logic devices逻辑功能图形符号symbols for logic functions回路图circuit diagram压力－时间图pressure time diagram功能图function diagram循环circle自动循环automatic cycle工作循环working cycle循环速度cycling speed工步phase停止工步dwell phase工作工步working phase快进工步rapid advance phase快退工步rapid return phase频率响应frequency response重复性repeat ability复现性reproducibility漂移drift波动ripple线性度linearity线性区linear region液压锁紧hydraulic lock液压卡紧sticking变量泵variable displacement pump泵的控制control of pump齿轮泵gear pump叶片泵vane pump柱塞泵piston pump轴向柱塞泵axial piston pump法兰安装flange mounting底座安装foot mounting液压马达hydraulic motor刚度stiffness中位neutral position零位zero position自由位free position缸cylinder有杆端rod end无杆端rear end外伸行程extend stroke内缩行程retract stroke缓冲cushioning工作行程working stroke负载压力induced pressure输出力force实际输出力actual force单作用缸single—acting cylinder双作用缸double-acting cylinder差动缸differential cylinder伸缩缸telescopic cylinder阀valve底板sub—plate油路块manifold block板式阀sub—plate valve叠加阀sandwich valve插装阀cartridge valve滑阀slide valve锥阀poppet valve阀芯valve element阀芯位置valve element position单向阀check valve液控单向阀pilot—controlled check valve 梭阀shuttle valve压力控制阀pressure relief valve溢流阀pressure relief valve顺序阀sequence valve减压阀pressure reducing valve平衡阀counterbalance valve卸荷阀unloading valve直动式directly operated type先导式pilot-operated type机械控制式mechanically controlled type 手动式manually operated type液控式hydraulic controlled type流量控制阀flow control valve固定节流阀fixed restrictive valve可调节流阀adjustable restrictive valve 单向节流阀one—way restrictive valve 调速阀speed regulator valve分流阀flow divider valve集流阀flow—combining valve截止阀shut—off valve球阀global(ball）valve针阀needle valve闸阀gate valve膜片阀diaphragm valve蝶阀butterfly valve噪声等级noise level放大器amplifier模拟放大器analogue amplifier数字放大器digital amplifier传感器sensor阈值threshold伺服阀servo—valve四通阀four—way valve喷嘴挡板nozzle flapper液压放大器hydraulic amplifier颤振dither阀极性valve polarity流量增益flow gain对称度symmetry流量极限flow limit零位内泄漏null(quiescent）leakage遮盖lap零遮盖zero lap正遮盖over lap负遮盖under lap开口opening零偏null bias零漂null drift阀压降valve pressure drop分辨率resolution频率响应frequency response幅值比amplitude ratio相位移phase lag传递函数transfer function管路flow line硬管rigid tube软管flexible hose工作管路working line回油管路return line补液管路replenishing line控制管路pilot line泄油管路drain line放气管路bleed line接头fitting；connection焊接式接头welded fitting扩口式接头flared fitting快换接头quick release coupling 法兰接头flange connection弯头elbow异径接头reducer fitting流道flow pass油口port闭式油箱sealed reservoir油箱容量reservoir fluid capacity 气囊式蓄能器bladder accumulator 空气污染air contamination固体颗粒污染solid contamination 液体污染liquid contamination空气过滤器air filter油雾气lubricator热交换器heat exchanger冷却器cooler加热器heater温度控制器thermostat消声器silencer双筒过滤器duplex filter过滤器压降filter pressure drop有效过滤面积effective filtration area公称过滤精度nominal filtration rating压溃压力collapse pressure填料密封packing seal机械密封mechanical seal径向密封radial seal旋转密封rotary seal活塞密封piston seal活塞杆密封rod seal防尘圈密封wiper seal;scraper组合垫圈bonded washer复合密封件composite seal弹性密封件elastomer seal丁腈橡胶nitrile butadiene rubber；NBR 聚四氟乙烯polytetrafluoroethene；PTFE 优先控制override control压力表pressure gauge压力传感器electrical pressure transducer 压差计differential pressure instrument液位计liquid level measuring instrument 流量计flow meter压力开关pressure switch脉冲发生器pulse generator液压泵站power station空气处理单元air conditioner unit压力控制回路pressure control circuit安全回路safety circuit差动回路differential circuit调速回路flow control circuit进口节流回路meter—in circuit出口节流回路meter—out circuit同步回路synchronizing circuit开式回路open circuit闭式回路closed circuit管路布置pipe—work管卡clamper联轴器drive shaft coupling操作台control console控制屏control panel避震喉compensator粘度viscosity运动粘度kinematic viscosity密度density含水量water content闪点flash point防锈性rust protection抗腐蚀性anti-corrosive quality便携式颗粒检测仪portable particle counter Solenoid valve 电磁阀Check valve 单向阀Cartridge valve 插装阀Sandwich plate valve 叠加阀Pilot valve 先导阀Pilot operated check valve 液控单向阀Sub-plate mount 板式安装Manifold block 集成块Pressure relief valve 压力溢流阀Flow valve 流量阀Throttle valve 节流阀Double throttle check valve 双单向节流阀Rotary knob 旋钮Rectifier plate 节流板Servo valve 伺服阀Proportional valve 比例阀Position feedback 位置反馈Progressive flow 渐增流量De—energizing of solenoid 电磁铁释放二、介质类Phosphate ester (HFD—R）磷酸甘油酯Water—glycol (HFC）水—乙二醇Emulsion 乳化液Inhibitor缓蚀剂Synthetic lubricating oil 合成油三、液压安装工程Contamination 污染Grout 灌浆Failure 失效Jog 点动Creep爬行Abrasion 摩擦Retract（活塞杆）伸出Extension (活塞杆）缩回Malfunction 误动作Pickling 酸洗Flushing 冲洗Dipping process 槽式酸洗Re-circulation 循环Passivity 钝化Nitric acid 柠檬酸Argon 氩气Butt welding 对接焊Socket welding 套管焊Inert gas welding 惰性气体焊四、管接头Bite type fittings 卡套式管接头Tube to tube fittings 接管接头union 直通接管接头union elbow 直角管接头union tee 三通管接头union cross 四通管接头Mal stud fittings 端直通管接头Bulkhead fittings 长直通管接头Weld fittings 焊接式管接头Female connector fittings 接头螺母Reducers extenders 变径管接头Banjo fittings 铰接式管接头Adjustable fittings/swivel nut 旋转接头五、伺服阀及伺服系统性能参数Dynamic response 动态频响DDV-direct drive valve 直动式伺服阀NFPA—National Fluid Power Association 美国流体控制学会Phase lag 相位滞后Nozzle flapper valve 喷嘴挡板阀Servo—jet pilot valve 射流管阀Dither 颤振电流Coil impedance 线圈阻抗Flow saturation 流量饱和Linearity 线形度Symmetry 对称性Hysterics 滞环Threshold 灵敏度Lap 滞后Pressure gain 压力增益Null 零位Null bias 零偏Null shift 零飘Frequency response 频率响应Slope 曲线斜坡液压系统(hydraulic system)执行元件（actuator）液压缸（cylinder）液压马达（motor）液压回路（circuit）压力控制回路（pressure control）流量(速度）控制回路（speed control)方向控制回路（directional valve control）安全回路（security control）定位回路（position control)同步回路（synchronise circuit)顺序动作回路(sequeunt circuit）液压泵（pump）阀（valve)压力控制阀（pressure valve)、流量控制阀(flow valve）方向控制阀（directional valve)液压辅件（accessory）普通阀（common valve）插装阀（cartridge valve）叠加阀（superimposed valve。
附录外文文献原文：The commonly used sources of power in hydraulic systems are pumps and accumulators .Similarly,accumulator connected to atmosphere will dischange oil at atmosphere pressure until it empty. only when connected to a system having resistance to flow can pressure be developed.Three types of pumps find use in fluid-power systems:rotary,reciprocating or piston-type, and 3,centrifugal pumps.Simple hydraulic system may use but one type of pump . The trend is to use pumps with the most satisfactory characteristics for the specific tasks involved . In matching the characteristics of the pump to the requirements of the hydraulic system , it is not unusual to find two types of pumps in series . For example , a centrifugal pump may be to supercharge a reciprocating pump , or a rotary pump may be used to supply pressurized oil for the contronls associated with a reversing variabledisplacement pumps . Most power systems require positive displacement pumps . At high pressure , reciprocating pumps are often preferred to rotary pumps .1、Rotary pumpsThese are built in many differnt designs and extremely popular in modern fluid power system . The most common rotay-pump designs used today are spurgear , internal gear ,generated rotor , sliding vane ,and screew pumps . Ehch type has advantages that make it most suitable for a given application .2、Gear pumpsGear pumps are the simplest type of fixed displacement hydraulic pump available . This type consists of two external gear , generally spur gear , within a closed-fitting housing . One of the gear is driven directly by the pump drive shaft . It ,in turn , then drives the second gear . Some designs utilize helical gears ,but the spur gear design predominates . Gear pumps operate on a very simple principle . As the gear teeth unmesh , the volume at the inlet port A expands , a partial vacuum on the suction side of the pump will be formed . Fluid from an external reservoir or tank is forced by atmospheric pressure into the pumpinlet . The continuous action of the fluid being carried from the inlet to the discharge side one of the pump forces the fluid into the system .3、Vane pumpsThe vane pump consists of a housing that is eccentric or offset with respect to the drive shaft axis . In some models this inside surface consists of a cam ring that can be rotated to shift the relationship between rotor are rectangular and extend radially from a center radius to the outside diameter of the rotor and from end to end . A rectangular vane that is essentially the same size as the slot is inserted in the slot and is free to slide in and out .As the rotor turns , the vanes thrust outward , and the vane tips track the inner surface of the housing , riding on a thin film of fluid . Two port or end plates that engage the end face of the ring provide axial retention .Centrifugal force generally contributes to outward thrust of the vane . As they ride along the eccentric housing surface , the vane move in and out of the rotor slots . The vane divide the area between the rotor and casing into a series of chambers .The sides of each chamber are formed by two adjacent vanes ,the port or end plates , the pump casing and the rotor . These chambers change in change in volume depending on their respective position about the shaft .As each chamber approaches the inlet port , its vanes move outward and its volume expands , causing fluid to flow into the expanded chamber . Fluid is then carried within the chamber around to the dischange port . As the chamber approaches the discharge port , its vanes are pushed inward ,the volume is reduced , and the fluid is forced out the discharge port .Vane pump speed is limited by vane peripheral speed . High peripheral speed will cause cavitation in suction cavity . which results in pump damage and reduced flow .An imbalance of the vanes can cause the oil film between the vane tips and the cam ring to break down , resulting in metal-to-metal contact and subsequent increased wear and slipage . One metheod applied to eliminate high vane thrust loading is a dual-vane construction .4、Piston-type pumpAll piston pumps operate by allowing oil to flow into a pumping cavity as a piston retreats and then forcing the oil out into another chamber as the piston advances . Design differences among pumps lie primarily in the methods of separating inlet from outlet oil .5、In-line piston pumpThe siplest typeof axial piston pump is the swash plate in-line design .The cylinder are connected though piston shoes and a retracting ring , so that the shoes beat anainst an angled swash plate . As the block turns ,the piston shoes follow the swash plate ,causing the piston to reciprocate . The ports are arranged in the valve plate so that the pistons pass the inlet port as they are being pulled out and pass the outlet port as they are being forcing back in .The angle of the swash plate controls the delibery . Where the swash plate is fixed , the pump is of the constant-displacement type . In the variable-displacement , inline piston pump , the swash plate is moumted on a pivoted yoke . As the swash plate angle is increased , the cylinder stroke is increase , resulting in a greater flow . A pressure compensator control can position the yoke automatically to maintain a constant output pressure .6、BENT-axis piston pumpAs the shaft roates , distance between any one piston and the valving surface changes continually . Each piston moves away from the valving surface during one half of the revolution and toward the valving surface during the other half . The inlet chamber is in line as the pistons move away , and the outletr chamber is in line as the pistons move closer , thus drawing liquiring in during one half of the inlet chamber as the pistons are moving away from the pintle . Thereforce , during rotation , pistons draw liquid into the cylinder bores as they pass the inlet side of the pinntle and force that liquid out of the bores as they pass the outlet side of the pintle . The displacement of this pump varies with the offset angle , the maximum angle being 30 degree ,the minimum zero . Fixed displacement models are usually avaiable with 23 degree angle .In the variable displacement construction a yoke with an external control is used to change the angle . With some contronls , the yoke can be moved over center to reverse the direction of flow from the pump .7、Pump/system interactionPressure-compensated variavle delivery pumps do not require a relief valve in the high pressure line . The pressure compensation feature eliminates the need for the relief valve .In nearly all working systems ,however , at least one is used on just-in-case basis . The use of a pressure compensator , while avoiding dependence on a relief valve , brings on its own problems .The actuator -spring-spool arrangement in the compensator is a dynamic , damped-mass-spring arrangement .However , when the system calls for a chang in axhievetheir maxmum volume as they reach the inlet port , the maximum volume of fluid will ve moved .If the relationship between housing and rotor is changed such that the chambers achieve their minimum of zero volume as they reach the inlet port , the pump delivery will be reduced to zero .Vane pump speed is limited by vane peripheral speed . High peripheral speed will cause cavitation in suction cavity , which results in pump damage and reduced flow . An imbalance of the vanes can cause the oil film between the cane tips and the cam ring to break down , resulting in metal-to-metal contact and subsequent increased wear and slipage . One method applied to eliminate high vane thrust loading is a dual-vane construction . In the dual-vane construction , tow independent vanes are located in each totor slot chmbered edges along the sides and top of each vane from a channel that essentially balances the hydraulic pressure on the top and bottom of each pair of vanes .Centrifugal force cause the vane to follow the contour of the cam-shaped ring .There is just sufficient seal between the vanes and ring without destroying the thin oil film .外文文献中文翻译：常用的液压系统的动力源是泵和蓄能器。
