机械加工工艺制造工程与技术外文文献翻译

题目机械加工介绍学院专业班级姓名学号指导教师Machining Processing Introduction1 LatheLathes are machine tools designed primarily to do turning, facing and bori ng, Very little turning is done on other types of machine tools, and none can do it with equal facility. Because lathes also can do drilling and reaming, their versatility permits several operations to be done with a single setup of the work piece. Consequently, more lathes of various types are used in manufacturing than any other machine tool.The essential components of a lathe are the bed, headstock assembly, tailstock assembly, and the leads crew and feed rod.The bed is the backbone of a lathe. It usually is made of well normalized or aged gray or nodular cast iron and provides s heavy, rigid frame on which all the other basic components are mounted. Two sets of parallel, longitudinal ways, inner and outer, are contained on the bed, usually on the upper side. Som makers use an inverted V-shape for all four ways, whereas others utilize one inverted V and one flat way in one or both sets, they are precision-machined to assure accuracy of alignment. On most modern lathes the way are surface-hardened to resist wear and abrasion, but precaution should be taken in operating a lathe to assure that the ways are not damaged. Any inaccuracy in them usually means that the accuracy of the entire lathe is destroyed.The headstock is mounted in a foxed position on the inner ways, usually at the left end of the bed. It provides a powered means of rotating the word at various speeds. Essentially, it consists of a hollow spindle, mounted in accurate bearings, and a set of transmission gears-similar to a truck transmission—through which the spindle can be rotated at a number of speeds. Most lathes provide from 8 to 18 speeds, usually in a geometric ratio, and on modern lathes all the speeds can be obtained merely by moving from two to four levers. An increasing trend is to provide a continuously variable speed range through electrical or mechanical drives.Because the accuracy of a lathe is greatly dependent on the spindle, it is of heavy construction and mounted in heavy bearings, usually preloaded tapered roller or ball types. The spindle has a hole extending through its length through which long bar stock can be fed. The size of maximum size of bar stock that can be machined when the material must be fed through spindle.The tailsticd assembly consists, essentially, of three parts. A lower casting fits on the inner ways of the bed and can slide longitudinally thereon, with means for clamping the entire assembly in any desired location; an upper casting fits on the lower one and can be moved transversely upon it, on some type of keyed ways, to permit aligning the assembly is the tailstock quill. This is hollow steel cylinder, usually about 51 to 76mm (2to 3 inches) in diameter, that can be moved several inches longitudinally in and out of the upper casting by means of a hand wheel and screw.The size of a lathe is designated by two dimensions. The first is known as theswing. This is the maximum diameter of work that can be rotated on a lathe. It is approximately twice the distance between the line connecting the lathe centers and the nearest point on the ways, the second size dimension is the maximum distance between centers. The swing thus indicates the maximum work piece diameter that can be turned in the lathe, while the distance between centers indicates the maximum length of work piece that can be mounted between centers.Engine lathes are the type most frequently used in manufacturing. They are heavy-duty machine tools with all the components described previously and have power drive for all tool movements except on the compound rest. They commonly range in size from 305 to 610 mm(12 to 24 inches)swing and from 610 to 1219 mm(24 to 48 inches) center distances, but swings up to 1270 mm(50 inches) and center distances up to 3658mm(12 feet) are not uncommon. Most have chip pans and a built-in coolant circulating system. Smaller engine lathes-with swings usually not over 330 mm (13 inches) –also are available in bench type, designed for the bed to be mounted on a bench on a bench or cabinet.Although engine lathes are versatile and very useful, because of the time required for changing and setting tools and for making measurements on the work piece, thy are not suitable for quantity production. Often the actual chip-production tine is less than 30% of the total cycle time. In addition, a skilled machinist is required for all the operations, and such persons are costly and often in short supply. However, much of the operator’s time is consumed by simple, repetitious adjustments and in watching chips being made. Consequently, to reduce or eliminate the amountof skilled labor that is required; turret lathes, screw machines, and other types of semiautomatic and automatic lathes have been highly developed and are widely used in manufacturing.2 Numerical ControlOne of the most fundamental concepts in the area of advanced manufacturing technologies is numerical control (NC). Prior to the advent of NC, all machine tools ere manually operated and controlled. Among the many limitations associated with manual control machine tools, perhaps none is more prominent than the limitation of operator skills. With manual control, the quality of the product is directly related to and limited to the skills of the operator. Numerical control represents the first major step away from human control of machine tools.Numerical control means the control of machine tools and other manufacturing systems through the use of prerecorded, written symbolic instructions. Rather than operating a machine tool, an NC technician writes a program that issues operational instructions to the machine tool. For a machine tool to be numerically controlled, it must be interfaced with a device for accepting and decoding the programmed instructions, known as a reader.Numerical control was developed to overcome the limitation of human operators, and it has done so. Numerical control machines are more accurate than manually operated machines, they can produce parts more uniformly, they are faster, and the long-run tooling costs are lower. The development of NC led to the development of several other innovations in manufacturing technology:Electrical discharge machining, Laser cutting, Electron beam welding.Numerical control has also made machine tools more versatile than their manually operated predecessors. An NC machine tool can automatically produce a wide of parts, each involving an assortment of widely varied and complex machining processes. Numerical control has allowed manufacturers to undertake the production of products that would not have been feasible from an economic perspective using manually controlled machine tolls and processes.Like so many advanced technologies, NC was born in the laboratories of the Massachusetts Institute of Technology. The concept of NC was developed in the early 1950s with funding provided by the U.S. Air Force. In its earliest stages, NC machines were able to made straight cuts efficiently and effectively.However, curved paths were a problem because the machine tool had to be programmed to undertake a series of horizontal and vertical steps to produce a curve. The shorter the straight lines making up the steps, the smoother is the curve, each line segment in the steps had to be calculated.This problem led to the development in 1959 of the Automatically Programmed Tools (APT) language. This is a special programming language for NC that uses statements similar to English language to define the part geometry, describe the cutting tool configuration, and specify the necessary motions. The development of the APT language was a major step forward in the fur ther development from those used today. The machines had hardwired logic circuits. The instructional programs were written on punched paper, which was later to be replaced by magnetic plastic tape. Atape reader was used to interpret the instructions written on the tape for the machine. Together, all of this represented a giant step forward in the control of machine tools. However, there were a number of problems with NC at this point in its development.A major problem was the fragility of the punched paper tape medium. It was common for the paper tape containing the programmed instructions to break or tear during a machining process. This problem was exacerbated by the fact that each successive time a part was produced on a machine tool; the paper tape carrying the programmed instructions had to be rerun through the reader. If it was necessary to produce 100 copies of a given part, it was also necessary to run the paper tape through the reader 100 separate tines. Fragile paper tapes simply could not withstand the rigors of a shop floor environment and this kind of repeated use.This led to the development of a special magnetic plastic tape. Whereas the paper carried the programmed instructions as a series of holes punched in the tape, the plastic tape carried the instructions as a series of magnetic dots. The plastic tape was much stronger than the paper tape, which solved the problem of frequent tearing and breakage. However, it still left two other problems.The most important of these was that it was difficult or impossible to change the instructions entered on the tape. To make even the most minor adjustments in a program of instructions, it was necessary to interrupt machining operations and make a new tape. It was also still necessary to run the tape through the reader as many times as there were parts to be produced. Fortunately, computer technology became areality and soon solved the problems of NC associated with punched paper and plastic tape.The development of a concept known as direct numerical control (DNC) solved the paper and plastic tape problems associated with numerical control by simply eliminating tape as the medium for carrying the programmed instructions. In direct numerical control, machine tools are tied, via a data transmission link, to a host computer. Programs for operating the machine tools are stored in the host computer and fed to the machine tool an needed via the data transmission linkage. Direct numerical control represented a major step forward over punched tape and plastic tape. However, it is subject to the same limitations as all technologies that depend on a host computer. When the host computer goes down, the machine tools also experience downtime. This problem led to the development of computer numerical control.3 TurningThe engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in today’s production shops by a wide variety of automatic lathes such as automatic of single-point tooling for maximum metal removal, and the use of form tools for finish on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret Lathes Production machining equipment must be evaluated now, more than ever before, this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turrets lathe, the designer should strive for a minimum of operations.Automatic Screw Machines Generally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle automatics and automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the automatic screw machine has long since exceeded the confines of this narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic screw machine. Quantities less than on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer Lathes Since surface roughness depends greatly on material turned, tooling , and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.In some cases, tolerances of 0.05mm are held in continuous production using but one cut . groove width can be held to 0.125mm on some parts. Bores and single-point finishes can be held to 0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of 0.125mm is economical on both diameter and length of turn.机械加工介绍1.车床车床主要是为了进行车外圆、车端面和镗孔等项工作而设计的机床。

翻译人：王墨墨山东科技大学文献题目：Automated Calibration of Robot Coordinatesfor Reconfigurable Assembly Systems翻译正文如下：针对可重构装配系统的机器人协调性的自动校准T.艾利，Y.米达，H.菊地，M.雪松日本东京大学，机械研究院，精密工程部摘要为了实现流水工作线更高的可重构性，以必要设备如机器人的快速插入插出为研究目的。

当一种新的设备被装配到流水工作线时，应使其具备校准系统。

该研究使用两台电荷耦合摄像机，基于直接线性变换法，致力于研究一种相对位置/相对方位的自动化校准系统。

摄像机被随机放置，然后对每一个机械手执行一组动作。

通过摄像机检测机械手动作，就能捕捉到两台机器人的相对位置。

最佳的结果精度为均方根值0.16毫米。

关键词：装配，校准，机器人1 介绍21世纪新的制造系统需要具备新的生产能力，如可重用性，可拓展性，敏捷性以及可重构性[1]。

系统配置的低成本转变，能够使系统应对可预见的以及不可预见的市场波动。

关于组装系统，许多研究者提出了分散的方法来实现可重构性[2][3]。

他们中的大多数都是基于主体的系统，主体逐一协同以建立一种新的配置。

然而，协同只是目的的一部分。

在现实生产系统中，例如工作空间这类物理问题应当被有效解决。

为了实现更高的可重构性，一些研究人员不顾昂贵的造价，开发出了特殊的均匀单元[4][5][6]。

作者为装配单元提出了一种自律分散型机器人系统，包含多样化的传统设备[7][8]。

该系统可以从一个系统添加/删除装配设备，亦或是添加/删除装配设备到另一个系统；它通过协同作用，合理地解决了工作空间的冲突问题。

我们可以把该功能称为“插入与生产”。

在重构过程中，校准的装配机器人是非常重要的。

这是因为，需要用它们来测量相关主体的特征，以便在物理主体之间建立良好的协作关系。

这一调整必须要达到表1中所列到的多种标准要求。

外文原文：Machining TurningThe engine lathe, one of the oldest metal removal machines, has a number of useful and highly desirable attributes. Today these lathes are used primarily in small shops where smaller quantities rather than large production runs are encountered.The engine lathe has been replaced in today’s production shops by a wide variety of automatic lathes such as automatic tracer lathes, turret lathes, and automatic screw machines. All the advantages of single-point tooling for maximum metal removal, and the use of form tools for finished on a par with the fastest processing equipment on the scene today.Tolerances for the engine lathe depend primarily on the skill of the operator. The design engineer must be careful in using tolerances of an experimental part that has been produced on the engine lathe by a skilled operator. In redesigning an experimental part for production, economical tolerances should be used.Turret LathesProduction machining equipment must be evaluated now, more than ever before, in terms of ability to repeat accurately and rapidly. Applying this criterion for establishing the production qualification of a specific method, the turret lathe merits a high rating.In designing for low quantities such as 100 or 200 parts, it is most economical to use the turret lathe. In achieving the optimum tolerances possible on the turret lathe, the designer should strive for a minimum of operations.Automatic Screw MachinesGenerally, automatic screw machines fall into several categories; single-spindle automatics, multiple-spindle rapid, automatic chucking machines. Originally designed for rapid, automatic production of screws and similar threaded parts, the narrow field, and today plays a vital role in the mass production of a variety of precision parts. Quantities play an important part in the economy of the parts machined on the automatic screw machine. The cost of the parts machined can be reduced if the minimum economical lot size is calculated and the proper machine is selected for these quantities.Automatic Tracer LathesSince surface roughness depends greatly upon material turned, tooling, and feeds and speeds employed, minimum tolerances that can be held on automatic tracer lathes are not necessarily the most economical tolerances.In some cases, tolerances of ±0.05mm are held in continuous production using but one cut. Groove width can be held to ±0.0125mm on some parts. Bores and single-point finishes can be held to ±0.0125mm. On high-production runs where maximum output is desirable, a minimum tolerance of ±0.125mm is economical on both diameter and length of turn.MillingWith the exceptions of turning and drilling, milling is undoubtedly the most widely used method of removing metal. Well suited and readily adapted to the economical production of any quantity of parts, the almost unlimited versatility of milling process merits the attention and consideration of designers seriously with the manufacture of their product.As in any other process, parts that have to be milled should be designed with economical tolerances that can be achieved in production mill. If the part is designed with tolerances finer than necessary, additional operations will have to be added to achieve these tolerances-and this will increase the cost of the part.GrindingGrinding is one of the most widely used methods of finishing parts to extremely close tolerances and fine surface finishes. Currently, there are grinders for almost every type of grinding machine required. Where processing costs are excessive, parts redesigned to worthwhile. For example, wherever possible the production economy of centerless grinding should be taken advantage of by proper design consideration.Although grinding is usually considered a finishing operation, it is often employed as a complete machining process on work which can be ground down from rough condition without being turned or otherwise machined. Thus many types of forgings and other parts are finished completely with the grinding wheel at appreciable savings of time and expense.Classes of grinding machines include the following: cylindrical grinders, centerless grinders, internal grinders, surface grinders, and tool expense.The cylindrical and centerless grinders or taper work; thus splines, shafts, and similar parts are ground on cylindrical machines either of the common-center type orthe centerless machine.Thread grinders are used for grinding precision threads for thread gages, and threads on precision parts where the concentricity between the diameter of the shaft and pitch diameter of thread must be held to close tolerances.The internal grinders are used for grinding of precision holes, cylinder bores, and similar operations where bores of all kinds are to be finished.The surface grinders are for finishing all kinds of flat work, or work with plain surfaces which may be operated upon either by the edge of a wheel or by the face of a grinding wheel. These machines may have reciprocating or rotating tables.译文：机械加工金属切削机床中最早的一种是普通车床，当今仍有许多有用的特性。

外文出处：《Manufacturing Engineering and Technology—Maching》附件1：外文原文ManipulatorFirst, an overview of industrial manipulatorWith the rapid development of China's industrial production, especially the reform and openingup after the rapid increase in the degree of automation to achieve the workpiece handling, steering,transmission or operation of brazing, spray gun, wrenches and other tools for processing and assembly operations since, which has more and more attracted our attention. Robot is to imitate the manual part of the action, according to a given program, track and requirements for automatic capture, handling or operation of the automatic mechanical devices.Production of mechanical hand can increase the automation level of production and labor productivity; can reduce labor intensity, ensuring product quality, to achieve safe production; particularly in the high-temperature, high pressure, low temperature, low pressure, dust, explosive, toxic andradioactive gases such as poor environment can replace the normal working people. Here I would like to think of designing a robot to be used in actual production.Why would a robot designed to provide a pneumatic power:1." Air inexhaustible, used later discharged into the atmosphere, does not require recycling and disposal, do not pollute the environment. (Concept of environmental protection)2." Air stick is small, the pipeline pressure loss is small (typically less than asphalt gas path pressure drop of one-thousandth), to facilitate long-distance transport.5." The air cleaner media, it will not degenerate, not easy to plug the pipeline. But there are also places where it fly in the ointment:2." As the use of low atmospheric pressure, the output power can notbe too large; in order to increase the output power is bound to the structure of the entire pneumaticsystem size increased.Air inexhaustible, used later discharged into the atmosphere, without recycling and disposal, donot pollute the environment. Accidental or a small amount of leakage would not be a serious impact on production. Viscosity of air is small, the pipeline pressure loss also is very small, easy long-distance transport.Compared with the hydraulic transmission, and its faster action and reaction, which is one of the outstanding merits of pneumatic.1.Implementing agencies2. Transmission3. Control SystemRobots are generally divided into three categories:Main features:First, mechanical hand (the upper and lower material robot, assembly robot, handling robot, stacking robot, help robot, vacuum handling machines, vacuum suction crane, labor-saving spreader, pneumatic balancer, etc.).Second, cantilever cranes (cantilever crane, electric chain hoist crane, air balance the hanging, etc.)Third, rail-type transport system (hanging rail, light rail, single girder cranes, double-beam crane)Four, industrial machinery, application of hand(3) The working conditions may be poor, monotonous, repetive easy to sub-fatigue working environment to replace human labor.(4) May be in dangerous situations, such as military goods handling, dangerous goods and hazardous materials removal and so on..(5) Universe and ocean development.(6), military engineering and biomedical research and testing.Help mechanical hands:附件1：外文资料翻译译文机械手机械手是近几十年发展起来的一种高科技自动化生产设备。

机械加工中英文资料外文翻译文献机械加工介绍作为产生形状的一种加工方法，机械加工是所有制造过程中最普遍使用的而且是最重要的方法。

机械加工过程是一个产生形状的过程，在这过程中，驱动装置使工件上的一些材料以切屑的形式被去除。

尽管在某些场合，工件无承受的情况下，使用移动式装备来实现加工，但大多数的机械加工是通过既支承工件又支承刀具的装备来完成。

加工知识的过程有两个方面。

小批生产低费用。

对于铸造、锻造和压力加工，每一个要生产的具体工件形状，即使是一个零件，几乎都要花费高额的加工费用。

靠焊接来产生的结构形状，在很大程度上取决于有效的原材料的形式。

一般来说，通过利用贵重设备而又无需特种加工条件下，几乎可以以任何种类原材料开始，借助机械加工把原材料加工成任意所需要的结构形状，只要外部尺寸足够大，那都是可能的。

因此对于生产一个零件，甚至当零件结构及要生产的批量大小上按原来都适于用铸造、锻造或者压力加工来生产的，但通常宁可选择机械加工。

严密的精度和良好的表面光洁度，机械加工的第二方面用途是建立在高精度和可能的表面光洁度基础上。

许多零件，如果用别的其他方法来生产属于大批量生产的话，那么在机械加工中则是属于低公差且又能满足要求的小批量生产了。

另方面，许多零件靠较粗的生产加工工艺提高其一般表面形状，而仅仅是在需要高精度的且选择过的表面才进行机械加工。

例如内螺纹，除了机械加工之外，几乎没有别的加工方法能进行加工。

又如已锻工件上的小孔加工，也是被锻后紧接着进行机械加工才完成的。

1 基本的机械加工参数切削中工件与刀具的基本关系是以以下四个要素来充分描述的：刀具的几何形状，切削速度，进给速度，和背吃刀量。

切削刀具必须用一种合适的材料来制造，它必须是强固、韧性好、坚硬而且耐磨的。

刀具的几何形状——以刀尖平面和刀具角为特征——对于每一种切削工艺都必须是正确的。

切削速度是切削刃通过工件表面的速率，它是以每分钟英寸来表示。

为了有效地加工，切削速度高低必须适应特定的工件——刀具配合。

成组技术外文文献翻译、机械加工工艺方面外文翻译、中英文翻译外文原文：Group TechnologyGroup technology GT is a very important methodology in today’s manufacturing significant. The reason for this is that group technology, when utilized to its fullest extent, can affect most areas of manufacturing, including design, process planning, scheduling, routing, factory layout, procurement, quality assurance, machine tool utilization, tool design, producibility engineering, and assembly.1 IntroductionGroup technology is a simple concept that is used widely in various forms. For a variety of reasons, it is logical to collect and associate things based on features that they have in common. This approach is familiar to everyone for plants, animals, and chemicals. Such organizational structures have also been used for hardware and other obviously similar products within the manufacturing world. Group technology represents structured categorization of particular value to the manufacturing community. It is already widely used; perhaps 50% of manufacturing companies use some form of GT.Bath or lot production suffers from many inefficiencies due to part variety and the general-purpose nature flexibility requirements of machine tools in use on the shop floor. In fact, a Cincinnati Milacron study showed that 95% of the time a part spends on the shop floor is idle time, the other 5% is divided between setup and teardown of the machine tool. The future breakdown of the 5% of on-machine time was developed by Dunlap. Based on this estimate, only 24% of the 5% is time which actually involves cutting; i.e., parts are being machined during only 1.2% of the total time spent in manufacturing. Group technology makes possible the application of several methods of analysis which assist in making batch production more efficient by reducing part variety via part families and improving throughout and work-in-process inventory. It is for this reason that group technology is becoming a key concept in manufacturing.2 DefinitionManufacturing philosophy to some, fundamental building block for more efficient production to most, group technology is a simple concept which utilizes/exploits similarities for more efficient production in bath manufacturing. Group technology usually classifies parts in the form of a code which is assigned to each part based on its shape or production processing characteristics. In use, coding parts assists in the control of planning and processing. This added control, which exploits similarities, leads to economies in the overall manufacturing process.The actual operator on the shop floor may never know this code, but designers, engineers, and planners find it an invaluable tool, allowing them to do more productive and useful analysis.3 General BenefitsIn practice, group technology is really nothing more than an information/indexing system. However, because of its focus on part design and processing similarities, analysis is possible which creates manufacturing economies of scale, encourages standardization, and eliminates duplication in design and process planning.Mass production enjoys the benefits of what are called economies of scale. Economies of scale achieved by processing a large number of parts over the same workstations or equipment. This result in less labor per part, more efficient machine utilization, and a faster turnover of inventory. Batch production in the past has not enjoyed economies of scale because of the need to remain flexible for changing part types and products. However, by grouping parts into families based on their similarities, much of the manufacturing processing of these parts can be done on entire families. This increases the number of parts processed with the same equipment conditions, thereby permitting some of the economies of scale of mass production.Standardization is achieved in both design and part process planning. Essentially, group technology creates an efficient design retrievalsystem since parts have been code based on shape. Similar design are located quickly and aspects such as part tolerances and producibility can be better understood, more easily applied, and kept more consistent from design to design. When standardized process planes are developed and include in the group technology code, new parts and repeat orders can follow similar processing routes through the shop floor, simplifying scheduling and flow through the shop.Group technology eliminates duplication. In both design and process planning, there is much les “reinventing of the wheel” since there is sufficient retrieval of standard designs and process plans.4 Application of GT in Process PlanningAlthough many areas of business operation can benefit from GT, manufacturing, the original application area, continues to be the place where GT is most widely practiced. Two important tasks in manufacturing planning and manufacturing engineering are scheduling and process planning. Job scheduling sets the order in which parts should be processed and can determine expected completion times for operation and orders. Process planning, on the other hand, decides the sequence of machines to which a part should be routed when it is manufactured and the operations that should be performed at each machine. Process planning also encompasses tool, jig, and fixture selection as well as documentation of the time standards run and setup time associated with each operation.Process planning can directly affect scheduling efficiency and, thus, many of the performance measures normally associated with manufacturing planning and control.Some of the largest productivity gains have been reported in the creation of process plans that determine how a part should be produced. With computer-aided process planning CAPP and GT it is possible to standardize such plans, reduce the number of new ones, and store, retrieve, edit, and print them out very efficiently.Process planning normally is not a formal procedure. Each time a new part is designed, a process planner will look at the drawing and decide which machine tools should process the parts, which operations should be performed, and in what sequenceThere are two reasons why companies often generate excess process plans. First, most companies have several planners, and each may come up with a different process plan for the very same part, Second, process; planning is developed with the existing configuration of machine tools in mind. Over time, the addition of new equipment will change the suitability of existing plans. Rarely are alterations to old process plans made. One company reportedly had 477 process plans developed for 523 different gears. A close look revealed that more than 400 of the plans could be eliminated. Process planning using CAPP can avoid these problems.Process planning with CAPP takes two different forms;With variant-based planning, one standardized plan and possibly one or more alternate plans is created and stored for each part family. When the planner enters the GT code for a part, the computer will retrieve the best process plan. If none exists, the computer will search for routings and operations for similar parts. The planner can edit the scheme on the CRT screen before printout.With generative planning, which can but does not necessarily rely on coded and classified parts, the computer forms the process plan through a series of questions the computer poses on the screen. The end product is also a standardized process plan, which is the best plan for a particular part.The variant-based approach relied on established plans entered into the computer memory, while the generative technique creates the process plans interactively, relying on the same logic and knowledge that a planner has. Generative process planning is much more complex than variant-based planning; in fact, it approaches the art of artificial intelligence. It is also much more flexible; by simply changing the planning logic, for instance, engineers can consider the acquisition of a new machine tool. With the variant-based method, the engineers must look over and possibly correct all plans that the new tool might affect.CAPP permits creation and documentation of process plans in a fraction of the time it would take a planner to do the work manually and vastlyreduces the number of errors and the number of new plans that must be stored. When you consider that plans normally are handwritten and that process planners spend as much as 30% of their time preparing them, CAPP’S contribution of standardized formats for plans and more readable documents is important. CAPP, in effect, functions as advanced text editor. Furthermore, it can be linked with an automated standard data system that will calculate and record the run times and the setup times for each operation.CAPP can lead to lower unit costs through production of parts in an optimal way. That is, cost savings come not only via more efficient process planning but also through reduced labor, material, tooling, and inventory costs.GT can help in the creation of programs that operate numerically NC machinery, n area related to process planning. For example, after the engineers at Otis Engineering had formed part families and cells, the time to produce a new NC tape dropped from between 4 and 8 hours to 30 minutes. The company thereby improved the potential for use of NC equipment on batches with small manufacturing quantities.编者：吴非晓等《机械英语2》外语教学与研究出版社2002.7译文：成组技术在当今的制造环境下，尤其是对批量生产来说，成组技术（GT）是一个很重要的生产方式而且它正变得越来越重要。

利用CAD / CAM/ CAE系统开发操纵机器人H.S.李*，S.E.张华为技术学院，电力机械工程，云林，台湾，中国摘要在这项研究中，需要开发用于机器人操作臂的CAD/CAE/CAM集成系统。

通过变换矩阵，利用D-H坐标系变换方法对机器人的位姿进行分析，我们使用MATAB软件对其进行计算。

一般来说，利用PRO/E对机械臂的参数进行实体化建模，用Pro / Mechanical软体模拟动态仿真和工作空间，MasterCAM用来实现切削模拟仿真，而最终的模型用CNC数控铣床制造出来。

这样，一个用于机器人操作臂的CAD/CAE/CAM集成系统便开发出来了。

我们用一个范例来验证这种设计，分析以及制造的结果的正确性。

该集成系统不仅促进机器人的生产自动化功能，而且还简化了机械臂的CAD / CAE / CAM的分析过程。

这种集成系统是用于开发一个实用的计算机辅助机构设计课程的教学辅助工具。

©2003由Elsevier B.V.出版关键词：CAD / CAE/ CAM;机械臂;Denavit，Hartenberg坐标系变换引言许多研究已涉及到的CAD / CAE/ CAM集成系统的原理。

吕[1]讨论了平面五杆受电弓的运动学分析并设计制造了基于此弓的机械手。

通过研究五杆受电弓的运动性能，设计出一款简单的控制器来对机械手进行控制。

李某和陈某[2]描述了一个自动升降轮椅固定装置内的全尺寸货车的开发。

开发的过程中，包括机制的概念设计，运动仿真，工程分析，原型开发和测试。

周[3]使用参数化CAD系统的实体模型表达设计理念。

首先开发的是模具，其次是基于CAM系统的模型。

通过与产业界的合作，对试模调整，粉末形成，烧结，烧结后处理在专业的粉末冶金工厂进行了实验。

徐[4]在UG2通用CAD / CAM系统的基础上通过将注塑模具的CAD/CAM软件与注塑模具CAE软件集成建立了一个注塑用CAD / CAE/ CAM系统。

机械制造专业英语文章篇一:机械专业英语文章中英文对照Types of Materials材料的类型Materials may be grouped in several ways. Scientists often classify materials by their state: solid, liquid, or gas. They also separate them into organic (once living) and inorganic (never living) materials.材料可以按多种方法分类.科学家常根据状态将材料分为:固体.液体或气体.他们也把材料分为有机材料(曾经有生命的)和无机材料(从未有生命的).For industrial purposes, materials are divided into engineering materials or nonengineering materials. Engineering materials are those used in manufacture and become parts of products.就工业效用而言,材料被分为工程材料和非工程材料.那些用于加工制造并成为产品组成部分的就是工程材料.Nonengineering materials are the chemicals, fuels, lubricants, and other materials used in the manufacturing process, which do not become part of the product.非工程材料则是化学品.燃料.润滑剂以及其它用于加工制造过程但不成为产品组成部分的材料.Engineering materials may be further subdivided into: ①Metal ②Ceramics ③Composite ④Polymers, etc.工程材料还能进一步细分为:①金属材料②陶瓷材料③复合材料④聚合材料,等等.Metals and Metal Alloys金属和金属合金Metals are elements that generally have good electrical and thermal conductivity. Many metals have high strength, high stiffness, and have good ductility.金属就是通常具有良好导电性和导热性的元素.许多金属具有高强度.高硬度以及良好的延展性.Some metals, such as iron, cobalt and nickel, are magnetic. At low temperatures, some metals and intermetallic compounds become superconductors.某些金属能被磁化,例如铁.钴和镍.在极低的温度下,某些金属和金属化合物能转变成超导体.What is the difference between an alloy and a pure metal? Pure metals are elements which come from a particular area of the periodic table. E_amples of pure metals include copper in electrical wires and aluminum in cooking foil and beverage cans.合金与纯金属的区别是什么?纯金属是在元素周期表中占据特定位置的元素.例如电线中的铜和制造烹饪箔及饮料罐的铝.Alloys contain more than one metallic element. Their properties can be changed by changing the elements present in the alloy. E_amples of metal alloys include stainless steel which is an alloy of iron, nickel, and chromium; and gold jewelry which usually contains an alloy of gold and nickel.合金包含不止一种金属元素.合金的性质能通过改变其中存在的元素而改变.金属合金的例子有:不锈钢是一种铁.镍.铬的合金,以及金饰品通常含有金镍合金.Why are metals and alloys used? Many metals and alloys have high densities and are used in applications which require a high mass-to-volume ratio.为什么要使用金属和合金?许多金属和合金具有高密度,因此被用在需要较高质量体积比的场合.Some metal alloys, such as those based on aluminum, have low densities and are used in aerospace applications for fuel economy. Many alloys also have high fracture toughness, which means they can withstand impact andare durable.某些金属合金,例如铝基合金,其密度低,可用于航空航天以节约燃料.许多合金还具有高断裂韧性,这意味着它们能经得起冲击并且是耐用的What are some important properties of metals?Density is defined as a material’s mass divided by its volume. Most metals have relatively high densities, especially compared to polymers.金属有哪些重要特性?密度定义为材料的质量与其体积之比.大多数金属密度相对较高,尤其是和聚合物相比较而言.Materials with high densities often contain atoms with high atomic numbers, such as gold or lead. However, some metals such as aluminum or magnesium have low densities, and are used in applications that require other metallic properties but also require low weight.高密度材料通常由较大原子序数原子构成,例如金和铅.然而,诸如铝和镁之类的一些金属则具有低密度,并被用于既需要金属特性又要求重量轻的场合.Fracture toughness can be described as a material’s ability to avoid fracture, especially when a flaw is introduced. Metals can generally contain nicks and dents without weakening very much, and are impact resistant. A football player counts on this when he trusts that his facemask won’t shatter.断裂韧性可以描述为材料防止断裂特别是出现缺陷时不断裂的能力.金属一般能在有缺口和凹痕的情况下不显著削弱,并且能抵抗冲击.橄榄球运动员据此相信他的面罩不会裂成碎片.Plastic deformation is the ability of bend or deform before breaking. As engineers, we usually design materials so that they don’t deform under normal conditions. You don’t want your car to lean to the east after a strong west wind.塑性变形就是在断裂前弯曲或变形的能力.作为工程师,设计时通常要使材料在正常条件下不变形.没有人愿意一阵强烈的西风过后自己的汽车向东倾斜.However, sometimes we can take advantage of plastic deformation. The crumple zones in a car absorb energy by undergoing plastic deformation before they break.然而,有时我们也能利用塑性变形.汽车上压皱的区域在它们断裂前通过经历塑性变形来吸收能量.The atomic bonding of metals also affects their properties. In metals, the outer valence electrons are shared among all atoms, and are free to travel everywhere. Since electrons conduct heat and electricity, metals make good cooking pans and electrical wires.金属的原子连结对它们的特性也有影响.在金属内部,原子的外层阶电子由所有原子共享并能到处自由移动.由于电子能导热和导电,所以用金属可以制造好的烹饪锅和电线.It is impossible to see through metals, since these valence electrons absorb any photons of light which reach the metal. No photons pass through.因为这些阶电子吸收到达金属的光子,所以透过金属不可能看得见.没有光子篇二:机械专业英语作文1Mechanical engineeringEngineering Science in life are widely used, especially in mechanical engineering in the application of life is almost throughout life in all its aspects, to automobiles, aircraft, small electric fans, umbrella, all of these and related machinery. The project includes many subjects, but the mechanical engineering is one of the most important subjects, not only because of our life and it is closely related to, but with the progress of the times, people have to rely on mechanical engineering products, in automation today, machine instead of many this is the part of the human labor, improve the efficiency and save time.As a result of mechanical engineering in every aspect of life, therefore, as an engineer, be faced with a great many challenges, inaddition to a solid with knowledge, but also keep pace with the times, familiar with the machinery and related software, can be very good use of software, and as a an engineer, we should try our best to design and produce and closely related to the life of the machine, and can in life play a real role, also have only such, we address and remission now social needs, therefore, the mechanical engineering in the future social development, will play the important role, especially China s case, the industry also is not very developed, machinery can be greater development space.Before the industrial revolution, machinery is mostly wood structure, wood made by hand by. The development of social economy, the demand for mechanical products. The bulk of the production increasing and precision processing technology progress, promote the mass production method ( interchangeability of parts production, professional division of labor and cooperation, water processing lines and assembly lines ) formation. Study of mechanical products in the manufacturing process, especially when used in the pollution of the environment and natural resources e_cessive consumption problems and their treatment measures. This is a modern mechanical engineering is an especially important task to grow with each passing day, and its importance.Application of mechanical products. This includes selection, ordering, acceptance, installation, adjustment, operation, maintenance, repair and transformation of the industrial use of machinery and complete sets of machinery and equipment, to ensure that the mechanical products in the long-term use of reliability and economy. As a student, we are now the most important to learn professional knowledge, only in this way, can we later life and learning, to do its part.机械工程工程科学在生活中应用广泛,特别是机械工程在生活中的应用几乎就是遍布了生活中的各个方面,大到汽车.飞机,小到电风扇.雨伞,这些都和机械有关.工程包括很多科目,但是机械工程是最重要的科目之一,不仅是因为它和我们的生活关系密切,而是随着时代的进步,人们已经依赖上机械工程制造出来的产品,而在自动化的今天,机器代替了许多本该是人类该做的部分劳动,提高了效率和节约了时间.由于机械工程遍布了生活的每一个方面,因此,做为一个工程师,要面临很大且很多的挑战,除了要具备扎实的装也知识外,还要与时俱进,熟悉和机械有关的软件,并要能很好的运用软件,而作为的一个工程师,我们要尽量设计和制造出和生活密切相关的机器,并能够在生活中起到真正的作用,也只有这样,我们解决和缓解现在社会上的需要,因此,机械工程在今后的社会的发展中,还是会起这重要的作用,特别是我国的这样的情况,工业还不是很发达的情况下,机械可发展的空间更大.工业革命以前,机械大都是木结构的,由木工用手工制成.社会经济的发展,对机械产品的需求猛增.生产批量的增大和精密加工技术的进展,促进了大量生产方法（零件互换性生产.专业分工和协作.流水加工线和流水装配线等）的形成.研究机械产品在制造过程中,尤其是在使用中所产生的环境污染和自然资源过度耗费方面的问题及其处理措施.这是现代机械工程的一项特别重要的任务,而且其重要性与日俱增.机械产品的应用.这方面包括选择.订购.验收.安装.调整.操作.维护.修理和改造各产业所使用的机械和成套机械装备,以保证机械产品在长期使用中的可靠性和经济性.做为学生,我们现在最重要的学好专业知识,只有这样,我们才能以后是生活和学习中,才能尽自己的一份力量.篇三:机械类专业英语课文参考翻译_pdf第一课该○翻译整理于网络,It is known that metals are very important in our life. Metals have the greatest importance for industry. All machines and other engineering[7endVi5niEriN] constructions have metal[5metl] parts; some of them consistonly of metal parts.众所周知,金属在我们的生活中是非常重要的,金属对于工业而言是有巨大的重要性,所有机器和其他工程构造都有金属零部件,其中一些还只能由金属组成.There are two large groups of metals:1) Simple metal- more or less pure chemical elements[5elimEnt]2) Alloys[5AlCi]- materials consisting of a simple metal combined with some other elements.有两大类金属:（1）纯金属——或多或少的金属元素（2）合金——组成纯金属的原料结合其他元素.About two thirds of all elements found in the earth are metals, but not all metals may be used in industry. Those metals which are used in industry are called engineering metals. The most important engineering metal is iron[5aiEn], which in the form of alloys with carbon[5kB:bEn] and other elements, finds greater use than any other metal. Metals consisting of iron combined with some other elements are known as ferrous[5ferEs] metals; all the other metals are called nonferrous[5nCn5ferEs] metals. The most importantnonferrous metal are copper[5kCpE], aluminum[E5lju:minEm], lead[li:d], zinc[ziNk], tin[tin], but all these metals are used much less than ferrous metals, because the ferrous metals are much cheaper.第 _._._._. 在地球上发现的所有元素中,大约三分之二是金属元素,但是并不是所有的金属都能够用于工业上.那些金属—我们用于工业上的金属—被称为工程金属,最重要的工程金属那就是铁,铁跟碳和其他元素结合形成合金的那些金属比其他金属发现有更大用途.铁与别的其他某些元素相结合而组成的金属称为黑色金属,此外所有其他金属都称为有色金属,最重要的有色金属是---铜,铝.铅.锌.锡.但是使 _课的翻译暂时没有. 用这些有色金属比使用黑色金属要少的多,因为黑色金属便宜得多.Engineering metals are used in industry in the form of alloys because the properties[5prCpEti] of alloys are much better than the properties of pure[pjuE] metals. Only aluminum may be largely used in the form of simple metal. Metals have such a great importance because of their useful properties or their strength, hardness, 翻译标准.请放心使 and their plasticity[plAs5tisiti].因为合金的特性比纯金属的好,所以工程金属以合金的形式用于工业,只有铝以纯金属的形式被广泛应用.金属因为具有强度.硬度和可塑性而发挥着特别重要的作用. 用.Different metals are produced in different ways, but almost all the metal are found in the forms of metal ore[C:(r)] (iron ore, copper ore, etc[et cetra].)以不同的方法生产不同的合金但是几乎所有的金属都是以金属矿的形式（铁矿.铜矿）被发现的.The ore is a mineral[5minErEl] consistence of a metal combined with some impurities[im5pjuEriti]. Inorder to produce a metal from some metal ore, we must separate these impurities from the metal that is done by metallurgy[me5tAlEdVi].矿石是一种由金属与某些杂质相混合而组成的矿物质,为了用金属矿石来生产出一种金属,我们必须把杂质从金属矿中分离出去,那就要靠冶炼来实现. Te_t:12. Plastics and Other MaterialsTe_t:Plastics[5plAstik, plB:stik] have specific properties which may makeik] acids[5AsId], such as sulphuric[sQl5fjuErik] acid and hydrochloric[7haidrEu5klC:rik] acid. Plastics tend to be resistant to these acids, but can have dissolved or deformed by solvent[5sClvEnt], suchas carbon tetrachloride[7tetrE5klC:raid], which have the same carbon base as the plastics. Color must be applied to the surface of metals, whereas it can be mi_ed in with plastics. Metals are more rigid[5ridVid] than most plastics while plastics are very light, with a specific[spi5sifik] gravity normally between 0.9 and 1.8. Most plastics do not readily[5redili] conduct[5kCndQkt] heat or electricity[Ilek5trIsItI]. Plastics soften slowly and can easily be shaped[Feip] when they are soft.塑料具有特殊的性能.对于某种用途而言,这些性能使得塑料比传统材料更为可取.例如,跟金属相比较,塑料既有优点也有缺点.金属易受到无机酸的腐蚀,如硫酸和盐酸,塑料能抵抗这些酸的腐蚀,但可被溶剂所洛解或引起变形,例如溶剂四氯化碳与塑料具有同样的碳基.颜色必定只能涂到金属的表面.而它可以跟塑料混合为一体.金属比大多数塑料刚性要好,而塑料则非常之轻,通常塑料密度在0. 9-1. 8之间.大多数塑料不易传热导电.塑料能缓慢软化,而当其还是在软的状态时,能容易成形.It is their plasticity[plAs5tisiti] at certain temperatures[5temprItFE(r)] which gives plastics their main advantages over many other materials. It permits the large-scale production of molded[mEuld] articles, such as containers, at an economic unit cost, where other materials require laborious[lE5bC:riEs] and often costly processes involving cutting, shaping, machining, assembly[E5sembli] and decoration.在某一温度下塑料是处于塑性状态的,这就使塑料具备超过许多其他材料的主要优点.它容许大量生产单位成本低廉的模制式器件,例如,各种容器.于此,若用其他材料则需要大量劳力和往往需要很费钱的加工工艺,比如,切割.成形.加工.装配和装饰.Plastics not only replace other materials. Their properties can be e_ploited[iks5plCit] for entirely[In5taIElI] new applications. For e_ample, plastics heart valves[vAlv] and other human spare parts have make possible many recent developments in surgery[5sE:dVEri].塑料不仅可以代替其他材料,而且它的特性能被开拓应用于全新领域,比如:随着最近外科手术的发展可能做成塑料的心脏瓣膜和其他人类的器官.There is no single plastics material which is suitable for all applications. It is important that the most suitable plastics should be chosen, and if necessary adapted[E5dApt], for each particular requirement. It is also important that the properties of the plastics chosen should be e_ploited to the best advantage.没有一种纯塑料材料适用于各个领域,如果有必要改进,对于每个有特殊要求的来说选择最合适的塑料是最重要的,被选择的塑料材料的特性被开拓得到更好的应用也是很重要的.A plastics article may need to differ in design and appearance from a similar article made from another material such as metal or wood. This is due[ ] not only to the properties of plastics but also to thetechniques[tek5ni:k] employed in fabricating[5fAbrikeit] plastics. These techniques include injection[in5dVekFEn] molding[5mEuldiN], blow molding, compression molding, e_trusion[eks5tru:VEn] and vacuum[5vAkjuEm] forming.塑料器件可能需要用其他材料比如:与金属或木材制作的类似的器件从设计和外观上加以区别,这不仅是由于塑料性能不同的原因,也是由于制造塑料产品所用的技术不同所致,这些技术包括:注塑.模制.吹塑模制.压模.挤压和真空成型等.23. Casting and Die-Casting AlloysTe_t:Casting[5kB:stiN] is one of the oldest metal working techniques known to man. Our country made metal castings as early as _ B.C., and the process used then is not much different in principle[5prinsEpl] from the one used today.铸造是入类所掌握的最古老的金属加工技术之一.我国早在公元前 _年就已把金属制成铸件,而所使用的工艺从原理上和今天的工艺没有多大的区别.Foundry[5faundri]processesconsistof makingmolds,preparingandmelting[melt]themetal, pouring[pC:, pCE] the metal into the molds, and cleaning the castings. The product of the foundry is a casting, which may vary from a fraction[5frAkFEn] of a kilogram to several hundred tons. It may also vary in composition[kCmpE5ziFEn] as practically all metals and alloys can be cast.铸造工艺由制模.备料和金属熔炼,金属液浇注入模和铸件清砂等.铸造的产品是铸件,铸件可能从零点几公斤到几百吨范围变化.实际上所有金属在成分上也是变化的,而合金也可以铸造.The metals most frequently cast are iron, steel, aluminum and so on. Of these, iron, because of its low melting point, low price and ease of control, is outstanding for its suitability[9sjU:tE`bIlEtI] for casting and is used far more than all the others.最常铸造的金属是铸铁.钢.铝等等.这些金属中,铸铁,由于其低熔点,低价格和易控制,因而其铸造适应性是最突出的,而且使用也远比所有其他金属多.Castingisawidelyusedmethodofproducingmetalproducts,particularlythosew hichareintricate[5intrikit]. Since molten materials will readily take the shape of the container into which they are poured, it is nearly as easy to cast fairly comple_ shapes as to produce simple forms.由于熔融的物料能容易取得被浇注进去的容器（模型）的形状,因此,几乎像生产简单形状铸件那样颇为容易地铸造出复杂形状的铸件.The place where the metals are cast is called a foundry. The most important of cast metals is cast iron which is made from pig iron by remelting it in a special melting furnace[5fE:nis] called a cupola[5kju:pElE].铸造金属的地方叫做铸造车间.最重要的铸造金属是铸铁,铸铁是用生铁在一个特殊的熔炉—叫冲天炉的炉子中重新熔炼而制造出来的.From the cupola, the cast iron flows into ladles[5leidl] of different size, and from these ladles it is poured into the molds.从冲天炉中出来的铁水流入到不同规格的铁水包中,并从这些铁水包中被浇注到模型中.The molds may be of two kinds: sand molds and metal molds. A metal mold consists of two hollow parts which should be joined for pouring the metal into it. The inside of this mold is covered with carbon or graphite[5 Afait] so that the metal could not stick[stik] to the wall of the form. When the metal has solidlocks of steel produced by pouring the metal into these molds are called ingots and the process is called ingot casting.模型有两种类型:砂模和金属模.金属模是由两个中空的部件组成,它们应被联结在一起以便将金属液浇入模箱中.这模腔的内侧是要涂以碳粉或石墨,因此金属不玫于粘贴到型腔壁上口当金属液凝固后,这中空的型箱部件被打开并取出铸件.也有一种特殊模型,在该模型中可以铸造大型钢块.这些模型通常用铸铁米制造,并被称为锭模.而浇注金属液到这些模子中生产出的钢块被称为钢锭.该工艺过程叫锭铸.A relatively[5relEtIvlI] wide range of nonferrous alloys can be die-cast. The principal base metals used, in order to commercial importance, are zinc, aluminum, copper, magnesium[mA ni:zjEm], lead, and tin. The alloys may be further classified as low-temperature alloys and high-temperature alloys; those having a casting 3temperature below 538C, such as zinc, tin, and lead, are in the low-temperature class. The low-temperature alloys have the advantages of lower cost of production and lower die-maintenance[5meintinEns] costs. As the casting temperature increases, alloy and other special steels in the best treated condition are required to resist the erosion[i5rEuVEn] and heat checking[5tFekiN] of die surface. The destructive[dis5trQktiv] effect of high temperaturesonthedies hasbeentheprincipalfactorinretarding[ri5tB:d] thedevelopmentof high-temperature die castings.相当大量的有色金属合金可以进行模铸}h 用的主要而基本的金属,按其在工业上应用的重要性的顺序是锌.铝.铜.锰.铅和锡.这些合金可以进一步进行分类为低温类合金和高温类合金.铸造温度低于538℃的那些合金,就像锌.锡和铅,是属于低温类合金.低温类合金具有低生产成本和低的模具维修费用等优点.当铸造温度上升时,需要最佳条件下处理过的合金钢和其他特种钢来抵抗腐蚀及防止模具表面的热裂纹.高温在模具上的损坏作用已经成为阻碍.延缓高温模铸发展的主is more pronounced[pr5naunst] with some alloys than with others. Aluminum, in particular, has a destructive action on ferrous metals and, for this reason, is seldom melted in the machine, whereas the copper-basealloys are never melted in the machine.控制选择合金的另外一个因素就是熔融的金属在相关的机器零件上和模具上的腐蚀或溶解作用.这种作用随着温度的升高而增加,甚至某些合金比另一些合金更为明显.特别是 .铝对黑色金属有一种破坏作用,为此.铝几乎不熔混于机器零件中,而铜基合金是决不能熔混于机器构件中的.44. ForgingTe_t:Press forging[5fC:dViN] employs a slow squeezing[skwi:z] action in deforming[di:5fC:m] the plastic metal, as contrasted with the rapid-impact[5impAkt] blows of a hammer. The squeezing action is carried completely to the center of the part being pressed, thoroughly working the entire section[5sekFEn]. These presses are the vertical[5vE:tikEl] type and may be either mechanically[mi5kAnikEli] or hydraulically[hai5drC:lik] operated. The mechanical presses, which are faster operating and most commonly used, range in capacity[kE5pAsiti] from 5_ to 1_0 tons.与锤锻的快速冲击不同,压力机锻造是用缓慢的挤压作用使塑性金属变形.这挤压作用完全被施加到正在被压锻的零件中心位置上,直至彻底使整个工件得到加工.这些压力机都是立式的,可能是机械操作也可能是液压操作的.机械操作压力机,操作速度比较快,使用最普遍,锻造能力从 5_吨到1__吨范围.For small press forgings, closed impression dies are used and only one stoke of the ram[rAm] is normally required to perform[pE5fC:m] the forging operation. The ma_imum[5mAksimEm] pressure is built up at the endof the stroke which forces the metal into shape. Dies may be mounted[maunt] as separate units, or all the cavities may be put into single block. Forsmall forgings, individual[7indi5vidjuEl] die unites are more convenient. There is some difference in the design of dies for different metals; copper-alloy forgings can be made withless draft[drB:ft] than steel,consequently more complicated[5kCmplikeitid]shapes can be produced. These alloys flow well in the die and are rapidly e_truded 对于小型压力锻使用闭式锻模.通常要求锻锤仅一个冲程就完成锻造工艺.在冲程终端产生最大压力,该冲击压力迫使金属成形.模具可由各白独立的单元装配而成,即把所有个别模腔都放到一起,组成整体.对于小型锻件使用分模装置更为方便.对于不同的金属在模具设计上有些区别 .铜合金锻件比钢件用较小的拔模斜度,因此可生产更加复杂形状的锻件.这些合金在该种模具中流动性好,而且能快速挤压成形.In the forging press, a greater proportion of the total work put into the machine is transmitted[trAnz5mit] to the metal than in a drop hammer press. Much of the impact of the drop hammer is absorbed by the machine and foundation. Press reduction of the metal is faster, and the cost of operation is consequently lower. Most press forgings are symmetrical[si5metrikEl] in shape, having surfaces which are quite smooth, and provide a closer tolerance[5tClErEns] than is obtained by a drop hammer. However, many parts of irregular[i5re…ulE] and complicated shapes can be forged more economically by drop forging. Forging press is often used for sizing operations on parts made by other forging processes.锻压机比落锤锻,输入到机器里的总能量中有更大部分的能量被传输到金属坯料上.落锤锻的冲击能量被机器和基础吸收得较多(比起压力机来〕.金属上的压力衰减较快,因此生产成本比较低.大多数压力锻锻件形状.产生的表面都是对称的,而且表面非常光滑,并比落锤锻件的公差尺寸更加精确.然而落锤锻造可以锻制形状复杂而不规则的锻件,因而较为经济.锻压机常常用来为其他锻造工艺所生产的锻件进行整形和校正加工用.In drop forging, a piece of metal, roughly[5rQflI] or appro_imately of the desired[di5zaiE] shape, is placed between die faces having the e_act form of the finished piece, and forced to take thin form by drawing the dies together. Large ingots are now almost always forged with hydraulic presses instead of with steam hammers, sinc。

机械类英语论文及翻译Mechanical design involves the n of machines。

which are composed of mechanisms and other components that can transform and transmit ___ machines include engines。

turbines。

vehicles。

hoists。

printing presses。

washing machines。

and ___ and methods of design that apply to machines also apply to ___。

the term "mechanical design" is used in a broader sense than "machine design" to include their design.When ___。

___ to take into account。

The n and structural aspects of the device。

as well as the ___。

___ apply not only to machines but also to other mechanical devices。

such as switches。

cams。

valves。

vessels。

and mixers.Mechanical design is a critical field in ___ disciplines。

It plays an essential role in the ___ the success of a mechanical design project。

it is essential to follow a set of rules for design。