机械专业毕业设计外文翻译
锻造、铸造、焊接外文翻译
毕业设计(论文)外文翻译学生姓名：系别：机械工程系专业：机械设计制造及其自动化班级：学号:译文出处：Science and Technology Engl-ish for Mechanical EngineeringCasting、Forging and Welding1. CastingMetal casting is one of the oldest of all industries, both ancient and medieval history offering examples of the manufacture and use of casting. From simple axeheads poured from copper in open moulds some 5000 years age, casting in the pre-Christian world developed to a point at which elaborate bronze statuary could be produced in two-piece and cored moulds. By the end of the medieval period, decorated bronze and pewter casting had begun to be used in European church and domestic life.The widespread adoption of cast iron as engineering material awaited the success of Abraham Darby in 1790 in smelting in the coke blast furnace; this paved the way for the massive use of cast iron in construction during the years following the industrial revolution.Many foundries sprang up after the industrial revolution, the vast majority being for the manufacture of the cast iron then being used as a structural material. The quantity production of iron castings in the nineteenth century was not matched by a universal advance in quality and the engineering use of the products encountered more serious risks in a non-ductile material.Despite the skill of the molder in producing complex forms, there was little change in the metallurgical and engineering situation until the modern era brought a better understanding of the factors determining quality. With modern techniques of process control the rudimentary judgment of the operator could give way to objective measurements of metal temperature, molding material properties and other production variables. These improvements have been applied not only to cast iron but to a wide range of cast alloys.There are four basic casting methods: sand-casting, die-casting, investment-casting, and centrifugal casting.Sand-casting is the most widely used method employed in foundry. In this process, sand moulds are contained in metal molding boxes that have four sides but no top or bottom. During the molding operation the boxes are located togetherby pins so that they can be separated to remove the pattern, and replaced in the correct position before the metal is poured in. The boxes are clamped together, or the cope (top section) weighted down when pouring to prevent the cope from “floating away”from the drag (lower section) when the mould is full of molten metal. The sequence when molding the simple two-part mould to cast a bracket is illustrated as follows.At the first stage the pattern is seated on the moulding board. The pattern is covered with facing sand, which is a specially prepared sand of good quality, which can take a clean and smooth impression, and can resist the heat from the molten metal that will be in contact with it. The facing sand is backed up with molding sand, which is old facing sand from previous moulds. The molding sand is carefully rammed up so that it is fairly tight around the pattern to produce a good solid mould, yet permeable enough to allow the gases produced during casting to escape. The sand is finally leveled off.At the second stage the mould with the pattern still in position is inverted; the exposed sand lightly covered with parting sand, and the exposed pattern with facing sand.(The parting sand has no cohesion, and is introduced to permit a clean separation when the mould is opened up to remove the pattern .) The second molding box is located in position on the first box and filled with molding sand. Two or more plugs are introduced when the second box is being filled (these are removed later, leaving channels in the sand). One of these plugs is positioned to one side of the pattern. The sand is rammed up and leveled off.Now, at stage 3, to allow the pattern to be removed. This is done by screwing a bar with a threaded end into a suitable insert in the pattern, damping the sand around the pattern, and gently rapping the bar in all directions so that the pattern can be carefully withdrawn. To facilitate the removal of the pattern without scuffing the sides of the impression, all surfaces that lie in the direction of pattern removal are inclined slightly by a small amount (the draw angle).A groove called a gate is cut in the sand face to allow the channel producedby the plug that is outside the pattern to connect with the impression .The metal is poured through this channel (called the runner), and the gate prevents it from dropping straight into the impression and damaging it .The cross-section of the gate is slightly smaller than that of channel so that a full runner will always supply metal to the gate at a slight pressure.Finally, the mould is reassembled, carefully locating and securing the two sections. The top section is known as the cope, and the lower section is known as the drag. The sand in the cope is vented. These vents allow the sand to be rammed up more tightly at the earlier stages without the risk of gases being trapped in the molten metal and forming blowholes in the solid metal. A sand-feeding gate (also called a pouring or bowl) is added to make it easier to pour the metal into the runner. The molten metal is poured through the runner and the air will escape through the riser.The impression will be filled with molten metal when it is completely filled. Gases can escape through the runner and the riser, which also act as headers to supply the impression with more metal to compensate for the contraction of the metal when cooling in the molten state.2. ForgingForging is the plastic working of metal by means of localized compressive forces exerted by manual or power hammers, presses, or special forging machines. It may be done either hot or cold. however, when it is done cold, special names usually are given to the processes. Consequently, the terms“forging” usually implies hot forging done above the recrystallization temperature.Modern forging is a development form the ancient art practiced by the armor makers and the immortalized village blacksmith. High-powered hammers and mechanical presses have replaced the strong arm, the hammer, and the anvil and modern metallurgical knowledge supplements the art skill of the craftsman in controlling the heating and handling of the metal.Forge ability is the term used in the industry to denote a material relative resistance to deformation and its plasticity. While considerable disagreementexists as to precisely what characteristics the word “forge ability” should include, the term as used here is defined as the tolerance of a metal or alloy for deformation without failure, regardless of forging pressure requirements.Raw material used for forging is generally bar or billet stock hot rolled from ingots melted in open-hearth, electric arc, or vacuum arc furnace .other forms and shapes such as rolled slabs, plats, and stock produced by continuous casting techniques are occasionally used .for certain grades ,vacuum arc melting imparts better forge ability than does conventional arc melting . However, the major purpose of vacuum melting is the improvement of mechanical properties and cleanliness, not forging behavior.Equipment behavior influences the forging progress since it determines the feasibility of forging a part and affects the rate of deformation and the temperature conditions.The hammer is the most economical type of equipment for generating load and energy necessary to carry out a forging process, provided that the material being forged can support high deformation velocities. It is most commonly used hot forging equipment for repeated blows on the same workpiece and cannot be overloaded.There are various types of hammers: air-lift gravity drop hammers, power drop hammers, power drop hammers, Counterblow hammers ect. In a simple gravity drop hammer the upper ram is positively connected to a board, a belt, a chain or a piston. When forging the ram is lifted to a certain height and then dropped on the stock placed on the anvil. During the down stroke, the rain is accelerated by gravity and builds up the blow energy. The upstroke takes place immediately after the blow, the force necessary to ensure quick lift-up of the ram can be 3 to 5 times the ram weight. The operation principle of a power-drop hammer is similar to that of an air drop hammer. During the down stroke, in addition to gravity, the ram is accelerated by steam, cold air or hot air pressure. In an electro hydraulic gravity-drop hammer, the ram is lifted with oil pressure against an air cushion. The compressed air slows down the upstroke of the ram and contributes to its acceleration during the down stroke .thus; the electrohydraulic hammer also has a minor power hammer action.Press forging employs a slow squeezing action in deforming the plastic metal, as contrasted with the rapid-impact blows of a hammer. Hydraulic forging press is operated by large pistons driven by high-pressure hydraulic or hydrometric system. The squeezing action is carried completely to the center of the part being pressed, thoroughly working the entire section. These presses are the vertical type and may be either mechanically or hydraulically operated. The mechanical presses, which are faster operating and most commonly used, range in capacity from 5000 to 10000 tons.In the forging press a grater proportion of the total work put into the machine is transmitted to the metal than in a drop hammer. The machine and foundation absorb much of the impact of the drop hammer .press reduction of the metal is faster, and the cost of operation is consequently lower. most press forging s are symmetrical in shape ,having surfaces, which are quite smooth, and provide a closer tolerance than is obtained by a drop hammer .however ,drop forging can forge many parts of irregular and complicated shapes more economically. Forging presses are often used for sizing operations on parts made by other forging processes.For small forgings closed impression dies are used, and only one stroke of the ram is normally require to perform the forging operation .the maximum pressure is built up at the end of the stroke ,which forces the metal into shape .dies may be mounted as separate units, or all the cavities may be put into a single block. for small forgings individuals die units are more convenient .large ingots are now almost always forged with hydraulic presses instead of with steam hammers, since the work done by a press goes deeper. Further, the press can take a cooler ingot and can work to closer dimensions.The forging should be done at about the same temperature as rolling; the process improves the physical properties of the steel just as rolling does. In the final forging it is important not to have the steel too hot, for overheated steel will have poor mechanical properties when cooled. in heating for forging the temperature is usually judged by the eye, but where a large number of thesame patterns will be made, the pieces to be forged are heated in furnaces in which the temperature is indicated by pyrometers, and often is automatically controlled.3. weldingWelding techniques have become so versatile that it is difficult nowadays to define “welding”. Formerly welding was “the joining of metals by fusion”, that is, by melting, but this definition will no longer do. Welding was next defined as the “joining of metals by heat”, but this is not a proper definition either. Not only metals can be welded, so can many of the plastics. Furthermore several welding methods do not require heat. Every machinist is familiar with heatless welding method under some circumstances. Besides these, we can weld with sound and even with the famous laser. Faced with a diversity of welding methods that increase year by year, we must here adopt the following definition of welding:" welding is the joining of metals and plastics by methods that do not employ fastening devices”.There is also no uniform method of naming welding processes. Some processes are named according to the heat source or shielding method, other certain specialized processes are named after the type of joint produced. Examples are spot and butt welding. But an overall classification can not take account of this because the same type of joint may be produced by a variety of processes. Spot welding may be done by electric resistance, arc, or electron-beam processes and butt welding by resistance, flash or any of a number of other methods. Many welding processes are named depending on the heat applied, equipment used, and type of metal to be joined and the strength of the joint.Soldering is the process of joining two metals by a third metal to be applied in the molten state. Solder consists of tin and lead, while bismuth and cadmium are often included to lower the melting point. One of the important operations in soldering is that of cleaning the surface to be joined, this may be done by some acid cleaner. Soldering gives a satisfactory joint for light articles ofsteel, copper or brass, but the strength of soldering joint is rather less than a joint which is brazed, riveted or welded. These methods of metal are normally adopted for strong permanent joints.Pressure welding is known as the simplest method of welding two pieces of metal together. The ends of metal are heated to a while heat—for iron, the welding temperature should be about 1300℃—in a flame. At this temperature the metal becomes plastics. The ends are then presses or hammered together, and the joint is smoothed off. Care must be taken to ensure that the surfaces are thoroughly clean first, for dirt will weaken the weld. Moreover, the heating of iron or steel to a high temperature causes oxidation, and a film of oxide is formed on the heated surfaces. For this reasons, a flux is applied to the heated metal. At welding heat, the flux melts, and the oxide Particles are dissolved in it together with any other impurities which may be present. The metal surfaces are pressed together, and the flux is squeezed out from the center of the weld.Gas welding includes all the processes in which gases are used to obtain a hot flame. Those commonly used are acetylene, natural gas, and hydrogen in combination with oxygen. The maximum temperature developed by oxyhydrogen welding is 3600℉ (1980℃). Hydrogen is produced either by the electrolysis of water or by passing steam over coke. An oxyacetylene weld is produced by heating with a flame obtained from the combustion of oxygen and with or without the use of a filler metal. In most cases the joint is heated to a state of fusion, and as a rule, no pressure is used.Are welding is a process in which coalescence is obtained by heat produced from an electric arc. The electrode or filler metal is heated to a liquid state and deposited into the joint to make the weld. Contact is first made between the electrode and the work to create an electric circuit, and then, by separating the conductors, an arc is formed. The electric energy is converted into intense heat in the arc, which attains a temperature around 10 000°F (5500℃). Either direct or alternating current can be used for arc welding, direct current being preferred for most purposes. A d-c welder is simply a motor-generator set ofconstant-energy type, having the necessary characteristics to produce a stable arc. Arc welding uses commonly metal electrodes or carbon electrodes.Laser Welding is used because of laser’s high heat intensity. It can be operated in any transparent medium without contact with the workpiece, since the laser delivers its energy in the form of light. In welding, the power is delivered in pulses rather than as a continuous beam, the beam is focused on the workpiece and the intense heat produces a fusion weld. Laser welding is slow and is used only for special jobs involving small weldments. Its greatest use is found in the electronics industry.Explosion welding is a process that uses energy from the detonation of an explosive to join two pieces of metal. The explosion accelerates the pieces to a speed at which a metallic bond will form between them when they collide. The weld is produced in a fraction of a second without the addition of filler metal. This is essentially a room temperature process in that gross heating of the workpieces does not occur. The faying surfaces, however, are heated to some extent by the energy of the collision, and welding is accomplished through plastic flow of the metal on those surfaces. Welding takes place progressively as the explosion and the forces it creates advance from one end of the joint to the other. Deformation of the weldment varies with the type of joint. There may be no noticeable deformation at all in some weldments, and there is no loss of metal.译文：铸造、锻造和焊接1.铸造金属铸造是最古老的产业之一，远古时期和中世纪就有人使用和制造铸件了。
机械专业毕业设计外文翻译--什么是液压
What is Hydraulic?A complete hydraulic system consists of five parts, namely, power components, the implementation of components, control components, no parts 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 hydraulic pump gears are generally pump, vane pump and piston pump. Implementation of components (such as hydraulic cylinders and hydraulic motors) which is the 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 valves can be divided into the village of force control valve, 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 oildollars. 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.Hydraulic principleIt consists of two cylinders of different sizes and composition of fluid in the fluid full of water or oil. Water is called "hydraulic press"; the said oil-filled "hydraulic machine." Each of the two liquid a sliding piston, if the increase in the small piston on the pressure of a certain value, according to Pascal's law, small piston to the pressure of the pressure through the liquid passed to the large piston, piston top will go a long way to go. Based cross-sectional area of the small piston is S1, plus a small piston in the downward pressure on the F1. Thus, a small piston on the liquid pressure to P = F1/SI,Can be the same size in all directions to the transmission of liquid. "By the large piston is also equivalent to the inevitable pressure P. If the large piston is the cross-sectional area S2, the pressure P on the piston in the upward pressure generated F2 = PxS2Cross-sectional area is a small multiple of the piston cross-sectional area. From the type known to add in a small piston of a smaller force, the piston will be in great force, for which the hydraulic machine used to suppress plywood, oil, extract heavy objects, such as forging steel.History of the development of hydraulicAnd 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 Joseph (Joseph Braman ,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.World War I (1914-1918) after 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. Vikers) 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 Constantine (G • Constantimsco) fluctuations of the energy carried out by passing theoretical and practical research; in 1910 on the hydraulic transmission (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 for nearly 20 years later. Before and after in1955, 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 workers. Plastic processing industry, machinery, pressure 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 the dam gates and devices, bed lifts installations, bridges and other manipulation of institutions; speed turbine power plant installations, nuclear power plants, etc.; ship deck crane (winch), the bow doors, bulkhead valves, such as the stern thruster ; 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.什么是液压？一个完整的液压系统由五个部分组成，即动力元件、执行元件、控制元件、无件和液压油。
机械专业毕业设计外文翻译----高速铣削
英文资料High-speed millingHigh-speed machining is an advanced manufacturing technology, different from the traditional processing methods. The spindle speed, cutting feed rate, cutting a small amount of units within the time of removal of material has increased three to six times. With high efficiency, high precision and high quality surface as the basic characteristics of the automobile industry, aerospace, mold manufacturing and instrumentation industry, such as access to a wide range of applications, has made significant economic benefits, is the contemporary importance of advanced manufacturing technology. For a long time, people die on the processing has been using a grinding or milling EDM (EDM) processing, grinding, polishing methods. Although the high hardness of the EDM machine parts, but the lower the productivity of its application is limited. With the development of high-speed processing technology, used to replace high-speed cutting, grinding and polishing process to die processing has become possible. To shorten the processing cycle, processing and reliable quality assurance, lower processing costs.1 One of the advantages of high-speed machiningHigh-speed machining as a die-efficient manufacturing, high-quality, low power consumption in an advanced manufacturing technology. In conventional machining in a series of problems has plagued by high-speed machining of the application have been resolved.1.1 Increase productivityHigh-speed cutting of the spindle speed, feed rate compared withtraditional machining, in the nature of the leap, the metal removal rate increased 30 percent to 40 percent, cutting force reduced by 30 percent, the cutting tool life increased by 70% . Hardened parts can be processed, a fixture in many parts to be completed rough, semi-finishing and fine, and all other processes, the complex can reach parts of the surface quality requirements, thus increasing the processing productivity and competitiveness of products in the market.1.2 Improve processing accuracy and surface qualityHigh-speed machines generally have high rigidity and precision, and other characteristics, processing, cutting the depth of small, fast and feed, cutting force low, the workpiece to reduce heat distortion, and high precision machining, surface roughness small. Milling will be no high-speed processing and milling marks the surface so that the parts greatly enhance the quality of the surface. Processing Aluminum when up Ra0.40.6um, pieces of steel processing at up to Ra0.2 ~ 0.4um.1.3 Cutting reduce the heatBecause the main axis milling machine high-speed rotation, cutting a shallow cutting, and feed very quickly, and the blade length of the workpiece contacts and contact time is very short, a decrease of blades and parts of the heat conduction. High-speed cutting by dry milling or oil cooked up absolute (mist) lubrication system, to avoid the traditional processing tool in contact with the workpiece and a lot of shortcomings to ensure that the tool is not high temperature under the conditions of work, extended tool life.1.4 This is conducive to processing thin-walled partsHigh-speed cutting of small cutting force, a higher degree of stability, Machinable with high-quality employees compared to the company may be very good, but other than the company's employees may Suanbu Le outstanding work performance. For our China practice, we use the models to determine the method of staff training needs are simple and effective. This study models can be an external object, it can also be a combination of internal and external. We must first clear strategy for the development of enterprises. Through the internal and external business environment and organizational resources, such as analysis, the future development of a clear business goals and operational priorities. According to the business development strategy can be compared to find the business models, through a comparative analysis of the finalization of business models. In determining business models, a, is the understanding of its development strategy, or its market share and market growth rate, or the staff of the situation, and so on, according to the companies to determine the actual situation. As enterprises in different period of development, its focus is different, which means that enterprises need to invest the manpower and financial resources the focus is different. So in a certain period of time, enterprises should accurately selected their business models compared with the departments and posts, so more practical significance, because the business models are not always good, but to compare some aspects did not have much practical significance, Furthermore This can more fully concentrate on the business use of limited resources. Identify business models, and then take the enterprise of the corresponding departments and staff with the business models for comparison, the two can be found in the performance gap, a comparative analysis to find reasons, in accordance with this business reality, the final identification of training needs. The cost of training is needed, if not through an effective way to determine whether companies need to train and the training of the way, but blind to training, such training is difficult to achieve the desired results. A comparison only difference between this model is simple and practical training.1.5 Can be part of some alternative technology, such as EDM, grinding high intensity and high hardness processingHigh-speed cutting a major feature of high-speed cutting machine has the hardness of HRC60 parts. With the use of coated carbide cutter mold processing, directly to the installation of ahardened tool steel processing forming, effectively avoid the installation of several parts of the fixture error and improve the parts of the geometric location accuracy. In the mold of traditional processing, heat treatment hardening of the workpiece required EDM, high-speed machining replace the traditional method of cutting the processing, manufacturing process possible to omit die in EDM, simplifying the processing technology and investment costs .High-speed milling in the precincts of CNC machine tools, or for processing centre, also in the installation of high-speed spindle on the general machine tools. The latter not only has the processing capacity of general machine tools, but also for high-speed milling, a decrease of investment in equipment, machine tools increased flexibility. Cutting high-speed processing can improve the efficiency, quality improvement, streamline processes, investment and machine tool investment and maintenance costs rise, but comprehensive, can significantly increase economic efficiency.2 High-speed millingHigh-speed milling the main technical high-speed cutting technology is cutting the development direction of one of it with CNC technology, microelectronic technology, new materials and new technology, such as technology development to a higher level. High-speed machine tools and high-speed tool to achieve high-speed cutting is the prerequisite and basic conditions, in high-speed machining in the performance of high-speed machine tool material of choice and there are strict requirements.2.1 High-speed milling machine in order to achieve high-speed machiningGeneral use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:General use of highly flexible high-speed CNC machine tools, machining centers, and some use a dedicated high-speed milling, drilling. At the same time a high-speed machine tool spindle system and high-speed feeding system, high stiffness of the main characteristics of high-precision targeting and high-precision interpolation functions, especially high-precision arc interpolation function. High-speed machining systems of the machine a higher demand, mainly in the following areas:High-speed milling machine must have a high-speed spindle, the spindle speed is generally 10000 ~ 100000 m / min, power greater than 15 kW. But also with rapid speed or in designated spots fast-stopping performance. The main axial space not more than 0 .0 0 0 2 m m. Often using high-speed spindle-hydrostatic bearings, air pressure-bearing, mixed ceramic bearings, magneticbearing structure of the form. Spindle cooling general use within the water or air cooled.High-speed processing machine-driven system should be able to provide 40 ~ 60 m / min of the feed rate, with good acceleration characteristics, can provide 0.4 m/s2 to 10 m/s2 acceleration and deceleration. In order to obtain good processing quality, high-speed cutting machines must have a high enough stiffness. Machine bed material used gray iron, can also add a high-damping base of concrete, to prevent cutting tool chatter affect the quality of processing. A high-speed data transfer rate, can automatically increase slowdown. Processing technology to improve the processing and cutting tool life. At present high-speed machine tool manufacturers, usually in the general machine tools on low speed, the feed of the rough and then proceed to heat treatment, the last in the high-speed machine on the half-finished and finished, in improving the accuracy and efficiency at the same time, as far as possible to reduce processing Cost.2.2 High-speed machining toolHigh-speed machining tool is the most active one of the important factors, it has a direct impact on the efficiency of processing, manufacturing costs and product processing and accuracy. Tool in high-speed processing to bear high temperature, high pressure, friction, shock and vibration, such as loading, its hardness and wear-resistance, strength and toughness, heat resistance, technology and economic performance of the basic high-speed processing performance is the key One of the factors. High-speed cutting tool technology development speed, the more applications such as diamond (PCD), cubic boron nitride (CBN), ceramic knives, carbide coating, (C) titanium nitride Carbide TIC (N) And so on. CBN has high hardness, abrasion resistance and the extremely good thermal conductivity, and iron group elements between the great inertia, in 1300 ℃ would not have happened significant role in the chemical, also has a good stability. The experiments show that with CBN cutting toolHRC35 ~ 67 hardness of hardened steel can achieve very high speed. Ceramics have good wear resistance and thermal chemical stability, its hardness, toughness below the CBN, can be used for processing hardness of HRC <5 0 parts. Carbide Tool good wear resistance, but the hardness than the low-CBN and ceramics. Coating technology used knives, cutting tools can improve hardness and cutting the rate, for cutting HRC40 ~ 50 in hardness between the workpiece. Can be used to heat-resistant alloys, titanium alloys, hightemperature alloy, cast iron, Chungang, aluminum and composite materials of high-speed cutting Cut, the most widely used. Precision machining non-ferrous metals or non-metallic materials, or the choice of polycrystalline diamond Gang-coated tool.2.3 High-speed processing technologyHigh-speed cutting technology for high-speed machining is the key. Cutting Methods misconduct, will increase wear tool to less than high-speed processing purposes. Only high-speed machine tool and not a good guide technology, high-speed machining equipment can not fullyplay its role. In high-speed machining, should be chosen with milling, when the milling cutter involvement with the workpiece chip thickness as the greatest, and then gradually decreased. High-speed machining suitable for shallow depth of cut, cutting depth of not more than 0.2 mm, to avoid the location of deviation tool to ensure that the geometric precision machining parts. Ensure that the workpiece on the cutting constant load, to get good processing quality. Cutting a single high-speed milling path-cutting mode, try not to interrupt the process and cutting tool path, reducing the involvement tool to cut the number to be relatively stable cutting process. Tool to reduce the rapid change to, in other words when the NC machine tools must cease immediately, or Jiangsu, and then implement the next step. As the machine tool acceleration restrictions, easy to cause a waste of time, and exigency stop or radical move would damage the surface accuracy. In the mold of high-speed finishing, in each Cut, cut to the workpiece, the feed should try to change the direction of a curve or arc adapter, avoid a straight line adapter to maintain the smooth process of cutting.3 Die in high-speed milling processing ofMilling as a highly efficient high-speed cutting of the new method,inMould Manufacturing has been widely used. Forging links in the regular production model, with EDM cavity to be 12 ~ 15 h, electrodes produced 2 h. Milling after the switch to high-speed, high-speed milling cutter on the hardness of HRC 6 0 hardened tool steel processing. The forging die processing only 3 h20min, improve work efficiency four to five times the processing surface roughness of Ra0.5 ~ 0.6m, fully in line with quality requirements.High-speed cutting technology is cutting technology one of the major developments, mainly used in automobile industry and die industry, particularly in the processing complex surface, the workpiece itself or knives rigid requirements of the higher processing areas, is a range of advanced processing technology The integration, high efficiency and high quality for the people respected. It not only involves high-speed processing technology, but also including high-speed processing machine tools, numerical control system, high-speed cutting tools and CAD / CAM technology. Die-processing technology has been developed in the mold of the manufacturing sector in general, and in my application and the application of the standards have yet to be improved, because of its traditional processing with unparalleled advantages, the future will continue to be an inevitable development of processing technology Direction.4 Numerical control technology and equipping development trend and countermeasureEquip the engineering level, level of determining the whole national economy of the modernized degree and modernized degree of industry, numerical control technology is it develop new developing new high-tech industry and most advanced industry to equip (such as information technology and his industry, biotechnology and his industry, aviation, spaceflight, etc. national defense industry) last technology and getting more basic most equipment. Marx has ever said "the differences of different economic times, do not lie in what is produced, and lie in how to produce,produce with some means of labor ". Manufacturing technology and equipping the most basic means of production that are that the mankind produced the activity, and numerical control technology is nowadays advanced manufacturing technology and equips the most central technology. Nowadays the manufacturing industry all around the world adopts numerical control technology extensively, in order to improve manufacturing capacity and level, improve the adaptive capacity and competitive power to the changeable market of the trends. In addition every industrially developed country in the world also classifies the technology and numerical control equipment of numerical control as the strategic materials of the country, not merely take the great measure to develop one's own numerical control technology and industry, and implement blockading and restrictive policy to our country in view of " high-grade, precision and advanced key technology of numerical control " and equipping. In a word, develop the advanced manufacturing technology taking numerical control technology as the core and already become every world developed country and accelerate economic development in a more cost-effective manner, important way to improve the overall national strength and national position. Numerical control technology is the technology controlled to mechanical movement and working course with digital information, integrated products of electromechanics that the numerical control equipment is the new technology represented by numerical control technology forms to the manufacture industry of the tradition and infiltration of the new developing manufacturing industry, namely the so-called digitization is equipped, its technological range covers a lot of fields: (1)Mechanical manufacturing technology; (2)Information processing, processing, transmission technology; (3)Automatic control technology; (4)Servo drive technology;(5)Technology of the sensor; (6)Software engineering ,etc..Development trend of a numerical control technologyThe application of numerical control technology has not only brought the revolutionary change to manufacturing industry of the tradition, make the manufacturing industry become the industrialized symbol , and with the constant development of numerical control technology and enlargement of the application, the development of some important trades (IT , automobile , light industry , medical treatment ,etc. ) to the national economy and the people's livelihood of his plays a more and more important role, because the digitization that these trades needed to equip has already been the main trend of modern development. Numerical control technology in the world at present and equipping the development trend to see, there is the following several respect [1- ] in its main research focus.5 A high-speed, high finish machining technology and new trend equippedThe efficiency, quality are subjavanufacturing technology. High-speed, high finish machining technology can raise the efficiency greatly , improve the quality and grade of the products, shorten production cycle and improve the market competitive power. Japan carries the technological research association first to classify it as one of the 5 great modern manufacturing technologies forthis, learn (CIRP) to confirm it as the centre in the 21st century and study one of the directions in international production engineering.In the field of car industry, produce one second when beat such as production of 300,000 / vehicle per year, and many variety process it is car that equip key problem that must be solved one of; In the fields of aviation and aerospace industry, spare parts of its processing are mostly the thin wall and thin muscle, rigidity is very bad, the material is aluminium or aluminium alloy, only in a situation that cut the speed and cut strength very small high, could process these muscles, walls. Adopt large-scale whole aluminium alloy method that blank " pay empty " make the wing recently, such large-scale parts as the fuselage ,etc. come to substitute a lot of parts to assemble through numerous rivet , screw and other connection way, make the intensity , rigidity and dependability of the component improved. All these, to processing and equipping the demand which has proposed high-speed, high precise and high flexibility.According to EMO2001 exhibition situation, high-speed machining center is it give speed can reach 80m/min is even high , air transport competent speed can up to 100m/min to be about to enter. A lot of automobile factories in the world at present, including Shanghai General Motors Corporation of our country, have already adopted and substituted and made the lathe up with the production line part that the high-speed machining center makes up. HyperMach lathe of U.S.A. CINCINNATI Company enters to nearly biggest 60m/min of speed, it is 100m/min to be fast, the acceleration reaches 2g, the rotational speed of the main shaft has already reached 60 000r/min. Processing a thin wall of plane parts, spend 30min only, and same part general at a high speed milling machine process and take 3h, the ordinary milling machine is being processed to need 8h; The speed and acceleration of main shaft of dual main shaft lathes of Germany DMG Company are up to 120000r/mm and 1g.In machining accuracy, the past 10 years, ordinary progression accuse of machining accuracy of lathe bring 5μm up to from 10μm already, accurate grades of machining center from 3～5μm, rise to 1～1.5μm, and ultraprecision machining accuracy is i t enter nanometer grade to begin already (0.01μm).In dependability, MTBF value of the foreign numerical control device has already reached above 6 000h, MTBF value of the servo system reaches above 30000h, demonstrate very high dependability .In order to realize high-speed, high finish machining, if the part of function related to it is electric main shaft, straight line electrical machinery get fast development, the application is expanded further .5.2 Link and process and compound to process the fast development of the lathe in 5 axesAdopt 5 axles to link the processing of the three-dimensional curved surface part, can cut with the best geometry form of the cutter , not only highly polished, but also efficiency improves by a large margin . It is generally acknowledged, the efficiency of an 5 axle gear beds can equal 2 3 axle gearbeds, is it wait for to use the cubic nitrogen boron the milling cutter of ultra hard material is milled and pared at a high speed while quenching the hard steel part, 5 axles link and process 3 constant axles to link and process and give play to higher benefit. Because such reasons as complicated that 5 axles link the numerical control system , host computer structure that but go over, it is several times higher that its price links the numerical control lathe than 3 axles , in addition the technological degree of difficulty of programming is relatively great, have restricted the development of 5 axle gear beds.At present because of electric appearance of main shaft, is it realize 5 axle complex main shaft hair structure processed to link greatly simplify to make, it makes degree of difficulty and reducing by a large margin of the cost, the price disparity of the numerical control system shrinks. So promoted 5 axle gear beds of head of complex main shaft and compound to process the development of the lathe (process the lathe including 5).At EMO2001 exhibition, new Japanese 5 of worker machine process lathe adopt complex main shaft hair, can realize the processing of 4 vertical planes and processing of the wanton angle, make 5 times process and 5 axles are processed and can be realized on the same lathe, can also realize the inclined plane and pour the processing of the hole of awls. Germany DMG Company exhibits the DMUVoution series machining center, but put and insert and put processing and 5 axles 5 times to link and process in once, can be controlled by CNC system or CAD/CAM is controlled directly or indirectly.5.3 Become the main trend of systematic development of contemporary numerical control intelligently, openly, networkedly.The numerical control equipment in the 21st century will be sure the intelligent system, the intelligent content includes all respects in the numerical control system: It is intelligent in order to pursue the efficiency of processing and process quality, control such as the self-adaptation of the processing course, the craft parameter is produced automatically; Join the convenient one in order to improve the performance of urging and use intelligently, if feedforward control , adaptive operation , electrical machinery of parameter , discern load select models , since exactly makes etc. automatically; The ones that simplified programming , simplified operating aspect are intelligent, for instance intelligent automatic programming , intelligent man-machine interface ,etc.; There are content of intelligence diagnose , intelligent monitoring , diagnosis convenient to be systematic and maintaining ,etc..Produce the existing problem for the industrialization of solving the traditional numerical control system sealing and numerical control application software. A lot of countries carry on research to the open numerical control system at present, such as NGC of U.S.A. (The Next Generation Work-Station/Machine Control), OSACA of European Community (Open System Architecture for Control within Automation Systems), OSEC (Open System Environment for Controller) of Japan, ONC (Open Numerical Control System) of China, etc.. The numerical control system melts tobecome the future way of the numerical control system open. The so-called open numerical control system is the development of the numerical control system can be on unified operation platform, face the lathe producer and end user, through changing, increasing or cutting out the structure target(numerical control function), form the serration, and can use users specially conveniently and the technical know-how is integrated in the control system, realize the open numerical control system of different variety , different grade fast, form leading brand products with distinct distinction. System structure norm of the open numerical control system at present, communication norm , disposing norm , operation platform , numerical control systematic function storehouse and numerical control systematic function software development ,etc. are the core of present research.The networked numerical control equipment is a new light spot of the fair of the internationally famous lathe in the past two years. Meeting production line , manufacture system , demand for the information integration of manufacturing company networkedly greatly of numerical control equipment, realize new manufacture mode such as quick make , fictitious enterprise , basic Entrance that the whole world make too. Some domestic and international famous numerical control lathes and systematic manufacturing companies of numerical control have all introduced relevant new concepts and protons of a machine in the past two years, if in EMO2001 exhibition, " Cyber Production Center " that the company exhibits of mountain rugged campstool gram in Japan (Mazak) (intellectual central production control unit, abbreviated as CPC); The lathe company of Japanese big Wei (Okuma ) exhibits " IT plaza " (the information technology square , is abbreviated as IT square ); Open Manufacturing Environment that the company exhibits of German Siemens (Siemens ) (open the manufacturing environment, abbreviated as OME),etc., have reflected numerical control machine tooling to the development trend of networked direction.5.4 Pay attention to the new technical standard, normal setting-up5.4.1 Design the norm of developing about the numerical control systemAs noted previously, there are better common ability, flexibility, adaptability, expanding in the open numerical control system, such countries as U.S.A. ,European Community and Japan ,etc. implement the strategic development plan one after another , carry on the research and formulation of the systematic norm (OMAC , OSACA , OSEC ) of numerical control of the open system structure, 3 biggest economies in the world have carried on the formulation that nearly the same science planned and standardized in a short time, have indicated a new arrival of period of change of numerical control technology. Our country started the research and formulation of standardizing the frame of ONC numerical control system of China too in 2000.5.4.2 About the numerical control standardThe numerical control standard is a kind of trend of information-based development of manufacturing industry. Information exchange among 50 years after numerical control technology was born was all because of ISO6983 standard, namely adopt G, M code describes how processes,。
孙明明 外文资料翻译
毕业设计(论文)外文资料翻译学院：机械电子工程学院专业：机械设计制造及其自动化姓名：孙明明学号： 070501504外文出处： The advantages of PLC control,filed under PLC Articles附件： 1.外文资料翻译译文；2.外文原文。
(用外文写)附件1：外文资料翻译译文PLC的控制优势任何控制系统从概念到进入工厂工作都要经历四个阶段。
PLC系统在每一个阶段都有优势。
第一阶段是设计，对工厂的需要进行研究和制定控制策略，传统的运行平台的设计和制造必须在设计进行前完成。
PLC系统仅仅需要的是一个模糊的关于机器的可能大小的想法和I/O数量的要求（多少输入和输出接口）。
在这个阶段输入和输出芯片十分便宜，所以可以内置一个很健全的备用容量，它允许用来补充遗漏项目和为未来的扩充做准备。
其次是设计。
传统的方案是，每一项工作都是“一次成型”这不可避免的造成了工程拖延和增加成本。
一个的PLC系统使用最简单的标准件螺栓连接在一起。
在这样的连接下开始编写 PLC程序（或者至少是写入详细的程序规范）。
下一阶段是安装，安装是一种繁琐和昂贵的工作，例如安装传感器、执行器、限制开关系统和主机的连接。
分布式PLC系统使用串行链路式的预编译，测试界面可以简化安装它带来了巨大的成本优势。
PLC的程序多数在这个阶段完成。
最后是调试，而这正是PLC真正的优势被发掘的部分。
没有任何设备在第一次就正常工作。
人性就是这样，总会有一些疏漏。
与传统的系统变动情况的耗时和昂贵相比，PLC的设计师提供了系的内置备用内存容量、备用I/O和一些备用多芯电缆线，多数的变动能迅速和相对便宜的完成。
另外一个好处是，所有的变化PLC都有记录，程序的调试和修改不会因为没有被记录而遗失，这是一个经常发生在常规系统中的问题。
还有一个额外的第五阶段，维护，一旦启动工作，并移交生产就产生了维护的问题。
所有设备都有缺点，大多数设备在错误的模式中度过了它们的大部分的时间。
机械专业毕业设计外文翻译12
Development of a high-performance laser-guided deep-holeboring tool: optimal determination of reference origin for precise guidingAbstractA laser-guided deep-hole boring tool using piezoelectric actuators was developed to prevent hole deviation. To extend the depth o controll able boring further, the following were improved. The tool’s guiding error, caused by misalignment of the corner cube prism and the mirror in the optical head from the spindle axis, was eliminated using an adjustment jig that determined the reference origins of the two position-sensitive detectors (PSDs) precisely. A single-edge counter-boring head is used instead of the double-edge head used up to now The former was thought to be better in attitude control than the latter. A new boring bar, which was lower in rigidity and better in Controllability of tool attitude, was used. Experiments were conducted to examine the performance of the new tool in detail and to determin its practical application, using duralumin (A2017-T4) workpieces with a prebored 108-mm diameter hole. The experiments were performed with a rotating tool–stationary workpiece system. Rotational speed was 270 rpm and feed was 0.125 mm/rev. Tool diameter was 110 mm Asaresult,controlled boring becomes possible up to a depth of 700 mm under the stated experimental conditions.700 mm is the maximum machinable length of the machine tool. The tool can be put to practical use.Keywords: Deep hole-boring; Adaptive control; Laser application1.IntroductionTo bore a precise straight hole, a deep-hole boring tool should be guided toward a target. From this point of view, the laser-guided deep-hole boring tool was developed [1–6]. The latest tool using piezoelectric actuators could be guided to go straight toward the target,despitedisturbances up to a depth of 388 mm [6].In the present paper, before the performance of the tool is examined, the following points are improved to extend the depth. The tool’s guiding error, caused by misalignment of the corner cube prism and the mirror in the optical head from the spindle axis, is eliminated using a jig that deter- mines the reference origins of the two position-sensitive detectors (PSDs) precisely. A single-edge counter-boring head is used instead of the double-edge head used up to now. The former is thought to be better in attitude control than the latter. A new boring bar, which is 15% lower in both bending and torsional rigidity and which is better in controllability of tool attitude, is used.2. Experimental apparatusFigs. 1 and 2 show the tool head and the experimental apparatus, respectively [6]. The head is the same as that used in experiments up to now. One cutting edge of the double-edge counter-boring head is replaced by a guide pad,And six guide pads are removed[4].By removal of the guide pads, cutting oil is supplied better between the other guide pads and hole wall. The tool head consists of an optical head, a counter-boring head, piezoelectric actuators, and an actuator holder (Fig. 1). The optical head is attached to the front surface of the counter-boring head through an adjust- ment jig. The actuator holder is connected to a rotation stopper 14 behind the tool head by two parallel plates of phosphor bronze 6 (Fig. 2). A laser source 11, and PSDs 9, 10 are set in front of the tool. The rectangular coordinates XAnd Y are set on a plane perpendicular to the spindle rotation axis(Z-axis).The optical distancebetween a dichroic mirror in the optical head and PSD 10 for measuring tool inclina- tion is 2,040 mm [2].3. Method for detection of tool position and its inclinationFig. 3 shows the method used for measuring the tool position and its inclination. The laser beam, radiated from an argon laser, reaches the dichroic mirror 6 through the beam expander 5 and the half mirror 1. The dichroic mirror separates the two beams of wavelengths 514 nm (green) and 488 nm (blue). The green beam for measuring tool position passes through the dichroic mirror 6 and reachesthe corner cube prism 8. The reflected beam passes again through 6 and is deflected by the half mirror 1 toward dichroic mirror 2. By passing through the dichroic mirror 2, it reaches the PSD 9 used for measuring tool position. The blue beam for measuring tool inclination reaches the dichroic mirror 7 with an angle of incidence equal to 0°. The dichroic mirror 7 reflects the blue beam and trans- mits parts of the green beam, which are not completelyseparated by the dichroic mirror 6. The returning beam from the dichroic mirror 7 is deflected by the mirrors 6, 1, and 2, then passing through the dichroic mirror 4, and reaches the PSD 10 for measuring tool inclination. Re- flective characteristics of dichroic mirror 4 differs from that of dichroic mirror 7.4. Acquisition of data for controlling the toolData for tool attitude control are acquired from the two PSDs for tool position and its inclination every rotation of the counter-boring head. Until now, outputs of the two PSDs (measuring tool position and its inclination) some- times did not correspond well to the measured hole devia- tion. To determine what causes this, the following is exam- ined. The tool head with the optical head is supported by two V-blocks and is aligned on the Z-axis at the same longitudinal position as in the experiment. Then, the laser beam is radiated, and the optical head is rotated manually.Fig. 4 shows variations of outputs of two PSDs with encoder pulse during one rotation of the optical head fixed on the counter-boring head. Theoretically, outputs of two PSDs are constant during one rotation of the optical head corresponding to a 1,400 pulse of output of an encoder. Changes of X- and Y-outputs of tool position are caused by change of darkness of the laser spot because of interference and polarization of the laser beam. Changes of X- and Y- outputs of tool inclination are caused by inclination of the reflecting mirror in the optical head from the Z-axis. From the last experiment [6] on, tool position and its inclination are measured at rotational pulse position 700, where the brightness of the two PSDs are preferable at the same time.5. Misalignment of the optical parts in the optical headEven if the laser source and the PSDs for tool position and its inclination are aligned on Z-axis, hole deviation appeared. To discover its cause, the misalignment of the corner cube prism and inclination of reflecting mirror in the optical head from the Z-axis are examined.Fig. 5 shows all cases of alignment errors. Fig. 5(a) shows that the corner cube prism and the reflecting mirror are precisely aligned on the Z-axis. Figs. 5(b) and 5(c) are, the cases in which the corner cube prism is displaced by and the reflecting mirror is inclined byfrom the Z-axis, respectively.IncaseofFig.5(d),errorsofFigs.5(b)and(c) occur together. Fig. 5(e) shows the case when the optical head is inclined byduring the setup of the counter-boring head. Fig. 5(f) is the worst case, when all errors occur together. These errors cannot be eliminated by conventional adjustment. Therefore a new guiding strategy is developed to ensure that the tool can be guided straight, even if errors should occur.6. Optimal setup of reference origin for precise guidingFig. 6 shows the optimal setup method of reference origins. The laser source is aligned on the Z-axis [Fig. 6(a)] [6]. The optical head is fixed to the front surface of a cylindrical alignment jig through an adjustment jig. The alignment jig is inserted into the guide bush, which is fixed on a machine table, and the centers of both alignment jig and the optical head are aligned on Z-axis. Then the laser beam is radiated. Reflected beams reach the PSDs for tool position and its inclination. When the cylinder is rotated by hand, the rotational position, at which the output is most reliable, can be found. Next, the PSDs are moved until the spots lie at their centers. This position corresponds to the pulse position 700 of the encoder. The centers are reference origins for tool position and its inclination.At this rotational position,the optical head is fixed to the counter-boring head using the adjustment jig [Fig.6(b)].When the control starts, the tool head follows the alignment jig’s axis.7. Mechanism of tool displacementFig. 7 shows the mechanism of tool displacement. Fig. 7(a) shows the normal cutting condition [7]. The cutting force P is acting on the cutting edge and is counterbalanced by the guide pads. Fig. 7(b) shows the case where the tool is to correct for a deviation. A chain double-dashed line shows the hole wall before correction of hole deviation. A Directed line shows the direction of the correction.When the tool is controlled to incline toward the direction of the directed line, a cutting edge set ahead of the guide pads overcuts the hole wall. When the guide pad on the opposite side comes to the position of the overcutting zone, the cutting edge leaves a noncutting zone on the hole wall Opposite the overcutting zone.As a result,tool shifts toward the direction of the directed line.In the case of double-edge counter-boring head, the cut- ting force acting on one cutting edge is balanced by the force that acts on the other cutting edge [7]. As a result, the head is easy to vibrate, and the mechanism of tool displace- ment does not function well.Form: Precision Engineering 24 (2000) 9–14 开发高性能的激光制导deep-holeboring工具：最佳测定参考来源精确指导摘要激光制导深孔钻具使用压电致动器是防止孔偏差。
机械专业毕业设计外文翻译10
翻译部分英文部分ADV ANCED MACHINING PROCESSESAs the hardware of an advanced technology becomes more complex, new and visionary approaches to the processing of materials into useful products come into common use. This has been the trend in machining processes in recent years.. Advanced methods of machine control as well as completely different methods of shaping materials have permitted the mechanical designer to proceed in directions that would have been totally impossible only a few years ago.Parallel development in other technologies such as electronics and computers have made available to the machine tool designer methods and processes that can permit a machine tool to far exceed the capabilities of the most experienced machinist.In this section we will look at CNC machining using chip-making cutting tools. CNC controllers are used to drive and control a great variety of machines and mechanisms, Some examples would be routers in wood working; lasers, plasma-arc, flame cutting, and waterjets for cutting of steel plate; and controlling of robots in manufacturing and assembly. This section is only an overview and cannot take the place of a programming manual for a specific machine tool. Because of the tremendous growth in numbers and capability of comp uters ,changes in machine controls are rapidly and constantly taking place. The exciting part of this evolution in machine controls is that programming becomeseasier with each new advanced in this technology.Advantages of Numerical ControlA manually operated machine tool may have the same physical characteristics as a CNC machine, such as size and horsepower. The principles of metal removal are the same. The big gain comes from the computer controlling the machining axes movements. CNC-controlled machine tools can be as simple as a 2-axis drilling machining center (Figure O-1). With a dual spindle machining center, the low RPM, high horsepower spindle gives high metal removal rates. The high RPM spindle allows the efficient use of high cutting speed tools such as diamonds and small diameter cutters (Figure O-2). The cutting tools that remove materials are standard tools such as milling cutters, drills, boring tools, or lathe tools depending on the type of machine used. Cutting speeds and feeds need to be correct as in any other machining operation. The greatest advantage in CNC machining comes from the unerring and rapid positioning movements possible. A CNC machine does dot stop at the end of a cut to plan its next move; it does not get fatigued; it is capable of uninterrupted machining error free, hour after hour. A machine tool is productive only while it is making chips.Since the chip-making process is controlled by the proper feeds and speeds, time savings can be achieved by faster rapid feed rates. Rapid feeds have increased from 60 to 200 to 400 and are now often approaching 1000 inches per minute (IPM). These high feed rates can pose a safety hazard to anyone within the working envelope of the machine tool.Complex contoured shapes were extremely difficult to product prior to CNC machining .CNC has made the machining of these shapes economically feasible. Design changes on a part are relatively easy to make by changing the program that directs the machine tool.A CNC machine produces parts with high dimensional accuracy and close tolerances without taking extra time or special precautions, CNC machines generally need less complex work-holding fixtures, which saves time by getting the parts machined sooner. Once a program is ready and production parts, each part will take exactly the same amount of time as the previous one. This repeatability allows for a very precise control of production costs. Another advantage of CNC machining is the elimination of large inventories; parts can be machined as needs .In conventional production often a great number of parts must be made at the same time to be cost effective. With CNC even one piece can be machined economically .In many instances, a CNC machine can perform in one setup the same operations that would require several conventional machines.With modern CNC machine tools a trained machinist can program and product even a single part economically .CNC machine tools are used in small and large machining facilities and range in size from tabletop models to huge machining centers. In a facility with many CNC tools, programming is usually done by CNC programmers away from the CNC tools. The machine control unit (MCU) on the machine is then used mostly for small program changes or corrections. Manufacturing with CNC tools usually requires three categories of persons. The first is the programmer, who is responsible for developing machine-ready code. The next person involved is the setup person, who loads the raw stork into the MCU, checks that the co rrect tools are loaded, and makes the first part. The third person is the machine and unloads the finished parts. In a small company, one person is expected to perform all three of these tasks.CNC controls are generally divided into two basic categories. One uses a ward address format with coded inputs such as G and M codes. The other users a conversational input; conversational input is also called user-friendly or prompted input. Later in this section examples of each of these programming formats in machining applications will be describes.CAM and CNCCAM systems have changed the job of the CNC programmer from one manually producing CNC code to one maximizing the output of CNC machines. Since CNC machine tools are made by a great number of manufacturers, many different CNC control units are in use. Control units from different manufacturers use a variety of program formats and codes. Many CNC code words are identical for different controllers, but a great number vary from one to another.To produce an identical part on CNC machine tools with different controllers such as one by FANCU, OKUMA or DYNAPATH, would require completely different CNC codes. Each manufacturer is constantly improving and updating its CNC controllers. These improvements often include additional code words plus changes in how the existing code works.A CAM systems allows the CNC programmer to concentrate on the creation of an efficient machining process, rather then relearning changed code formats. A CNC programmer looks atthe print of a part and then plans the sequence of machining operations necessary to make it (Figure O-3). This plan includes everything, from the selection of possible CNC machine tools, to which tooling to use, to how the part is held while machining takes place. The CNC programmer has to have a thorough understanding of all the capacities and limitations of the CNC machine tools that a program is to be made for. Machine specifications such as horsepower, maximum spindle speeds, workpiece weight and size limitations, and tool changer capacity are just some of the considerations that affect programming.Another area of major importance to the programmer is the knowledge of machining processes. An example would be the selection of the surface finish requirement specified in the part print. The sequence of machining processes is critical to obtain acceptable results. Cutting tool limitations have to be considered and this requires knowledge of cutting tool materials, tool types, and application recommendations.A good programmer will spend a considerable amount of time in researching the rapidly growing volume of new and improved tools and tool materials. Often the tool that was on the cutting edge of technology just two years ago is now obsolete. Information on new tools can come from catalogs or tool manufacturers' tooling engineers. Help in tool selection or optimum tool working conditions can also be obtained from tool manufacturer software. Examples would be Kennametal's "TOOLPRO", software designed to help select the best tool grade, speed, and feed rates for different work materials in turning application. Another very important feature of "TOOLPRO" is the display of the horsepower requirement for each machining selection. This allow the programmer to select a combination of cutting speed, feed rate, and depth of cut that equals the machine's maximum horsepower for roughing cuts. For a finishing cut, the smallest diameter of the part being machined is selected and then the cutting speed varied until the RPM is equal to the maximum RPM of the machine. This helps in maximizing machining efficiency. Knowing the horsepower requirement for a cut is critical if more than one tool is cutting at the same time.Software for a machining center application would be Ingersoll Tool Company's "Actual Chip Thickness", a program used to calculate the chip thickness in relation to feed-per-tooth for a milling cutter, especially during a shallow finishing cut. Ingersoll's "Rigidity Analysis" software ealculates tool deflection for end mills as a function of tool stiffness and tool force.To this point we looked at some general qualifications that a programmer should possess. Now we examine how a CAM system works. Point Control Company's SmartCam system uses the following approach. First, the programmer makes a mental model of the part to be machined. This includes the kind of machining to be performed-turning or milling. Then the part print is studied to develop a machining sequence, roughing and finishing cuts, drilling, tapping, and boring operations. What work-holding device is to be used, a vise or fixture or clamps? After these considerations, computer input can be started. First comes the creation of a JOBPLAN. This JOBPLAN consists of entries such as inch or metric units, machine type, part ID, type of workpiece material, setup notes, and a description of the required tools.This line of information describes the tool by number, type, and size and includes theappropriate cutting speed and feed rate. After all the selected tools are entered, the file is saved.The second programming step is the making of the part. This represents a graphic modeling of the projected machining operation. After selecting a tool from the prepared JOBPLAN, parameters for the cutting operation are entered. For a drill, once the coordinate location of the hole and the depth are given, a circle appears on that spot. If the location is incorrect, the UNDO command erases this entry and allows you to give new values for this operation. When an end mill is being used, cutting movements (toolpath) are usually defined as lines and arcs. As a line is programmed, the toolpath is graphically displayed and errors can be corrected instantly.At any time during programming, the command SHOWPATH will show the actual toolpath for each of the programmed tools. The tools will be displayed in the sequence in which they will be used during actual machining. If the sequence of a tool movement needs to be changed, a few keystrokes will to that.Sometimes in CAM the programming sequence is different from the actual machining order. An example would be the machining of a pocket in a part. With CAM, the finished pocket outline is programmed first, then this outline is used to define the ro ughing cuts to machine the pocket. The roughing cuts are computer generated from inputs such as depth and width of cut and how much material to leave for the finish cut. Different roughing patterns can be tried out to allow the programmer to select the most efllcient one for the actual machining cuts. Since each tool is represented by a different color, it is easy to observe the toolpath made by each one.A CAM system lets the programmer view the graphics model from varying angles, such as a top, front, side, or isometric view. A toolpath that looks correct from a top view, may show from a front view that the depth of the cutting tool is incorrect. Changes can easily be made and seen immediately.When the toolpath and the sequence of operations are satisfactory, machine ready code has to be made. This is as easy as specifying the CNC machine that is to be used to machine the part. The code generator for that specific CNC machin e during processing accesses four different files. The JOBPLAN file for the tool information and the GRAPHICE file for the toolpath and cutting sequence. It also uses the MACHINE DEFINE file which defines the CNC code words for that specific machine. This file also supplies data for maximum feed rates, RPM, toolchange times, and so on. The fourth file taking part in the code generating process is the TEMPLATE file. This file acts like a ruler that produces the CNC code with all of its parts in the right place and sequence. When the code generation is complete, a projected machining time is displayed. This time is calculated from values such as feed rates and distances traveled, noncutting movements at maximum feed rates between points, tool change times, and so on. The projected machining time can be revised by changing tooling to allow for higher metal removal rates or creating a more efficient toolpath. This display of total time required can also be used to estimate production costs. If more then one CNC machine tool is available to machine this part, making code and comparing the machining time may show that one machine is more efficient than the others.CAD/CAMAnother method of creating toolpath is with the use of a Computer-aided Drafting (CAD) file. Most machine drawings are created using computers with the description and part geometry stored in the computer database. SmartCAM, though its CAM CONNECTION, will read a CAD file and transfer its geometry represents the part profile, holes, and so on. The programmer still needs to prepare a JOBPLAN with all the necessary tools, but instead of programming a profile line by line, now only a tool has to be assigned to an existing profile. Again, using the SHOWPA TH function will display the toolpath for each tool and their sequence. Constant research and developments in CAD/CAM interaction will change how they work with each other. Some CAD and CAM programs, if loaded on the same computer, make it possible to switch between the two with a few keystrokes, designing and programming at the same time.The work area around the machine needs to be kept clean and clear of obstructions to prevent slipping or tripping. Machine surfaces should not be used as worktables. Use proper lifting methods to handle heavy workpieces, fixtures, or heavy cutting tools. Make measurements only when the spindle has come to a complete standstill. Chips should never be handled with bare hands.Before starting the machine make sure that the work-holding device and the workpiece are securely fastened. When changing cutting tools, protect the workpiece being machined from damage, and protect your hands from sharp cutting edges. Use only sharp cutting tools. Check that cutting tools are installed correctly and securely.Do not operate any machine controls unless you understand their function and what the y will do.The Early Development Of Numerically Controlled Machine ToolsThe highly sophisticated CNC machine tools of today, in the vast and diverse range found throughout the field of manufacturing processing, started from very humble beginnings in a number of the major industrialized countries. Some of the earliest research and development work in this field was completed in USA and a mention will be made of the UK's contribution to this numerical control development.A major problem occurred just after the Second World War, in that progress in all areas of military and commercial development had been so rapid that the levels of automation and accuracy required by the modern industrialized world could not be attained from the lab our intensive machines in use at that time. The question was how to overcome the disadvantages of conventional plant and current manning levels. It is generally ackonwledged that the earliest work into numerical control was the study commissioned in 1947 by the US governme nt. The study's conclusion was that the metal cutting industry throughout the entire country could not copy with the demands of the American Air Force, let alone the rest of industry! As a direct result of the survey, the US Air Force contracted the Persons Corporation to see if they could develop a flexible, dynamic, manufacturing system which would maximize productivity. TheMassachusetts Institute of Technology (MIT) was sub-contracted into this research and development by the Parsons Corporation, during the period 1949-1951,and jointly they developed the first control system which could be adapted to a wide range of machine tools. The Cincinnati Machine Tool Company converted one of their standard 28 inch "Hydro-Tel" milling machines or a three-axis automatic milling made use of a servo-mechanism for the drive system on the axes. This machine made use of a servomechanism for the drive system on the axes, which controlled the table positioning, cross-slide and spindle head. The machine cab be classified as the first truly three axis continuous path machine tool and it was able to generate a required shape, or curve, by simultaneous slide way motions, if necessary.At about the same times as these American advances in machine tool control were taking Place, Alfred Herbert Limited in the United Kingdom had their first Mutinous path control system which became available in 1956.Over the next few years in both the USA and Europe, further development work occurred. These early numerical control developments were principally for the aerospace industry, where it was necessary to cut complex geometric shapes such as airframe components and turbine blades. In parallel with this development of sophisticated control systems for aerospace requirements, a point-to-point controller was developed for more general machining applications. These less sophisticated point-to-point machines were considerably cheaper than their more complex continuous path cousins and were used when only positional accuracy was necessary. As an example of point-to-point motion on a machine tool for drilling operations, the typical movement might be fast traverse of the work piece under the drill's position-after drilling the hole, anther rapid move takes place to the next hole's position-after retraction of the drill. Of course, the rapid motion of the slideways could be achieved by each axis in a sequential and independent manner, or simultaneously. If a separate control was utilisec for each axis, the former method of table travel was less esse ntial to avoid any backlash in the system to obtain the required degree of positional accuracy and so it was necessary that the approach direction to the next point was always the same.The earliest examples of these cheaper point-to-point machines usually did not use recalculating ball screws; this meant that the motions would be sluggish, and sliderways would inevitably suffer from backlash, but more will be said about this topic later in the chapter.The early NC machines were, in the main, based upon a modified milling machine with this concept of control being utilized on turning, punching, grinding and a whole host of other machine tools later. Towards the end of the 1950s,hydrostatic slideways were often incorporated for machine tools of highly precision, which to sonic extent overcame the section problem associated with conventional slideway response, whiles averaging-out slideway inaccuracy brought about a much increased preasion in the machine tool and improved their control characteristics allows "concept of the machining center" was the product of this early work, as it allowed the machine to manufacture a range of components using a wide variety of machining processes at a single set-up, without transfer of workpieces to other variety machine tools. A machining center differed conceptually in its design from that of a milling machine, In that thecutting tools could be changed automatically by the transfer machanism, or selector, from the magazine to spindle, or vice versa.In this ductively and the automatic tool changing feature enabled the machining center to productively and efficiently machine a range of components, by replacing old tools for new, or reselecting the next cutter whilst the current machining process is in cycle.In the mid 1960s,a UK company, Molins, introduced their unique "System 24" which was meant represent the ability of a system to machine for 24 hours per day. It could be thought of as a "machining complex" which allowed a series of NC single purpose machine tools to be linked by a computerized conveyor system. This conveyor allowed the work pieces to be palletized and then directed to as machine tool as necessary. This was an early, but admirable, attempt at a form of Flexible manufacturing System concept, but was unfortunately doomed to failure. Its principal weakness was that only a small proportion of component varieties could be machine at any instant and that even fewer work pieces required the same operations to be performed on them. These factors meant that the utilization level was low, coupled to the fact that the machine tools were expensive and allowed frequent production bottlenecks of work-in-progress to arise, which further slowed down the whole operation.The early to mid-1970s was a time of revolutionary in the area of machine tool controller development, when the term computerized numerical control (CNC) became a reality. This new breed of controllers gave a company the ability to change work piece geometries, together with programs, easily with the minimum of development and lead time, allowing it to be economically viable to machine small batches, or even one-off successfully. The dream of allowing a computerized numerical controller the flexibility and ease of program editing in a production environment became a reality when two ralated factors occurred.These were:the development of integrated circuits, which reduces electronics circuit size, giving better maintenance and allowing more standardization of desing; that general purpose computers were reduced in size coupled to the fact that their cost of production had fallen considerably.The multipie benefits of cheaper electorics with greater reliability have result in the CNC fitted to the machine tools today, with the power and sophistication progtessing considerably in the last few years, allowing an almost artificial intelligence(AI) to the latest systems. Over the years, the machine tools builders have produced a large diversity in the range of applications of CNC and just some of those development will be reviewed in V olume Ⅲ。
机械工程及自动化专业外文翻译--机械工程
外文原文：Mechanical engineering1.The porfile of mechanical engineeringEngingeering is a branch of mechanical engineerig,it studies mechanical and power generation especially power and movement.2.The history of mechanical engineering18th century later periods,the steam engine invention has provided a main power fountainhead for the industrial revolution,enormously impelled each kind of mechznical biting.Thus,an important branch of a new Engineering –separated from the civil engineering tools and machines on the branch-developed together with Birmingham and the establishment of the Associantion of Mechanical Engineers in 1847 had been officially recognized.The mechanical engineering already mainly used in by trial and error method mechanic application technological development into professional engineer the scientific method of which in the research,the design and the realm of production used .From the most broad perspective,the demend continuously to enhance the efficienceyof mechanical engineers improve the quality of work,and asked him to accept the history of the high degree ofeducation and training.Machine operation to stress not only economic but also infrastructure costs to an absolute minimun.3.The field of mechanical engineeringThe commodity machinery development in the develop country,in the high level material life very great degree is decided each kind of which can realize in the mechanical engineering.Mechanical engineers unceasingly will invent the machine next life to produce the commodity,unceasingly will develop the accuracy and the complexity more and more high machine tools produces the machine.The main clues of the mechanical development is:In order to enhance the excellent in quality and reasonable in price produce to increase the precision as well as to reduce the production cost.This three requirements promoted the complex control system development.The most successful machine manufacture is its machine and the control system close fusion,whether such control system is essentially mechanical or electronic.The modernized car engin production transmission line(conveyer belt)is a series of complex productions craft mechanization very good example.The people are in the process of development in order to enable further automation of the production machinery ,the use of a computer to store and handle largevolumes of data,the data is a multifunctional machine tools necessary for the production of spare parts.One of the objectives is to fully automated production workshop,three rotation,but only one officer per day to operate.The development of production for mechanical machinery must have adequate power supply.Steam engine first provided the heat to generate power using practical methods in the old human,wind and hydropower,an increase of engin .New mechanical engineering industry is one of the challenges faced by the initial increase thermal effciency and power,which is as big steam turbine and the development of joint steam boilers basically achieved.20th century,turbine generators to provide impetus has been sustained and rapid growth,while thermal efficiency is steady growth,and large power plants per kW capital consumption is also declining.Finally,mechanical engineers have nuclear energy.This requires the application of nuclear energy particularly high reliability and security, which requires solving many new rge power plants and the nuclear power plant control systems have become highly complex electroonics,fluid,electricity,water and mechanical parts networks All in all areas related to the mechanical engineers.Small internal combustion engine,both to the type(petrol and diesel machines)or rotary-type(gas turbines and Mong Kerr machine),as well as their broad application in the field of transport should also due to mechanical enginerrs.Throughout the transport,both in the air and space,or in the terrestrial and marine,mechanial engineers created a variety of equipment and power devices to their increasing cooperation with electrical engineers,especially in the development of appropration control systems.Mechanical engineers in the development of military weapons technology and civil war ,needs a similar,though its purpose is to enhance rather than destroy their productivity.However.War needs a lot of resources to make the area of techonlogy,many have a far-reaching development in peacetime efficiency.Jet aircraft and nuclear reactors are well known examples.The Biological engineering,mechanical engineering biotechnology is a relatively new and different areas,it provides for the replacement of the machine or increase the body functions as well as for medical equipment.Artficial limbs have been developed and have such a strong movement and touch response function of the human body.In the development of artificial organ transplant is rapid,complex cardiac machines and similar equipment to enable increasingly complexsurgery,and injuries and ill patients life functions can be sustained.Some enviromental control mechanical engineers through the initial efforts to drainage or irrigation pumping to the land and to mine and ventilation to control the human environment.Modern refrigeration and air-conditioning plant commonaly used reverse heat engine,where the heat from the engine from cold places to more external heat.Many mechanical engineering products,as well as other leading technology development city have side effects on the environment,producing noise,water and air pollution caused,destroyed land and landscape.Improve productivity and diver too fast in the commodity,that the renewable natural forces keep pace.For mechanical engineers and others,environmental control is rapidly developing area,which includes a possible development and production of small quantities of pollutants machine sequnce,and the development of new equipment and teachnology has been to reduce and eliminate pollution.4.The role of mechanical engineeringThere are four generic mechanical engineers in common to the above all domains function.The 1st function is the understanding and the research mechanical sciencefoundation.It includes the power and movement of the relationship dynamics For example,in the vibration and movement of the relationship;Automatic control;Study of the various forms of heart,energy,power relations between the thermodynamic;Fluidflows; Heat transfer; Lubricant;And material properties.The 2nd function will be conducts the research,the desing and the development,this function in turn attempts to carry on the essential change to satisfy current and the future needs.This not only calls for a clear understanding of mechanical science,and have to break down into basic elements of a complex system capacity.But also the need for synthetic and innovative inventions.The 3rd function is produces the product and the power,include plan,operation and maintenance.Its goal lies in the maintenance either enhances the enterprise or the organization longer-tern and survivabilaty prestige at the same time,produces the greatest value by the least investments and the consumption.The 4th function is mechanical engineer’s coordinated function,including the management,the consultation,as well as carries on the market marking in certain situation.In all these function,one kind unceasingly to use thescience for a long time the method,but is not traditional or the intuition method tendency,this is a mechanical engineering skill aspect which unceasingly grows.These new rationalization means typical names include:The operations research,the engineering economics,the logical law problem analysis(is called PABLA) However,creativity is not rationalization.As in other areas,in mechanical engineering,to take unexpected and important way to bring about a new capacity,still has a personal,marked characteristice.5.The design of mechanical engineeringThe design of mechanical is the design has the mechanical property the thing or the system,such as:the instrument and the measuring appliance in very many situations,the machine design must use the knowledge of discipline the and so on mathematics,materials science and mechanics.Mechanical engineering desgin includeing all mechanical desgin,but it was a study,because it also includes all the branches of mechsnical engineering,such as thermodynamics all hydrodynamics in the basic disciplines needed,in the mechanical engineering design of the initial stude or mechanical design.Design stages.The entire desgin process from start to finish,in the process,a demand that is designed forit and decided to do the start.After a lot of repetition,the final meet this demand by the end of the design procees and the plan.Design considerations.Sometimes in a system is to decide which parts needs intensity parts of geometric shapesand size an important factor in this context that we must consider that the intensity is an important factor in the design.When we use expression design considerations,we design parts that may affect the entire system design features.In the circumstances specified in the design,usually for a series of such functions must be taken into account.Howeever,to correct purposes,we should recognize that,in many cases the design of important design considerations are not calculated or test can determine the components or systems.Especially students,wheen in need to make important decisions in the design and conduct of any operation that can not be the case,they are often confused.These are not special,they occur every day,imagine,for example,a medical laboratory in the mechanical design,from marketing perspective,people have high expectations from the strength and relevance of impression.Thick,and heavy parts installed together:to produce a solid impression machines.And sometimes machinery and spare parts from the design style is the point and not theother point of view.Our purpose is to make those you do not be misled to believe that every design decision will need reasonable mathematical methods.Manufacturing refers to the raw meterials into finished products in the enterprise.Create three distinct phases.They are:input,processing exprot.The first phase includes the production of all products in line with market needs essential.First there must be the demand for the product,the necessary materials,while also needs such as energy,time,human knowledge and technology resourcess .Finall,the need for funds to obtain all the other resources. Lose one stage after the second phase of the resources of the processes to be distributed.Processing of raw materials into finished products of these processes.To complete the design,based on the design,and then develop plans.Plan implemented through various production processes.Management of resources and processes to ensure efficiency and productivity.For example,we must carefully manage resources to ensure proper use of funds.Finally,people are talking about the product market was cast.Stage is the final stage of exporting finished or stage.Once finished just purchased,it must be delivered to the users.According to productperformance,installation and may have to conduct further debugging in addition,some products,especially those very complex products User training is necessary.6.The processes of materials and maunfacturingHere said engineering materials into two main categories:metals and non-ferrous,high-performance alloys and power metals.Non-metallic futher divided into plastice,synthetic rubber,composite materials and ceramics.It said the production proccess is divided into several major process,includingshape,forging,casting/ founding,heat treatment,fixed/connections ,measurement/ quality control and materal cutting.These processes can be further divide into each other’s craft.Various stages of the development of the manufacturing industry Over the years,the manufacturing process has four distinct stages of development, despite the overlap.These stages are:The first phase is artisanal,the second Phase is mechanization.The third phase is automation the forth Phase is integrated.When mankind initial processing of raw materials into finished products will be,they use manual processes.Each with their hands and what are the tools manuslly produced.This is totally integrated production take shape.A person needsindentification,collection materials,the design of a product to meet that demand,the production of such products and use it.From beginning to end,everything is focused on doing the work of the human ter in the industrial revolution introduced mechanized production process,people began to use machines to complete the work accomplished previously manual. This led to the specialization.Specialization in turn reduce the manufacture of integrated factors.In this stage of development,manufacturing workers can see their production as a whole represent a specific piece of the part of the production process.One can not say that their work is how to cope with the entire production process,or how they were loaded onto a production of parts finished.Development of manufacting processes is the next phase of the selection process automation.This is a computer-controlled machinery and processes.At this stage,automation island began to emerge in the workshop lane.Each island represents a clear production process or a group of processes.Although these automated isolated island within the island did raise the productivity of indivdual processes,but the overall productivity are often not change.This is because the island is not caught in other automated production process middle,but not synchronous withthem .The ultimate result is the efficient working fast parked through automated processes,but is part of the stagnation in wages down,causing bottlenecks.To better understand this problem,you can imagine the traffic in the peak driving a red light from the red Service Department to the next scene. Occasionally you will find a lot less cars,more than being slow-moving vehicles,but the results can be found by the next red light Brance.In short you real effect was to accelerate the speed of a red Department obstruction offset.If you and other drivers can change your speed and red light simultaneously.Will advance faster.Then,all cars will be consistent,sommth operation,the final everyone forward faster.In the workshop where the demand for stable synchronization of streamlined production,and promoted integration of manufacturing development.This is a still evolving technology.Fully integrated in the circumstances,is a computer-controllrd machinery and processing.integrated is completed through computer.For example in the preceding paragraph simulation problems,the computer will allow all road vehicles compatible with the change in red.So that everyone can steady traffic.Scientific analysis of movement,timing and mechanics of the disciplines is that it is composed of two pater:statics anddynamics.Statics analyzed static system that is in the system,the time is not taken into account,research and analysis over time and dynamics of the system change.Dynameics from the two componets.Euler in 1775 will be the first time two different branches: Rigid body movement studies can conveniently divided into two parts:geometric and mechanics.The first part is without taking into account the reasons for the downward movement study rigid body from a designated location to another point of the movement,and must use the formula to reflect the actual,the formula would determine the rigid body every point position. Therefore,this study only on the geometry and,more specifically,on the entities from excision.Obviously,the first part of the school and was part of a mechanical separation from the principles of dynamics to study movement,which is more than the two parts together into a lot easier.Dynamics of the two parts are subsequently divided into two separate disciplines,kinematic and dynamics,a study of movement and the movement strength.Therefore,the primary issue is the design of mechanical systems understand its kinematic.Kinematic studies movement,rather than a study of its impact.In a more precise kinematic studies position,displacement,rotation,speed,velocity and acceleration of disciplines,for esample,or planets orbiting research campaing is a paradigm.In the above quotation content should be pay attention that the content of the Euler dynamics into kinematic and rigid body dynamics is based on the assumption that they are based on research.In this very important basis to allow for the treatment of two separate disciplines.For soft body,soft body shape and even their own soft objects in the campaign depends on the role of power in their possession.In such cases,should also study the power and movement,and therefore to a large extent the analysis of the increased complexity.Fortunately, despite the real machine parts may be involved are more or less the design of machines,usually with heavy material designed to bend down to the lowest parts.Therefore,when the kinematic analysis of the performance of machines,it is often assumed that bend is negligible,spare parts are hard,but when the load is known,in the end analysis engine,re-engineering parts to confirm this assnmption.中文译文：机械工程1.机械工程简介机械工程是工程学的一个分支，它研究机械和动力的产，尤其是力和动力。
机械专业毕业设计外文翻译1
本科毕业设计（本科毕业论文）外文文献及译文文献、资料题目：High-rise Tower Crane designed文献、资料来源：期刊（著作、网络等）文献、资料发表（出版）日期：2000.3.25院（部）：机电工程学院专业：机电工程及自动化High-rise Tower Crane designed under Turbulent Winds At present, construction of tower cranes is an important transport operations lifting equipment, tower crane accident the people's livelihood, major hazards, and is currently a large number of tower crane drivers although there are job permits, due to the lack of means to monitor and review the actual work of a serious violation . Strengthen the inspection and assessment is very important. Tower crane tipping the cause of the accident can be divided into two aspects: on the one hand, as a result of the management of tower cranes in place, illegal operation, illegal overloading inclined cable-stayed suspended widespread phenomenon; Second, because of the tower crane safety can not be found in time For example,Took place in the tower crane foundation tilt, micro-cracks appear critical weld, bolts loosening the case of failure to make timely inspection, maintenance, resulting in the continued use of tower cranes in the process of further deterioration of the potential defect, eventually leading to the tower crane tipping. The current limit of tower crane and the black box and can not be found to connect slewing tower and high-strength bolts loosening tightened after the phenomenon is not timely, not tower verticality of the axis line of the lateral-line real-time measurement, do not have to fight the anti-rotation vehicles, lifting bodies plummeted Meng Fang, hook hoists inclined cable is a timely reminder and record of the function, the wind can not be contained in the state of suspended operation to prevent tipping on the necessary tips on site there is a general phenomenon of the overloaded overturning of the whole security risks can not be accurately given a reminder and so on, all of which the lease on the tower crane, use, management problems,Through the use of tower crane anti-tipping monitor to be resolved. Tower crane anti-tipping Monitor is a new high-tech security monitoring equipment, and its principle for the use of machine vision technology and image processing technology to achieve the measurement of the tilt tower, tower crane on the work of state or non-working state of a variety of reasons angle of the tower caused by the critical state to achieve the alarm, prompt drivers to stop illegal operation, a computer chip at the same time on the work of the state of tower crane be recorded. Tower crane at least 1 day overload condition occurs, a maximum number of days to reach 23 overloading, the driver to operate the process of playing the anti-car, stop hanging urgency, such as cable-stayed suspended oblique phenomenon often, after verification and education, to avoid the possible occurrence of fatal accidents. Wind conditions in the anti-tipping is particularly important, tower cranes sometimes connected with the pin hole and pin do not meet design requirements, to connect high-strength bolts are not loose in time after the tightening of the phenomenon, through timely maintenance in time after the tightening of the phenomenon, through timely maintenance and remedial measures to ensure that the safe and reliable construction progress. Reduced lateral line tower vertical axis measuring the number of degrees,Observation tower angle driver to go to work and organize the data once a month to ensure that the lateral body axis vertical line to meet the requirements, do not have to every time and professionals must be completed by Theodolite tower vertical axismeasuring the lateral line, simplified the management link. Data logging function to ensure that responsibility for the accident that the scientific nature to improve the management of data records for the tower crane tower crane life prediction and diagnosis of steel structures intact state data provides a basis for scientific management and proactive prevention of possible accidents, the most important thing is, if the joint use of the black box can be easily and realistically meet the current provisions of the country's related industries. Tower crane safety management at the scene of great importance occurred in the construction process should be to repair damaged steel, usually have to do a good job in the steel tower crane maintenance work and found that damage to steel structures, we must rule out potential causes of accidents, to ensure safety in production carried out smoothly. Tower crane in the building construction has become essential to the construction of mechanical equipment, tower crane at the construction site in the management of safety in production is extremely important. A long time, people in the maintenance of tower crane, only to drive attention to the conservation and electrical equipment at the expense of inspection and repair of steel structures, to bring all kinds of construction accidents.Conclusion: The tower crane anti-tipping trial monitor to eliminate potential causes of accidents to provide accurate and timely information, the tower crane to ensure the smooth development of the leasing business, the decision is correct, and should further strengthen and standardize the use of the environment (including new staff training and development of data processing system, etc.).The first construction cranes were probably invented by the Ancient Greeks and were powered by men or beasts of burden, such as donkeys. These cranes were used for the construction of tall buildings. Larger cranes were later developed, employing the use of human treadwheels, permitting the lifting of heavier weights. In the High Middle Ages, harbour cranes were introduced to load and unload ships and assist with their construction – some were built into stone towers for extra strength and stability. The earliest cranes were constructed from wood, but cast iron and steel took over with the coming of the Industrial Revolution.For many centuries, power was supplied by the physical exertion of men or animals, although hoists in watermills and windmills could be driven by the harnessed natural power. The first 'mechanical' power was provided by steam engines, the earliest steam crane being introduced in the 18th or 19th century, with many remaining in use well into the late 20th century. Modern cranes usually use internal combustion engines or electric motors and hydraulic systems to provide a much greater lifting capability than was previously possible, although manual cranes are still utilised where the provision of power would be uneconomic.Cranes exist in an enormous variety of forms – each tailored to a specific use. Sizes range from the smallest jib cranes, used inside workshops, to the tallest tower cranes,used for constructing high buildings, and the largest floating cranes, used to build oil rigs and salvage sunken ships.This article also covers lifting machines that do not strictly fit the above definition of a crane, but are generally known as cranes, such as stacker cranes and loader cranes.The crane for lifting heavy loads was invented by the Ancient Greeks in the late 6th century BC. The archaeological record shows that no later than c.515 BC distinctive cuttings for both lifting tongs and lewis irons begin to appear on stone blocks of Greek temples. Since these holes point at the use of a lifting device, and since they are to be found either above the center of gravity of the block, or in pairs equidistant from a point over the center of gravity, they are regarded by archaeologists as the positive evidence required for the existence of the crane.The introduction of the winch and pulley hoist soon lead to a widespread replacement of ramps as the main means of vertical motion. For the next two hundred years, Greek building sites witnessed a sharp drop in the weights handled, as the new lifting technique made the use of several smaller stones more practical than of fewer larger ones. In contrast to the archaic period with its tendency to ever-increasing block sizes, Greek temples of the classical age like the Parthenon invariably featured stone blocks weighing less than 15-20 tons. Also, the practice of erecting large monolithic columns was practically abandoned in favour of using several column drums.Although the exact circumstances of the shift from the ramp to the crane technology remain unclear, it has been argued that the volatile social and political conditions of Greece were more suitable to the employment of small, professional construction teams than of large bodies of unskilled labour, making the crane more preferable to the Greek polis than the more labour-intensive ramp which had been the norm in the autocratic societies of Egypt or Assyria.The first unequivocal literary evidence for the existence of the compound pulley system appears in the Mechanical Problems (Mech. 18, 853a32-853b13) attributed to Aristotle (384-322 BC), but perhaps composed at a slightly later date. Around the same time, block sizes at Greek temples began to match their archaic predecessors again, indicating that the more sophisticated compound pulley must have found its way to Greek construction sites by then.During the High Middle Ages, the treadwheel crane was reintroduced on a large scale after the technology had fallen into disuse in western Europe with the demise of the Western Roman Empire. The earliest reference to a treadwheel (magna rota) reappears in archival literature in France about 1225, followed by an illuminated depiction in a manuscript of probably also French origin dating to 1240. In navigation, the earliest uses of harbor cranes are documented for Utrecht in 1244, Antwerp in 1263, Brugge in 1288 and Hamburg in 1291, while in England the treadwheel is not recorded before 1331.Generally, vertical transport could be done more safely and inexpensively by cranes than by customary methods. Typical areas of application were harbors, mines, and, in particular, building sites where the treadwheel crane played a pivotal role in the construction of the lofty Gothic cathedrals. Nevertheless, both archival and pictorial sources of the time suggest that newly introduced machines like treadwheels or wheelbarrows did not completely replace more labor-intensive methods like ladders, hods and handbarrows. Rather, old and new machinery continued to coexist on medieval construction sites and harbors.Apart from treadwheels, medieval depictions also show cranes to be powered manually by windlasses with radiating spokes, cranks and by the 15th century also by windlasses shaped like a ship's wheel. To smooth out irregularities of impulse and get over 'dead-spots' in the lifting process flywheels are known to be in use as early as 1123.The exact process by which the treadwheel crane was reintroduced is not recorded, although its return to construction sites has undoubtedly to be viewed in close connection with the simultaneous rise of Gothic architecture. The reappearance of the treadwheel crane may have resulted from a technological development of the windlass from which the treadwheel structurally and mechanically evolved. Alternatively, the medieval treadwheel may represent a deliberate reinvention of its Roman counterpart drawn from Vitruvius' De architectura which was available in many monastic libraries. Its reintroduction may have been inspired, as well, by the observation of the labor-saving qualities of the waterwheel with which early treadwheels shared many structural similarities.In contrast to modern cranes, medieval cranes and hoists - much like their counterparts in Greece and Rome - were primarily capable of a vertical lift, and not used to move loads for a considerable distance horizontally as well. Accordingly, lifting work was organized at the workplace in a different way than today. In building construction, for example, it is assumed that the crane lifted the stone blocks either from the bottom directly into place, or from a place opposite the centre of the wall from where it could deliver the blocks for two teams working at each end of the wall. Additionally, the crane master who usually gave orders at the treadwheel workers from outside the crane was able to manipulate the movement laterally by a small rope attached to the load. Slewing cranes which allowed a rotation of the load and were thus particularly suited for dockside work appeared as early as 1340. While ashlar blocks were directly lifted by sling, lewis or devil's clamp (German Teufelskralle), other objects were placed before in containers like pallets, baskets, wooden boxes or barrels.It is noteworthy that medieval cranes rarely featured ratchets or brakes to forestall the load from running backward.[25] This curious absence is explained by the high friction force exercised by medieval treadwheels which normally prevented the wheel from accelerating beyond control.目前，塔式起重机是建筑工程进行起重运输作业的重要设备，塔机事故关系国计民生、危害重大，而目前众多的塔机司机虽然有上岗证，由于缺少监督和复核手段，实际工作中违规严重。
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本科毕业设计外文翻译装载机Loader Overview学部（学院）：专业：机械械设计制造及其自动化学生姓名：学号：指导教师：完成日期：Loader OverviewThe main function of the loader shovel of loose material and short-distance transport operations. It is the fastest growing engineering machinery, machine production and sales and market demand one. We usually see the largest wheel loaders, it is acrawler loaders. Crawler than it has good mobility, does not destroy the road surface, easy to operate, etc.. Wheel loaders has been widely used.A loader (also known as: bucket loader, front loader, front end loader, payloader, scoop loader,shovel, skip loader, and/or wheel loader) is a type of tractor, usually wheeled, sometimes on tracks, that has a front-mounted square wide bucket connected to the end of two booms (arms) to scoop up loose material from the ground, such as dirt, sand or gravel, and move it from one place to another without pushing the material across the ground. A loader is commonly used to move a stockpiled material from ground level and deposit it into an awaiting dump truck or into an open trench excavation.Loaders in general by the chassis, powertrain, running gear, working device, steeringbrake, hydraulic system and operating system.The basis of the loader classification is the Society of Automotive Engineers of America (SAE) rated capacity of the bucket. The classification is based on the largest general purpose bucket offered by the manufacturer or the bucket size adopted by the Contractor, whichever is the lesser.The loader assembly may be a removable attachment or permanently mounted. Often the bucket can be replaced with other devices or tools—for example, many can mount forks to lift heavy pallets or shipping containers, and a hydraulically opening "clamshell" bucket allows a loader to act as a light dozer or scraper. The bucket can also be augmented with devices like a bale grappler for handling large bales of hay or straw.Large loaders, such as the Kawasaki 95ZV-2, John Deere 844K, Caterpillar 950H, V olvo L120E, Case 921E, or Hitachi ZW310 usually have only a front bucket and are called Front Loaders, whereas small loader tractors are often also equipped with a small backhoe and are called backhoe loaders or loader backhoes or JCBs, after the company that first invented them.The largest loader in the world is LeTourneau L-2350. Currently these large loaders are in production in the Longview, Texas facility. The L-2350 uses a diesel electric propulsion system similar to that used in a locomotive. Each rubber tired wheel is driven by its own independent electric motor.Komatsu-integrated design offers the best value, reliability, and versatility. Hydraulics,powertrain, frame, and all other major components are engineered by Komatsu. You get a 18machine whose components are designed to work together for higher production, greater reliability, and more versatility. Komatsu’s highly productive, innovative technology, environmentally friendly machines built for the 21st century.Loaders are used mainly for uploading materials into trucks, laying pipe, clearing rubble, and digging. A loader is not the most efficient machine for digging as it cannot dig very deep below the level of its wheels, like a backhoecan. The capacity of a loader bucket can be anywhere from 0.5 to 36 m3 depending upon the size of the machine and its application. The front loader's bucket capacity is generally much bigger than a bucket capacity of a backhoe loader.Unlike most bulldozers, most loaders are wheeled and not tracked, although track loaders are common. They are successful where sharp edged materials in construction debris would damage rubber wheels, or where the ground is soft and muddy. Wheels provide better mobility and speed and do not damage paved roads as much as tracks, but provide less traction.In construction areas loaders are also used to transport building materials - such as bricks, pipe, metal bars, and digging tools - over short distances.Front loaders are commonly used to remove snow especially from sidewalks, parking lots, and other areas too small for using snowplows and other heavy equipment. They are sometimes used as snowplows with a snowplow attachment but commonly have a bucket or snowbasket, which can also be used to load snow into the rear compartment of a snowplow or dump truck.High-tip buckets are suitable for light materials such as chip, peat and light gravel and when the bucket is emptied from a height.Loaders bucket characteristics1.Bucket edge for super-hard wear resistant steel plate up to 500 Brinell hardnessfor longlife.2.Bucket shell and side Brinell hardness of 400 to resist abrasivewear. Installed bythe enhanced treatment of attachment hinge points to reduce Wear and tear.3.bucket cutting blade for resistance to abrasive wear of steel, Brinell hardness of500. Resistant liner installed in the bucket on the floor byThe bolt may be replaced, the Brinell hardness of 500.4. bolt and the edge of savings and staging to prevent unnecessary wear of thecuttingedge.5. V olvo bucket tooth system is equipped with a bolt or weld type connector, theBrinellhardness of 515, with best interpolation into the depth and the smaller the wear and tear.Skid-steer Loader Features1. The round-back bucket design is stronger with no angled corners. This configurationmakes it easier to fill and dump —improving productivity.2. The ROPS/FOPS structure protects and shields the operator.3. A total of four exterior lights help to illuminate any job site day or night.4. A safety system locks lift, tilt and drive systems when the operator leaves the seat,raises the seat bar, or turns off the ignition switch. The brakes are wet-type multiple discs that require no maintenance.5. Heavy-duty tires are standard —matching the durability of the skid-steer.6. The rugged all-welded unitized frame is constructed of .375-inch gauge steel for yearsof productivity. Step bushings are placed in all key pivot areas to increase strength and reduce stress.7. A wider wheelbase provides for a smooth ride and more balance for stability withheavier loads. A 9-inch ground clearance allows easy maneuverability through mud and other terrain.8. Hydraulic lines are protected within the loader arm.9. Mustang features a self-leveling vertical lift.10. The advanced hydraulic system affords longer service intervals and comes with a sight glass for quick and easy fluid level inspections.11. A drop-down step makes it convenient to check engine and maintenance Points.This wheel loader offers two selectable engine operating modes —Normal and Power. The operator can adjust the machine’s engine performance to match the condition requirements. This system is controlled with a dial on the right side control panel.（1）Normal Mode: provides maximum fuel efficiency for most general loading conditions.（2）Power Mode: provides maximum power output for hard digging conditions or hill climboperations.2 Automatic Transmission with Four Mode Select SystemThis operator controlled system allows the selection of manual shifting or three levels of automatic shifting modes (low, medium, and high). The operator can match the machine’s operating requirements with optimum performance efficiency. This system is controlled with a dial on the right side of the control panel.（1）Manual: The transmission is fixed to the gear speed and selected with the gear shift lever.（2）Auto Low: Low mode provides smooth gear shifting at low engine speedssuitable for general excavating and loading while offering reduced fuel consumption.（3）Auto Medium: Medium mode provides gear shifting at mid-range engine speedsrequired for more aggressive conditions.（4）Auto High: High mode provides maximum rim pull and fast cycle times byshifting the transmission at high engine speeds. This mode is suitable for hill-climb and load and carry operations..Unlike backhoes or standard tractors fitted with a front bucket, many large loaders do not use automotive steering mechanisms. Instead, they steer by a hydraulically actuated pivot point set exactly between the front and rear axles. This is referred to as "articulated steering" and allows the front axle to be solid, allowing it to carry greater weight. Articulated steering provides better maneuverability for a given wheelbase. Since the front wheels and attachment rotate on the same axis, the operator is able to "steer" his load in an arc after positioning the machine, which can be useful. The tradeoff is that when the machine is "twisted" to one side and a heavy load is lifted high, it has a greater risk of turning over to the "wide" side.Front loaders gained popularity during the last two decades, especially in urban engineering projects and small earthmoving works. Heavy equipment manufacturers offer a wide range of loader sizes and duties.The term "loader" is also used in the debris removal field to describe the boom on a grapple truck.The Israeli Combat Engineering Corps use armored Caterpillar 966 wheel loader for construction and combat engineeringmissions in hostile territories such as the West Bank. They are often seen building or removing road blocks, building bases and fortifications and starting in 2005, demolishing small houses. The IDF added armor plating for the loader, protecting it against rocks, stones, molotov cocktails, and light gunfire.Rio de Janeiro's police elite squad BOPE have recently acquired one wheel loader of military purposes to open routes and make way for the police in Rio de Janeiro's slums, which are controlled, and blocked, by drug dealers.These loaders are a popular addition to tractors from 50 to 200 hp. Its current 'drive-in' form was originally designed and developed in 1958 by a company called Quicke. They were developed to perform a multitude of farming tasks, and are popular due to their relatively low cost (compared toTelehandler) and high versatility. Tractor loaders can be fitted with many attachments such as hydraulic grabs and spikes to assist with bale and silagehandling, forks for pallet work, and buckets for more general farm activities.Popular additions to compact utility tractors and farm tractors are Front End Loaders, also referred to as a FEL. Compact utility tractors, also called CUTs are small tractors, typically with 18 to 50 horsepower (37 kW) and used primarily for grounds maintenance and landscape chores. There are 2 primary designs of compact tractor FELs, the traditional dogleg designed style and the curved arm style.John Deere Tractor manufactures a semi-curved loader design that does not feature the one piece curved arm, but also is not of the traditional two piece design. New Holland Ag introduced a compact loader with a one piece curved arm on its compact utility tractors, similar one piece curved arm loaders are now available on compact tractors on many brands including Case/Farmall, and some Montana and Kioti tractors. Kubota markets traditional loader designs on most of its compact tractors but now features a semi-curved loader design similar to the John Deere loader design on several of its small tractors.While the Front End Loaders on CUT size tractors are capable of many tasks, given their relatively small size and low capacities when compared to commercial loaders, the compact loaders can be made more useful with some simple options. A Toothbar is commonly added to the front edge of a loader bucket to aid with digging. Some loaders are equipped with a quick coupler, otherwise known as a Quick Attach (QA) system, the QA system allows the bucket to be removed easily and other tools to be added in its place. Common additions would include a set of Pallet Forks for lifting pallets of goods or a Bale Spear for lifting hay bales.A skid loader is a small loader utilizing four wheels with hydraulic drive that directs power to either, or both, sides of the vehicle. Very similar in appearance and design is the track loader, which utilizes a continuous track on either side of the vehicle instead of the wheels. Since the expiration of Bobcat's patent on its quick-connect system, newer tractor models are standardizing on that popular format for front end attachments.A swing loader is a rigid frame loader with a swinging boom. The boom can swing 180 degrees or more. Swingloaders are primarily used by the railroad industry to lay rail. Like other loaders many attachments can be attached to the boom such as magnets, forks, and buckets. Smaller swingloaders are used in farming applications for loading out. A swinging boom is advantageous where space is limited. The loader is able to lift on all sides and dump off on all sides.At present, foreign multi-functional logistics equipment and related technologies are increasingly improved, and development series, large-scale, miniaturization, multi-purpose and other direction. Internationally renowned manufacturers (such as Lynx, Case, Caterpillar, Komatsu, liebherr, V olvo, etc.) widely used in microelectronics and information technology, and improve computer-aided driving systems, information management systems, such as the application of electronic monitoring and automatic alarm system, materials used for precision fitted, upload, GPS positioning and weight of the operation of industry automatic weighing device; the use of special noise reduction materials, noise suppression to eliminate or reduce machine noise in the loader work; through continuous improvement EFI devices to further reduce exhaust emissions of diesel engines, non-polluting, economical, environmentally friendly power plant; optimize the structural design of the working device, such as a single "Z"-type linkage evolution of the eight parallel institutions, TP linkage and ERASLINK "institutions (single-action arm cast steel structure), and O & K is designedspecifically for small multi-function loader LEAR linkage in order to improve the operating productivity of the loader, have developed many of the features ultra- strong systems, such as: power electronics control / management system automatically adjusts the engine output power; engine automatic control system, when the loader in a non-working condition, automatically reduces engine speed, reducing fuel consumption and engine noise; key information display systemand so on. Loader industry leading products are basically developed in the early 1970s Liugong ZL50-based development, an international technical level of the 1960s. In the 1980's digestion and absorption of advanced technology in the United States, Caterpillar, Komatsu of Japan, and gradually the successful development of the second generation wheel loader. Compared to China's second-generation products with international advanced products in the mechanical and electrical integration, manipulation of comfort, operating efficiency, a wide gap between the biggest gap is the product reliability, domestic multi-function loader machine reliability (average time between failures is less than 400 hours), lack of core technology and key components are imported, and products a single, low-grade products. Although domestic loaders and related technical work started late, but soon the pace of development, such as multi-function loader sales have accounted for half of the loader market in the world, China has become the world's multi-function loader production and marketing power.China Loader Industry has the third-generation products. The third-generationmachine reliability is greatly improved, the main performance indicators largely withthe international advanced level. However, in reliability, comfort, operational efficiency and manufacturing levels of baking and foreign advanced level there is a considerable gap. Fourth-generation product in the third generation on the basis offurther optimization of the overall performance and configuration, the electric control box, wet brake technology has been applied, and formed a proprietary technologyand patented technologies in enterprises, so that product with a new face to the market. These will further promote the technological progress of China's loader industry.Microelectronics and information technology will be widely used, further improve thecomputer-aided driving systems, information management systems and fault diagnosis system; single sound-absorbing material, the noise suppression methodsto eliminate or reduce machine noise; through continuous improvement of the fuel injection device further reduce exhaust emissions of diesel engines. In addition tothese, but: multifunctional bucket, ripper, liquid Village hammer, snow, etc. a variety of devices, small size, power, lightweight and flexible, and better fuel economy, increased cab size and glazing area, improve the indoor air pressure to the dust, to improve the control system and the joystick position to improve the operating environment of comfort, reduce the operator's labor intensity, and beautify theappearance. Particular because of China's mining loader started late, whether it isproduct variety, performance parameters, or the use of reliability, after-sales serviceand so on, and abroad there is a considerable gap. Therefore, the trend of its development is theintroduction of foreign advanced technology to develop high-quality, multi-functional, multi-species, multi-standard range of products to increase market competitiveness; strengthen basic components, parts production and quality, in particular, is to improve the hydraulic the quality of the components, in order to achieve to meet the requirements of the premise of the product reliability,reduce product cost; improve the quality of service products.Half of the market, China has become the world's multi-function loader production and marketing power.装载机装载机是一个通常用于建筑的重型设备，主要用于将材料（等asasphalt，拆除杂物，灰尘，雪，饲料，砾石，原木，矿物原料，再生材料，岩石，沙，木屑）装入另一种类型的机械（如自卸车，输送带，进料斗，或车厢）。