国内外小型挖掘机发展综述外文文献翻译、中英文翻译、外文翻译
机械类外文文献及翻译

机械类外文文献及翻译(文档含中英文对照即英文原文和中文翻译)原文:GEAR AND SHAFT INTRODUCTIONAbstract:The important position of the wheel gear and shaft can't falter in traditional machine and modern machines.The wheel gear and shafts mainly install the direction that delivers the dint at the principal axis box. The passing to process to make them can is divided into many model numbers, using for many situations respectively. So we must be the multilayers to the understanding of the wheel gear and shaft in many ways .Key words: Wheel gear; ShaftIn the force analysis of spur gears, the forces are assumed to act in a single plane. We shall study gears in which the forces have three dimensions. The reason for this, in the case of helical gears, is that the teeth are not parallel to the axis of rotation. And in the case ofbevel gears, the rotational axes are not parallel to each other. There are also other reasons, as we shall learn.Helical gears are used to transmit motion between parallel shafts. The helix angle is the same on each gear, but one gear must have a right-hand helix and the other a left-hand helix. The shape of the tooth is an involute helicoid. If a piece of paper cut in the shape of a parallelogram is wrapped around a cylinder, the angular edge of the paper becomes a helix. If we unwind this paper, each point on the angular edge generates an involute curve. The surface obtained when every point on the edge generates an involute is called an involute helicoid.The initial contact of spur-gear teeth is a line extending all the way across the face of the tooth. The initial contact of helical gear teeth is a point, which changes into a line as the teeth come into more engagement. In spur gears the line of contact is parallel to the axis of the rotation; in helical gears, the line is diagonal across the face of the tooth. It is this gradual of the teeth and the smooth transfer of load from one tooth to another, which give helical gears the ability to transmit heavy loads at high speeds. Helical gears subject the shaft bearings to both radial and thrust loads. When the thrust loads become high or are objectionable for other reasons, it may be desirable to use double helical gears. A double helical gear (herringbone) is equivalent to two helical gears of opposite hand, mounted side by side on the same shaft. They develop opposite thrust reactions and thus cancel out the thrust load. When two or more single helical gears are mounted on the same shaft, the hand of the gears should be selected so as to produce the minimum thrust load.Crossed-helical, or spiral, gears are those in which the shaft centerlines are neither parallel nor intersecting. The teeth of crossed-helical fears have point contact with each other, which changes to line contact as the gears wear in. For this reason they will carry out very small loads and are mainly for instrumental applications, and are definitely not recommended for use in the transmission of power. There is on difference between a crossed heli : cal gear and a helical gear until they are mounted in mesh with each other. They are manufactured in the same way. A pair of meshed crossed helical gears usually have the same hand; that is ,a right-hand driver goes with a right-hand driven. In the design of crossed-helical gears, the minimum sliding velocity is obtained when the helix angle areequal. However, when the helix angle are not equal, the gear with the larger helix angle should be used as the driver if both gears have the same hand.Worm gears are similar to crossed helical gears. The pinion or worm has a small number of teeth, usually one to four, and since they completely wrap around the pitch cylinder they are called threads. Its mating gear is called a worm gear, which is not a true helical gear. A worm and worm gear are used to provide a high angular-velocity reduction between nonintersecting shafts which are usually at right angle. The worm gear is not a helical gear because its face is made concave to fit the curvature of the worm in order to provide line contact instead of point contact. However, a disadvantage of worm gearing is the high sliding velocities across the teeth, the same as with crossed helical gears.Worm gearing are either single or double enveloping. A single-enveloping gearing is onein which the gear wraps around or partially encloses the worm.. A gearing in which each element partially encloses the other is, of course, a double-enveloping worm gearing. The important difference between the two is that area contact exists between the teeth of double-enveloping gears while only line contact between those of single-enveloping gears. The worm and worm gear of a set have the same hand of helix as for crossed helical gears, but the helix angles are usually quite different. The helix angle on the worm is generally quite large, and that on the gear very small. Because of this, it is usual to specify the lead angle on the worm, which is the complement of the worm helix angle, and the helix angle on the gear; the two angles are equal for a 0-deg. Shaft angle.When gears are to be used to transmit motion between intersecting shaft, some of bevel gear is required. Although bevel gear are usually made for a shaft angle of 0 deg. They may be produced for almost any shaft angle. The teeth may be cast, milled, or generated. Only the generated teeth may be classed as accurate. In a typical bevel gear mounting, one of the gear is often mounted outboard of the bearing. This means that shaft deflection can be more pronounced and have a greater effect on the contact of teeth. Another difficulty, which occurs in predicting the stress in bevel-gear teeth, is the fact the teeth are tapered.Straight bevel gears are easy to design and simple to manufacture and give very good results in service if they are mounted accurately and positively. As in the case of squr gears, however, they become noisy at higher values of the pitch-line velocity. In these cases it is often go : od design practice to go to the spiral bevel gear, which is the bevel counterpart of thehelical gear. As in the case of helical gears, spiral bevel gears give a much smoother tooth action than straight bevel gears, and hence are useful where high speed are encountered.It is frequently desirable, as in the case of automotive differential applications, to have gearing similar to bevel gears but with the shaft offset. Such gears are called hypoid gears because their pitch surfaces are hyperboloids of revolution. The tooth action between such gears is a combination of rolling and sliding along a straight line and has much in common with that of worm gears.A shaft is a rotating or stationary member, usually of circular cross section, having mounted upon it such elementsas gears, pulleys, flywheels, cranks, sprockets, and other power-transmission elements. Shaft may be subjected to bending, tension, compression, or torsional loads, acting singly or in combination with one another. When they are combined, one may expect to find both static and fatigue strength to be important design considerations, since a single shaft may be subjected to static stresses, completely reversed, and repeated stresses, all acting at the same time.The word “shaft” covers numerous v ariations, such as axles and spindles. Anaxle is a shaft, wither stationary or rotating, nor subjected to torsion load. A shirt rotating shaft is often called a spindle.When either the lateral or the torsional deflection of a shaft must be held to close limits, the shaft must be sized on the basis of deflection before analyzing the stresses. The reason for this is that, if the shaft is made stiff enough so that the deflection is not too large, it is probable that the resulting stresses will be safe. But by no means should the designer assume that they are safe; it is almost always necessary to calculate them so that he knows they are within acceptable limits. Whenever possible, the power-transmission elements, such as gears or pullets, should be located close to the supporting bearings, This reduces the bending moment, and hence the deflection and bending stress.Although the von Mises-Hencky-Goodman method is difficult to use in design of shaft, it probably comes closest to predicting actual failure. Thus it is a good way of checking a shaft that has already been designed or of discovering why a particular shaft has failed in service. Furthermore, there are a considerable number of shaft-design problems in which the dimension are pretty well limited by other considerations, such as rigidity, and it is only necessary for the designer to discover something about the fillet sizes, heat-treatment,and surface finish and whether or not shot peening is necessary in order to achieve the required life and reliability.Because of the similarity of their functions, clutches and brakes are treated together. In a simplified dynamic representation of a friction clutch, or brake, two in : ertias I and I traveling at the respective angular velocities W and W, one of which may be zero in the case of brake, are to be brought to the same speed by engaging the clutch or brake. Slippage occurs because the two elements are running at different speeds and energy is dissipated during actuation, resulting in a temperature rise. In analyzing the performance of these devices we shall be interested in the actuating force, the torque transmitted, the energy loss and the temperature rise. The torque transmitted is related to the actuating force, the coefficient of friction, and the geometry of the clutch or brake. This is problem in static, which will have to be studied separately for eath geometric configuration. However, temperature rise is related to energy loss and can be studied without regard to the type of brake or clutch because the geometry of interest is the heat-dissipating surfaces. The various types of clutches and brakes may be classified as fllows:. Rim type with internally expanding shoes. Rim type with externally contracting shoes. Band type. Disk or axial type. Cone type. Miscellaneous typeThe analysis of all type of friction clutches and brakes use the same general procedure. The following step are necessary:. Assume or determine the distribution of pressure on the frictional surfaces.. Find a relation between the maximum pressure and the pressure at any point. Apply the condition of statical equilibrium to find (a) the actuating force, (b) the torque, and (c) the support reactions.Miscellaneous clutches include several types, such as the positive-contact clutches, overload-release clutches, overrunning clutches, magnetic fluid clutches, and others.A positive-contact clutch consists of a shift lever and two jaws. The greatest differences between the various types of positive clutches are concerned with the design of the jaws. To provide a longer period of time for shift action during engagement, the jaws may be ratchet-shaped, or gear-tooth-shaped. Sometimes a great many teeth or jaws are used, and they may be cut either circumferentially, so that they engage by cylindrical mating, or on the faces of the mating elements.Although positive clutches are not used to the extent of the frictional-contact type, they do have important applications where synchronous operation is required.Devices such as linear drives or motor-operated screw drivers must run to definite limit and then come to a stop. An overload-release type of clutch is required for these applications. These clutches are usually spring-loaded so as to release at a predetermined toque. The clicking sound which is heard when the overload point is reached is considered to be a desirable signal.An overrunning clutch or coupling permits the driven member of a machine to “freewheel” or “overrun” bec ause the driver is stopped or because another source of power increase the speed of the driven. This : type of clutch usually uses rollers or balls mounted between an outer sleeve and an inner member having flats machined around the periphery. Driving action is obtained by wedging the rollers between the sleeve and the flats. The clutch is therefore equivalent to a pawl and ratchet with an infinite number of teeth.Magnetic fluid clutch or brake is a relatively new development which has two parallel magnetic plates. Between these plates is a lubricated magnetic powder mixture. An electromagnetic coil is inserted somewhere in the magnetic circuit. By varying the excitation to this coil, the shearing strength of the magnetic fluid mixture may be accurately controlled. Thus any condition from a full slip to a frozen lockup may be obtained.齿轮和轴的介绍摘要:在传统机械和现代机械中齿轮和轴的重要地位是不可动摇的。
挖掘机外文翻译外文文献中英翻译

挖掘机外文翻译外文文献中英翻译Excavator Translation: English Translation of Foreign LiteratureAbstract:The translation of foreign literature plays a significant role in acquiring knowledge and broadening horizons. In this article, we will explore the translation of foreign literature related to excavators. By analyzing various examples, we aim to provide an insightful understanding of the translation process and techniques involved in conveying the essence of foreign texts to the target language.1. IntroductionThe field of construction machinery presents numerous challenges when it comes to translation due to the technical nature of the content. Translating related literature helps engineers and professionals gain access to international best practices, safety guidelines, and advancements. One of the key areas within construction machinery is excavators, which serve as the focus of this article's English translation of foreign literature.2. Historical Background and EvolutionBefore delving into translations of foreign literature, it is essential to understand the historical background and evolution of excavators. The first excavators can be traced back to ancient civilizations such as the Egyptians and Greeks. Through detailed research and analysis, these ancient excavation methods have gradually evolved into the sophisticated machinery used today.3. Translation Techniques for Excavator-Related TerminologyTranslating technical terms accurately is crucial in preserving the integrity and clarity of the original text. When it comes to excavators, some terms might not have a direct equivalent in the target language. In such cases, the translator must employ various techniques like borrowing, calque, explanation, or using a closest possible translation. Balancing accuracy and readability is a crucial aspect of this translation process.4. Examples of Translated Excavator LiteratureTo demonstrate the translation techniques mentioned earlier, several examples will be provided in this section. These examples will range from user manuals, safety guidelines, to technical specifications and advancements. Through examining these examples, readers will gain insight into the specific challenges faced during translation and the strategies usedto overcome them.5. Cultural Considerations in Excavator TranslationsIn addition to technical accuracy, cultural considerations play a vital role in translating excavator literature. Different cultures may have varying perceptions and terminologies related to construction machinery. Translators need to be aware of cultural nuances to ensure that the translated materials are not only accurate but also culturally appropriate for the target audience.6. ConclusionIn conclusion, the translation of foreign literature on excavators is of great importance in the field of construction machinery. By accurately conveying the technical details, safety guidelines, and advancements fromforeign texts, engineers and professionals can broaden their knowledge and stay updated with international practices. The translation process involves employing various techniques and considering cultural aspects. As a result, it is crucial for translators to possess both technical expertise and cultural sensitivity when undertaking such translations.Through this article, we have explored the significance of excavator translation, the challenges faced, and the techniques employed. It is the bridge that connects language barriers, facilitates learning, and fosters advancements in the field.。
掘进机在采矿和隧道中的应用外文文献翻译、中英文翻译

外文资料Application of tunneling machine in mining and tunnelBoring machine for convenient mining hard rock and provides a unique capability. Therefore, widely is applied in underground, mining and tunneling. In the successful use of the tunnelling machine a a decisive issue is improve machine productivity and reduce the mining cost of reliability analysis. This article presents and discusses the Colorado School of geomechanics research recently completed work for mining in the history of the use of data as a dynamic performance model. This model is from different roadheader under various geological conditions of work based to an extensive collection of data. This article also discussed the development and content of the database The prediction of cutting rate and energy consumption of the boring machine is the program.At present, the mechanical mining system broad use in mining and civil construction, and the main trend is to improve productivity and reduce the cost, the main benefit is to reduce land possession of; at the same time, enhance the safety of workers. These are mainly depending on machine performance of a substantial increase in, the reliability has caused the expansion of mining market and the level of workers has been improved.Boring machine is a kind of widely used in underground soft rock tunneling machine, especially for those sedimentary rocks. They used in the production and development of soft rock mining industry, especially used in coal mines, mines. In the municipal construction, often used in soft ground pipeline digging. And TBM application ability is widely can be basically any structure and section size of mining, regardless of roadway section has more complex can satisfy people's needs. Therefore, people have unanimously welcomed.In addition to the high flexibility and adaptability, boring machine also amaximum cost is low, good economy, general of roadheader have great power, but it is controlled by electromagnetic convenient. Therefore, compared with other machine, it can better dig into hard rock and crushed, such as continuous mining and mining.Today, in the science and technology rapid development, people design the roadheader performance and other aspects have made great progress, they have far more than the coal mining, the main change in recent 50 years. The machine weight and size than the previous increase a lot, cutting head power increased, the supporting rod, rake mechanism and control system have been greatly improved. High efficiency cutting head design, high cutting rate cut tooth development, high pressure water jet assisted cutting, electric hydraulic integration, the larger the place was the use of automatic control system and According to the different geological conditions of indirect control, so these all make the cutting capacity of the machine, work efficiency, power and so on have been greatly improved.中文译文掘进机在采矿和隧道中的应用掘进机为方便的挖掘硬岩而提供了一个独特的能力。
农业用机械设备外文文献翻译、中英文翻译、外文翻译

农业用机械设备外文文献翻译、中英文翻译、外文翻译在公元前1世纪,中国已经开始推广使用耧,这是世界上最早的条播机具,在北方旱作区仍然得到应用。
1636年,希腊制造了世界上第一台播种机。
1830年,俄国人在畜力多铧犁上加装播种装置制成了犁播机。
1860年后,英美等国开始大量生产畜力谷物条播机。
20世纪后,牵引和悬挂式谷物条播机以及运用气力排种的播种机相继出现。
50年代,精密播种机开始得到发展。
中国从20世纪50年代开始引进谷物条播机、棉花播种机等。
60年代,中国先后研制成了悬挂式谷物播种机、离心式播种机、通用机架播种机和气吸式播种机等多种类型,并研制成了磨纹式排种器。
到70年代,中国已经形成了播种中耕通用机和谷物联合播种机两个系列,并成功研制出了精密播种机。
播种机具有播种均匀、深浅一致、行距稳定、覆土良好、节省种子、工作效率高等特点。
正确使用播种机应注意以下10个要点:1)在进田作业前,要清理播种箱内的杂物和开沟器上的缠草、泥土,确保状态良好。
对拖拉机及播种机的各传动、转动部位,按照说明书的要求加注润滑油,尤其是每次作业前要注意传动链条润滑和张紧情况以及播种机上螺栓的紧固情况。
2)机架不能倾斜,播种机与拖拉机挂接后,不得倾斜,工作时应使机架前后呈水平状态。
3)搞好各种调整,按照使用说明书的规定和农艺要求,将播种量、开沟器的行距、开沟覆土镇压轮的深浅调整适当。
Seeder Tips1.Pay n to adding good quality seeds to the seed box to XXX。
Make sure there are no small。
broken。
or impure seeds。
Also。
XXX.2.Before large-scale seeding。
conduct a 20-XXX.3.Choose a suitable route for the seeding machine to move ina straight line at a constant speed。
毕业论文外文资料翻译-现代起重机的特征和发展趋向

Characteristics and DevelopmentalTendency of Modern CranesWith rapid development of modern science and technology, magnification of industrial production scale and improvement of automation level, application of cranes is becoming widespread and its function is obvious. Meanwhile, requirements for cranes are more and more strict. Especially, the widespread use of electronic computer technology spurs lots of subject-crossing advanced design approaches and accelerates the improvement of modern manufacturing and detecting technology. Fierce competition in international market becomes more dependent on the competition of technology. All of these impel technological functions of cranes into a brand-new developmental stage. Cranes are facing a tremendous transformation.Our country is entering global international competitive market at an unprecedented rate and crane manufacture is confronted with a new situation where opportunities and challenges coexist. Thus, it is crucial for cranes to develop and innovate constantly. I want to make a brief explanation about characteristics and developmental tendency of modern cranes with examples, based on new theories, technology and trend of cranes at home and overseas.1.Make the key products large, high speed, endured and specializedBecause of continuous expansion of industrial production scale, increasingly improvement of production efficiency and rising proportion of money spending on loading and unloading and transporting materials in the process of production, required amount of large or high-speed cranes is increasing. Lifting quantities become larger, working speed becomes higher and requirements of energy-consuming and reliability become stricter. Cranes have already become a critical link in the process of automation production. Cranes should be easy to use, maintain and operate and have high security, less troubles and long average time between failures. The central issue in international market production competition is reliability, and many companies abroad have drawn up inter-controlled standard of reliability. The most important for us to catch up with and surpass world advanced level of crane’s function is to improve reliability, to make cranes durable, less troubles, maintainable and economic to be used.At the moment, the biggest floating crane in the world weighs 6500t, chain crane 3000t and bridge crane 1200t.Diversity of industrial mode of production and customers’need makes crane market expanding and products renewing constantly to satisfy special needs with specific functions and bring its best usefulness into play. Functions of various kinds of cranes are improving. DEMAG ERGOTECH has developed a crane special for aircraft maintenance, which has made its own way into international market. This crane is great in length and lifting height and has accurate halt. When a flexible maintenance platform fixed under lifting cart, it can reach every part of the aircraft. With the fast development of nuclear power stations in the world, cranes which are special for them achieve corresponding development. For example, annular bridge crane in reactors’space, working under radiative circumstances, is used to lift dangerous load such as top cover of pressure container and components in reactors. It requires high reliability, high security, the ability to determine location accurately and automatically and transfer goods to a lower level, as well as various kinds of protection and particular security devices.2. Make series of production modularized, combined, standardized and practicalMost cranes are produced by series and batch, thus use of systematic multi-objections entire optimization to design series of cranes has already become the key point in development. Through rational matching of series main parameter, its functions can be improved, manufacturing cost can be reduced, and degree of general purpose can be raised. Use less specification spare parts to compose series production with multi-species and multi-specifications. And thus, the requirements of customers can be fully satisfied.By using modularized design instead of conservative entire design, we can make components with similar functions into standard modules which have various uses, similar connective key factors and are interchangeable. Through combination of different modules, we can make different kinds and specifications of cranes. There are only several modules involved when it comes to crane improvement. To design a new style of crane, all that you do is to choose different modules to recompose. Because of improvement in degree of general purpose, single products with small serial production can transform into module production of pretty great batches. As a result, we can achieve specialization production with high efficiency and cut manufacturing cost. It can satisfy marketing demands and increase competitive capacity by composing cranes of various series and specifications using less modularized forms.Bridge crane produced by DEMAG ERGOTECH considered carefully modularization and combination. It makes inter-parameter of series, entirety, mechanism and components matched with each other. The distribution of capacity obtains most economic and suitable effects. To make the main components of lifting mechanism reaches its largest general purpose, the method that the result of lifting weights multiplying lifting speed is a constant has been used. There are more specifications derived through changes of pulley multiplying power. Series of 5-125t bridge cranes only need four basic lifting carts even with various working ranks. Module series of standard wheel cases, which are produced by the company, have various groups of linking holes which can choose different drive unit to form platform carts. They can also combine with metal construction components to be used as running machine of various kinds of cranes; its wheels have several forms of surfaces to be chosen. Because of no basic distance limit and flexible combination, they are widely used. The company’s series of end bridge standard modules have commercialized. It resorts to frictional cycle and high intensity bolt link which improves interchange and accuracy of sizes and reduces machining of connecting covers. It can connect to each main beam quickly and effectively. There are two kinds of end beam modules; one is suitable for single beam and the other is for double beams. According to length and weights, end beam style can be decided.3. Make productions for general purposes small, light, simple and diversifiedThere are quite a number of cranes used in general workshop and storehouse, and thus they have light work and the requirement is not very strict. How to improve application of these cranes and to cut manufacturing cost is critical to win in the marketing competition. Considering comprehensive benefit, the need to decrease the height of cranes as low as possible, to simplify the constructions and to reduce weights and wheel pressure can also decrease structure’s height, lighten structure composition and reduce cost of producing and maintenance. So there will be fast development of electric calabash bridge and light beam cranes, and bridge cranes for general purposes will be replaced by them.The needs of customers advance diversity of cranes. Series parameter scale of cranes expanding and functions enlarging, product of one machine for several useswill obtain further development to increase capacity of dealing with emergencies. The proportion of using wireless remote control under normal conditions will increase.DEMAG ERGOTECH has formed standard crane series of light combinations after long period explosion and innovation. The whole series compose of various productions such as combination “工” style single beam, hanging case single beam, horn cart case single beam and case double beams. There are altogether fifteen forms of connection between main beam and end beam. This is suitable for needs of different structure and lifting goods. Each specification of crane has three single speeds and three double speeds to be chosen. There are seven operating ways. In addition, different electric conduction pattern and different electric control pattern can match hundreds and thousands of cranes through different combinations to fully satisfy different needs of customers. Another advantage of the crane is that they are light. Compared to productions at home, its lifting weight is 32t and length 25.5m compared to 46.4t------weight of double beams cranes in our country, 28.3t------ electric calabash bridge cranes. Weight of DEMAG electric calabash bridge crane is only 18.5, which is lighter than domestic productions by 60 percent and 35percent respectively.现代起重机的特征和发展趋向随着现代科学技术的迅速发展,工业生产规模的扩大和自动化程度的提高,起重机在现代化生产过程中应用越来越广,作用愈来愈大,对起重机的要求也越来越高。
现代工程机械行业的技术进步外文文献翻译、中英文翻译、外文翻译

附录现代工程机械行业的技术进步大型机械式挖掘机在目前国际国内在矿山开采及工程施工中有着广泛的应用,其性能的优劣对生产率有很大的影响.在国际市场竟争日趋激烈的今天,如何提高产品的质量是提高其市场竞争力的关键。
目前,我国的大型机械式挖掘机在设计水平,设计手段及产品质量上与国外同类产品相比尚有较大差距.国外已经将人一机一环境作为一个系统统一考虑,提倡低振动、低噪音的绿色设计,将现代设计方法(电子模拟理论、动态设计、可靠性设计等)普遍地应用于挖掘机设计,使产品设计现代化,性能可靠。
而我国仍然主要采用传统的仿型设计,而近年来才将现代设计方法逐步应用到挖掘机的设计上,但在这方面工作开展的不得力,主要表现在自行设计开发能力不够,基础工作做得不完善,尤其在挖掘机动力学方面。
挖掘机结构非常复杂,往往是多发动机同时驱动,同时工作环境恶劣,外载荷成随机性变化,因此在设计大型矿用挖掘机的新产品时,为了使其作业安全,工作顺畅,除必要的理论分析和静强度计算外,还必须要进行动力学分析和计算,以在设计之初保证机械的动强度和可靠性。
在进行这种分析时,土壤的力学特性必须考虑,而且是重要因素。
通过进行动力学研究,才能确定挖掘机各部件的载荷特性,设计出质量可靠的产品。
Modern construction machinery industry of technical progress Large-size mechanical mining excavator is used widely in international and domestic engineering construction and mining performance, and its property defines the efficiency much.Now because the international market is opened step step, how to promote the quality of excavator is the key that a factory reinforces its competing force.In our country,the designing elevation and production quality on excavator can not keep up with international advanced technology applying on excavator.Now the advanced technology has already applied advanced designing method on excavator designing,such as electronic simulating theory,dynamic design, reliability design and so on.But in our country ,the most excavator design has still applied the traditional design method ,the modern design method has not began to be actually applied .The prime display is that the capability of self-design is not enough and the basic work has not done perfectly especially the excavator kinetics .The construct of excavator is very complex and the multiple movers often work simultaneously.at the same time its working environment is very bad and the eternal load varies randomly.As a result ,when designing the new product of excavator ,in order to ensure the performance safety,the designer not only has the basic theory analysis on static load computing ,but also do necessary work about the kinetics of mechanism to qualify the dynamic reliability in the period of designing .Trough the kinetic analysis ,the load property of all the elements in excavator can be decided so as to design reliable product .。
掘进机论文中英文对照资料外文翻译文献

中英文对照资料外文翻译文献英文文献Roadheader applications in mining and tunneling industries ABSTRACTRoadheaders offer a unique capability and flexibility for the excavation of soft to medium strength rock formations, therefore, are widely used in underground mining and tunneling operations. A critical issue in successful roadheader application is the ability to develop accurate and reliable estimates of machine production capacity and the associated bit costs. This paper presents and discusses the recent work completed at the Earth Mechanics Institute of Colorado School of Mines on the use of historical data for use as a performance predictor model. The model is based on extensive field data collected from different roadheader operations in a wide variety of geologic formations. The paper also discusses the development of this database and the resultant empirical performance prediction equations derived to estimate roadheader cutting rates and bit consumption.INTRODUCTIONThe more widespread use of the mechanical excavation systems is a trend set by increasing pressure on the mining and civil construction industries to move away from the conventional drill and blast methods to improve productivity and reduce costs. The additional benefits of mechanical mining include significantly improved safety, reduced ground support requirements and fewer personnel. These advantages coupled with recent enhancements in machine performance and reliability have resulted in mechanical miners taking a larger share of the rock excavation market.Roadheaders are the most widely used underground partial-face excavation machines for soft to medium strength rocks, particularly for sedimentary rocks. They are used for both development and production in soft rock mining industry (i.e. main haulage drifts, roadways, cross-cuts, etc.) particularly in coal, industrial minerals and evaporitic rocks. In civil construction, they findextensive use for excavation of tunnels (railway, roadway, sewer, diversion tunnels, etc.) in soft ground conditions, as well as for enlargement and rehabilitation of various underground structures. Their ability to excavate almost any profile opening also makes them very attractive to those mining and civil construction projects where various opening sizes and profiles need to be constructed.In addition to their high mobility and versatility, roadheaders are generally low capital cost systems compared to the most other mechanical excavators. Because of higher cutting power density due to a smaller cutting drum, they offer the capability to excavate rocks harder and more abrasive than their counterparts, such as the continuous miners and the borers. ROADHEADERS IN LAST 50 YEARSRoadheaders were first developed for mechanical excavation of coal in the early 50s. Today, their application areas have expanded beyond coal mining as a result of continual performance increases brought about by new technological developments and design improvements. The major improvements achieved in the last 50 years consist of steadily increased machine weight, size and cutterhead power, improved design of boom, muck pick up and loading system, more efficient cutterhead design, metallurgical developments in cutting bits, advances in hydraulic and electrical systems, and more widespread use of automation and remote control features. All these have led to drastic enhancements in machine cutting capabilities, system availability and the service life.Machine weights have reached up to 120 tons providing more stable and stiffer (less vibration, less maintenance) platforms from which higher thrust forces can be generated for attacking harder rock formations. . The cutterhead power has increased significantly, approaching 500 kW to allow for higher torque capacities. Modern machines have the ability to cutcross-sections over 100m2 from a stationary point. Computer aided cutterhead lacing design has developed to a stage to enable the design of optimal bit layout to achieve the maximum efficiency in the rock and geologic conditions to be encountered. The cutting bits have evolved from simple chisel to robust conical bits. The muck collection and transport systems have also undergone major improvements, increasing attainable production rates. The loading apron can now be manufactured as an extendible piece providing for more mobility and flexibility. The machines can be equipped with rock bolting and automatic dust suppression equipment to enhance the safetyof personnel working at the heading. They can also be fitted with laser-guided alignment control systems, computer profile controlling and remote control systems allowing for reduced operator sensitivity coupled with increased efficiency and productivity. Figure-1 shows a picture of a modern transverse type roadheader with telescopic boom and bolting system.Mobility, flexibility and the selective mining capability constitute some of the most important application advantages of roadheaders leading to cost effective operations. Mobility means easy relocation from one face to another to meet the daily development and production requirements of a mine. Flexibility allows for quick changes in operational conditions such asFigure-1: A Transverse Cutterhead Roadheader (Courtesy of Voest Alpine)different opening profiles (horse-shoe, rectangular, etc.), cross-sectional sizes, gradients (up to 20, sometimes 30 degrees), and the turning radius (can make an almost 90 degree turn). Selectivity refers to the ability to excavate different parts of a mixed face where the ore can be mined separately to reduce dilution and to minimize waste handling, both contributing to improved productivity. Since roadheaders are partial-face machines, the face is accessible, and therefore, cutters can be inspected and changed easily, and the roof support can be installed very close to the face. In addition to these, high production rates in favorable ground conditions, improved safety, reduced ground support and ventilation requirements, all resulting in reduced excavation costs are the other important advantages of roadheaders.The hard rock cutting ability of roadheaders is the most important limiting factor affecting their applications. This is mostly due to the high wear experienced by drag bits in hard, abrasiverocks. The present day, heavy-duty roadheaders can economically cut most rock formations up to 100 MPa (~14,500 psi) uniaxial compressive strength (UCS) and rocks up to 160 MPa (~23,000 psi) UCS if favorable jointing or bedding is present with low RQD numbers. Increasing frequency of joints or other rock weaknesses make the rock excavation easier as the machine simply pulls or rips out the blocks instead of cutting them. If the rock is very abrasive, or the pick consumption rate is more than 1-pick/m3, then roadheader excavation usually becomes uneconomical due to frequent bit changes coupled with increased machine vibrations and maintenance costs.A significant amount of effort has been placed over the years on increasing the ability of roadheaders to cut hard rock. Most of these efforts have focused on structural changes in the machines, such as increased weight, stiffer frames and more cutterhead power. Extensive field trials of these machines showed that the cutting tool is still the weakest point in hard rock excavation. Unless a drastic improvement is achieved in bit life, the true hard rock cutting is still beyond the realm of possibility with roadheaders. The Earth Mechanics Institute(EMI) of the Colorado School of Mines has been developing a new cutter technology, the Mini-Disc Cutter, to implement the hard rock cutting ability of disc cutters on roadheaders, as well as other types of mechanical excavators (Ozdemir et al, 1995). The full-scale laboratory tests with a standard transverse cutterhead showed that MiniDisc Cutters could increase the ability of the roadheaders for hard rock excavation while providing for lesser cutter change and maintenance stoppages. This new cutting technology holds great promise for application on roadheaders to extend their capability into economical excavation of hard rocks. In addition, using the mini-disc cutters, a drum miner concept has been developed by EMI for application to hard rock mine development. A picture of the drum miner during full-scale laboratory testing is shown in Figure-2.Figure-2: Drum Miner CutterheadFIELD PERFORMANCE DATABASEPerformance prediction is an important factor for successful roadheader application. This deals generally with machine selection, production rate and bit cost estimation. Successful application of roadheader technology to any mining operation dictates that accurate and reliable estimates are developed for attainable production rates and the accompanying bit costs. In addition, it is of crucial importance that the bit design and cutterhead layout is optimized for the rock conditions to be encountered during excavation.Performance prediction encompasses the assessment of instantaneous cutting rates, bit consumption rates and machine utilization for different geological units. The instantaneous cutting rate (ICR) is the production rate during actual cutting time, (tons or m3 / cutting hour). Pick consumption rate refers to the number of picks changed per unit volume or weight of rock excavated, (picks / m3 or ton). Machine utilization is the percentage of time used for excavation during the projectTable-I: Classification of the Information in the DatabaseThe Earth Mechanics Institute of the Colorado School of Mines jointly with the Mining Department of the Istanbul Technical University has established an extensive database related to the field performance of roadheaders with the objective of developing empirical models for accurate and reliable performance predictions. The database contains field data from numerous mining and civil construction projects worldwide and includes a variety of roadheaders and different geotechnical conditions.The empirical performance prediction methods are principally based on the past experience and the statistical interpretation of the previously recorded case histories. To obtain the required field data in an usable and meaningful format, a data collection sheet was prepared and sent to major contractors, owners, consultants, and roadheader manufacturers. In addition, data wasgathered from available literature on roadheader performance and through actual visits to job sites. This data collection effort is continuing.The database includes six categories of information, as shown in Table-I. The geological parameters in the database consist generally of rock mass and intact rock properties. The most important and pertinent rock mass properties contained in the database include Rock Quality Designation (RQD), bedding thickness, strike and dip of joint sets and hydrological conditions. The intact rock properties are uniaxial compressive strength, tensile strength, quartz content, texture and abrasivity. The rock formations are divided into separate zones to minimize the variations in the machine performance data to provide for more accurate analysis. This also simplifies the classification of the properties for each zone and the analysis of the field performance data.The major roadheader parameters included are the machine type (crawler mounted, shielded), machine weight, cutterhead type (axial, transverse), cutterhead power, cutterhead-lacing design, boom type (single, double, telescopic, articulated), and the ancillary equipment (i.e.grippers, automatic profiling, laser guidance, bit cooling and dust suppression by water jets, etc.).The operational parameters generally affect the performance of the excavator through machine utilization. The most important operational parameters include ground support, back up system (transportation, utility lines, power supply, surveying, etc.), ground treatment (water drainage, grouting, freezing, etc.), labor (availability and quality), and organization of the project (management, shift hours, material supply, etc.).CONCLUSIONSThe evaluation and analysis of the data compiled in the roadheader field performance database has successfully yielded a set of equations which can be used to predict the instantaneous cutting rate (ICR) and the bit consumption rate(BCR) for roadheaders. A good relationship was found to exist between these two parameters and the machine power (P), weight (W) and the rock compressive strength (UCS). Equations were developed for these parameters as a function of P, W and UCS. These equations were found mainly applicable to soft rocks of evaporatic origin. The current analysis is being extended to include harder rocks with or without joints to make the equations more universal. In jointed rock, the RQD value will be utilized as a measure of rockmass characteristics from a roadheader cuttability viewpoint. It is believed that these efforts will lead to the formulation of an accurate roadheader performance prediction model which can be used in different rock types where the roadheaders are economically applicable.中文译文掘进机在采矿和隧道业中的应用摘要掘进机为方便的挖掘硬岩而提供了一个独特的能力。
挖掘机中英文对照外文翻译文献

(文档含英文原文和中文翻译)中英文翻译外文文献A Summary of Small-size Excavators Home and Abroad I. The brief introduction of hydraulic excavatorParts such as the hydraulic excavator is by engine, hydraulic system and works device and walks device and electric control etc are formed. The hydraulic system is formed by hydraulic pump, control valve, hydraulic cylinder, hydraulic pressure motor, pipe route and fuel tank etc. The electric control system includes supervision dish, motor control system, pump brain and various kinds of sensor and solenoid valves etc. The hydraulic excavator is general by the work device and turns round the device and walks device three is mostly formed. According to his construction and use, we can differentiate : many kinds of typespressure, turns round entirely, not turns round entirely, utility version, mould for a special purpose, the joining with a hinge type and arm type stretched out and drawn back etc.The work device is directly accomplishing the device that excavates the assignment. It has been joined with a hinge by moves the arm, fights the pole and shovels the fill etc three parts. Moving that the arm rises and falls and the pole fought stretches out and draws back and shoveling fighting moves all with moving back and forth type two effect hydraulic cylinders control. In order to suit the needs of various difference construction school assignments, the hydraulic pressure excavator can be joined in marriage loading many kinds of work devices, if excavating and many kinds of school assignment machines and tools such as lifting job, loading, leveling, clamp and pushes soil and shock hammer etc.Turning round and walks the device is the organism of hydraulic pressure excavator, upper setting up power-on device and transmission system of turntable. The engine is the power supply of hydraulic pressure excavator, and adopts diesel oil will also can modify the electromotor in the convenient place mostly.The hydraulic drive system by way of the hydraulic pump with the engine the motive force transmission to hydraulic pressure motor and hydraulic cylinder etc actuator, the promotion work device moves, thus accomplishes the various school assignments. Take more PV-200's mould hydraulic pressure excavators of use in building site as the example. This machine adopts the type the opening center load of advanced version to be passed feeling system (OLSS). This system is with oblique of control type oblique the method of angle (export volume of flow ) variable plunger pump, and reduced the power delivery of engine, thus reduces the oil consumption burnt, and is one kind of saving energy mould system. The characteristic of this kind of hydraulic system is: the fixed torque is controlled, and it is unchangeable to keep the hydraulic pump drive torque, and year absolutely control can reduce the off-loading loss of school assignment time; Oil capacity is controlled, and the export volume of flow of hydraulic pump in the time of can reducing neutral gear and fine control reduces the power loss.The history of the first hand excavator was published up to now to have more than 130 years, and went through from the steam drive fill to turn round that the machinery turns round the developing the course step by step of the complete automatic hydraulic pressure excavator of excavator and application mechanical and electrical liquid integration technology to power drive and the internal-combustion engine drive in the time. Thehydraulic pressure to anti- the type hanging which shoveled machinery in the 1940’s, and developing out the pulling type at the initial stage of in the 1950’s with middle period in succession, to turn round the full hydraulic pressure of hydraulic pressure excavator and caterpillar tread type entirely mechanical. Initial stage the trial hydraulic pressure excavator is the hydraulic technique that adopts plane and machine tool, lacking the hydraulic pressure component that is suitable in the mechanical various operating modes, it is stable inadequately to make the quality, and necessary is not completely yet. From in the 1960’s, the hydraulic pressure excavator is entered the popularization and in vigorous development stage, and mechanical manufacturing plant and the breed of each country increases very fast, and the output is rapidly increased. 83% of the mechanical gross output was occupied to hydraulic pressure excavator output, and is close to 100% at present 1968-1970 certain period.ⅡSmall excavator development and its tendency20th century 80 ~ 90's small mechanical device in construction and soon in municipal engineering, transportation, pipeline has displayed abigger superiority and can rapidly develop. The small excavator forsaved the manpower, the physical resource in these projects makes thesmall excavator mainly to use in the city the constructionconstruction and generally left a bigger contribution,gradually became in the city construct ionto have the representative construction machinery.The small excavator development mainly relies on the urbanconstruction development, because city transformation, constructionconstruction more, the request construction time short, theconstruction machinery affects small, safe, the low pollution, theradius of gyration to the environment is small, is advantageous fortransports as well as has with the city scenery appearancecoordination outward appearance, the small excavator has satisfied thecity each kind of work request, can maximum limit display itsproductivity in the city narrow working space, therefore has theunique superiority.1. The development of small excavatorsThe small excavator mainly uses in the city the constructionconstruction and the general housing repairs and maintains and so onthe work, the request has the good operating performance and therotation performance.Initial small excavator by tire type primarily, because the tire typewalks the natural in the soft ground and the passing difference,afterwards gradually by the marching substitution, and in moved thearm strut organization place toorganism tocarry on swings, completed the trench sidewall excavation renovationwork behind, but this kind of small excavator excavation scope wassmall, cannot realize the material. Hereafter, the small excavator increased upside has rotated theorganization, has solved behind themetial and so on the problem, enhancedthe excavator operating performance, formed the small excavator thebasic structure. Afterwards, the small excavator in the radius ofgyration, behind the field of vision, moved aspect and so on armelevation angle, machine capability has the further improvement,develops for the present standard type.2.Technical progressesSmall excavator working conditions majority of in city, in order toprevent walks when damages the road surface, starts from the 80's touse the rubber caterpillar band, and gradually obtains thepopularization. A rubber caterpillar band heavy wheel is when theinternal iron circuit board the movement, the hard circuit board jointplace and the heavy wheel contact falls to the ground, becomes walksthe destruction road surface main reason. Before uses the width shapeiron circuit board, a rubber caterpillar band heavy wheel diameter isbigger, therefore when approaches the ground, this slit changes in abig way, creates the caterpillar band to the road surface destruction.The super small excavator use and the before same heavy wheel, onlywas the hard circuit board which in the caterpillar band used changesnarrowly, therefore when contacted the ground the slit changesslightly, reduced to the damage of ground.Rear area the small rotation excavator rotation rear part size isextremely small, in order to guarantee the excavator work thestability, must have the enough counterweight, and in does notincrease the mechanical weight under the premise, uses increases thecaterpillar band length and widens the chassis and so on the effectivemethod.But, the chassis width is transported the truck width the limit, forsolves this problem, has used ViCTAS in the super small excavator (Vio- Crawler Technology by Advanced Stability) the technology.fortablenessThe small excavator majority of seals cab, has not rained when thechair frequently drips wet by the rain seeps. In order to solve thisproblem, the use surface and the interior gather a peaceful fat rubberbody to manufacture has not sewn the seam the chair, cannot againfrom sew the seam place destruction, the durability also can enhance,becomes the complete waterproofing chair.Impels the small excavator market fast development the factor:mobile is flexible, extremely is suitable for work andso on cities each kind of pipelining, foundation construction, publicutilities as well as house service. The small excavator compactvolume, the special design enable its to carry on the work in theenvironment which the large-scale excavator is unable to construct.(2) The small excavator has the multi-purpose small excavator truemerit is it has multi-purpose. The small excavator can install manyauxiliary works machines and tools, like the installment brokenhammer, the hydraulic pressure pliers use in the lightweightdemolision work, installs a clamp to use in to eliminate the work,installs the drum, the plate uses in the trench to fill in buriesthe compaction, the installment turns on lathe digs drills uses in thedrill hole, the lift hook uses in to hoist up heavy item and so on.(3)The small excavator is advantageous for the transportation and oneof shift work location small hydraulic pressure excavator market rapidexpansion reasons should belong to its size and the weight. The smallexcavation function conveniently shifts in each job location, thesmall excavator does not need the large-scale trailer perhaps theheavy-duty truck carries on the transportation, the small transportmeans may deliver. Like this not only can facilitate thetransportation, but also may greatly reduce the machine the cartageexpense.(4) Small excavator bright work characteristic: The rear part radiusof turn for the zero design, causes the small excavator not to need inthe work space limited environment mean industry time excavatoroperator to consider the job location is, whether thus enable theoperator to have the obstacle to hinder the excavator the rotation tosuffice wholly absorbed to the scoop operation, this has alsoprevented around the job location the building as well as theexcavator own damage.(5) Invests the repayment rate to be high, the cost recycles quicklyThe small excavator price is cheap, the cost recycles quickly.Slightly digs take the 6t level as the example, American, the Europeandate brand machine price about 400,000 Yuan, South Korea's machineprice about 320,000 Yuan, the domestically produced machine price is30 ~ 320,000 Yuan some brands is lower; But the 20t level center digsthe price in 70 ~ 1 million Yuan. The higher investment repayment ratecauses the small excavator deeply the general center small earthworkconstruction to contract owner's welcome.4 Small excavators technological development tendenciesThe small excavator technological development complied with the globaldiversification job location the demand, has experienced more than 30years history successional variationtechnicalperformance, job function, work efficiency, security, environmentalprotection, energy conservation and maintenance maintenance had thelarge scale enhancement, has formed the quite consistent technicalstandard and the work standard. Mainly manifests in following severalaspects:(1) The tailless rotation and moves the arm deflection technology totake slightly digs the basic concept to move the arm deflection andthe tailless rotation function later period promotes in the 1990s facethe world market. Moves the arm deflection in the organism front part,but does not have the organization to be able to realize is locatednearby the lower part of wall the direct excavation work to havefrequently to move the fuselage. The tailless rotation structureapplication, causes it when the neck of land work does not need toworry the rear part the collision. The tailless rotation structuraldesign difficulty lies in rotates in the platform the generalarrangement, the dynamic system thermal equilibrium solution as wellas the entire machine stable solution. But moves the arm deflectionorganization the design difficulty to lie in an articulation positionthe determination and the hinge body manufacture technology.(2) New hydraulic control technologyThe new hydraulic control technology should have the work efficiencyhigh, the serviceability is good, has the good efficiency, may carryon the high efficiency, the powerful work. The new fluid environmentcompatibility presses the system not to shoulder the size theinfluence, completely needs the oil of the hydraulic pressure system, the current capacity accordingto the control handle scope distribution point, definitely may deferto operator's intention with ease to complete the work. At the sametime, because the engine load is small may avoid the current capacitythe senseless loss, can realize slightly moves the operation and thecompound operation. The new hydraulic control technology applicationalso can increase the dynamic output, enhances the work speed, reducesthe fuel consumption.(3)Security performanceHas the strict legal rule in the European market and the North Americamarket to the security, the equipment security performance can givethe operator to provide the relieved work the environment, enhancesoperator's security. The small excavator security performance mainlymanifests in the cab ROPS/FOPS design below, should satisfy theperformance requirement in the cab experiment:①May satisfy must energy absorption;② May satisfy must anti- load;(4) Environmental protection technologyMainly manifests in the power, the low oil consumption, cleanlydischarges the engine in the application. The new engine shouldsatisfy the American EPATier2 standard and the European EU standard,will cause the environmental pollution the compound to discharge thecontrol in the threshold. The new engine simultaneously reduced thevibration and the noise, is beneficial to the environmental protectionand operator's health.(5) Man-machine project technologyThe cab conforms to the man-machine engineering principle,internal spacious, field of vision open, modelling artistic, the easeof operation, reduces effort the measuring appliance demonstrationdirect-viewing, is accurate, can provide one kind of comfortableoperating environment to the pilot, fully reduces pilot's weariness.(6) Services the maintenance technologyMaintains from the current maintenance to the regular inspectionservice, the simplification operation is extremely essential, canenhance the machine the reliability, makes the machine throughout tomaintain the good condition. Must cause the daily inspection side, the realization not to need withthe aid of the tool as soon as to touch the type operation.Maintenance repair then quickly dnd simplely, but fast carries on theinternal spare part and the system inspection and the service. Moreover, in the design must fully consider prevents the machine theaccident damage.Such as the cowling, the guard plateguards against the collision structural design;Moves the arm hydraulic cylinder guard plate design; Fuel oil tank draw-offvalve; The independence bulldozes the board hydraulic pressure hosedesign; Waterproofing electric system design; In the work installmenthose sets at the design; X frame and halfway up the mountainsidecaterpillar band design; The engine machine oil filter elementreplacement time lengthens; Has forerunner system which the pipelinefilters; Dual spatially filters structure design and so on.5 ConclusionsSociety's development has a more tremendous influence to the smallexcavator, at present the overseas small excavator had the suitable development, like Carter other forces, company and so on Hitachi,small pine, Mitsubishi, the small excavator product has formed theseries, and in unceasingly carries on the development, the expandeduse, the increase appendix type. The domestic small excavatordevelopment has also obtained the certain result,中文译文国内外小型挖掘机发展综述一、液压挖掘机简介液压挖掘机是由发动机、液压系统、工作装置、行走装置和电气控制等部分组成。
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中国地质大学长城学院本科毕业设计外文资料翻译系别:工程技术系专业:机械设计制造及其自动化姓名:吴宝生学号: 052116152015 年 1 月 22 日国内外小型挖掘机发展综述1液压挖掘机简介液压挖掘机是由发动机、液压系统、工作装置、行走装置和电气控制等部分组成。
液压系统由液压泵、控制阀、液压缸、液压马达、管路、油箱等组成。
电气控制系统包括监控盘、发动机控制系统、泵控制系统、各类传感器、电磁阀等。
液压挖掘机一般由工作装置、回转装置和行走装置三大部分组成。
根据其构造和用途可以区分为:履带式、轮胎式、步履式、全液压、半液压、全回转、非全回转、通用型、专用型、铰接式、伸缩臂式等多种类型。
工作装置是直接完成挖掘任务的装置。
它由动臂、斗杆、铲斗等三部分铰接而成。
动臂起落、斗杆伸缩和铲斗转动都用往复式双作用液压缸控制。
为了适应各种不同施工作业的需要,液压挖掘机可以配装多种工作装置,如挖掘、起重、装载、平整、夹钳、推土、冲击锤等多种作业机具。
回转与行走装置是液压挖掘机的机体,转台上部设有动力装置和传动系统。
发动机是液压挖掘机的动力源,大多采用柴油要在方便的场地,也可改用电动机。
液压传动系统通过液压泵将发动机的动力传递给液压马达、液压缸等执行元件,推动工作装置动作,从而完成各种作业。
以工地使用较多的PV-200型液压挖掘机为例。
该机采用改进型的开式中心负荷传感系统(OLSS)。
该系统用控制斜盘式变量柱塞泵斜盘角(输出流量)的方法,减少了发动机的功率输出,从而减少燃油消耗,是一种节能型系统。
这种液压系统的特点是:定转矩控制,能维持液压泵驱动转矩不变,载断控制,可以减少作业时间的卸荷损失;油量控制,可减少空挡和小调控制时液压泵的输出流量,减少功率损失。
械到电力驱动和内燃机驱动回转挖掘机、应用机电液一体化技术的全自动液压挖掘机的逐步发展过程。
由于液压技术的应用,20世纪40年代有了在拖拉机上配装液压反铲的悬挂式机械,20世纪50年代初期和中期相继研制出拖式全回转液压挖掘机和履带式全液压机械。
初期试制的液压挖掘机是采用飞机和机床的液压技术,缺少适用于机械各种工况的液压元件,制造质量不够稳定,配套件也不齐全。
从20世纪60年代起,液压挖掘机进入推广和蓬勃发展阶段,各国机械制造厂和品种增加很快,产量猛增。
1968-1970年间,液压挖掘机产量已占机械总产量的83%,目前已接近100%。
2小型挖掘机的发展及其趋势20 世纪80~90 年代小型挖掘机在市政工程、交通、管道等施工中发挥了较大优势并得以迅速发展。
它在城市的土建施工工程中为节省人力、物力出了较大贡献 , 逐步成为城市施工中具有代表性的施工机械。
小型挖掘机的发展主要依赖于城市建设的发展,由于城市的改造、建设施工较多,要求施工时间短、施工机械对周围环境影响小、安全、低污染、回转半径小、便于运输以及具有与城市景色相协调的外观,小型挖掘机满足了城市各种作业要求,在城市狭窄的工作空间内能够最大限度地发挥其生产能力,因此具有独特的优越性。
1. 小型挖掘机的发展小型挖掘机在城市中主要用于土建施工及一般住宅修整等工作,要求具有良好工作性能和回转性能。
最初的小型挖掘机以轮胎式为主,由于轮胎式在软地面的行走性和通过性差,后来逐渐被履带式替代,并在动臂支撑机构处增加了回转机构,使整个工作装置能相对机体进行左右摆动,以完成沟道侧壁挖掘整修工作,但这种小型挖掘机挖掘范围小、不能实现后部卸料。
此后,小型挖掘机增加了上部回转机构,解决了后部卸料等问题,提高了挖掘机的工作性能,形成小型挖掘机的基本结构。
后来,小型挖掘机在回转半径、后部视野、动臂仰角、机械性能等方面得到进一步改善,发展为现在的标准型。
2. 技术的进步小型挖掘机工作环境大部分在城市,为了防止行走时损坏路面,从 80 年代开始使用橡胶履带 ,并逐步得到普及。
橡胶履带的支重轮是在内部铁芯板上运动 , 铁芯板接缝处与支重轮接触落地时,成为行走破坏路面的主要原因。
以前使用宽形铁芯板,橡胶履带的支重轮直径较大,因此在接近地面时,这个缝隙变大,造成履带对路面的破坏。
超级小型挖掘力小,减小了对地面的损坏。
后方小回转型挖掘机的回转尾部尺寸非常小,为了确保挖掘机工作的稳定性,必须有足够的配重,并在不增加机械重量的前提下,采用增大履带长度及加宽车体等有效方法。
但是,车体宽度受运输卡车宽度的限制,为解决这个问题,在超级小型挖掘机中采用ViCTAS (Vio - Crawler Technology by Advanced Stability )技术。
3. 舒适性小型挖掘机大部分没有封闭的驾驶室, 下雨时座椅常常被雨淋湿而渗水。
为了解决这一问题,使用表面与内部聚安脂橡胶一体制作的没有缝制缝的座椅 ,不会再从缝制缝处破坏 ,耐久性也得以提高,成为完全防水型座椅。
3推动小型挖掘机市场快速发展的因素(1) 小型挖掘机具有的广泛适用性小型挖掘机体积小、机动灵活,非常适用于城镇的各种管道铺设、基础施工、公用事业以及房屋维修等作业。
小型挖掘机紧凑的体积、特殊的设计使其能够在大型挖掘机无法施工的环境中进行作业。
(2) 小型挖掘机具有的多功能性小型挖掘机的真正优点是它具有多功能性。
小型挖掘机能够安装许多辅助作业机具,如安装破碎锤、液压钳用于轻量级的拆除作业,安装夹钳用于清除作业,安装滚筒、平板夯用于沟槽的填埋压实,安装旋挖钻具用于钻孔,吊钩用于起吊重物等等。
(3) 小型挖掘机便于运输和转移作业场地小型液压挖掘机市场迅速扩张的原因之一应归于它的尺寸和重量。
小型挖掘机能方便地在各个施工现场间转移,小型挖掘机无需大型拖车或是重型卡车进行运输,小型的运输工具就可运载。
这样不但能够方便运输,还可以大大降低机器的运输费用。
(4) 小型挖掘机鲜明的作业特点:尾部旋转半径为零的设计,使得小型挖掘机在作业空间有限的环境下作业时挖掘机操作人员无须考虑施工现场是,从而使操作人员能否有障碍物阻碍挖掘机的转动够更专心于铲斗的操作,这也防止了施工现场周围建筑物以及挖掘机自身的损坏。
(5) 投资回报率高、成本回收快小型挖掘机的价格便宜,成本回收快。
以6t级小挖为例,美、欧日品牌机的价格在四十万元左右,韩国的机器价格在三十二万元左右,国产机器价格为30~32 万元,一些品牌价格较低;但20t级中心挖掘机价格在70 万~100万元。
较高的投资回报率使得小型挖掘机深受广大中小土方工程施工承包人的欢迎。
4小型挖掘机的技术发展趋势小型挖掘机的技术发展顺应全球多样化的工作位置要求,经历了超过30年的历史成功的变化过程,经过不断的改进完善,在技术性能等方面,工作职能,工作效率,安全,环保,节能,维修保养有了大幅度的提高,形成了比较一致的技术标准和工作标准。
主要体现在以下几个方面:(1)无尾的旋转和移动臂偏转技术把小挖的基本概念动臂偏转和无尾旋转的功能,促进在上世纪90年代后期,面对世界市场。
动臂偏转在机体前部,但没有组织能够实现位于壁直接开挖工作要经常移动机身下部附近。
无尾回转结构的应用,使土地工作时颈部不必担心后部碰撞。
无尾回转结构设计的难点在于在平台总布置的旋转时,动力系统热平衡的解决方案以及整机的稳定的解决方案。
但动臂偏转机构的设计难点在于发音位置和铰链体制造技术的测定。
(2)适用性好,具有良好的效率,可以进行效率高,强大的工作。
新的流体环境兼容机系统不承担尺寸的影响,需要液压系统油,根据控制处理范围分布点的电流容量,完全可以按照操作者的意图,轻松完成工作。
同时,由于发动机负荷小可以避免无谓的损失电流的能力,可以实现轻微移动操作和复合操作。
新型液压控制技术的应用还可以增加动力输出,提高了工作速度,降低燃料消耗。
(3)安全性能在欧洲市场,严格的法律规则和北美国市场的安全,设备安全性能可以给经营者提供安心的工作环境,安全。
在驾驶室ROPS/FOPS设计以下的小型挖掘机主要应满足安全性能,驾驶室中的实验性能要求:①可满足必须的能量吸收;②可以满足一定抗负荷;③乘员安全区足够大。
(4)环境保护技术主要体现在功率,低油耗,清洁排放发动机的应用。
新的发动机应该满足美国epatier2标准及欧洲欧盟标准,会造成环境污染的化合物在阈值控制放电。
新的引擎的同时减少振动和噪声,有利于保护环境和操作者的健康。
(5)人机工程技术驾驶室符合人机工程学原理,内部宽敞,视野开阔,场造型美观,操作方便,省力的仪表显示直观,准确,能提供一种舒适的操作环境为先导,充分降低了驾驶员的疲劳。
(6)服务维修技术从目前的维修维护定期检查服务,简化操作是非常必要的,可以提高机器的可靠性,使机器始终保持良好的状态。
要使日常检查侧操作。
维修然后迅速而快速的进行内部零部件与系统的检查与维修。
此外,在设计中必须充分考虑防止机器损坏的事故。
如罩,护板的防碰撞结构设计;动臂液压缸护板设计;燃料油罐排水阀;独立的推土板液压软管设计;防水电气系统设计工作;在安装设置在设计;X架和半山腰侧卡特彼勒带设计;发动机机油滤芯的更换时间延长;具有先进的系统,管道过滤器;双空间滤波器的结构设计等。
5结论小型挖掘机对社会的发展有较大影响,目前海外小型挖掘机有了相当大的发展,像卡特其军队,日立公司等,小松树,三菱,小型挖掘机产品已形成系列,并在不断进行发展,扩大使用,增加附录型。
国内小型挖掘机的发展也取得了一定的效果,但都需要进一步改进和完善的技术和生产。
外文原文A Summary of Small-size Excavators Home and Abroad1 The brief introduction of hydraulic excavatorParts such as the hydraulic excavator is by engine, hydraulic system and works device and walks device and electric control etc are formed. The hydraulic system is formed by hydraulic pump, control valve, hydraulic cylinder, hydraulic pressure motor, pipe route and fuel tank etc. The electric control system includes supervision dish, motor control system, pump brain and various kinds of sensor and solenoid valves etc. The hydraulic excavator is general by the work device and turns round the device and walks device three is mostly formed. According to his construction and use, we can differentiate : many kinds of types such as caterpillar tread type, walk type, full hydraulic pressure, half hydraulic pressure, turns round entirely, not turns round entirely, utility version, mould for a special purpose, the joining with a hinge type and arm type stretched out and drawn back etc.The work device is directly accomplishing the device that excavates the assignment. It has been joined with a hinge by moves the arm, fights the pole and shovels the fill etc three parts. Moving that the arm rises and falls and the pole fought stretches out and draws back and shoveling fighting moves all with moving back and forth type two effect hydraulic cylinders control. In order to suit the needs of various difference construction school assignments, the hydraulic pressure excavator can be joined in marriage loading many kinds of work devices, if excavating and many kinds of school assignment machines and tools such as lifting job, loading, leveling, clamp and pushes soil and shock hammer etc.Turning round and walks the device is the organism of hydraulic pressure excavator, upper setting up power-on device and transmission system of turntable. The engine is the power supply of hydraulic pressure excavator, and adopts diesel oil will also can modify the motor in the convenient place mostly.The hydraulic drive system by way of the hydraulic pump with the engine the motive promotion work device moves, thus accomplishes the various school assignments. Take more PV-200's could hydraulic pressure excavators of use in building site as the example. This machine adopts the type the opening center load of advanced version to be passed feeling system (OLSS). This system is with oblique of control type oblique the method of angle (export volume of flow ) variable plunger pump, and reduced the power delivery of engine,thus reduces the oil consumption burnt, and is one kind of saving energy could system. The characteristic of this kind of hydraulic system is: the fixed torque is controlled, and it is unchangeable to keep the hydraulic pump drive torque, and year absolutely control can reduce the off-loading loss of school assignment time; Oil capacity is controlled, and the export volume of flow of hydraulic pump in the time of can reducing neutral gear and fine control reduces the power loss.The history of the first hand excavator was published up to now to have more than 130 years, and went through from the steam drive fill to turn round that the machinery turns round the developing the course step by step of the complete automatic hydraulic pressure excavator of excavator and application mechanical and electrical liquid integration technology to power drive and the internal-combustion engine drive in the time. The application owing to the hydraulic technique had to join in marriage on the tractor loading hydraulic pressure to anti- the type hanging which shoveled machinery in the 1940’s, and developing out the pulling type at the initial stage of in the 1950’s with middle period in succession, to turn round the full hydraulic pressure of hydraulic pressure excavator and caterpillar tread type entirely mechanical. Initial stage the trial hydraulic pressure excavator is the hydraulic technique that adopts plane and machine tool, lacking the hydraulic pressure component that is suitable in the mechanical various operating modes, it is stable inadequately to make the quality, and necessary is not completely yet. From in the 1960’s, the hydraulic pressure excavator is entered the popularization and in vigorous development stage, and mechanical manufacturing plant and the breed of each country increases very fast, and the output is rapidly increased. 83% of the mechanical gross output was occupied to hydraulic pressure excavator output, and is close to 100% at present 1968-1970 certain period.2 Small excavator development and its tendency20th century 80 ~ 90's small mechanical device in construction and soon in municipal engineering, transportation, pipeline has displayed a bigger superiority and can rapidly makes the small excavator mainly to use in the city the construction and generally left a bigger contribution,gradually became in the city construct into have the representative construction machinery.The small excavator development mainly relies on the urban construction development, because city transformation, construction more, the request construction time short, the construction machinery affects small, safe, the low pollution, the radius of gyration to the environment is small, is advantageous for transports as well as has with the city sceneryappearance coordination outward appearance, the small excavator has satisfied the city each kind of work request, can maximum limit display its productivity in the city narrow working space, therefore has the unique superiority.1. The development of small excavatorsThe small excavator mainly uses in the city the construction and the general housing repairs and maintains and so on the work, the request has the good operating performance and the rotation performance.Initial small excavator by tire type primarily, because the tire type walks the natural in the soft ground and the passing difference,afterwards gradually by the marching substitution, and in moved them strut organization place to increase the rotation organization about, enabled the entire work equipment the relative organism to carry on swings, completed the trench sidewall excavation renovation work behind, but this kind of small excavator excavation scope was small, cannot realize the material. Hereafter, the small excavator increased upside has rotated the organization, has solved behind the metial and so on the problem, enhanced the excavator operating performance, formed the small excavator the basic structure. Afterwards, the small excavator in the radius of gyration, behind the field of vision, moved aspect and so on arm elevation angle, machine capability has the further improvement,develops for the present standard type.2.Technical progressesSmall excavator working conditions majority of in city, in order top revent walks when damages the road surface, starts from the 80's to use the rubber caterpillar band, and gradually obtains the popularization. A rubber caterpillar band heavy wheel is when the internal iron circuit board the movement, the hard circuit board join place and the heavy wheel contact falls to the ground, becomes walks the destruction road surface main reason. Before uses the width shape iron circuit board, a rubber caterpillar band heavy wheel diameter is bigger, therefore when approaches the ground, this slit changes in a big way, creates the caterpillar heavy wheel, only was the hard circuit board which in the caterpillar band used changes narrowly, therefore when contacted the ground the slit changes slightly, reduced to the damage of ground.Rear area the small rotation excavator rotation rear part size is extremely small, in order to guarantee the excavator work the stability, must have the enough counterweight, and in does the mechanical weight under the premise, uses increases the caterpillar band length and widens the chassis and so on the effective method.But, the chassis width is transported the truck width the limit, for solves this problem, has used VCTAS in the super small excavator (Vio- Crawler Technology by Advanced Stability) the technology.fortablenessThe small excavator majority of seals cab, has not rained when the chair frequently drips wet by the rain seeps. In order to solve this problem, the use surface and the interior gather a peaceful fat rubber body to manufacture has not sewn the seam the chair, cannot again from sew the seam place destruction, the durability also can enhance,becomes the complete waterproofing chair.3 Impels the small excavator market fast development the factor(1) The small excavator has the widespread serviceable small excavator volume small, mobile is flexible, extremely is suitable for work and so on cities each kind of pipe , foundation construction, public utilities as well as house service. The small excavator compact volume, the special design enable its to carry on the work in the environment which the large-scale excavator is unable to construct.(2) The small excavator has the multi-purpose small excavator true merit is it has multi-purpose. The small excavator can install man works machines and tools, like the installment broken hammer, the hydraulic pressure pliers use in the lightweight on work, installs a clamp to use in to eliminate the work,installs the drum, the plate uses in the trench to fill in buries the compaction, the installment turns on lathe digs drills uses in the drill hole, the lift hook uses in to hoist up heavy item and so on.(3)The small excavator is advantageous for the transportation and one of shift work location small hydraulic pressure excavator market rapid expansion reasons should belong to its size and the weight. The small excavation function conveniently shifts in each job location, the small excavator does not need the large-scale trailer perhaps the heavy-duty truck carries on the transportation, the small transport means may deliver. Like this not only can facilitate(4) Small excavator bright work characteristic: The rear part turn for the zero design, causes the small excavator not to need in the work space limited environment mean industry time excavator operator to consider the job location is, whether thus enable the operator to have the obstacle to hinder the excavator the rotation to suffice wholly absorbed to the scoop operation, this has also prevented around the job location the building as well as the excavator own damage.(5) Invests the repayment rate to be high, the cost recycles quicklyThe small excavator price is cheap, the cost recycles quickly.Slightly digs take the 6t level as the example, American, the European date brand machine price about 400,000 Yuan, South Korea's machine price about 320,000 Yuan, the domestically produced machine price is30 ~ 320,000 Yuan some brands is lower; But the 20t level center digs the price in 70 ~ 1million Yuan. The higher investment repayment rate causes the small excavator deeply the general center small earth work construction to contract owner's welcome.4 Small excavators technological development tendenciesThe small excavator technological development complied with the global diversification job location the demand, has experienced more than 30years history success variation process, passes through the unceasing improvement consummation, in aspect and so on technical performance, job function, work efficiency, security, environmental protection, energy conservation and maintenance maintenance had the large scale enhancement, has formed the quite consistent technical standard and the work standard. Mainly manifests in following several aspects:(1) The tailless rotation and moves the arm deflection technology to take slightly digs the basic concept to move the arm deflection and the tailless rotation function later period promotes in the 1990s face the world market. Moves the arm deflection in the organism front part,but does not have the organization to be able to realize is located nearby the lower part of wall the direct excavation work to have frequently to move the fuselage. The tailless rotation structure application, causes it when the neck of land work does not need to worry the rear part the collision. The tailless rotation structural design difficulty lies in rotates in the platform the general arrangement, the dynamic system thermal equilibrium solution as well as the entire machine stable solution. But moves the arm deflection organization the design difficulty to lie in an articulation position the determination and the hinge body manufacture technology.(2) Serviceability is good, has the good efficiency, may carry on the high efficiency, the powerful work. The new fluid environment compatibility presses the system not to shoulder the size the influence, completely needs the oil of the hydraulic pressure system, the current capacity according to the control handle scope distribution point, definitely may defer to operator's intention with ease to complete the work. At the same time, because the engine load is small may avoid the current capacity the senseless loss, can realize slightly moves the operation and the compound operation. The new hydraulic control technology application also can increase the dynamic output, enhances the work speed, reduces the fuel consumption.(3)Security performanceHas the strict legal rule in the European market and the North America market to the security, the equipment security performance can give the operator to provide the relievedwork the environment, security. The small excavator security performance main in the cab ROPS/FOPS design below, should satisfy the performance requirement in the cab experiment:①May satisfy must energy absorption;②May satisfy must anti- load;③The crew member safety zone enough is big.(4) Environmental protection technologyMainly manifests in the power, the low oil consumption, cleanly discharges the engine in the application. The new engine should satisfy the American EPATier2 standard and the European EU standard,will cause the environmental pollution the compound to discharge the control in the threshold. The new engine simultaneously reduced the vibration and the noise, is beneficial to the environmental protection and operator's health.(5) Man-machine project technologyThe cab conforms to the man-machine engineering principle,internal spacious, field of vision open, modeling artistic, the ease of operation, reduces effort the measuring appliance demonstration direct-viewing, is accurate, can provide one kind of comfortable operating environment to the pilot, fully reduces pilot's weariness.(6) Services the maintenance technologyMaintains from the current maintenance to the regular inspection service, the simplification operation is extremely essential, can enhance the machine the reliability, makes the machine throughout to maintain the good condition. Must cause the daily inspection side operation.Maintenance repair then quickly but fast carries on the internal spare part and the system inspection and the service. Moreover, in the design must fully consider prevents the machine the accident damage.Such as the cowling, the guard plate guards against the collision structural design;Moves the arm hydraulic cylinder guard plate design; Fuel oil tank draw-off valve; The independence bulldozes the board hydraulic pressure hose design; Waterproofing electric system design; In the work install sets at the design; X frame and halfway up the mountain side caterpillar band design; The engine machine oil filter element replacement time lengthens; Has forerunner system which the pipeline filters; Dual spatially filters structure design and so on.5 ConclusionsSociety's development has a more tremendous influence to the small excavator, at present the overseas small excavator had the suitable development, like Carter other forces, company and so on Hitachi,small pine, Mitsubishi, the small excavator product has formedthe series, and in unceasingly carries on the development, the expanded use, the increase appendix type. The domestic small excavator development has also obtained the certain result, but all needs further to improve and the consummation in the technology and the production.。