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机械专业外文翻译中英文翻译

机械专业外文翻译中英文翻译
机械专业外文翻译中英文翻译

外文翻译

英文原文

Belt Conveying Systems Developme nt of driv ing system Among the methods of material conveying employed, belt conveyors play a very

importa nt part in the reliable carry ing of material over long distances at competitive cost . Conveyor systems have becomelarger and more complex and drive systems have also bee n going through a process of evolution and will continue to do so.

Nowadays bigger belts require more

power and have brought the n eed for larger in dividual drives as well as multiple

drives such as 3 drives of 750 kW for one belt(this is the case for the conveyor drives in ChengzhuangMine) . The ability to control drive acceleration torque is critical to belt conveyors ' performanee . An

efficient drive system should be able to provide smooth, soft starts while maintaining belt tensions within the specified safe limits . For load sharing on multiple drives .

torque and speed control are also important con sideratio ns in the drive system ' s desig n . Due to the adva nces in conv eyor drive con trol tech no logy , at prese nt many more

reliable . Cost-effective and performance-driven conveyor drive systems covering a wide range of power are available for customers ' choices ⑴.

1 An alysis on conv eyor drive tech no logies

1. 1 Direct drives

Full-voltage starters . With a full-voltage starter design , the conveyor head shaft is direct-coupled to the motor through the gear drive . Direct full-voltage starters are adequate for relatively low-power, simple-profile conveyors . With direct fu11-voltage starters . no control is provided for various conveyor loads and . depe nding on the ratio betwee n full- and no -load power requireme nts , empty starti ng times can be three or four times faster tha n full load . The maintenance-free starting system is simple , low-cost and very reliable . However, they

cannot control starting torque and maximum stall torque ;therefore . they are limited to the low-power, simple-profile con veyor belt drives .

Reduced-voltage starters . As conv eyor power requireme nts in crease ,

con trolli ng the applied motor torque duri ng the accelerati on period becomes increasingly important . Because motor torque 1s a function of voltage

, motor voltage must be con trolled . This can be achieved through reduced-voltage starters by

employi ng a silic on con trolled rectifier(SCR) . A commorstarti ng method with

SCR reduced-voltage starters is to apply low voltage in itially to take up

conveyor belt slack . and then to apply a timed linear ramp up to full voltage can provide

better starti ng torque whe n comb ined with the SCR starters, which are available in sizes up to 750 KW

Wound rotor in duct ion motors . Wound rotor in duct ion motors are conn ected directly to the drive system reducer and are a modified con figurati on of a

sta ndard ACi nductio n motor . By in sert ing resista nee in series with the motor ' s

rotor windings . the modified motor con trol system con trols motor torque . For

conv eyor starti ng , resista nee is placed in series with the rotor for low in itial torque . As the conv eyor accelerates , the resista nee is reduced slowly to maintain a con sta nt accelerati on torque . On multiple-drive systems . an exter nal slip

resistor maybe left in series with the rotor windings to aid in load sharing . The motor

systems have a relatively simple design . However, the control systems for these can be highly complex , because they are based on computer control of the resista nee switch ing . Today , the majority of c on trol systems are custom desig ned to meet a conveyor system ' s particular specifications . Woundrotor motors are

appropriate for systems requiri ng more tha n 400 kW .

DC motor . DC motors . available from a fraction of thousands of kW

, are designed to deliver constant torque below base speed and constant kWabove base speed to the maximumallowable revolutions per minute(r/min) . with the majority

of con veyor drives, a DCsh unt woun dmotor is used . Where in the motor ' s rotat ing

and belt speed . However, this starti ng method will not produce constant conveyor belt accelerati on . When acceleration is complete .the SCRs, which control the applied voltage to the electric motor . are locked in full con duct ion. providi ng fu11-li ne voltage to the motor . Motors with higher

torque and pull — up torque ,

armature is conn ected externally . The most com mon tech no logy for con troll ing DC drives is a SCR device . which allows for continual variable-speed operation . The DCdrive system is mechanically simple, but can include complex custom-designed electronics to monitor and control the complete system . This system option is expensive in comparison to other soft-start systems . but it

is a reliable, cost-effective drive in applications in which torque,1oad sharing and variable speed are primary con siderati ons . DCmotors gen erally are used with higher-power conveyors , including complex profile conveyors with multiple-drive systems, booster tripper systems needing belt tension control and conveyors requiri ng a wide variable-speed range

1. 2 Hydrokinetic coupling

Hydrokinetic couplings , commonlyreferred to as fluid couplings . are composed of three basic elements; the driven impeller, which acts as a centrifugal pump the driv ing hydraulic turb ine known as the runner and a cas ing that en closes the two power components . Hydraulic fluid is pumped from the driven impeller to the driving runner, producing torque at the driven shaft . Because circulating hydraulic fluid produces the torque and speed , no mechanical connection is required between the driving and driven shafts . The power produced by this coupling is based on the circulated fluid ' s amount and density and the torque

in proporti on to in put speed. Because the pump ing acti on with in the fluid coupli ng depends on centrifugal forces . the output speed is less than the in put

speed. Referred to as slip . this normally is between 1% and 3% Basic hydrokinetic coupli ngs are available in con figurati ons from fracti onal to several thousa nd kW .

Fixed-fill fluid couplings . Fixed-fill fluid couplings are the most commonly used soft-start devices for conv eyors with simpler belt profiles and limited conv ex/c on cave sect ions

. They are relatively

simple,1ow-cost,reliable,mai ntenance free devices that provide excelle nt soft

starti ng results to the majority of belt conv eyors in use today .

Drai nable-fluid coupli ngs work on the same Variable-fill drain coupli ngs

principle as fixed-fill couplings . The coupling ' s impellers are mounted on the

ACmotor and the runners on the driven reducer high-speed shaft . Housing mounted to the drive base encloses the working circuit . The coupling ' s rotating casing contains bleed-off orifices that continu ally allow fluid to exit the worki ng circuit into a separate hydraulic reservoir . Oil from the reservoir is pumped through a heat excha nger to a sole no id-operated hydraulic valve that con trols the filling of the fluid coupling . To control the starting torque of a

single-drive conveyor system, the ACmotor current must be monitored to provide feedback to the solenoid control valve . Variable fill drain couplings are used

in mediumto high-kW conveyor systems and are available in sizes up to thousands of kW . The drives can be mechanically complex and depending on the control parameters . the system can be electronically intricate . The drive system cost

is medium to high, depe nding upon size specified .

Hydrokinetic scoop control drive . The scoop control fluid coupling consists of the three standard fluid coupling components : a driven impeller, a driving

runner and a casing that encloses the working circuit . The casing is fitted with fixed orifices that bleed a predeterm ined amount of fluid in to a reservoir . When the scoop tube is fully exte nded in to the reservoir, the coupli ng is 100 perce nt filled . The scoop tube, extending outside the fluid coupling , is positioned using an electric actuator to en gage the tube from the fully retracted to the fully en gaged positi on . This con trol provides reas on ably smooth accelerati on rates . to but the computer-based control system is very complex . Scoop control couplings are applied on conveyors requiring single or multiple drives from l50 kWto 750

kW.

1 . 3 Variable-freque ncy con trol(VFC)

Variable freque ncy con trol is also one of the direct drive methods . The

机械手机械设计论文中英文资料对照外文翻译

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《机械工程专业英语教程》课文翻译

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机械专业外文翻译(中英文翻译)

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机械专业中英文对照(完整版)1

机械专业英语词汇 陶瓷ceramics 合成纤维synthetic fibre 电化学腐蚀electrochemical corrosion 车架automotive chassis 悬架suspension 转向器redirector 变速器speed changer 板料冲压sheet metal parts 孔加工spot facing machining 车间workshop 工程技术人员engineer 气动夹紧pneuma lock 数学模型mathematical model 画法几何descriptive geometry 机械制图Mechanical drawing 投影projection 视图view 剖视图profile chart 标准件standard component 零件图part drawing 装配图assembly drawing 尺寸标注size marking 技术要求technical requirements 刚度rigidity 内力internal force 位移displacement 截面section 疲劳极限fatigue limit 断裂fracture 塑性变形plastic distortion 脆性材料brittleness material 刚度准则rigidity criterion 垫圈washer 垫片spacer 直齿圆柱齿轮straight toothed spur gear 斜齿圆柱齿轮helical-spur gear 直齿锥齿轮straight bevel gear 运动简图kinematic sketch 齿轮齿条pinion and rack 蜗杆蜗轮worm and worm gear 虚约束passive constraint 曲柄crank 摇杆racker 凸轮cams 共轭曲线conjugate curve 范成法generation method 定义域definitional domain 值域range 导数\\微分differential coefficient 求导derivation 定积分definite integral 不定积分indefinite integral 曲率curvature 偏微分partial differential 毛坯rough 游标卡尺slide caliper 千分尺micrometer calipers 攻丝tap 二阶行列式second order determinant 逆矩阵inverse matrix 线性方程组linear equations 概率probability 随机变量random variable 排列组合permutation and combination 气体状态方程equation of state of gas 动能kinetic energy 势能potential energy 机械能守恒conservation of mechanical energy 动量momentum 桁架truss 轴线axes 余子式cofactor 逻辑电路logic circuit 触发器flip-flop 脉冲波形pulse shape 数模digital analogy 液压传动机构fluid drive mechanism 机械零件mechanical parts 淬火冷却quench 淬火hardening 回火tempering 调质hardening and tempering 磨粒abrasive grain 结合剂bonding agent 砂轮grinding wheel 后角clearance angle 龙门刨削planing 主轴spindle

机械专业英文翻译

启动轴starting axle 启动齿轮starting gear 启动棘轮starting ratchet wheel 复位弹簧restoring, pull back spring 弹簧座spring seating 摩擦簧friction spring 推力垫圈thrust washer 轴挡圈axle bumper ring 下料filling 切断cut 滚齿机gear-hobbing machine 剪料机material-shearing machine 车床lathe 拉床broaching machine 垂直度verticality, vertical extent 平行度 parallelism同心度 homocentricity 位置度position 拉伤pulling damage 碰伤bumping damage 缺陷deficiency 严重缺陷severe deficiency 摩擦力friction 扭距twist 滑动glide 滚动roll 打滑skid 脱不开can’t seperate 不复位can’t restore 直径diameter M值= 跨棒距test rod span 公法线common normal line 弹性elasticity 频率特性frequency characteristic 误差error 响应response 定位allocation 机床夹具jig 动力学dynamic 运动学kinematic 静力学static 分析力学analyse mechanics 拉伸pulling 压缩hitting 机床machine tool 刀具cutter 摩擦friction 联结link 传动drive/transmission 轴shaft 剪切shear 扭转twist 弯曲应力bending stress 三相交流电three-phase AC 磁路magnetic circles 变压器transformer 异步电动机asynchronous motor 几何形状geometrical 精度precision 正弦形的sinusoid 交流电路AC circuit 机械加工余量machining allowance 变形力deforming force 变形deformation 电路circuit 半导体元件semiconductor element 拉孔broaching 装配assembling 加工machining 液压hydraulic pressure 切线tangent 机电一体化mechanotronics mechanical-electrical integration 稳定性stability 介质medium 液压驱动泵fluid clutch 液压泵hydraulic pump 阀门valve 失效invalidation 强度intensity 载荷load 应力stress 安全系数safty factor 可靠性reliability 螺纹thread 螺旋helix 键spline 销pin 滚动轴承rolling bearing 滑动轴承sliding bearing 弹簧spring 制动器arrester brake 十字结联轴节crosshead 联轴器coupling 链chain 皮带strap 精加工finish machining 粗加工rough machining 变速箱体gearbox casing 腐蚀rust 氧化oxidation 磨损wear 耐用度durability 机械制图 Mechanical drawing 投影projection 视图view 剖视图profile chart 标准件standard component 零件图part drawing 装配图assembly drawing 尺寸标注size marking 技术要求 technical requirements 刚度rigidity 内力internal force 位移displacement 截面section 疲劳极限fatigue limit 断裂fracture 塑性变形plastic distortion 脆性材料brittleness material 刚度准则rigidity criterion 垫圈washer 垫片spacer 直齿圆柱齿轮 straight toothed spur gear 斜齿圆柱齿轮 helical-spur gear 直齿锥齿轮 straight bevel gear 运动简图kinematic sketch 齿轮齿条pinion and rack 蜗杆蜗轮worm and worm gear 虚约束passive constraint 曲柄crank 摇杆racker 凸轮cams 反馈feedback 发生器generator 直流电源DC electrical source 门电路gate circuit 外圆磨削external grinding 内圆磨削internal grinding 平面磨削plane grinding 变速箱gearbox 离合器clutch 绞孔fraising 绞刀reamer

(机械制造行业)机械英文翻译

英文翻译 机械设计 一台完整机器的设计是一个复杂的过程。机械设计是一项创造性的工作。设计工程师不仅在工作上要有创造性,还必须在机械制图、运动学、工程材料、材料力学和机械制造工艺学等方面具有深厚的基础知识。 Machine Design The complete design of a machine is a complex process. The machine design is a creative work. Project engineer not only must have the creativity in the work, but also must in aspect and so on mechanical drawing, kinematics, engineerig material, materials mechanics and machine manufacture technology has the deep elementary knowledge. 任何产品在设计时第一步就是选择产品每个部分的构成材料。许多的材料被今天的设计师所使用。对产品的功能,它的外观、材料的成本、制造的成本作出必要的选择是十分重要的。对材料的特性必须事先作出仔细的评估。 One of the first steps in the design of any product is to select the material from which each part is to be made. Numerous materials are available to today's designers. The function of the product, its appearance, the cost of the material, and the cost of fabrication are important in making a selection. A careful evaluation of the properties of a. material must be made prior to any calculations. 仔细精确的计算是必要的,以确保设计的有效性。在任何失败的情况下,最好知道在最初设计中有有缺陷的部件。计算(图纸尺寸)检查是非常重要的。一个小数点的位置放错,就可以导致一个本可以完成的项目失败。设计工作的各个方面都应该检查和复查。 Careful calculations are necessary to ensure the validity of a design. In case of any part failures, it is desirable to know what was done in originally designing the defective components. The checking of calculations (and drawing dimensions) is of utmost importance. The misplacement of one decimal point can ruin an otherwise acceptable project. All aspects of design work should be checked and rechecked. 计算机是一种工具,它能够帮助机械设计师减轻繁琐的计算,并对现有数据提供进一步的分析。互动系统基于计算机的能力,已经使计算机辅助设计(CAD)和计算机辅助制造(CAM)成为了可能。心理学家经常谈论如何使人们适应他们所操作的机器。设计人员的基本职责是努力使机器来适应人们。这并不是一项容易的工作,因为实际上并不存在着一个对所有人来说都是最优的操作范围和操作

机械类英语论文及翻译翻译

High-speed milling High-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 machining High-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 productivity High-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 quality High-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.

外文翻译英文

A Distributed Approach for Track Occupancy Detection Abstract This paper investigates the problem of track occupancy detection in distributed settings. Track occupancy detection determines which tracks are occupied in a railway system. For each track, the Neyman–Pearson structure is applied to reach the local decision. Globally, it is a multiple hypotheses testing problem. The Bayesian approach is employed to minimize the probability of the global decision error. Based on the prior probabilities of multiple hypotheses and the approximation of the prior probabilities of multiple hypotheses and the approximationofthereceiving operation characteristic curve of the local detector, a person-by-person optimization method is implemented to obtain the fusion rule and the local strategies off line. The results are illustrated through an example constructed from in situ devices. Key Words:Track occupancy detection,Neyman–Pearson, Generalized likelihood ratio test, Bayesian approach,Distributed detection 1Introduction With respect to the majority of railway systems in China, a quasi-moving block method is employed to specify the safe zone of a train. A key piece of knowledge to be determined is the set of track segments that are occupied, i.e., track occupancy detection. Then the speed restriction curves for the following trains are calculated accordingly. When there are misdetections, collisions may happen; additionally, false alarms may lead to declines of line capacity. Track occupancy detection is achieved by a set of track circuits. The track circuit is a crucial device mainly composed of a transmitter–receiver pair and a track segment. The measurement is the receiving signal at the end of the track. For each segment, a decision is made locally and individually, which leads to frequent ambiguities on which tracks are occupied for the whole line. It means that the false alarm rate of the line increases greatly. Besides, for the next generation of railway systems, a moving block method is adopted. Such a method requires the exact position and velocity of the train. However, those data are not provided in the current detection mechanism.

机械图纸中英文翻译汇总

近几年,我厂和英国、西班牙的几个公司有业务往来,外商传真发来的图纸都是英文标注,平时阅看有一定的困难。下面把我们积累的几点看英文图纸的经验与同行们交流。 1标题栏 英文工程图纸的右下边是标题栏(相当于我们的标题栏和部分技术要求),其中有图纸名称(TILE)、设计者(DRAWN)、审查者(CHECKED)、材料(MATERIAL)、日期(DATE)、比例(SCALE)、热处理(HEAT TREATMENT)和其它一些要求,如: 1)TOLERANCES UNLESS OTHERWISE SPECIFIAL 未注公差。 2)DIMS IN mm UNLESS STATED 如不做特殊要求以毫米为单位。 3)ANGULAR TOLERANCE±1°角度公差±1°。 4)DIMS TOLERANCE±0.1未注尺寸公差±0.1。 5)SURFACE FINISH 3.2 UNLESS STATED未注粗糙度3.2。 2常见尺寸的标注及要求 2.1孔(HOLE)如: (1)毛坯孔:3"DIAO+1CORE 芯子3"0+1; (2)加工孔:1"DIA1"; (3)锪孔:锪孔(注C'BORE=COUNTER BORE锪底面孔); (4)铰孔:1"/4 DIA REAM铰孔1"/4; (5)螺纹孔的标注一般要表示出螺纹的直径,每英寸牙数(螺矩)、螺纹种类、精度等级、钻深、攻深,方向等。如: 例1.6 HOLES EQUI-SPACED ON 5"DIA (6孔均布在5圆周上(EQUI-SPACED=EQUALLY SPACED均布) DRILL 1"DIATHRO' 钻1"通孔(THRO'=THROUGH通) C/SINK22×6DEEP 沉孔22×6 例2.TAP7"/8-14UNF-3BTHRO' 攻统一标准细牙螺纹,每英寸14牙,精度等级3B级 (注UNF=UNIFIED FINE THREAD美国标准细牙螺纹) 1"DRILL 1"/4-20 UNC-3 THD7"/8 DEEP 4HOLES NOT BREAK THRO钻 1"孔,攻1"/4美国粗牙螺纹,每英寸20牙,攻深7"/8,4孔不准钻通(UNC=UCIFIED COARSE THREAD 美国标准粗牙螺纹)

机械工程专业英语 翻译

2、应力和应变 在任何工程结构中独立的部件或构件将承受来自于部件的使用状况或工作的外部环境的外力作用。如果组件就处于平衡状态,由此而来的各种外力将会为零,但尽管如此,它们共同作用部件的载荷易于使部件变形同时在材料里面产生相应的内力。 有很多不同负载可以应用于构件的方式。负荷根据相应时间的不同可分为: (a)静态负荷是一种在相对较短的时间内逐步达到平衡的应用载荷。 (b)持续负载是一种在很长一段时间为一个常数的载荷, 例如结构的重量。这种类型的载荷以相同的方式作为一个静态负荷; 然而,对一些材料与温度和压力的条件下,短时间的载荷和长时间的载荷抵抗失效的能力可能是不同的。 (c)冲击载荷是一种快速载荷(一种能量载荷)。振动通常导致一个冲击载荷, 一般平衡是不能建立的直到通过自然的阻尼力的作用使振动停止的时候。 (d)重复载荷是一种被应用和去除千万次的载荷。 (e)疲劳载荷或交变载荷是一种大小和设计随时间不断变化的载荷。 上面已经提到,作用于物体的外力与在材料里面产生的相应内力平衡。因此,如果一个杆受到一个均匀的拉伸和压缩,也就是说, 一个力,均匀分布于一截面,那么产生的内力也均匀分布并且可以说杆是受到一个均匀的正常应力,应力被定义为 应力==负载 P /压力 A, 因此根据载荷的性质应力是可以压缩或拉伸的,并被度量为牛顿每平方米或它的倍数。 如果一个杆受到轴向载荷,即是应力,那么杆的长度会改变。如果杆的初始长度L和改变量△L已知,产生的应力定义如下: 应力==改变长△L /初始长 L 因此应力是一个测量材料变形和无量纲的物理量 ,即它没有单位;它只是两个相同单位的物理量的比值。 一般来说,在实践中,在荷载作用下材料的延伸是非常小的, 测量的应力以*10-6的形式是方便的, 即微应变, 使用的符号也相应成为ue。 从某种意义上说,拉伸应力与应变被认为是正的。压缩应力与应变被认为是负的。因此负应力使长度减小。 当负载移除时,如果材料回复到初始的,无负载时的尺寸时,我们就说它是具有弹性的。一特定形式的适用于大范围的工程材料至少工程材料受载荷的大部分的弹性, 产生正比于负载的变形。由于载荷正比于载荷所产生的压力并且变形正比于应变, 这也说明,当材料是弹性的时候, 应力与应变成正比。因此胡克定律陈述, 应力正比于应变。 这定律服从于大部分铁合金在特定的范围内, 甚至以其合理的准确性可以假定适用于其他工程材料比如混凝土,木材,非铁合金。 当一个材料是弹性的时候,当载荷消除之后,任何负载所产生的变形可以完全恢复,没有永久的变形。

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