机械工程专业英语文本施平05
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机械专业类英语文章阅读篇一:机械专业英语作文1Mechanical engineeringEngineering Science in life are widely used, especially in mechanical engineering in the application of life is almost throughout life in all its aspects, to automobiles, aircraft, small electric fans, umbrella, all of these and related machinery. The project includes many subjects, but the mechanical engineering is one of the most important subjects, not only because of our life and itis closely related to, but with the progress of the times, people have to rely on mechanical engineering products, in automation today, machine instead of many this is the part of the human labor, improve the efficiency and save time.As a result of mechanical engineering in every aspect of life, therefore, as an engineer, be faced with a great many challenges, in addition to a solid with knowledge, but also keep pace with the times, familiar with the machinery and related software, can be very good use of software, and as a an engineer, we should try our best to design and produce and closely related to the life of the machine, and can in life play a real role, also have only such, we address and remission now social needs, therefore, the mechanical engineering in the future social development, will play the important role, especially China s case, the industry also is not very developed, machinery can be greater development space.Before the industrial revolution, machinery is mostly wood structure, wood made by hand by. The development of social economy,the demand for mechanical products. The bulk of the production increasing and precision processing technology progress, promote the mass production method ( interchangeability of parts production, professional division of labor and cooperation, water processinglines and assembly lines ) formation. Study of mechanical products in the manufacturing process, especially when used in the pollution of the environment and natural resources excessive consumption problems and their treatment measures. This is a modern mechanical engineering is an especially important task to grow with each passing day, andits importance.Application of mechanical products. This includes selection, ordering, acceptance, installation, adjustment, operation, maintenance, repair and transformation of the industrial use of machinery and complete sets of machinery and equipment, to ensurethat the mechanical products in the long-term use of reliability and economy.As a student, we are now the most important to learn professional knowledge, only in this way, can we later life and learning, to doits part.机械工程工程科学在生活中应用广泛,特别是机械工程在生活中的应用几乎就是遍布了生活中的各个方面,大到汽车、飞机,小到电风扇、雨伞,这些都和机械有关。
Lesson 1 力学的基本概念1、词汇:statics [stætiks] 静力学;dynamics动力学;constraint约束;magnetic [mæɡ'netik]有磁性的;external [eks'tə:nl] 外面的, 外部的;meshing啮合;follower从动件;magnitude ['mæɡnitju:d] 大小;intensity强度,应力;non-coincident [kəu'insidənt]不重合;parallel ['pærəlel]平行;intuitive 直观的;substance物质;proportional [prə'pɔ:ʃənəl]比例的;resist抵抗,对抗;celestial [si'lestjəl]天空的;product乘积;particle质点;elastic [i'læstik]弹性;deformed变形的;strain拉力;uniform全都相同的;velocity[vi'lɔsiti]速度;scalar['skeilə]标量;vector['vektə]矢量;displacement代替;momentum [məu'mentəm]动量;2、词组make up of由……组成;if not要不,不然;even through即使,纵然;Lesson 2 力和力的作用效果1、词汇:machine 机器;mechanism机构;movable活动的;given 规定的,给定的,已知的;perform执行;application 施用;produce引起,导致;stress压力;applied施加的;individual单独的;muscular ['mʌskjulə]]力臂;gravity[ɡrævti]重力;stretch伸展,拉紧,延伸;tensile[tensail]拉力;tension张力,拉力;squeeze挤;compressive 有压力的,压缩的;torsional扭转的;torque转矩;twist扭,转动;molecule [m likju:l]分子的;slide滑动; 滑行;slip滑,溜;one another 互相;shear剪切;independently独立地,自立地;beam梁;compress压;revolve (使)旋转;exert [iɡ'zə:t]用力,尽力,运用,发挥,施加;principle原则, 原理,准则,规范;spin使…旋转;screw螺丝钉;thread螺纹;2、词组a number of 许多;deal with 涉及,处理;result from由什么引起;prevent from阻止,防止;tends to 朝某个方向;in combination结合;fly apart飞散;3、译文:任何机器或机构的研究表明每一种机构都是由许多可动的零件组成。
《机械工程专业英语》课程教学大纲一、课程的基本情况课程中文名称: 机械工程专业英语课程英文名称: ENGLISH IN MECHANICAL ENGINEERING课程代码:0304030课程类别:必修课程学分:2分课程学时:18授课对象:机电(电专)学生前导课程:机械设计、机械原理、大学英语二、教学目的机械工程专业英语是机械工程及自动化专业的一门指选专业课程。
其教学目的是使学生完成大学英语的教学后及时转入专业英语阅读,巩固已经掌握的基本词汇和语法知识,扩大专业词汇,掌握科技文章的语法结构,提高英语应用能力,特别是阅读、翻译本专业英语文献的能力。
达到以英语为工具,获取专业所需要的信息。
三、教学基本要求第1课力学基本概念Lesson 1 Basic Concepts in Mechanics重点:力学的基本词汇和力学知识第3课力和力矩Lesson 3 Forces and Moments重点:力学的基本词汇和基本知识第5课轴和联轴器Lesson 5 Shafts and Couplings重点:轴的基本词汇和基本知识第13课机构Lesson 13 Mechanism重点:机构的基本词汇和基本知识第17课机械设计基础Lesson 17 Fundamentals of Mechanical Design重点:机械设计的基本词汇和基本知识第45课计算机与制造业Lesson 45 The computer and Manufacturing重点:计算机与制造业的基本词汇和基本知识翻译技巧:词类转换第49课数字控制Lesson 49 Numerical Control重点:数字控制的基本词汇和基本知识翻译技巧:成分转换第53课工业机器人Lesson53 Industrial Robots重点:工业机器人的基本词汇和基本知识翻译技巧:掌握相应专业词汇第55课机器人系统的组成部分Lesson 55 Components of a Robot System重点:机器人系统的基本词汇和基本知识翻译技巧成分转换第57课工程师在机械制造业中的作用Lesson 57 The Roles of Engineers in Manufacturing重点:机械制造的基本词汇和基本知识翻译技巧状语从句的译法第59课信息时代的机械工程Lesson 59 Mechanical Engineering in the Information Age重点:机械工程的基本词汇和基本知识翻译技巧成分分译第61课如何撰写科学论文Lesson 61 How to Write a Scientific Paper重点:科学论文写作的基本词汇和基本知识翻译技巧长句分析四、课程内容与学时分配五、教材与参考书教材:《机械工程专业英语》,施平编,哈工大出版社,2007参考书:《机械工程英语》,陈道礼、刘旺、夏绪辉编,武汉科技大学机械自动化学院六、教学方式和考核方式1、教学方式:以课堂讲授为主,辅以课后作业。
机械工程专业英语原文翻译令狐采学创作2、应力和应变令狐采学在任何工程结构中自力的部件或构件将接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资料里面产生相应的内力。
有很多不合负载可以应用于构件的方法。
负荷根据相应时间的不合可分为:(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)继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法作为一个静态负荷;然而,对一些资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当失效的能力可能是不合的。
(c)冲击载荷是一种快速载荷(一种能量载荷)。
振动通常招致一个冲击载荷, 一般平衡是不克不及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年夜小和设计随时间不竭变更的载荷。
令狐采学创作令狐采学创作上面已经提到,作用于物体的外力与在资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,均匀散布于一截面,那么产生的内力也均匀散布并且可以说杆是受到一个均匀的正常应力,应力被界说为应力==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,并被怀抱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,那么杆的长度会修改。
如果杆的初始长度L和修改量△L已知,产生的应力界说如下:应力==修改长△L /初始长L因此应力是一个丈量资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,在荷载作用下资料的延伸是很是小的, 丈量的应力以*106的形式是便利的,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。
第一课Text:It is known that metals are very important in our life. Metals have the greatest importance for industry. All machines and other engineering[7endVi5niEriN] constructions have metal[5metl] parts; some of them consist only of metal parts.众所周知,金属在我们的生活中是非常重要的,金属对于工业而言是有巨大的重要性,所有机器和其他工程构造都有金属零部件,其中一些还只能由金属组成。
There are two large groups of metals:1) Simple metal- more or less pure chemical elements[5elimEnt]2) Alloys[5AlCi]- materials consisting of a simple metal combined with some other elements.有两大类金属:(1)纯金属——或多或少的金属元素(2)合金——组成纯金属的原料结合其他元素。
About two thirds of all elements found in the earth are metals, but not all metals may be used in industry. Those metals which are used in industry are called engineering metals. The most important engineering metalis iron[5aiEn], which in the form of alloys with carbon[5kB:bEn] and other elements, finds greater use than any other metal. Metals consisting of iron combined with some other elements are known as ferrous[5ferEs] metals; all the other metals are called nonferrous[5nCn5ferEs] metals. The most important nonferrous metal arecopper[5kCpE], aluminum[E5lju:minEm], lead[li:d], zinc[ziNk], tin[tin], but all these metals are used muchless than ferrous metals, because the ferrous metals are much cheaper.在地球上发现的所有元素中,大约三分之二是金属元素,但是并不是所有的金属都能够用于工业上。
Spur GearsGears , defined as toothed members transmitting rotary motion from one shaft to another , are among the oldest devices and inventions of man . In about 2600 B.C. , the Chinese are known to have used a chariot incorporating a complex series of gears . Aristotle , in the fourth century B.C. , wrote of gears as if they were commonplace . In the fifteenth century A.D. , Leonardo da Vinci designed a multitude of devices incorporating many kinds of gears .齿轮,在最古老的设备和发明人中,被定义为通过轮齿将旋转运动从一根轴传递到另一根轴,大约在公元前2600年,中国人就知道用战车组成一系列复杂的齿轮系。
西元前四世纪,亚里士多德记述了齿轮就好像是他们司空见惯的一样。
在十五世纪,达芬奇设计了大量的包含各种各样齿轮的设备。
Among the various means of mechanical power transmission (including primarily gears , belts , and chains ) , gears are generally the most rugged and durable . Their power transmission efficiency is as high as 98 percent . On the other hand , gears are usually more costly than chains and belts . As would be expected , gear manufacturing costs increase sharply with increased precision -- as required for the combination of high speeds and heavy loads , and for low noise levels . ( Standard tolerances for various degrees of manufacturing precision have been established by the AGMA , American Gear Manufacturers Association. )在众多的机械传动方式中(包括齿轮传动,带传动,链传动),一般来说,齿轮是最经久耐用的,它的能量传递效率高达98%。
机械工程英语原文+翻译完整版第一单元Types of Materials材料的类型Materials may be grouped in several ways. Scientists often classify materials by their state: solid, liquid, or gas. They also separate them into organic (once living) and inorganic (never living) materials.材料可以按多种方法分类。
科学家常根据状态将材料分为:固体、液体或气体。
他们也把材料分为有机材料(曾经有生命的)和无机材料(从未有生命的)。
For industrial purposes, materials are divided into engineering materials or nonengineering materials. Engineering materials are those used in manufacture and become parts of products.就工业效用而言,材料被分为工程材料和非工程材料。
那些用于加工制造并成为产品组成部分的就是工程材料。
Nonengineering materials are the chemicals, fuels, lubricants, and other materials used in the manufacturing process, which do not become part of the product.非工程材料则是化学品、燃料、润滑剂以及其它用于加工制造过程但不成为产品组成部分的材料。
Engineering materials may be further subdivided into: ①Metal ②Ceramics ③Composite ④Polymers, etc.工程材料还能进一步细分为:①金属材料②陶瓷材料③复合材料④聚合材料,等等。
第三课Overview of Engineering Mechanics工程力学概述当我们观察我们周围就会发现世界充满“物品”:机器,设备,工具;我们已经设计,建造,并使用的物品;木头,金属,陶瓷和塑料制品。
根据我们使用的经验知道,有些物品比其它物品更好;他们使用寿命较长,费用较低,噪音更低,更好看,或者更方便我们使用。
然而,在理想的情况下,每一件产品都是设计人员工具其对某些“功能要求”的理解而设计出来的,也就是说,在设计过程中,应该回答这样的问题,即“它应该具有哪种确切的功能?”在工程领域,主要功能通常是承受由于重力,惯性力,压力等作用的一些类型的载荷。
从我们居住房屋的梁到飞机机翼,都必须有一个适当的材料,尺寸,在较合理的寿命基础上具有较合理的成本并能可靠地完成其功能的产品结构连接的组合。
在实践中,工程力学方法常被应用在两个完全不同领域:(1) 任何新装置的研发都需要对其结构,尺寸,材料,载荷,耐久性,安全和成本的反复考虑。
(2) 当一个装置(意外地)发生失效后,通常需要进行研究,找出失效的原因,并找出潜在的纠正措施。
最好的设计往往都是不断排除薄弱环节的演变过程。
对许多工程师来说,上述过程既可以令人非常的陶醉又可以使人非常的愉快,更何况(有时)对我们是有利的。
对于任何实际的问题,总是缺乏足够完整和有用的信息。
我们很少准确地知道实际荷载和工作状态,因此,所做的分析工作也很少是精确的。
虽然我们的数学可以准确,全面的分析一般只能近似,而且不同技术水平的人能得到不同的解。
在工程力学研究领域,大多数问题要想得到唯一解就要充分的理想化,但应该清楚,“现实世界”远不非理想化程度,因此为了得到问题的解决方案不得不进行一些理想化假设。
我们要考虑的技术领域通常被称为“静力学”和“材料力学”,“静力学”,指的是研究作用在固定装置上的作用力,“材料力学”指的是施加到结构的力(变形,载荷限制等)的影响。
但是,事实上很多设备都不是静态的,如果与动力学有关的额外负荷被考虑了的话,那么静力学的研究方法完全适用于动态的情况,只要动态力相对静态载荷较小,系统通常被认为是静态的。
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主轴箱headstock卡盘chuck加工中心machining center车刀lathe tool车床lathe钻削镗削bore车削turning磨床grinder基准benchmark钳工locksmith锻forge压模stamping焊weld拉床broaching machine拉孔broaching装配assembling铸造found流体动力学fluid dynamics流体力学fluid mechanics加工machining液压hydraulic pressure切线tangent机电一体化mechanotronics mechanical-electrical integration 气压air pressure pneumatic pressure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随机信号random signal离散信号discrete signal超声传感器ultrasonic sensor集成电路integrate circuit挡板orifice plate残余应力residual stress套筒sleeve扭力torsion冷加工cold machining电动机electromotor汽缸cylinder过盈配合interference fit热加工hotwork摄像头CCD camera倒角rounding chamfer优化设计optimal design工业造型设计industrial moulding design有限元finite element滚齿hobbing插齿gear shaping伺服电机actuating motor铣床milling machine钻床drill machine镗床boring machine步进电机stepper motor丝杠screw rod导轨lead rail组件subassembly可编程序逻辑控制器Programmable Logic Controller PLC 电火花加工electric spark machining电火花线切割加工electrical discharge wire - cutting相图phase diagram热处理heat treatment固态相变solid state phase changes有色金属nonferrous metal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 wheelAssembly line 组装线Layout 布置图Conveyer 流水线物料板Rivet table 拉钉机Rivet gun 拉钉枪Screw driver 起子Pneumatic screw driver 气动起子worktable 工作桌OOBA 开箱检查fit together 组装在一起fasten 锁紧(螺丝)fixture 夹具(治具)pallet 栈板barcode 条码barcode scanner 条码扫描器fuse together 熔合fuse machine热熔机repair修理operator作业员QC品管supervisor 课长ME 制造工程师MT 制造生技cosmetic inspect 外观检查inner parts inspect 内部检查thumb screw 大头螺丝lbs. inch 镑、英寸EMI gasket 导电条front plate 前板rear plate 后板chassis 基座bezel panel 面板power button 电源按键reset button 重置键Hi-pot test of SPS 高源高压测试Voltage switch of SPS 电源电压接拉键sheet metal parts 冲件plastic parts 塑胶件SOP 制造作业程序material check list 物料检查表work cell 工作间trolley 台车carton 纸箱sub-line 支线left fork 叉车personnel resource department 人力资源部production department生产部门planning department企划部QC Section品管科stamping factory冲压厂painting factory烤漆厂molding factory成型厂common equipment常用设备uncoiler and straightener整平机punching machine 冲床robot机械手hydraulic machine油压机lathe车床planer |plein|刨床miller铣床grinder磨床linear cutting线切割electrical sparkle电火花welder电焊机staker=reviting machine铆合机position职务president董事长general manager总经理special assistant manager特助factory director厂长department director部长deputy manager | =vice manager副理section supervisor课长deputy section supervisor =vice section superisor副课长group leader/supervisor组长line supervisor线长assistant manager助理to move, to carry, to handle搬运be put in storage入库pack packing包装to apply oil擦油to file burr 锉毛刺final inspection终检to connect material接料to reverse material 翻料wet station沾湿台Tiana天那水cleaning cloth抹布to load material上料to unload material卸料to return material/stock to退料scraped |\\'skr?pid|报废scrape ..v.刮;削deficient purchase来料不良manufacture procedure制程deficient manufacturing procedure制程不良oxidation |\\' ksi\\'dei?n|氧化scratch刮伤dents压痕defective upsiding down抽芽不良defective to staking铆合不良embedded lump镶块feeding is not in place送料不到位stamping-missing漏冲production capacity生产力education and training教育与训练proposal improvement提案改善spare parts=buffer备件forklift叉车trailer=long vehicle拖板车compound die合模die locker锁模器pressure plate=plate pinch压板bolt螺栓administration/general affairs dept总务部automatic screwdriver电动启子thickness gauge厚薄规gauge(or jig)治具power wire电源线buzzle蜂鸣器defective product label不良标签identifying sheet list标示单location地点present members出席人员subject主题conclusion结论decision items决议事项responsible department负责单位pre-fixed finishing date预定完成日approved by / checked by / prepared by核准/审核/承办PCE assembly production schedule sheet PCE组装厂生产排配表model机锺work order工令revision版次remark备注production control confirmation生产确认checked by初审approved by核准department部门stock age analysis sheet 库存货龄分析表on-hand inventory现有库存available material良品可使用obsolete material良品已呆滞to be inspected or reworked 待验或重工total合计cause description原因说明part number/ P/N 料号type形态item/group/class类别quality品质prepared by制表notes说明year-end physical inventory difference analysis sheet 年终盘点差异分析表physical inventory盘点数量physical count quantity帐面数量difference quantity差异量cause analysis原因分析raw materials原料materials物料finished product成品semi-finished product半成品packing materials包材good product/accepted goods/ accepted parts/good parts良品defective product/non-good parts不良品disposed goods处理品warehouse/hub仓库on way location在途仓oversea location海外仓spare parts physical inventory list备品盘点清单spare molds location模具备品仓skid/pallet栈板tox machine自铆机wire EDM线割EDM放电机coil stock卷料sheet stock片料tolerance工差score=groove压线cam block滑块pilot导正筒trim剪外边pierce剪内边drag form压锻差pocket for the punch head挂钩槽slug hole废料孔feature die公母模expansion dwg展开图radius半径shim(wedge)楔子torch-flame cut火焰切割set screw止付螺丝form block折刀stop pin定位销round pierce punch=die button圆冲子shape punch=die insert异形子stock locater block定位块under cut=scrap chopper清角active plate活动板baffle plate挡块cover plate盖板male die公模female die母模groove punch压线冲子air-cushion eject-rod气垫顶杆spring-box eject-plate弹簧箱顶板bushing block衬套insert 入块club car高尔夫球车capability能力parameter参数factor系数phosphate皮膜化成viscosity涂料粘度alkalidipping脱脂main manifold主集流脉bezel斜视规blanking穿落模dejecting顶固模demagnetization去磁;消磁high-speed transmission高速传递heat dissipation热传rack上料degrease脱脂rinse水洗alkaline etch龄咬desmut剥黑膜D.I. rinse纯水次Chromate铬酸处理Anodize阳性处理seal封孔revision版次part number/P/N料号good products良品scraped products报放心品defective products不良品finished products成品disposed products处理品barcode条码flow chart流程表单assembly组装stamping冲压molding成型spare parts=buffer备品coordinate座标dismantle the die折模auxiliary fuction辅助功能poly-line多义线heater band 加热片thermocouple热电偶sand blasting喷沙grit 砂砾derusting machine除锈机degate打浇口dryer烘干机induction感应induction light感应光response=reaction=interaction感应ram连杆edge finder巡边器concave凸convex凹short射料不足nick缺口speck瑕??shine亮班splay 银纹gas mark焦痕delamination起鳞cold slug冷块blush 导色gouge沟槽;凿槽satin texture段面咬花witness line证示线patent专利grit沙砾granule=peuet=grain细粒grit maker抽粒机cushion缓冲magnalium镁铝合金magnesium镁金metal plate钣金lathe车mill锉plane刨grind磨drill铝boring镗blinster气泡fillet镶;嵌边through-hole form通孔形式voller pin formality滚针形式cam driver铡楔shank摸柄crank shaft曲柄轴augular offset角度偏差velocity速度production tempo生产进度现状torque扭矩spline=the multiple keys花键quenching淬火tempering回火annealing退火carbonization碳化tungsten high speed steel钨高速的moly high speed steel钼高速的organic solvent有机溶剂bracket小磁导liaison联络单volatile挥发性resistance电阻ion离子titrator滴定仪beacon警示灯coolant冷却液crusher破碎机阿基米德蜗杆Archimedes worm安全系数safety factor; factor of safety安全载荷safe load凹面、凹度concavity扳手wrench板簧flat leaf spring半圆键woodruff key变形deformation摆杆oscillating bar摆动从动件oscillating follower摆动从动件凸轮机构cam with oscillating follower 摆动导杆机构oscillating guide-bar mechanism 摆线齿轮cycloidal gear摆线齿形cycloidal tooth profile摆线运动规律cycloidal motion摆线针轮cycloidal-pin wheel包角angle of contact保持架cage背对背安装back-to-back arrangement背锥back cone ;normal cone背锥角back angle背锥距back cone distance比例尺scale比热容specific heat capacity闭式链closed kinematic chain闭链机构closed chain mechanism臂部arm变频器frequency converters变频调速frequency control of motor speed变速speed change变速齿轮change gear change wheel变位齿轮modified gear变位系数modification coefficient标准齿轮standard gear标准直齿轮standard spur gear表面质量系数superficial mass factor表面传热系数surface coefficient of heat transfer表面粗糙度surface roughness并联式组合combination in parallel并联机构parallel mechanism并联组合机构parallel combined mechanism并行工程concurrent engineering并行设计concurred design, CD不平衡相位phase angle of unbalance不平衡imbalance (or unbalance)不平衡量amount of unbalance不完全齿轮机构intermittent gearing波发生器wave generator波数number of waves补偿compensation参数化设计parameterization design, PD残余应力residual stress操纵及控制装置operation control device槽轮Geneva wheel槽轮机构Geneva mechanism ;Maltese cross槽数Geneva numerate槽凸轮groove cam侧隙backlash差动轮系differential gear train差动螺旋机构differential screw mechanism差速器differential常用机构conventional mechanism; mechanism in common use 车床lathe承载量系数bearing capacity factor承载能力bearing capacity成对安装paired mounting尺寸系列dimension series齿槽tooth space齿槽宽spacewidth齿侧间隙backlash齿顶高addendum齿顶圆addendum circle齿根高dedendum齿根圆dedendum circle齿厚tooth thickness齿距circular pitch齿宽face width齿廓tooth profile齿廓曲线tooth curve齿轮gear齿轮变速箱speed-changing gear boxes齿轮齿条机构pinion and rack齿轮插刀pinion cutter; pinion-shaped shaper cutter 齿轮滚刀hob ,hobbing cutter齿轮机构gear齿轮轮坯blank齿轮传动系pinion unit齿轮联轴器gear coupling齿条传动rack gear齿数tooth number齿数比gear ratio齿条rack齿条插刀rack cutter; rack-shaped shaper cutter齿形链、无声链silent chain齿形系数form factor齿式棘轮机构tooth ratchet mechanism插齿机gear shaper重合点coincident points重合度contact ratio冲床punch传动比transmission ratio, speed ratio传动装置gearing; transmission gear传动系统driven system传动角transmission angle传动轴transmission shaft串联式组合combination in series串联式组合机构series combined mechanism串级调速cascade speed control创新innovation creation创新设计creation design垂直载荷、法向载荷normal load唇形橡胶密封lip rubber seal磁流体轴承magnetic fluid bearing从动带轮driven pulley从动件driven link, follower从动件平底宽度width of flat-face从动件停歇follower dwell从动件运动规律follower motion从动轮driven gear粗线bold line粗牙螺纹coarse thread大齿轮gear wheel打包机packer打滑slipping带传动belt driving带轮belt pulley带式制动器band brake单列轴承single row bearing单向推力轴承single-direction thrust bearing单万向联轴节single universal joint单位矢量unit vector当量齿轮equivalent spur gear; virtual gear当量齿数equivalent teeth number; virtual number of teeth当量摩擦系数equivalent coefficient of friction当量载荷equivalent load刀具cutter导数derivative倒角chamfer导热性conduction of heat导程lead导程角lead angle等加等减速运动规律parabolic motion; constant acceleration and deceleration motion等速运动规律uniform motion; constant velocity motion等径凸轮conjugate yoke radial cam等宽凸轮constant-breadth cam等效构件equivalent link等效力equivalent force等效力矩equivalent moment of force等效量equivalent等效质量equivalent mass等效转动惯量equivalent moment of inertia等效动力学模型dynamically equivalent model底座chassis低副lower pair点划线chain dotted line(疲劳)点蚀pitting垫圈gasket垫片密封gasket seal碟形弹簧belleville spring顶隙bottom clearance定轴轮系ordinary gear train; gear train with fixed axes动力学dynamics动密封kinematical seal动能dynamic energy动力粘度dynamic viscosity动力润滑dynamic lubrication动平衡dynamic balance动平衡机dynamic balancing machine动态特性dynamic characteristics动态分析设计dynamic analysis design动压力dynamic reaction动载荷dynamic load端面transverse plane端面参数transverse parameters端面齿距transverse circular pitch端面齿廓transverse tooth profile端面重合度transverse contact ratio端面模数transverse module端面压力角transverse pressure angle锻造forge对称循环应力symmetry circulating stress对心滚子从动件radial (or in-line ) roller follower对心直动从动件radial (or in-line ) translating follower对心移动从动件radial reciprocating follower对心曲柄滑块机构in-line slider-crank (or crank-slider) mechanism 多列轴承multi-row bearing多楔带poly V-belt多项式运动规律polynomial motion多质量转子rotor with several masses惰轮idle gear额定寿命rating life额定载荷load ratingII 级杆组dyad发生线generating line发生面generating plane法面normal plane法面参数normal parameters法面齿距normal circular pitch法面模数normal module法面压力角normal pressure angle法向齿距normal pitch法向齿廓normal tooth profile法向直廓蜗杆straight sided normal worm法向力normal force反馈式组合feedback combining反向运动学inverse ( or backward) kinematics反转法kinematic inversion反正切Arctan范成法generating cutting仿形法form cutting方案设计、概念设计concept design, CD防振装置shockproof device飞轮flywheel飞轮矩moment of flywheel非标准齿轮nonstandard gear非接触式密封non-contact seal非周期性速度波动aperiodic speed fluctuation非圆齿轮non-circular gear粉末合金powder metallurgy分度线reference line; standard pitch line分度圆reference circle; standard (cutting) pitch circle 分度圆柱导程角lead angle at reference cylinder分度圆柱螺旋角helix angle at reference cylinder分母denominator分子numerator分度圆锥reference cone; standard pitch cone分析法analytical method封闭差动轮系planetary differential复合铰链compound hinge复合式组合compound combining复合轮系compound (or combined) gear train复合平带compound flat belt复合应力combined stress复式螺旋机构Compound screw mechanism复杂机构complex mechanism杆组Assur group干涉interference刚度系数stiffness coefficient刚轮rigid circular spline钢丝软轴wire soft shaft刚体导引机构body guidance mechanism刚性冲击rigid impulse (shock)刚性转子rigid rotor刚性轴承rigid bearing刚性联轴器rigid coupling高度系列height series高速带high speed belt高副higher pair格拉晓夫定理Grashoff`s law根切undercutting公称直径nominal diameter高度系列height series功work工况系数application factor工艺设计technological design工作循环图working cycle diagram工作机构operation mechanism工作载荷external loads工作空间working space工作应力working stress工作阻力effective resistance工作阻力矩effective resistance moment公法线common normal line公共约束general constraint公制齿轮metric gears功率power功能分析设计function analyses design共轭齿廓conjugate profiles共轭凸轮conjugate cam构件link鼓风机blower固定构件fixed link; frame固体润滑剂solid lubricant关节型操作器jointed manipulator惯性力inertia force惯性力矩moment of inertia ,shaking moment 惯性力平衡balance of shaking force惯性力完全平衡full balance of shaking force惯性力部分平衡partial balance of shaking force 惯性主矩resultant moment of inertia惯性主失resultant vector of inertia冠轮crown gear广义机构generation mechanism广义坐标generalized coordinate轨迹生成path generation轨迹发生器path generator滚刀hob滚道raceway滚动体rolling element滚动轴承rolling bearing滚动轴承代号rolling bearing identification code 滚针needle roller滚针轴承needle roller bearing滚子roller滚子轴承roller bearing滚子半径radius of roller滚子从动件roller follower滚子链roller chain滚子链联轴器double roller chain coupling滚珠丝杆ball screw滚柱式单向超越离合器roller clutch过度切割undercutting函数发生器function generator函数生成function generation含油轴承oil bearing耗油量oil consumption耗油量系数oil consumption factor赫兹公式H. Hertz equation合成弯矩resultant bending moment合力resultant force合力矩resultant moment of force黑箱black box横坐标abscissa互换性齿轮interchangeable gears花键spline滑键、导键feather key滑动轴承sliding bearing滑动率sliding ratio滑块slider环面蜗杆toroid helicoids worm环形弹簧annular spring缓冲装置shocks; shock-absorber灰铸铁grey cast iron回程return回转体平衡balance of rotors混合轮系compound gear train积分integrate机电一体化系统设计mechanical-electrical integration system design 机构mechanism机构分析analysis of mechanism机构平衡balance of mechanism机构学mechanism机构运动设计kinematic design of mechanism机构运动简图kinematic sketch of mechanism机构综合synthesis of mechanism机构组成constitution of mechanism机架frame, fixed link机架变换kinematic inversion机器machine机器人robot机器人操作器manipulator机器人学robotics技术过程technique process技术经济评价technical and economic evaluation技术系统technique system机械machinery机械创新设计mechanical creation design, MCD机械系统设计mechanical system design, MSD机械动力分析dynamic analysis of machinery机械动力设计dynamic design of machinery机械动力学dynamics of machinery机械的现代设计modern machine design机械系统mechanical system机械利益mechanical advantage机械平衡balance of machinery机械手manipulator机械设计machine design; mechanical design机械特性mechanical behavior机械调速mechanical speed governors机械效率mechanical efficiency机械原理theory of machines and mechanisms机械运转不均匀系数coefficient of speed fluctuation机械无级变速mechanical stepless speed changes基础机构fundamental mechanism基本额定寿命basic rating life基于实例设计case-based design,CBD基圆base circle基圆半径radius of base circle基圆齿距base pitch基圆压力角pressure angle of base circle基圆柱base cylinder基圆锥base cone急回机构quick-return mechanism急回特性quick-return characteristics急回系数advance-to return-time ratio急回运动quick-return motion棘轮ratchet棘轮机构ratchet mechanism棘爪pawl极限位置extreme (or limiting) position极位夹角crank angle between extreme (or limiting) positions计算机辅助设计computer aided design, CAD计算机辅助制造computer aided manufacturing, CAM计算机集成制造系统computer integrated manufacturing system, CIMS 计算力矩factored moment; calculation moment计算弯矩calculated bending moment加权系数weighting efficient加速度acceleration加速度分析acceleration analysis加速度曲线acceleration diagram尖点pointing; cusp尖底从动件knife-edge follower间隙backlash间歇运动机构intermittent motion mechanism 减速比reduction ratio减速齿轮、减速装置reduction gear减速器speed reducer减摩性anti-friction quality渐开螺旋面involute helicoid渐开线involute渐开线齿廓involute profile渐开线齿轮involute gear渐开线发生线generating line of involute渐开线方程involute equation渐开线函数involute function渐开线蜗杆involute worm渐开线压力角pressure angle of involute渐开线花键involute spline简谐运动simple harmonic motion键key键槽keyway交变应力repeated stress交变载荷repeated fluctuating load交叉带传动cross-belt drive交错轴斜齿轮crossed helical gears胶合scoring角加速度angular acceleration角速度angular velocity角速比angular velocity ratio角接触球轴承angular contact ball bearing角接触推力轴承angular contact thrust bearing 角接触向心轴承angular contact radial bearing 角接触轴承angular contact bearing铰链、枢纽hinge校正平面correcting plane接触应力contact stress接触式密封contact seal阶梯轴multi-diameter shaft结构structure结构设计structural design截面section节点pitch point节距circular pitch; pitch of teeth节线pitch line节圆pitch circle节圆齿厚thickness on pitch circle节圆直径pitch diameter节圆锥pitch cone节圆锥角pitch cone angle解析设计analytical design紧边tight-side紧固件fastener径节diametral pitch径向radial direction径向当量动载荷dynamic equivalent radial load径向当量静载荷static equivalent radial load径向基本额定动载荷basic dynamic radial load rating 径向基本额定静载荷basic static radial load tating径向接触轴承radial contact bearing径向平面radial plane径向游隙radial internal clearance径向载荷radial load径向载荷系数radial load factor径向间隙clearance静力static force静平衡static balance静载荷static load静密封static seal局部自由度passive degree of freedom矩阵matrix矩形螺纹square threaded form锯齿形螺纹buttress thread form矩形牙嵌式离合器square-jaw positive-contact clutch 绝对尺寸系数absolute dimensional factor绝对运动absolute motion绝对速度absolute velocity均衡装置load balancing mechanism抗压强度compression strength开口传动open-belt drive开式链open kinematic chain开链机构open chain mechanism可靠度degree of reliability可靠性reliability可靠性设计reliability design, RD空气弹簧air spring空间机构spatial mechanism空间连杆机构spatial linkage空间凸轮机构spatial cam空间运动副spatial kinematic pair空间运动链spatial kinematic chain空转idle宽度系列width series框图block diagram雷诺方程Reynolds‘s equation离心力centrifugal force离心应力centrifugal stress离合器clutch离心密封centrifugal seal理论廓线pitch curve理论啮合线theoretical line of action隶属度membership力force力多边形force polygon力封闭型凸轮机构force-drive (or force-closed) cam mechanism 力矩moment力平衡equilibrium力偶couple力偶矩moment of couple连杆connecting rod, coupler连杆机构linkage连杆曲线coupler-curve连心线line of centers链chain链传动装置chain gearing链轮sprocket sprocket-wheel sprocket gear chain wheel联组V 带tight-up V belt联轴器coupling shaft coupling两维凸轮two-dimensional cam临界转速critical speed六杆机构six-bar linkage龙门刨床double Haas planer轮坯blank轮系gear train螺杆screw螺距thread pitch螺母screw nut螺旋锥齿轮helical bevel gear螺钉screws螺栓bolts螺纹导程lead螺纹效率screw efficiency螺旋传动power screw螺旋密封spiral seal螺纹thread (of a screw)螺旋副helical pair螺旋机构screw mechanism螺旋角helix angle螺旋线helix ,helical line绿色设计green design design for environment马耳他机构Geneva wheel Geneva gear马耳他十字Maltese cross脉动无级变速pulsating stepless speed changes脉动循环应力fluctuating circulating stress脉动载荷fluctuating load铆钉rivet迷宫密封labyrinth seal密封seal密封带seal belt密封胶seal gum密封元件potted component密封装置sealing arrangement面对面安装face-to-face arrangement面向产品生命周期设计design for product`s life cycle, DPLC 名义应力、公称应力nominal stress模块化设计modular design, MD模块式传动系统modular system模幅箱morphology box模糊集fuzzy set模糊评价fuzzy evaluation模数module摩擦friction摩擦角friction angle摩擦力friction force摩擦学设计tribology design, TD摩擦阻力frictional resistance摩擦力矩friction moment摩擦系数coefficient of friction摩擦圆friction circle磨损abrasion wear; scratching末端执行器end-effector目标函数objective function耐腐蚀性corrosion resistance耐磨性wear resistance挠性机构mechanism with flexible elements挠性转子flexible rotor内齿轮internal gear内齿圈ring gear内力internal force内圈inner ring能量energy能量指示图viscosity逆时针counterclockwise (or anticlockwise)啮出engaging-out啮合engagement, mesh, gearing啮合点contact points啮合角working pressure angle啮合线line of action啮合线长度length of line of action啮入engaging-in牛头刨床shaper凝固点freezing point; solidifying point扭转应力torsion stress扭矩moment of torque扭簧helical torsion spring诺模图NomogramO 形密封圈密封O ring seal盘形凸轮disk cam盘形转子disk-like rotor抛物线运动parabolic motion疲劳极限fatigue limit疲劳强度fatigue strength偏置式offset偏( 心) 距offset distance偏心率eccentricity ratio偏心质量eccentric mass偏距圆offset circle偏心盘eccentric偏置滚子从动件offset roller follower偏置尖底从动件offset knife-edge follower偏置曲柄滑块机构offset slider-crank mechanism 拼接matching评价与决策evaluation and decision频率frequency平带flat belt平带传动flat belt driving平底从动件flat-face follower平底宽度face width平分线bisector平均应力average stress平均中径mean screw diameter平均速度average velocity平衡balance平衡机balancing machine平衡品质balancing quality平衡平面correcting plane平衡质量balancing mass平衡重counterweight平衡转速balancing speed平面副planar pair, flat pair平面机构planar mechanism平面运动副planar kinematic pair平面连杆机构planar linkage平面凸轮planar cam平面凸轮机构planar cam mechanism平面轴斜齿轮parallel helical gears普通平键parallel key其他常用机构other mechanism in common use起动阶段starting period启动力矩starting torque气动机构pneumatic mechanism奇异位置singular position起始啮合点initial contact , beginning of contact气体轴承gas bearing千斤顶jack嵌入键sunk key强迫振动forced vibration切齿深度depth of cut曲柄crank曲柄存在条件Grashoff`s law曲柄导杆机构crank shaper (guide-bar) mechanism曲柄滑块机构slider-crank (or crank-slider) mechanism 曲柄摇杆机构crank-rocker mechanism曲齿锥齿轮spiral bevel gear曲率curvature曲率半径radius of curvature曲面从动件curved-shoe follower曲线拼接curve matching曲线运动curvilinear motion曲轴crank shaft驱动力driving force驱动力矩driving moment (torque)。
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。
第 5 次课的教学整体安排 授课时间 第 5 周 周4 第 3、4 节 课时安排 2 授课题目(教学章、节或主题): Working Drawings
教学目的、要求(分掌握、理解、了解三个层次): 掌握本课的专业词汇 学习并掌握专业英语的翻译技巧
教学内容(包括基本内容、重点、难点): Working Drawings Working Drawings; Title Blocks; Parts List; Part Names and Numbers 讲解课文和专业词汇 重点:在翻译的过程中句子表达的准确性和整篇文章的逻辑性。 难点:在科技英语翻译过程中语言的转换技巧
讨论、思考、作业: 作业:复习课文 背诵专业词汇
参考资料(含参考书、文献等):
教学过程设计:复习10分钟,授新课90分钟,安排讨论 分钟,布置作业 分钟 授课类型: 理论课 讨论课 实验课 练习课 其他 教学方式: 讲授 讨论 指导 其他 教学资源: 多媒体 模型 实物 挂图 音像 其他 填写说明:1.每项页面大小可自行添减; 2.教学内容与讨论、思考题、作业部分可合二为一。 5 Working Drawing 生产图纸
Working Drawings are the drawings from which a design is implemented. All principles of orthographic projection(正交投影) and techniques of graphics(制图技术) can be used to communicate the details of a project in working drawings. A detail drawing(零件图) is a working drawing of a single part (or detail) within the set of working drawings. Specifications(技术要求) are the written instructions that accompany working drawings. When the design can be represented on a few sheets, the specifications are usually written on the drawings to consolidate(将…合并…) the information into a single format. All parts must interact with other parts to some degree to yield the desired function from a design(设计期望的功能). Before detail drawings of individual parts are made the designer must thoroughly analyze the working drawing to ensure that the parts fit properly with mating parts, that the correct tolerances are applied, that the contact surfaces are properly finished, and that the proper motion is possible between the parts. Much of the work in preparing working drawings is done by the drafter(绘图员), but the designer, who is usually an engineer, is responsible for their correctness. It is working drawings that bring products and systems into being. Working Drawings are legal contracts(合法的合同构件) that document the design details and specifications as directed by the engineer. Therefore drawings must be as clear, precise, and thorough as possible. Revisions and modifications of a project at the time of production or construction are much more expensive than when done in the preliminary design stages. Poorly executed(制作粗糙的) working drawings result in wasted time and resources and increase implementation costs. To be economically competitive, drawings must be as error-free as possible. The inch is the basic unit of the English system(英制系统), and virtually all shop drawings(车间图纸) in the U.S. are dimensioned in inches. The millimeter is the basic unit of the metric system(公制系统). Metric abbreviation (mm) after the numerals is omitted from dimensions because the SI(国际单位制) symbol near the title block(标题栏) indicates that all units are metric. Some working drawings carry both inch and millimeter dimensions, usually the dimensions in parentheses or brackets(括号) are millimeters. The units may also appear as millimeters first and then be converted and shown in brackets as inches. Converting from one unit to the other results in fractional round-off(四舍五入) errors. And explanation of the primary unit system for each drawing should be noted in the title block. Title Blocks In practice, title blocks usually contain the title or part name, drafter, date, scale(比例尺), company, and sheet number. Other information, such as tolerances, checkers, and materials, also may be given. Any modifications or changes added after the first version to improve the design is shown in the revision blocks(修改栏). Depending on the complexity of the project, a set of working drawings may contain from one to more than a hundred sheets. Therefore, giving the number of each sheet and the total number of sheets in the set on each sheet is important (for example, sheet 2 of 6, sheet 3 of 6, and so on). Parts List The part numbers and part names in the parts list correspond to those given to each part depicted on the working drawings. In addition, the number of identical parts required is given along with the material used to make each part. If all working drawings in a set are the same scale(采用同样的比例), you need to indicate it only once in title block on each set. If several detail drawings on a working drawing are different scales, indicate them on the drawing under each set of views. In this case, indicate, “as shown”(如图所示) in the title block opposite scale. When a drawing is not to scale, place the abbreviation NTS (not to scale) in the title block. Part Names and Numbers(编号) Give each part a name and number, using letters and numbers 1/8-in. (3mm) high. Place part numbers inside circles, called balloons(带圆圈的数字), having diameters approximately four times the height of the numbers. Place part numbers near the views to which they apply, so their association will be clear. On assembly drawings, balloons are especially important because the same parts numbers are used in the parts list. People who check drawings must have special qualifications(专门的资质) that enable them to identify errors and to suggest revisions and modifications that result in a better product at a lower cost. A checker may be chief drafter experienced in drafting and manufacturing processes or the engineer or designer who originated the project. In large companies, personnel in the various shops involved in production review the drawings to ensure that the most efficient production methods are specified for each part. Checkers never check the original drawings; instead, they mark