机械工程英语第二版第二部分完整翻译(叶邦彦、陈统坚主编)教学提纲
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Unit 1 材料的种类(1)材料的分类方法很多。
科学家常用的典型的方法是根据它们的状态分类:固体,液态或气态。
材料也分为有机(可再生)和无机材料(不可再生)。
(2)工业上,材料划分为工程材料或非工程材料。
工程材料用于制造和加工成零件的材料。
非工程材料是化学药品,燃料,润滑剂和其它用于制造又不用来加工成零件的材料。
(3)工程材料可进一步细分为:金属,陶瓷,复合材料,聚合材料,等。
Metals and Metal Alloys 金属和金属合金金属和金属合(4)金属有好的导电好导热性,很多金属有高的强度,高硬度和高的延展性。
象铁,钴,镍这些金属有磁性。
在非常低的温度下,一些金属和金属互化物变成超导体。
(5)合金和纯金属有什么区别?纯金属在元素周期表的特殊区域。
例如用于制造电线的铜和做锅和饮料罐的铝。
合金含有两种以上的金属元素。
改变金属元素的比例可以改变合金的性质。
例如,合金金属的不锈钢,是由铁,镍,和铬组成。
而黄金珠宝含有金镍合金。
(6)为什么要使用金属和合金?很多金属和合金有很高密度并用在要求质量与体积比高的的场合。
一些金属合金,象铝基合金,密度低,用在航空领域可以节省燃料。
很多合金有断裂韧度,可以承受冲击,且耐用。
金属有哪些重要属性?(7)【密度】质量除以体积叫做密度。
很多金属有相对高的密度,特别的,象聚合体。
高密度的材料常是原子量很大,象金或铅。
然而一些金属,像铝或镁密度低,就常常用在要求有金属特性而又要求低质量的场合。
(8)【断裂韧性】断裂韧度用来描述金属抗断裂的能力,特别的,当有裂纹时。
金属通常都有无关紧要的刻痕和凹坑,且有耐冲击性。
足球队员关注这一点当他确信面罩不会被击碎的时候。
(9)【塑形变形】塑性变形表述的是材料在断裂之前弯曲变形的能力。
作为工程师,我们通常设计材料使得能够在正常情况下不变形。
你不会想要一阵强烈的西风就把你的车刮得往东倾斜。
然而,有时,我们可以利用塑性变形。
汽车的承受极限就是在彻底破坏之前靠塑形变形来吸收能量。
•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。
机械工程英语第二版叶邦彦陈统坚主编Casting is a manufacturing process in which molten metal is poured or injected and allowed to solidify in a suitably shaped mold cavity. During or after cooling, the cast part is removed from the mold and then processed for delivery.铸造是一种将熔化的金属倒入或注入合适的铸模腔并且在其中固化的制造工艺。
在冷却期间或冷却后,把铸件从铸模中取出,然后进行交付。
Casting processes and cast-material technologies vary from simple to highly complex. Material and process selection depends on the part’s complexity and function, the product’s quality specifications, and the projected cost level.铸造工艺和铸造材料技术从简单到高度复杂变化很大。
材料和工艺的选择取决于零件的复杂性和功能、产品的质量要求以及成本预算水平。
Castings are parts that are made close to their final dimensions by a casting process. With a history dating back 6,000 years, the various casting processes are in a state of continuous refinement and evolution as technological advances are being made.通过铸造加工,铸件可以做成很接近它们的最终尺寸。
PART 2 Unit 4 机加工与切削加工中心(4)习惯性的加工过程的执行,始于工件的移动从一把加工刀具到另一把加工刀具直至所有的加工完成,这是一种切实可行的制造方法,并具有高度的自动化。
这就是生产流水线的原理。
最常见的是应用于高容量或大批量的生产,生产流水线是由几种加工刀具按一定的次序排列组成的,诸如自动发动机模块这样的工件从一个加工地点到另一个加工地点,并且在每一个加工中心都运用特有的加工方式进行加工,工件会被输送到下一个机器进行下一个加工。
(5)有这样一些产品或加工方法,他们的生产路线是不可行或不经济的,特别是当这些种类的产品在加工时需要迅速转换加工方法。
一个重要的概念,在20 世纪50 年代末期得到发展,那就是机加工中心。
一个机加工中心就是运用计算机控制的刀具在工件的不同表面和不同的方向上进行切削操作的能力,通常说工件是不动的,而切削工具进行旋转,比如铣和钻操作。
(7)工件在加工中心里是被安放在托盘上或模块上,那样可以被移动并且可以进行不同方向的旋转和定位,在进行特殊的切削过程完成后,工件不需要移动到另一台机器进行钻孔,铰孔,攻丝之类的附加加工。
换句话说,工件和机器是被置于工件上的。
(9)加工中心装备了可变程序的自动刀具变换器,依赖于这样的设计多达200 把切削刀具能够被贮存在刀库,刀鼓,刀链(工具库),辅助工具库能够更好的为一些特殊加工中心提供更好的切削道具,这些刀具可以自动的任意选择到达机械主轴的最短路线,刀具交换臂是一个普通的设计机构,他可以旋转来拾取特殊的工具(每一个工具有他自己的刀杆)和他在主轴上的位置。
(14)垂直主轴加工中心或是水平主轴加工中心都是为了适用在工件具有深腔的平面上执行加工工艺,如铸型和模具制造。
一个垂直主轴的加工中心类似于一个垂直主轴铣床。
刀库在图示的左侧并且所有的加工方法和传动机构通过位于右侧的计算机控制托盘进行定位和修改。
(16)水平主轴的加工中心或水平机加工中心是为了适用于高大工件的表面加工的需求。
Unit5 INDUSTRIAL ROBOT工业机械人INTRODUCTION介绍Industrial robots are relatively new electromechanical devices that are beginning to change the appearance of modern industry. Industrial robots are not like the science fiction devices that possesshuman-like abilities and provide companionship with space traveler、Research to enable robots to“see,"hear",“touch",and "listen" has been underway for two decades and is beginning to bearfruit. However,the current technology of industrial robots is such that most robots contain Onlyan arm rather than all the anatomy a human possesses. Current control only allows these devicesto move from point to point in space,performing relatively simple taskes. The Robotics Instituteof America defines a robot as“a reprogram rnable multifunction manipulator designed to move material,parts, tools,or other specialized devices through variable programmed motions for theperformance of a variety of tasks. "' A NC machining center would qualify as a robot if one wereto interpret different types of machining as different functions- Most manufacturing engineers donot consider a NC machining center a robot,even though these machines hive a number of situ-ilarities. The power drive and controllers of both NC machines and robots can be quite similar. Robots, like NC machines can he powered by electrical motors,hydraulic systems,or pnetinlat。
Unit 8 Flexible Manufacturing Systems What Is FMS?FMS是什么?Definitions of FMS, or Flexible Manufacturing Systems, are plentiful and in many respects are dependent on the ultimate user's point of view as to what the FMS consists of and how it will be used. However, the following represent a collection of FMS definitions, some traceable and some not traceable to their originating source.关于柔性制造系统,有很多不同的定义,多数情况下,如何对其定义依赖于其使用者对其组成部分和使用方法的个人看法。
然而,接下来的描述是对FMS 定义的概括,那就是有缘可循和无源可寻的资源。
1) United States Government. A series of automatic machine tools or items of fabrication equipment linked together with an automatic material handling system, a common hierarchical digital pre-programmed computer control, and provision for random fabrication of parts or assemblies that fall within predetermined families.美国政府,一系列自动机床或自动材料处理系统,一个共同的分层预先设定的数字电脑控制,并随机制造的零件或装配,在预定的家庭内的条文,一并与设备制造项目。
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。
•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。
Unit 2 Numerical Control of Production EquipmentUnit 2 生产设备的数字控制Numerical Control (NC) is a form of programmable automation in which the processing equipment is controlled by means of numbers, letters, and other symbols. The numbers, letters, and symbols are coded in an appropriate format to define a program of instructions for a particular work-part or job. 数控是程序控制的自动化,在数字控制系统中,设备通过数字,字母和符号来编码,以一种合适的格式为每一个特定的零件或工件定义一个程序指令集。
When the job changes, the program of instructions is changed. The capability to change the program is what makes NC suitable for low-and medium-volume production. It is much easier to write new programs than to make major alterations of the processing equipment.当工件变化时,程序也变化,改变程序的能力亦适合中小批量生产。
写一个新程序比改变大量生产设备要容易的多。
Basic Components of NC数控基本结构A numerical control system consists of the following three basic components:数控系统由下面三部分组成:• Program of instructions控制程序• Machine control unit机器控制单元• Processing equipment加工设备The general relationship among the three components is illustrated in Fig. 2.1. The program is fed into the control unit, which directs the processing equipment accordingly.三部分的基本关系,由图 2.1 所示。
Unit 9 Computer-Integrated Manufacturing System COMPUTER INTEGRATED MANUFACTURING SYSTEM (1)计算机集成技术CIM DEFINEDComputer-integrated manufacturing or (CIM) is the term used to describe the most modern ap-proach to manufacturing. Although CIM encompasses many of the other advanced manufacturingtechnologies such as computer numerical control (CNC) ,computer-aided design/computer-aidedmanufacturing (CAD/CAM)。
robotics,and just一in-time delivery (J1T),it is more than a newtechnology or a new concept. Computer-integrated manufacturing is actually an entirely new ap-proach to manufacturing a new way of doing business.计算机集成制造(或CIM)是用来描述最现代化的一种制造方法的词汇。
尽管CIM包含了许多其他的先进制造技术,如计算机数字控制(CNC),计算机辅助设计/计算机辅助制造(CAD / CAM),机器人学和及时供货等,但它不仅仅是一种更高层次新技术或新概念。
计算机集成制造实际上是一种全新的制造方法和一种全新的贸易方式。
To understand CIM,it is necessary to begin with a comparison of modern and traditionalmanufacturing. Modern manufacturing encompasses ail of the activities andprocesses necessary to convert raw materials into finished products, deliver them to the market,and support them in thefield'. These activities include the following为了理解CIM,有必要一开始就有一个现代和传统制造业的比较。