机械制造专业英语__课后答案(部分)

机械制造专业英语__课后答案(部分)
机械制造专业英语__课后答案(部分)

专业英语翻译

一stress and strain(应力与应变)

1the fundamental concepts 基本概念

cross section 横截面the internal stresses produced in the bar 杆的内应力continuous distribution of hydrostatic pressure 流体静压力the tensile load 拉伸载荷a uniform dis

tribution over the cross section 在横截面均匀分布arbitrary cross-sectional shape 任意截面形状tensile stresses 拉应力compressive stresses 压应力a normal stress 正应力through the centroid of the cross sectional area 通过横截面形心the uniform stress condition 压力均匀分布the stress distribution at the ends of the bar 杆末端应力分布high localized stresses 高度应力集中an axially loaded bar 轴向载荷杆件a tensile strain 拉应变an elongation or stretching of the material 材料拉伸a compressive strain 压应变the ratio of two lengths 两个长度的比值purely statical and geometrical considerations 从纯静态以及几何角度考虑1.That branch of scientific analysis which motions, times and forces is called mechanics and is made up of two parts, statics and

dynamics. 研究位移、时间和力运动乘力是科学分析法的一个分支,被称作力学,力学由两大部分组成,静力学和动力学。 2.For example, if the force operating on a sleeve bearing becomes too high, it will squeeze out the oil film and cause metal-to-metal contact, overheating and rapid failure of the bearing. 例如:如果止推轴承上的作用力过大的话,会挤出油膜,引起金属和金属之间的相互接触,轴承将过热而迅速失效。 3.Our intuitive concept of force includes such ideas as place of application, direction, and magnitude, and these are called the characteristics of a force. 力的直观概念包括力的作用点、大小、方向,这些被称为力的三要素。 4.All bodies are either elastic or plastic and will be deformed if acted upon by forces. When the deformation of such bodies is small, they are frequently assumed to be rigid, i.e., incapable of deformation, in order to simplify the analysis. 所有的物体既可以是弹性的也可以是塑性的,如果受到力的作用就产生变形。当变形很小的时候它们被假设成刚体,也就是不产生变形。 5.The rigid-body assumption cannot be used in internal stresses and strains due to the applied forces to be analyzed. Thus we consider the body to be capable of deforming. 刚体假设

不能应用于内应力和内应变的分析,所以在实际力的分析时,要考虑物体的形变。 6.If all the forces acting on a particle are balanced, the particle will either remain at rest or will continue to move in a straight line at a uniform velocity.

如果作用在质点上所有的力是平衡的,质点将会保持静止或做做匀速直线运动。

2

1) the main manifestations of capacity主要的表现能力

2) the maximum unit load (stress)最大单位载荷(应力)3)stress-strain diagram 应力—应变图4)the simple tensile test 简单的拉伸试验5)the percentage elongation at rupture 断裂伸长率6)the ends of tensile specimens 拉伸试样的两端7)permanent deformation 永久变形8)the resulting load-displacement curve 由此产生的载荷位移曲线9)a substantial yielding of the material 大量产生的物质10)yield point 屈服点11) the transition from elastic to plastic behavior 从弹性到塑性的过度12)material property table 材料属性表13)plastic

deformation 塑性变形14)a specified standard length of the specimen 指定的标准式样长度15)at the moment of rupture 此刻的破裂16)short cylindrical specimens 短圆柱标本17)ductile materials 韧性材料18)high stress concentration 高应力集中19)ultimate tensile strength 极限抗拉强度20)strain hardening zone 应变硬化区1)A tensile test consists of slowly pulling a sample of material with a tensile load until it breaks. The ends of tensile specimens are usually enlarged to pr ovide extra area for gripping and to avoid having the sample break where it is being gripped. 拉伸试验包括慢慢加载拉伸载荷直到断裂,拉伸试件两端加粗为了提供装夹区域和避免试件断裂。2)The usual manner of conducting the test is to deform the specimen at a constant speed .For example, in the Universal testing machines, the motion between the fixed and moving cross heads can be controlled at a constant speed. 通常进行试验的方法就是使试件以恒定速度发生变形。例如,在万能拉伸试验机上,固定端和移动的十字滑块之间的变形是以恒定速度进行的。3)The load that must be applied to enforce this displacement rate varies as the test proceeds. This load F may be divided by the cross-sectional area A to obtain the stress

in the specimen at any time during the test. 随着实验的进行,用来产生位移的载荷是随位移的变化而变化。在实验中,载荷 F 除以横截面积 A 可以得到任意时刻点的应力。4)However actual measurement of ΔL is preferable where This is feasible. Stress and strain based on the initial (undeformed) dimensions, Ai and Li, are called engineering Stress and strain.

然而,在可行的位置的ΔL 的实际测量是更可取的,基于原始尺寸Ai 和Li 的应力和应变称为工程应力和工程应变。5)Ductile and brittle materials behave differently in compression test as well. The compression test is conducted on short Cylindrical specimens placed between parallel plates. 塑性和脆性材料在压缩试验中表现的特性是不相同的。压缩试验是把短圆柱形试件放在两平行平板之间进行的6)The compression test diagram for these materials retains.The qualitative features of the tension test diagram.The ultimate compressive strength of a brittle of a brittle material is determined in the same way as in tension. 材料压缩试验图保持了拉伸试验图性能上的特征。脆性材料的最大压缩强度与最大拉伸强度得到的方法相同。

第三单元

Virtually all machines contain shafts. The most common shape for shafts is circular and the cross section can be either solid or hollow (hollow shafts can result in weight savings). 几乎所有的机器都有轴,最常用的外形是圆形的,横截面是空心的或实心的圆形截面(空心轴可以减少重量)。 A shaft must have adequate torsional strength to transmit torque and not be overstressed. It must also be torsionally still enough so that one mounted component does not deviate excessively from its original angular position relative to a second component mounted on the same shaft. 一个轴必须有足够的扭转强度来传递扭矩而不会破坏,同样也必须有足够的扭转刚度,这样安装轴就不能过度偏离相对于安装在同一轴上第二个零件的原始位置。Shafts are mounted on bearings and transmit power through such devices as gears, pulleys, cams and clutches. These devices introduce forces which attempt to bend the shaft; hence, the shaft must be rigid enough to prevent overloading of the supporting bearings. 轴安装在轴承上通过齿轮,滑轮,凸轮和离合器这些装置传递力。这些装置可以产生使轴弯曲的力,所以轴必修有足够的刚性防止支撑轴承的过载。In addition,

the shaft must be able to sustain a combination of bending and torsion and bending. 另外,轴必须能承载弯扭组合的载荷,因此,这样就必须考虑弯扭组合的等效载荷。Components such as gears and pulleys are mounted on shafts by means of key. The design of the key and the corresponding keyway in the shaft must be properly evaluated. 齿轮和滑轮构件是用键的方式连接在轴上的,键和对应的键槽的设计必须进行估算。Another important aspect of shaft design is the method of directly connecting one shaft to another. This is accomplished by devices such as rigid and flexible couplings. 轴设计的另一个重要方面是直接连接两轴,通过刚性和柔性的联轴器装置来实现。

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1) herringbone gears 人字形齿轮

2)spiral gears 螺旋齿轮3)worm gears 蜗轮4) bevel gears(圆)锥齿轮,伞齿轮5)hypoid gears 准双曲面齿轮6)sizes of spur-gear teeth 轮齿尺寸7) the automotive rearaxle drives 汽车后桥驱动8) rack-and-pinion drives 齿条和小齿轮驱动9) diametral pitch 径节10) pitch circle 节圆11) the tangency point

切点12) pressure angles 压力角13) an involute curve 渐开线曲线14) the radial distant 径向距离15) at right angles 成直角16) the average number of teeth in contact 平均啮合齿数17) the reciprocal of the diametral pitch 径节的导数18) to change inches to millimeters 将英寸改为毫米19) a line perpendicular to the centerlines 垂直于中心线的线20) center distance between two meshed gears 两个互相啮合齿轮的中心距离1)Pressure angles for spur gears are usually 14.5 or 20 degress, although other values can be used. Meshing gears must have the same pressure angles. 译文:虽然直齿圆柱齿轮的压力角可以取很多其他值,但通常大多是在14.5 至20 度之间。互相啮合齿轮的压力角必须相同。2)The shape of the space between gear teeth is complex and varies with the number of teeth on the gear as well as tooth module, so most gear manufacturing methods generate the tooth flank instead of forming. 译文:由于齿轮齿数以及齿形的不同,齿轮齿侧间隙的形状也是复杂多样的,所以大多数齿轮的制造方法是范成发而不是成型法。3) Worm gears are used where high ratios are desired and where the shafts are nointersecting and at right angles. 译文:蜗轮蜗杆常用于那些要求高传动比同时两根轴不交

叉但成直角的场合。4) It has the great advantage that the cutting tool is a simple rack with(nearly) straight sided teeth which can easily be ground accurately. 译文:一个很大的优势在于刀具是在一个简单的齿条几乎可以直接准确地支起被磨损的轮齿。

5) Modern shapers cutting car gears can run at 2000 cutting per minute. The shape of the cutter is roughly the same as an involute gear but the tips of the teeth are rounded. 译文:现代牛头刨床削减汽车齿轮可以运行在每分钟2000。刀具的形状大致与渐开线齿轮的圆形轮齿相同。6) Bevel gears are often used when two shafts are at right angles to each other and their centenline extensions intersect; however,some bevel gears are at angles other than 90 degrees. 译文:锥齿轮常用于两轴互相垂直且它们中心线的延长线相交的场合下。可是,有些锥齿轮的轴线并非互相垂直。

5

1.plate cams 盘形凸轮

2. cylindrical cams 圆柱凸轮

3. the cam assemblies in automatic record players 录音机上的凸轮组件

4. cam

profiles 凸轮轮廓5. make a full-scale template 制造一个实尺样板 6. in the course of several revolutions of the cam 在凸轮转几转的过程中7. a tangential plate template 切向盘形凸轮8. a translation cam 移动凸轮9. the groove in the periphery of the cam 凸轮表面上的槽10. a guided vertical reciprocated follower 纵向做往复运动的从动件11. a constant-diameter cam 等径凸轮12. automatic washing machines 自动洗衣机13. a face cam 面凸轮14. the edge of a pivoted follower 摆动从动件的边缘15. a reciprocating knife-edged follower 一个做往复运动的刃口式从动件16. miniature snap-action electrical switches 微型速动电开关17. a pivoted flat-faced follower 一个转动的平面从动件18. air pilot values 空气试点值19. the abrupt change in cam profile 凸轮轮廓的突变20. a Scotch yoke mechanism 苏格兰约克机构1.The purpose of any cam is to produce a displacement of its follower is ofen used to produce additional displacement in another location. 使用凸轮的目的是使其从动件产生位移,次级从动件常用来在另一位置产生附加位移 2.The relative vertical position of point A with respect to B needs to be raised if the reaction value at B is excessive. 如果B 点的值超量,点 A 相对于 B 的垂直位置就要升高 3.In general, the

follower is considered to be the part that comes in contact with the cam profile. However, when a secondary follower is used, the motion of the secondary follower is dicatated by that of the primary follower. 总的来说,从动件是与凸轮轮廓相接触的零件。然而,当用次级从动件时,次级从动件的运动就需要通过主要从动件来实现4.The simplest type of follower is the reciprocating type that merely moves up and down (or in and out) with the rotation of the cam; the centerline can be either collinear with the cam centerline or offset from it. 最简单的从动件是随着凸轮的转动而仅作上下(或进出)往复运动的从动件,其中心线可与凸轮中心线共线,也可与之偏离。

5.Fasteners are devices which permit one part to be joined to a second part and, hence, they are involved in almost all designs. 紧固件是一种可以连接两个零件的部件,因此他们几乎在所有设计中都被涉及到。

6.Springs are mechanical members which are designed to give a relatively large amount of elastic deflection under the action of an externally applied load. 弹簧是一种被设计为在外部负载的作用下能发生相对大量弹性变形的机械部件。

6

1)a developing and demanding industry 产业的发展与要求

2)propeller shaft 螺旋轴3)suspension components 悬挂部件4)a sliding splined type of joint 滑动式花键5)tow rear axle shafts 双转向轴轴6)to mesh with a larger bevel gear 与较大的锥齿轮啮合7)the universal joints 万向节8)a steering wheel 转向盘9)unevenness of road surface 路面的不平整度10)the transverse line of the the axle shafts 该轴的横向线11)to cause excessive tyre wear 使轮胎磨损过度12)the exactly similar diameter 完全相似的直径13)quarter-elliptic leaf springs 四分之一椭圆钢板弹簧片14)the transmission of shock 震动的传播15)road surface variation 路面的变化16)the final-drive gears 最终传动齿轮17)the precise alignment of shaft 轴的精确定位18)a rotating drum 一个旋转的筒鼓19)a hand lever 手柄20)be locked in the one position 被锁定在一个位置1)The lubrication system provides a constant flow of filtered oil to all moving parts of the engine. The system consists of an oil pan to store the oil, a pump to circulate it, a filter to remove solid abrasive particles, and an oil

gauge or light in the driver’s compartment for checking purposes. 译:润滑系统提供了源源不断的过滤油给发动机的各个运动部件,该系统由一个油箱来储存油,一个泵来输送油,一个过滤装置除去固体磨料颗粒,并且在驾驶室里有个油压表或者指示灯来方便驾驶员检查油量是否充足。2)The drive line consists of mechanisms and units which transmit torque from the engine to the drive wheels and change torque and rpm in magnitude and direction. 译:传动系包括机制和单位,它将扭矩传送到驱动轮并改变转矩和转速的大小和方向。3)It has been seen that if the conditions are not very abnormal, sufficient amount of tyre slip taking place under running conditions would release these stresses completely. 译:可以看到,如果运行状况不是很正常,轮胎在行驶的情况下发生足够的滑移,这些压力就会被完全释放出来。4)Much effort is required to crank the engine during starting, since it is necessary to overcome friction in the moving engine components and the resistance offered by the charge being compressed. 译:发动机开始运行需要经过许多努力,比如必须要克服发动机运动部件之间的阻力和内部装置间的压力。5)The clutch is a friction device used to connect and disconnect a driving force from a driven

member .It is used in conjunction with an engine flywheel to provide smo0th engagement and disengagement of the engine and manual transmission. 译:离合器是一个将驱动力从驱动机构连接或者断开的摩擦装置,它由人力操控连接发动机的飞轮来提供平滑的连接与分离。

6)The differential is a gear system that transfers power from the drive shaft to the driving axles. It also permits one driving wheel to turn faster than the other to prevent skidding and scuffing of tires on turns. 译:差速器是一个将动力从主动轴传送到驱动轴的齿轮装置,它的存在可以允许一个驱动轮的速度比另一个更快从而避免轮胎在转动时发生打滑和擦伤。

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1.Green sand型砂

2.Pour molten metal into a prepared cavity 将熔融的金属倒入型腔中

3.More stable and refractory sands 耐熔砂

4.Be used to produce intricate molds 用来制作复杂铸型

5.Both ferrous and nonferrous materials 黑色及有色金属

6.Parting powder 分形砂

7.Be rammed 夯实

8.Pattern draft 拔模斜度

9.Sprues,runners and gates 直浇道,横浇道和内浇口10.A pouring basin 外浇口11.To make up for shrinkage losses 用

于弥补收缩损失12.The cope and the drag 上沙箱和下沙箱

13.Some organic bonding materials 一些有机黏合材料

14.Gross shrinkage 缩孔15.A bottom-pouring ladle 底部浇注铁水包16.The rate of solidification 凝固速率17.To affect the degree of liquid contraction 影响液体收缩的程度18.Columnar growth present at the mold wall 铸型中针状物的成长19.The feeding characteristics of the risering system 冒口的补缩特征20.Unwanted metal protrusions 多余的金属突起 1.The first stage in the production of sand casting must be the design and manufacture of a suitable pattern.Casting pattern has to be made larger than the finished casting size to allow for the shrinkage that takes place during solidification and cooling. 在型砂铸造生产中,第一阶段是必须设计和制造合适的模型,考虑到铸件在凝固和冷却期间产生的收缩,铸件模型的尺寸要比铸件的尺寸大。 2.If a hollow casting is to be made the pattern will include extension pieces so that spaces to accept the sand core are molded into the sand,These additional spaces in the mold are termed core prints. 如果铸造空心铸件时,模型上包含伸长杆便于在砂中放置砂芯的空间称为型芯座 3.Sand molds for the production of small and medium-sized castings are made in a molding box.The mold is made in two or more parts in order that the

pattern may be removed. 中小型尺寸的铸件砂型是在一个砂箱中制造,砂型由两部分或更多部分组成,以利于模型的顺利取出。 4.This process of filling and ramming may be done by hand but mold production is automated in a large foundry with the mold boxes moving along a conveyor,firstly to be filled with sand from hoppers and then to pass under mechanical hammers for ramming. 填充和夯实的过程可以手工完成,但在大型铸造中砂型的制造是自动完成的,砂箱随着传送带移动,首先被料斗中的砂子填满,然后通过机械锤被打实。 5.The risers should coincide with the highest points of the mold cavity so that the displaced air can readily escape from the mold. The sizes of risers should be such that the metal in them does not freeze too rapidly.

冒口应该与型腔的最高点相连接,使得进入的空气可以容易的从模型中溢出,冒口的尺寸应该足够大使模型中金属不会太快凝固。 6.When the metal that has been poured into a sand mold has fully solidified, the mold is broken and the casting is removed. The casting still has the runner and risers attached to it and there will be sand adhering to portions of the surface. 当熔融的金属被倾倒到砂型内并充分凝固以后,砂型将被打破取出铸件,铸件上依然带有横浇口和冒口并且依然有砂子粘在表面。

8

1).bulk deformation df metals 金属体积成形

2).forging, rolling, or extruding 锻造、轧制、挤压3).plastic deformation 塑性变形4).impact blows 影响冲击5).the recrystallization point of the metal 金属的再结晶点6).hot working and cold working 热加工和冷加工7).better surface finish 更好的表面光洁度8).hammer forging 锤锻造9).striking the hot metal 热金属的10).a slow squeezing acting 缓慢的挤压作用11).open dies ang closed dies 开模和封闭模具12).bevel gears with straight or helical teeth 圆锥齿轮跟直齿轮或者螺旋齿轮的齿13).impression dies 型腔模具14).each of die cavities 每个模腔15).mass production 大规模生产16).a homogeneous circumferential grain flow 均匀圆周颗粒流17).the three-dimensional description 三维描述18).computer simulation 计算机模拟19).hydraulic presses 液压机20).be rough- and finished-machined 是粗糙的并且经过机加工完成的 1.Forging means the shaping of metal by a series of hammer blows,or by slow application of pressure.The simplest example is a blacksmith's forging of a hot piece of

metal by hammering the work-piece on an anvil. 锻造是指通过一系列的捶打或缓慢的挤压使金属成形的过程。最简单的例子就是铁匠通过在铁砧上捶打一块热的金属来制造工件。

2.Heavy smith's forging is fundamentally similar,differing only in the scale of the operation,The work-piece may be an ingot of 100 tons and the deforming force provided by a massive forging hammer,but the whole process is controlled by the master smith,who decides each time where,and with what force ,the blow should take place. 铁匠们沉重的锻造工作基本上是相似的,不同的地方只是在于锻造的规模,工件可能是一个100 吨的金属锭,并且金属锭变形所需要的力是通过一把大规模的锻造锤提供,但是整个过程都是由主铁匠控制,决定每一次捶打在什么地方,用什么力量以及是否需要冷却。

3.Forging operations may be carried out using either forging hammers or forging presses.With a press,as opposed to a hammer,pressure is slowly applied and plastic deformation tends to occur fairly uniformly throughout the meterial. 锻造时可以用锻造锤,也可以用锻造压力机。与锻造锤不同,通过锻造压力机锻造时,压力被缓慢的施加,塑性变形往往会相当均匀地贯穿整个材料。

4.Forging hammers are of two basic types with the large hammer either dropping on to the work-piece accelerated by gravity alone or,as in the steam

hammer,accelerated by both gravity and steam pressure.

大型锻造锤有两种基本类型,一种捶打工件仅仅靠重力使大锤加速,另一种靠重力和蒸汽加速使大锤加速,如蒸汽锤。

5.Smith's or open-die forging is used for making very large forgings or when the number of forgings of a particular design is small.Open-die forging is also used to preform metal prior to final shaping by means of closed-die forging. 锤锻或开模锻适用于制造非常大锻件,或少量特殊设计锻件。开模锻还可以用于金属闭模锻之前的粗加工。

6.Closed-die forging involves the use of accurately machined die blocks.The capital cost of a pair of die blocks is high,but this is allowable when it is required to make forgings to close dimensional tolerances and in large quantity,as would be the case for,say,connecting rods fir the engine of a popular car. 闭模锻涉及到精确加工模块的使用。一对模具块的成本很高,但当锻件尺寸公差要求很高,数量很大情况下,闭模锻是适用的

9

1)carrying high-amperage current

带有高电流

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