機(jī)械工程英語

1、機(jī)械工程專業(yè)英語機(jī)械工程專業(yè)英語Major: Major: Mechanical Engineering and AutomationMechanical Engineering and AutomationDirection: Direction: Mold design and ManufactureMold design and ManufactureClass:Class:L121&124L121&124Lushan College of Guangxi University of TechnologyGrinding is a manufacturing process that i

2、nvolves the removal of metal by employing a rotating abrasive wheel. The latter simulates a milling cutter with an extremely large number of miniature cutting edges. 磨削是通過采用旋轉(zhuǎn)磨輪去除金屬的制造工藝。磨輪用非常大量的微型切削刃模仿銑刀進(jìn)行切削。miniature minitadj.小型的, 微小的n.微型復(fù)制品, 微小模型；微型畫, 微型人像畫raindiSketch of how abrasive particles i

3、n a grinding wheel remove material from a workpieceGenerally, grinding is considered to be a finishing process that is usually used for obtaining high-dimensional accuracy and better surface finish. Grinding can be performed on flat, cylindrical, or even internal surfaces by employing specialized ma

4、chine tools, which are referred to as grinding machines.一般而言，磨削被認(rèn)為是一種通常用于獲得高尺寸精度和較好表面光潔度的精加工作業(yè)。磨削通過采用被稱為磨床的特殊機(jī)床能在平面、圓柱面甚至內(nèi)表面上進(jìn)行。Obviously, grinding machines differ in construction as well as capabilities, and the type to be employed is determined mainly by the geometrical shape and nature of the sur

5、face to be ground, e.g., cylindrical surfaces are ground on cylindrical grinding machines.顯然，磨床根據(jù)結(jié)構(gòu)和功能的不同有所區(qū)別，使用何種形式的磨床主要取決于被磨削表面的幾何形狀和物理性質(zhì)。例如，圓柱面在外圓磨床上磨削。capability ,kepblti:n.能做某事的素質(zhì);能力；尚未發(fā)揮的天資或素質(zhì)Type of Grinding Operations磨削作業(yè)的類型1. Surface grinding. As the name surface grinding suggests, this ope

6、ration involves grinding of flat or plane surfaces. Fig.8.1 indicates the two possible variations, either a horizontal or vertical machine spindle.1. 表面磨削：表面磨削：就像其名稱暗示的那樣，表面磨削和平面磨削直接有關(guān)。圖8.1表示了兩種可能的變體：臥式磨床主軸或立式磨床主軸。周磨周磨端磨端磨床身床身頭架頭架砂輪修整器砂輪修整器砂輪砂輪砂輪架砂輪架工作臺工作臺橫向橫向手輪手輪縱向縱向手輪手輪In the first case (horizonta

7、l spindle), the machine usually has a planer-type reciprocating risiprkeiti往復(fù)式table on which the workpiece is held. However, grinding machines with vertical spindles can have either a planer type table like that of the horizontal-spindle machine or a rotating worktable.在第一種情況(臥式主軸)，臥式磨床通常具有安裝工件的刨床式往

8、復(fù)工作臺。而立式主軸磨床既可以像臥式主軸磨床那樣具有刨床式工作臺也可以具有旋轉(zhuǎn)工作臺。planer pleinn.刨工,刨機(jī)Also, the grinding action in this case is achieved by the end face of the grinding wheel (Fig.8.1b), contrary to the case of horizontal-spindle machines, where the workpieces ground by the periphery of the grinding wheel. 而且在這種情況下，磨削動作是通過

9、砂輪端面完成的(圖8.1b)，這與通過砂輪周邊磨削工件的臥式主軸磨床正好相反。contrary kntrriadj.相反的, 相違的n.相反, 反面, 對立面periphery prfri:n.外圍;邊緣；(神經(jīng))末梢周圍Fig.8.1a and b also indicate the equations to be used for estimating the different parameters of the grinding operation, such as the machining time and the rate of metal removal.圖8.1a和b同時簡述

10、了用于估計諸如加工時間和金屬去除率之類的磨削作業(yè)不同參數(shù)的方程式。During the surface-grinding operations, heavy workpieces are either held in fixtures or clamped on the machine table by strap clamps and the like, whereas smaller workpieces are usually held by magnetic chucks.在平面磨削時，重的工件用夾具固定或用壓板等夾緊在磨床工作臺上，而小的工件則通常是用電磁卡盤固定的。chuck英 t

11、k 美 tk n. （牛）頸部到肩部的肉；咕咕（呼雞聲），砸砸（呼馬聲）；拋出；親愛的 vt. 機(jī)械工程用卡盤夾緊；（口語）拋出，扔出；咕咕（咯咯、嘟嘟）地叫；（美國）辭職2. Cylindrical grinding. In cylindrical grinding, the workpiece is held between centers during the grinding operation, and the wheel rotation is the source and cause for the rotary cutting motion, as shown in Fig.8

12、.2. In fact, cylindrical grinding can be carried out by employing any of the following methods:2. 圓柱面磨削：圓柱面磨削：在圓柱面磨削中，作業(yè)時工件支撐在兩頂尖之間，砂輪轉(zhuǎn)動是導(dǎo)致回轉(zhuǎn)切削運動的動力源，如圖8.2所示。實際上，圓柱面磨削能通過采用下列任意方法來實現(xiàn)：(1) The transverse method, in which both the grinding wheel and the workpiece rotate and longitudinal linear feed is a

13、pplied to enable grinding of the whole length. The depth of cut is adjusted by the cross feed of the grinding wheel into the workpiece.(1) 橫向方法：這種方法中砂輪與工件均旋轉(zhuǎn)且采用線性縱向進(jìn)給以保證能磨削整個長度。切削深度通過改變砂輪對工件的橫向進(jìn)給來進(jìn)行調(diào)整。transverse trnsv:sadj.橫向的;橫斷的;橫切的；橫截的n.橫向物;橫軸;橫斷面；橫截軸；橫肌longitudinal lnditju:dinladj.經(jīng)度的,縱向的(2) The

14、 plunge-cut method, in which grinding is achieved through the cross feed of the grinding wheel and no axial feed is applied. As you can see, this method can be applied only when the surface to be ground is shorter than the width of the grinding wheel used.(2) 插入-切削方法：這種方法通過砂輪的橫向進(jìn)給完成磨削而不采用軸向進(jìn)給。正如料想的那

15、樣，這種方法只在要磨削表面比所用砂輪寬度短時才使用。plunge plndvi.顛簸vt. & vi.(使)陷入n.投身入水；猛跌, 驟降(3) The full-depth method, which is similar to the transverse method except that the grinding allowance is removed in a single pass. This method is usually recommended when grinding short rigid shafts.(3) 全深度方法：這種方法除了一次加工就能去除磨削余量外其

16、它與橫向方法相同。這種方法通常在磨削較短剛性軸時推薦使用。 Internal grinding. Internal grinding is employed for grinding relatively short holes, as shown in Fig.8.3. The workpiece is held in a chuck or a special fixture. Both the grinding wheel and the workpiece rotate during the operation and feed is applied in the longitudina

17、l direction. 內(nèi)表面磨削：內(nèi)表面磨削：內(nèi)表面磨削用于相對較短的孔，如圖8.3所示。工件安裝在卡盤或特殊夾具上。作業(yè)時砂輪和工件都回轉(zhuǎn)并且采用縱向進(jìn)給。longitudinal lnditju:dinladj.經(jīng)度的,縱向的縱磨法縱磨法磨內(nèi)孔磨內(nèi)孔橫磨法橫磨法磨內(nèi)孔磨內(nèi)孔利用端磨利用端磨頭磨平面頭磨平面Any desired depth of cut can be obtained by the cross feed of the grinding wheel. A variation from this type is planetary internal grinding, wh

18、ich is recommended for heavy workpieces that cannot be held in chucks. 通過砂輪的橫向進(jìn)給能得到任意所需的切削深度。這種方法的一個變體是行星式內(nèi)表面磨削，當(dāng)工件較重不能用卡盤固定時推薦使用。planetary pln,teri:adj.(似)行星的In that case, the grinding wheel not only spins使旋轉(zhuǎn)around its own axis but also rotates around the centerline of the hole that is being ground

19、.在這種情況下，砂輪不但繞自身軸線回轉(zhuǎn)，同時還繞被磨削孔的中心線旋轉(zhuǎn)。 Centerless grinding. Centerless grinding involves passing a cylindrical workpiece, which is supported by a rest blade, between two wheels, i.e., the grinding wheel and the regulating or feed wheel. 無心磨削：無心磨削：無心磨削用于加工圓柱形工件，工件由托板支撐，在兩輪即砂輪和調(diào)節(jié)或進(jìn)給輪之間通過去。The grinding wh

20、eel does the actual grinding, while the regulating wheel is responsible for rotating the workpiece as well as generating the longitudinal feed. This is possible because of the frictional characteristics of that wheel, which is usually made of rubber-bonded abrasive.砂輪完成實際磨削，而調(diào)節(jié)輪負(fù)責(zé)旋轉(zhuǎn)工件和產(chǎn)生縱向進(jìn)給。由于調(diào)節(jié)輪通常

21、用橡膠粘結(jié)的磨料制成，其摩擦特性使這成為可能。As can be seen in Fig.8.4, the axis of the regulating wheel is tilted at a slight angle with the axis of the grinding wheel. Consequently, the peripheral velocity of the regulating wheel can be resolved into two components, namely, workpiece rotational speed and longitudinal f

22、eed. 正如在圖8.4中所看到的那樣，調(diào)節(jié)輪的軸與砂輪軸傾斜一個微小角度。因此調(diào)節(jié)輪的圓周速度可以分解為兩個分量，即工件回轉(zhuǎn)速度和縱向進(jìn)給。peripheral prfrladj.非本質(zhì)的;非主要的, 次要的, 外圍的；周圍的, 邊緣的n.(計算機(jī)的)外圍設(shè)備, 周邊設(shè)備These can be given by the following equations: VworkpieceVregulating wheelcos Axial feedVregulating wheelcsin Where c is a constant coefficient to account for the

23、slip between the workpiece and the regulating wheel (c=0.940.98).其值可由下列公式給出： V工件V調(diào)節(jié)輪cos 軸向進(jìn)給V調(diào)節(jié)輪csin 式中c是考慮工件和調(diào)節(jié)輪之間滑動的恒定系數(shù)(c=0.940.98)。 coefficient ,kfntn.系數(shù)；(測定某種質(zhì)量或變化過程的)率,程度;系數(shù) The velocity of the regulating wheel is controllable and is used to achieve any desired rotational speed of the workpiec

24、e. The angle is usually taken from 1to 5and the larger the angle, the larger the longitudinal feed would be. 調(diào)節(jié)輪的速度是可控的并被用于實現(xiàn)工件任意所需的轉(zhuǎn)動速度。角通常取1到 5，這角度越大則縱向進(jìn)給也將越大。angle ln.角, 角度；觀點angel eindln.天使；可愛的人; 品行高潔的人When is taken as 0, i.e., the two axes of the grinding and regulating wheels are parallel, the

25、re is no longitudinal feed of the workpiece.當(dāng)取0時，即砂輪和調(diào)節(jié)輪軸線平行時，則工件沒有縱向進(jìn)給。parallel prleladj.(指至少兩條線)平行的Grinding Wheels 砂輪 Grinding wheels are composed of abrasive grains having similar size and a binder. The actual grinding process is performed by the abrasive grains. Pores between the grains within t

26、he binder enable the grains to act as separate single-point cutting tools. 砂輪由具有相近尺寸的磨料顆粒和粘合劑組成。實際磨削作業(yè)由磨粒完成。在粘合劑中磨粒之間的孔隙使磨粒能象獨立的單刃切削刀具一樣工作。These pores also provide space for the generated chips, thus preventing the wheel from clogging. In addition, pores assist the easy flow of coolants to enable ef

27、ficient and prompt removal of the heat generated during the grinding process.這些孔隙同時還為產(chǎn)生的切屑提供空間以防砂輪堵塞。另外孔隙幫助冷卻液容易流動，從而使在磨削作業(yè)中產(chǎn)生的熱量能有效而迅速地散發(fā)。chip tipn.碎片；缺口；炸馬鈴薯條prompt prmptadj.立刻的, 迅速的, Grinding wheels are identified based on their shape and size, kind of abrasive, grain size, binder, grade (hardnes

28、s), and structure. 砂輪根據(jù)它們的形狀和尺寸、磨料的類型、磨粒的大小、粘合劑、等級(硬度)和結(jié)構(gòu)組織來分類。 Shape and size of grinding wheels. Grinding wheels differ in shape and size, depending upon the purpose for which they are to be used. Various shapes are shown in Fig.8.5 and include the following types: 砂輪的形狀和尺寸：砂輪的形狀和尺寸：根據(jù)砂輪的用途，它們的形狀和

29、尺寸是不同的。各種形狀如圖8.5所示，其中包括:1)Straight wheels used for surface, cylindrical, internal, and centerless grinding.2)Bevelled-face or tapered wheels used for grinding threads, gear teeth, and the like.3)Straight recessed wheels for cylindrical grinding and facing.1)用于表面、圓柱面、內(nèi)部和無心磨削的直輪。2)用于磨削螺紋、齒輪輪齒之類的斜面或錐形輪

30、。3)用于圓柱面和端面磨削的直凹輪。bevel bevln.斜邊和斜面；斜角規(guī)recess rises把某物放在墻壁的凹處；將(墻)做成凹形; 在(墻)上做壁龕4)Abrasive disks for cutoff and slotting operations. (thickness 0.02 up to 0.2in. (0.5 to 5mm).5)Cylinders, straight cups, and flaring cups are used for surface grinding with the end face of the wheel.4)用于切斷和開槽作業(yè)的砂輪片(其厚度

31、從0.02到0.2英寸(0.5到5毫米)。5)用其端面進(jìn)行表面磨削的圓柱、直杯及外展杯狀砂輪。 The main dimensions of a grinding wheel are the outside diameter D, the bore diameter d, and the height H. These dimensions vary widely, depending upon the grinding process for which the wheel is to be used. 砂輪的主要尺寸有外徑D、孔徑d和厚度H。根據(jù)采用砂輪的磨削工藝，這些尺寸變化很大。bor

32、e b:vt.令人厭煩vt. & vi.挖, 掘, 鉆, 開鑿(洞、井、隧道等)n.令人討厭的人或事物, 麻煩 Kind of abrasive. Grinding wheels can be made of natural abrasives such as quartzkw:ts, emeryemri, and corundumkrndm or of industrially prepared chemical compounds such as aluminum oxideksaid or silicon carbide (known as carborundum). 磨料的類型：磨料的

33、類型：砂輪可以由象石英、金剛砂、剛玉之類的自然磨料制成，或者由象氧化鋁或碳化硅(也稱人造金剛砂)之類的工業(yè)制備的化學(xué)化合物制成。Generally, silicon carbide grinding wheels are used when grinding low-tensile-strength materials like cast iron, whereas aluminum oxide wheels are employed for grinding high-strength metals such as alloy steel, hardened steel, and the l

34、ike.當(dāng)磨削象鑄鐵類低拉伸強度材料時，一般采用碳化硅砂輪，而磨削合金鋼、淬火鋼等高強度金屬則要用氧化鋁砂輪。 Grain size of abrasive used. As you may expect, the grain size of the abrasive particles of the wheel plays a fundamental role in determining the quality of ground surface obtained. 所用磨粒的尺寸：所用磨粒的尺寸：正如料想的那樣，砂輪磨粒的尺寸對決定所得磨削表面的質(zhì)量起著根本的作用。The finer t

35、he grains, the smoother the ground surface is. Therefore, coarse-grained grinding wheels are used for roughing operations, whereas fine-grained wheels are employed in final finishing operations.磨粒越細(xì)，磨削表面越光滑。所以，粗粒砂輪用于粗加工，而細(xì)粒砂輪則用于最后精加工。coarse-grained k:sgrend, krs-adj.紋理粗糙的,粗魯?shù)?粗鄙的 The grade of the bo

36、nd. The grade of the bond is actually an indication of the resistance of the bond to pulling off the abrasive grains from the grinding wheel. Generally, wheels having hard grades are used for grinding soft materials and vice versa. 粘結(jié)體的等級：粘結(jié)體的等級：粘結(jié)體的等級實際上是其抵抗將磨粒從砂輪上拉脫的指標(biāo)。一般而言，具有較硬等級的砂輪用于磨削較軟材料，反之亦然。

37、vice versa ,vas v:s, ,vasadv.反過來也一樣If a hard-grade wheel were to be used for grinding a hard material, the dull grains would not be pulled off from the bond quickly enough, thus impeding the self-dressing process of the surface of the wheel and finally resulting in clogging of the wheel and burns on

38、 the ground surface. 如果較硬等級的砂輪用于磨削較硬材料，磨鈍的磨粒將不能足夠快地脫離粘結(jié)體，這會妨礙砂輪表面的自修復(fù)，最終導(dǎo)致砂輪的堵塞并在被磨表面留下灼斑。impede impi:dvt.阻礙, 妨礙, 阻止In fact, the cutting properties of all grinding wheels must be restored periodically by dressing with a cemented carbide roller or a diamond tool to give the wheel the exact desired shape an