机械工程英语翻译unit

the wheel rotation is the source and cause
for the rotary cutting motion, as shown in
Fig.8.2. In fact, cylindrical grinding can be
carried out by employing any of the
following methods:
2. 圆柱面磨削：在圆柱面磨削中，作业时工
件支撑在两顶尖之间，砂轮转动是导致回 转切削运动的动力源，如图8.2所示。实际
上，圆柱面磨削能通过采用下列任意方法
来实现：
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(1) The transverse method, in which both the grinding wheel and the workpiece rotate and longitudinal linear feed is applied to enable grinding of the whole length. The depth of cut is adjusted by the cross feed of the grinding wheel into the workpiece.
在第一种情况(卧式主轴)，卧式磨床通常具有 安装工件的刨床式往复工作台。而立式主 轴磨床既可以像卧式主轴磨床那样具有刨 床式工作台也可以具有旋转工作台。
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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.
无心磨削：无心磨削用于加工圆柱形工 件，工件由托板支撑，在两轮即砂轮和调 节或进给轮之间通过去。
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The grinding wheel 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.
两种可能的变化：卧式磨床主轴或立式磨
床主轴。
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In the first case (horizontal spindle), the machine usually has a planer-type reciprocating 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.
通过砂轮的横向进给能得到任意所需的切削 深度。这种方法的一个变体是行星式内表 面磨削，当工件较重不能用卡盘固定时推 荐使用。
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In that case, the grinding wheel not only spins around its own axis but also rotates around the centerline of the hole that is being ground.
Grinding is a manufacturing process that involves 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.
grinding machines.
一般而言，磨削被认为是一种通常用于获得
高尺寸精度和较好表面光洁度的精加工作
业。磨削通过采用被称为磨床的特殊机床 能在平面、圆柱面甚至内表面上进行。
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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 surface to be ground, e.g., cylindrical surfaces are ground on cylindrical grinding machines.
磨削是通过采用旋转磨轮去除金属的制 造工艺。磨轮用非常大量的微型切削刃模 仿铣刀进行切削。
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Generally, grinding is considered to be a
finishing process that is usually used for
obtaining high-dimensional accuracy and
在平面磨削时，重的工件用夹具固定或用压 板等夹紧在磨床工作台上，而小的工件则 通常是用电磁卡盘固定的。
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2. Cylindrical grinding. In cylindrical
grinding, the workpiece is held between
centers during the grinding operation, and
better surface finish. Grinding can be
performed on flat, cylindrical, or even
internal surfaces by employing specialized
machine tools, which are referred to as
(1) 横向方法：这种方法中砂轮与工件均旋转 且采用线性纵向进给以保证能磨削整个长 度。切削深度通过改变砂轮对工件的横向 进给来进行调整。
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(2) The 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.
在这种情况下，砂轮不但绕自身轴线回转， 同时还绕被磨削孔的中心线旋转。
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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.
而且在这种情况下，磨削动作是通过砂轮端 面完成的(图8.1b)，这与通过砂轮周边磨削 工件的卧式主轴磨床正好相反。
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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.
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：就像其名称暗示的那样，表面 磨削和平面磨削直接有关。图8.1表示了
内表面磨削：内表面磨削用于相对较短 的孔，如图8.3所示。工件安装在卡盘或特 殊夹具上。作业时砂轮和工件都回转并且 采用纵向进给。
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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, which is recommended for heavy workpieces that cannot be held in chucks.
(2) 插入-切削方法：这种方法通过砂轮的横 向进给完成磨削而不采用轴向进给。正如 料想的那样，这种方法只在要磨削表面比 所用砂轮宽度短时才使用。
Biblioteka Baidu
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(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：这种方法除了一次加工就能 去除磨削余量外其它与横向方法相同。这 种方法通常在磨削较短刚性轴时推荐使用。
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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 longitudinal direction.
图8.1a和b同时简述了用于估计诸如加工时间 和金属去除率之类的磨削作业不同参数的 方程式。
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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.
显然，磨床根据结构和功能的不同有所区别， 使用何种形式的磨床主要取决于被磨削表 面的几何形状和物理性质。例如，圆柱面 在外圆磨床上磨削。
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Type of Grinding Operations 磨削作业的类型
1. Surface grinding. As the name surface
grinding suggests, this operation involves