机械工程专业英语文章
随着全球化进程的加快及新型工业化道路的发展,我国劳动力市场对机械工程人才的就业能力提出了更高的要求。下面是本站小编带来的机械工程专业英语文章，欢迎阅读!
Milling and Milling Cutter
铣削和铣刀
Milling is a machining process that is carried out by means of a multiedge rotating tool known asa milling cutter.
铣削是采用被称为铣刀的多刃旋转刀具完成的机加工作业。
In this process, metal reMoval is achieved through combining the rotary motion of the millingcutter and linear motions of the workpiece simultaneously. Milling operations are employed inproducing flat, contoured and helical surfaces as well as for thread- and gear-cuttingoperation.
在此工艺中金属去除是通过铣刀的旋转运动和工件的直线运动的组合实现的。铣削作业既可用于生成平面、轮廓面和螺旋面也可用于切削螺纹和齿轮。
Each of the cutting edges of a milling cutter acts as an individual single-point cutter when itengages with the workpiece metal. Therefore, each of those cutting edges has appropriaterake and relief angles.
在铣刀切削工件金属时铣刀的每条切削刃都象一单独的单刃刀具一样作用。所以每条切削刃都适当的前后角。
Since only a few of the cutting edges are engaged with the workpiece at a time, heavy cuts canbe taken without adversely affecting the tool life. In fact, the permissible cutting speeds andfeeds for milling are three to four times higher than those for turning or drilling.
由于同一时间只有部分切削刃切削工件因此可以在对刀具寿命没有不利影响的情况下承担重型切削。事实上铣削允许的切削速度和进给比车削或钻削高三到四倍。
Moreover, the quality of the surfaces machined by milling is generally superior to the qualityof surfaces machined by turning, shaping, or drilling.
此外,由铣削加工的表面质量通常优于车削、刨削或钻削加工的表面质量。
A wide variety of milling cutters is available in industry. This, together with the fact that amilling machine is a very versatile machine tool, makes the milling machine the backbone of amachining workshop.
工业上可采用的铣刀类型众多。连同铣床是极通用机床的事实使得铣床成为机加工车间的支柱。
As far as the direction of cutter rotation and workpiece feed are concerned, milling isperformed by either of the following two methods.
至于涉及到铣刀转动的方向和工件的进给铣削可以通过下列两种方法之一进行。
机械工程专业英语文章阅读逆铣和顺铣
Up milling (conventional milling). In up milling the workpiece is fed against the direction ofcutter rotation, as shown in Fig.12.3a. As we can see in that figure, the depth of cut (andconsequently the load) gradually increases on the successively engaged cutting edges.
逆铣(传统铣削)在逆铣中工件逆着铣刀转动的方向进给如图12.3a所示。就像在此图中能看到的那样切削深度(及作为结果的载荷)随着切削刃持续进入切削而逐渐增加。
Therefore, the machining process involves no impact loading, thus ensuring smootheroperation of the machine tool and longer tool life. The quality of the machined surface obtainedby up milling is not very high. Nevertheless, up milling is commonly used in industry, especiallyfor rough cuts.
所以,这种工艺没有冲击载荷,从而保证了机床的较平稳运行和较长寿命。通过逆铣所得机加工表面质量不是很高。然而逆铣仍经常被用在工业上,尤其是粗切削时。
Down milling (climb milling). As can be seen in Fig.12.3b, in down milling the cutter rotationcoincides with the direction of feed at the contact point between the tool and the workpiece. Itcan also be seen that the maximum depth of cut is achieved directly as the cutter engages withthe workpiece.
顺铣(同向铣削)如同在图12.3b中看到的那样在顺铣时刀具与工件之间接触点上铣刀旋转与进给方向一致。还可以看到当刀具进入工件切削时直接达到最大切削深度。
This results in a kind of impact, or sudden loading. Therefore, this method cannot be usedunless the milling machine is equipped with a backlash eliminator on the feed screw. Theadvantages of this method include higher quality of the machined surface and easier clampingof workpieces, since the cutting forces act downward.
这会导致一种冲击,或突然加载。因此,这种方法只有当铣床在进给螺栓上配备间隙消除器时才采用。这种方法的优点包括机加工表面质量较高和工件由于切削力向下作用而较容易夹紧。
机械工程专业英语文章学习Types of Milling Cutters
铣刀的类型
There is a wide variety of milling cutter shapes. Each of them is designed to perform effectively a specific milling operation.
铣刀的形状类型很多。其中每种都是为有效进行特定的铣削作业而设计的。
Generally, a milling cutter can be described as a multiedge cutting tool having the shape of a solid of revolution, with the cutting teeth arranged either on the periphery or on an end face or on both. Following is a quick survey of the commonly used types of milling cutters.
通常,铣刀可以被描述为具有旋转实体形状并将切削齿安装在周边或一到两个端面上的多刃切削刀具。下面是常用铣刀类型的快速综览。
Plain milling cutter. A plain milling cutter is a disk-shaped cutting tool that may have either straight or helical teeth, as shown in Fig.12.4a. This type is always mounted on horizontal milling machines and is used for machining flat surfaces.
平面铣刀,平面铣刀是一种盘状切削刀具.它可以具有直齿或螺旋齿.如图12.4a所示。这类铣刀总是安装在卧式铣床上.用于机加工平面。
Face milling cutter. A face milling cutter is also used for machining flat surfaces. It is bolted at the end of a short arbor, which is in turn mounted on a vertical milling machine. Fig.12.4b indicates a milling cutter of this type.
端面铣刀.端面铣刀也可用于机加工平面。它用螺栓固定在短刀杆的端部.而短刀杆则依次安装于立式铣床上。图12.4b显示了这类铣刀。
Plain metal slitting saw cutter. Fig.12.4c indicates a plain metal slitting saw cutter. we can see that it actually involves a very thin plain milling cutter.
平面金属开槽锯刃铣刀.图12.4c显示了一种平面金属开槽锯刃铣刀。可以看到它其实是一种很薄的平面铣刀。
Side milling cutter. A side milling cutter is used for cutting slots, grooves, and splines. As shown in Fig.12.4d, it is quite similar to the plain milling cutter, the difference being that this type has teeth on the sides. As is the case with the plain cutter, the cutting teeth can be straight or helical.
侧铣刀.侧铣刀用于切削狭槽、凹槽和花键槽。正如图12.4d所示.它与平面铣刀十分相似.差别在于此类铣刀齿在侧面。象平面铣刀的情况一样.切削齿既可以是直的也可以是螺旋的。
