機械工程專業英語文章
隨着全球化進程的加快及新型工業化道路的發展,我國勞動力市場對機械工程人才的就業能力提出了更高的要求。下面是本站小編帶來的機械工程專業英語文章，歡迎閱讀!
Milling and Milling Cutter
銑削和銑刀
Milling is a machining process that is carried out by means of a multiedge rotating tool known asa milling cutter.
銑削是採用被稱爲銑刀的多刃旋轉刀具完成的機加工作業。
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.
在此工藝中金屬去除是通過銑刀的旋轉運動和工件的直線運動的組合實現的。銑削作業既可用於生成平面、輪廓面和螺旋麪也可用於切削螺紋和齒輪。
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.
在銑刀切削工件金屬時銑刀的每條切削刃都象一單獨的單刃刀具一樣作用。所以每條切削刃都適當的前後角。
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.
由於同一時間只有部分切削刃切削工件因此可以在對刀具壽命沒有不利影響的情況下承擔重型切削。事實上銑削允許的切削速度和進給比車削或鑽削高三到四倍。
Moreover, the quality of the surfaces machined by milling is generally superior to the qualityof surfaces machined by turning, shaping, or drilling.
此外,由銑削加工的表面質量通常優於車削、刨削或鑽削加工的表面質量。
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.
工業上可採用的銑刀類型衆多。連同銑牀是極通用機牀的事實使得銑牀成爲機加工車間的支柱。
As far as the direction of cutter rotation and workpiece feed are concerned, milling isperformed by either of the following two methods.
至於涉及到銑刀轉動的方向和工件的進給銑削可以通過下列兩種方法之一進行。
機械工程專業英語文章閱讀逆銑和順銑
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.
逆銑(傳統銑削)在逆銑中工件逆着銑刀轉動的方向進給如圖12.3a所示。就像在此圖中能看到的那樣切削深度(及作爲結果的載荷)隨着切削刃持續進入切削而逐漸增加。
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,這種工藝沒有衝擊載荷,從而保證了機牀的較平穩運行和較長壽命。通過逆銑所得機加工表面質量不是很高。然而逆銑仍經常被用在工業上,尤其是粗切削時。
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.
順銑(同向銑削)如同在圖12.3b中看到的那樣在順銑時刀具與工件之間接觸點上銑刀旋轉與進給方向一致。還可以看到當刀具進入工件切削時直接達到最大切削深度。
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.
這會導致一種衝擊,或突然加載。因此,這種方法只有當銑牀在進給螺栓上配備間隙消除器時才採用。這種方法的優點包括機加工表面質量較高和工件由於切削力向下作用而較容易夾緊。
機械工程專業英語文章學習Types of Milling Cutters
銑刀的類型
There is a wide variety of milling cutter shapes. Each of them is designed to perform effectively a specific milling operation.
銑刀的形狀類型很多。其中每種都是爲有效進行特定的銑削作業而設計的。
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,銑刀可以被描述爲具有旋轉實體形狀並將切削齒安裝在周邊或一到兩個端面上的多刃切削刀具。下面是常用銑刀類型的快速綜覽。
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.
平面銑刀,平面銑刀是一種盤狀切削刀具.它可以具有直齒或螺旋齒.如圖12.4a所示。這類銑刀總是安裝在臥式銑牀上.用於機加工平面。
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.
端面銑刀.端面銑刀也可用於機加工平面。它用螺栓固定在短刀杆的端部.而短刀杆則依次安裝於立式銑牀上。圖12.4b顯示了這類銑刀。
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.
平面金屬開槽鋸刃銑刀.圖12.4c顯示了一種平面金屬開槽鋸刃銑刀。可以看到它其實是一種很薄的平面銑刀。
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.
側銑刀.側銑刀用於切削狹槽、凹槽和花鍵槽。正如圖12.4d所示.它與平面銑刀十分相似.差別在於此類銑刀齒在側面。象平面銑刀的情況一樣.切削齒既可以是直的也可以是螺旋的。
