连杆加工工艺流程(毕业设计)

目录

摘要 (1)

第一章概述 (5)

1.1机床专用夹具分类与组成 (5)

1.2课题研究内容 (6)

第二章连杆加工工艺 (7)

2.1连杆结构特点 (7)

2.2连杆的主要技术要求 (7)

2.3连杆的材料和毛坯 (9)

2.4连杆的机械加工工艺过程 (10)

2.5连杆的机械加工工艺过过程分析 (12)

2.6确定加工余量计算尺寸及公差 (14)

2.7连杆出品的检验 (15)

第三章总结 (16)

参考文献 (18)

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摘要

连杆是柴油机的主要传动件之一，本文主要论述了连杆的加工工艺及其夹具设计。连杆的尺寸精度、形状精度以及位置精度的要求都很高，而连杆的刚性比较差，容易产生变形，因此在安排工艺过程时，就需要把各主要表面的粗精加工工序分开。逐步减少加工余量、切削力及内应力的作用，并修正加工后的变形，就能最后达到零件的技术要求。连杆的主要加工表面为大、小头孔和两端面，较重要的加工表面为连杆体和盖的结合面及连杆螺栓孔定位面，次要加工表面为轴瓦锁口槽、油孔、大头两侧面及体和盖上的螺栓座面等。

在连杆加工中有两个主要因素影响加工精度：

（1）连杆本身的刚度比较低，在外力（切削力、夹紧力）的作用下容易变形。

（2）连杆是模锻件，孔的加工余量大，切削时将产生较大的残余内应力，并引起内应力重新分布。

通过对汽车连杆的机械加工工艺及对粗加工大头孔夹具和铣结合面夹具的

设计，主要归纳为以下两个方面：

第一方面：连杆件外形较复杂，而刚性较差。且其技术要求很高，所以适

当的选择机械加工中的定位基准,是能否保证连杆技术要求的重要问题之一。在

连杆的实际加工过程中，选用连杆的大小头端面及小头孔作为主要定位基面，

同时选用大头孔两侧面作为一般定位基准。为保证小头孔尺寸精度和形状精度，

可采用自为基准的加工原则；保证大小头孔的中心距精度要求，可采用互为基

准原则加工。

第二方面：主要是关于夹具的设计方法及其步骤。

关键词: 连杆变形加工工艺夹具设计

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Abstracts

The connecting rod is one of the main driving medium of diesel engine, this text expounds mainly the machining technology and the design of clamping device of the connecting rod. The precision of size, the precision of profile and the precision of position , of the connecting rod is demanded highly , and the rigidity of the connecting rod is not enough, easy to deform, so arranging the craft course, need to separate the each main and superficial thick finish machining process. Reduce the function of processing the surplus , cutting force and internal stress progressively , revise the deformation after processing, can reach the specification requirement for the part finally .

Connecting rod is one of the main processing surface is large, the small head hole and both ends of the machined surface, is important for the connecting rod body and cover joint surface and the connecting rod bolt hole locating surface, secondary processing surface for bearing locking grooves, oil hole, head and body and a cover on the two sides of the bolt seat surface.

In the machining of connecting rod are two major factors that affect the machining precision:

(1) connecting rod itself stiffness is relatively low, in the external forces ( cutting force, clamping force ) under the action of easy deformation.

(2) connecting rod is die forgings, hole machining allowance, cutting will produce bigger residual stress, and stress redistribution caused by.

The automobile connecting rod machining process and the rough machining and milling combined with big hole clamp surface fixture design, mainly divided into the following two aspects:

The first aspect: connecting rod parts with complicated shape, while the poor rigidity. And the very high technical requirements, so the appropriate selection of mechanical processing in the locating datum, can ensure the connecting rod is one of the important problems of

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