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ABSTRACT
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 margin of processing, cutting force and internal stress progressively, revise the deformation after processing, can reach the specification requirement for the part finally .
In the 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.
Machine 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 technical requirements. The connecting rod in the practical production process, selection of connecting rod to the size of the head end and the small head hole
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精选资料
as the main positioning datum, and choice of big hole two side as a general locating datum. In order to ensure the size precision and shape precision of the small head hole, can be used for reference from the processing principle; ensure that the size of the first hole center distance accuracy requirements, can be used for reference each other the principle of processing.
Second: mainly on the fixture design method and steps.
Key words: Connecting rod;Deformation;Process;Fixture design
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