Machining method and device for large pan head oil groove bolt

Abstract

The invention discloses a machining method for a large pan head oil groove bolt. The method comprises the steps of selecting a raw material used for machining the bolt; putting the raw material into acold header, and upsetting a rod part of the raw material by using the cold header; upsetting the head of the raw material by using the cold header, and upsetting a chamfer at the bottom of the rod part; upsetting a head flange of the raw material by using the cold header, and upsetting a polished rod between the head flange and the rod part; an upsetting an oil groove in the lower portion of thehead flange through the cold header. The cold header is used for cold heading the rod part of the bolt, the head flange, the chamfer at the bottom of the rod part, the polished rod between the head flange and the rod part and the oil groove in the lower part of the head flange by utilizing a cold heading process, so that the service life of a die is greatly prolonged, the size consistency of theoil groove is good, the production efficiency is improved, the manufacturing period is shortened, the cost is saved, profits are increased, and stable production of a large batch of bolts is ensured.

Description

technical field [0001] The invention relates to the technical field of fastener production, in particular to a processing method and device for a large pan-head oil groove bolt. Background technique [0002] Large pan-head oil groove bolts are widely used in the field of automotive fasteners. They are widely used fasteners. The main consideration is that the R angle under the bolt head and the interference of the counterpart's aperture cause the bolt support surface and the counterpart's plane to not fit, resulting in bolts There is a possibility of loosening and detachment in the future, so the R angle under the bolt head is used as an oil groove to effectively solve the situation that it does not fit with the counterpart. [0003] The oil groove is very small. This is the difficulty of this type of product. Because the oil groove is small, the boss of the forming mold is also very small. The mold is easy to collapse, the mold rod is easy to crack, the mold life is low, the...

AI Technical Summary

Problems solved by technology

[0003]The oil groove is very small. This is the difficulty of this type of product. Due to the small oil groove, the boss of the forming mold is also very small, and the mold is easy to collapse. Easy to crack, low mold life, high cost, low production efficiency, poor product quality, and poor consistency

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