Rock bit manufacturing method

摘要

A method of manufacturing a rock bit of previously formed lugs which will be welded to form a body. Initially, a shank end positioner means such as drilled holes are formed on the lug, which are then positioned on a mating receiver such as dowels in a fixture. The bearing end of the lug is clamped against a locator block to establish a predetermined relationship between the shank end and the bearing end of the lug. This relationship determines both the radial, axial and angular positions of the bearing and shank ends of the lug. Then, the faces of the lug are machined while held in this accurate aligment. When assembled and welded with similarly manufactured lugs, a bit of exceptional accuracy is produced in a cost effective manner. A slightly different position of the locator block permits the use of lugs of normal forging tolerances to be positioned to provide another location of the faces and bits of different sizes.