MANUFACTURE OF GREASE FITTINGS AND BLANKS THEREFOR

摘要

A grease fitting is made by forming its outer shell in a series of cold forging steps to make a blank with the necessary thread blank at one end, a hexagonal center portion, and with a grease-fitting-mating nipple outline at the other end. Threads are rolled onto the thread blank, and the grease-gun-mating nipple is rolled to smooth and burnish its surface. The grease fitting is then successively drilled to make a hole of three different diameters to form the one-way valve ball seat and two ball spring clearance diameters. The ball and spring are inserted, and the end of the hole is formed over the end of the spring to capture the spring into place.