MANUFACTURE OF GREASE FITTINGS AND BLANKS THEREFOR

摘要

A grease fitting is made by cold forming a blank (48) into a member having a thread blank (66) at one end, a hexagonal center portion (70), and a grease-fitting-mating nipple outline (68) at the other end. Threads (104) are rolled onto the thread blank (66), and the grease-fitting-mating nipple outline (68) is formed into a grease-gun-mating nipple (96), which is then rolled to smooth and burnish its surface. The member is then successively drilled to make a hole (102) of three different diameters to form a one-way valve ball seat and two ball spring clearance diameters. A ball (110) and spring (112) are inserted into the hole (102), and then an end of the member is formed over an end of the spring (112) to capture the spring in place.