A method for reducing residual stress in a roller cone bit

摘要

A roller cone bit (11) has a ball retention system to secure the cones (17) to the head (15). A radial ball race (19) includes a ball way (21) with a ball plug (27) to keep the balls (25) in the ball race. The ball plug (27) is secured to the head by welding. Any residual stress in the weld region is alleviated by applying heat or vibration to promote relaxation.