A method for reducing residual stress in a roller cone bit

摘要

A roller cone bit comprising stress reduction means for reducing residual stress at the barrier (e.g., weld) (29) and the perimeter area (23) of the head (15) adjacent the outer diameter to increase the service load capacity and the service life of the roller cone bit. The stress reduction means comprises an inner weld (31) formed from a first material adjacent the ball plug (27). The weld (29)is formed on the inner weld (31) from a second material that has a higher strength than the first material.