BEARING INSERT SLEEVE FOR ROLLER CONE BIT.

摘要

An earth boring bit (11) has a bearing pin (13) with a sleeve (35)ounted on it. The sleeve is fixed against rotation but able to float relative to the bearing pin. A cone (23) fits over and forms a bearing surface (17) with the sleeve. The sleeve and bearing pin are configured to have a clearance between them that has a forward portion that progressively decreases in a rearward direction. The clearance progressively decreases in a forward direction from the rearward end of the sleeve. The cone and the sleeve are able to tilt in unison with each other relative to the bearing pin when the bit is loaded.