MEJORAS EN BARRENA PARA PERFORACION DE POZOS CON COJINETE DE FRICCION Y RETEN DE CORTADORA POR ARILLO

摘要

Disclosed herein is an earth boring bit having exclusively friction bearings and a snap ring cutter retainer. A lubrication system includes a compensator to control the pressure differential across the seal between the rotatable cutter and bearing shaft. This apparatus provides a bit of maximum bearing size and strength and simplifies construction for greater reliability.