ApplicationNo. 647849 filed on 01/30/1991
US Classes:175/331, Rolling cutter bit or rolling cutter bit element175/374, Specific or diverse material175/426Insert
ExaminersPrimary: Bagnell, David
Attorney, Agent or Firm
International ClassE21B 010/16
AbstractAn improved rotary rock bit having a circumferential row of wear resistant inserts protruding from the gage surface of each rolling cone cutter. The inserts are designed to efficiently break and remove earth formations. Adequate clearance is provided around the gage inserts for chip formation, chip removal, and insert cooling. These rows of inserts provide reaming action to maintain borehole gage diameter after the primary gage cutting structure has worn or failed.