发明名称 Drilling bit with improved trailing edge vent
摘要 A rotating drill bit (10) includes a leg (12) and journal arm (14) on which is mounted a cone-shaped cutter (16). The cutter (14) rotates on the journal arm (14) by means of an anti-friction bearing including rollers (20) and ball bearings (26). Air is pumped through the journal arm (14) through conduits (30, 32 and 34). Air flows through the passages between rollers (20) and is collected in a cavity (52). The cavity (52) is vented to the borehole through a slot (54) in the trailing edge of the journal arm (14). A very narrow clearance in the order of a few thousandths of an inch is provided for rotational movement between the cone mouth shoulder (36) and last machined surface (40). Cone mouth shoulder (36) completely covers the last machined surface (40) around the entire periphery of the journal arm (14) except for the approximately 45 DEG slot (54) in the trailing edge of the journal arm (14).
申请公布号 US4813502(A) 申请公布日期 1989.03.21
申请号 US19880211660 申请日期 1988.06.28
申请人 DRESSER INDUSTRIES, INC. 发明人 DYSART, THEODORE R.
分类号 E21B10/24;(IPC1-7):E21B10/18;E21B10/22 主分类号 E21B10/24
代理机构 代理人
主权项
地址