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U.S. Department of Energy
Office of Scientific and Technical Information

Drill tool

Patent ·
OSTI ID:6506102
A drill tool for rotary and/or percussion drilling with drill rod means within casing tube means comprises a centric cutting bit and an eccentric reamer cutter, both provided with hard metal inserts. For purposes of obtaining a life of the drill tool as long as possible the first frontal insert on the reamer cutter is positioned in front of the first peripheral insert when seen in the rotational direction during drilling, and the centric cutting bit provided with more inserts on the half of its front surface opposed to the reamer cutter during drilling than on the other half.
Assignee:
Santrade Ltd. (Switzerland)
Patent Number(s):
US 4440244
OSTI ID:
6506102
Country of Publication:
United States
Language:
English