Title:
Rock core drill head
United States Patent 1961362


Inventors:
Howard, John H.
Application Number:
US53821031A
Publication Date:
06/05/1934
Filing Date:
05/18/1931
Assignee:
GLOBE OIL TOOLS CO
Primary Class:
Other Classes:
175/255, 175/339
International Classes:
E21B10/06; E21B10/18; E21B10/20; E21B21/12
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