Title:
SHAPED SPARK DRILL
United States Patent 3500942
US Patent References:
Method of making bore holes
- - 1898926
Heat blasting tool with fluid jet
- - 2772346
Electric boring apparatus
- - 2822148
Method and apparatus for the drilling of rock
- - 3122212
Electro-drilling method and apparatus
- - 3179187
Method of making bore holes
- - 1898926
Heat blasting tool with fluid jet
- - 2772346
Electric boring apparatus
- - 2822148
Method and apparatus for the drilling of rock
- - 3122212
Electro-drilling method and apparatus
- - 3179187
Inventors:
Smith Jr., Noyes D.
Publication Date:
03/17/1970
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Export Citation:
Assignee:
SHELL OIL CO
Primary Class:
International Classes:
E21B7/15; E21B7/14; E21B7/00