-
-
Rotary drill bits
-
Patent number 4,823,892
-
Issue date Apr 25, 1989
-
NL Petroleum Products Limited
-
John Fuller
-
E21 - EARTH DRILLING MINING
-
Rotary drill bits
-
Patent number 4,804,049
-
Issue date Feb 14, 1989
-
NL Petroleum Products Limited
-
John D. Barr
-
B22 - CASTING POWDER METALLURGY
-
-
-
Rotary drill bits
-
Patent number 4,762,028
-
Issue date Aug 9, 1988
-
NL Petroleum Products Limited
-
Michael C. Regan
-
B23 - MACHINE TOOLS METAL-WORKING NOT OTHERWISE PROVIDED FOR
-
Rotary drill bits
-
Patent number 4,733,735
-
Issue date Mar 29, 1988
-
NL Petroleum Products Limited
-
John D. Barr
-
E21 - EARTH DRILLING MINING
-
Rotary drill bits
-
Patent number 4,720,371
-
Issue date Jan 19, 1988
-
NL Petroleum Products Limited
-
David Shirley
-
B22 - CASTING POWDER METALLURGY
-
Rotary drill bits
-
Patent number 4,718,505
-
Issue date Jan 12, 1988
-
NL Petroleum Products Limited
-
John Fuller
-
E21 - EARTH DRILLING MINING
-
Cutter assemblies for rotary drill bits
-
Patent number 4,705,122
-
Issue date Nov 10, 1987
-
NL Petroleum Products Limited
-
Michael T. Wardley
-
B23 - MACHINE TOOLS METAL-WORKING NOT OTHERWISE PROVIDED FOR
-
Rotary drill bits
-
Patent number 4,700,790
-
Issue date Oct 20, 1987
-
NL Petroleum Products Limited
-
David Shirley
-
E21 - EARTH DRILLING MINING
-
-
Rotary drill bits
-
Patent number 4,697,654
-
Issue date Oct 6, 1987
-
NL Petroleum Products Limited
-
John D. Barr
-
E21 - EARTH DRILLING MINING
-
-
-
-
-
Rotary drill bits
-
Patent number 4,596,296
-
Issue date Jun 24, 1986
-
NL Petroleum Products Limited
-
Terry R. Matthias
-
E21 - EARTH DRILLING MINING
-
Rotary drill bits
-
Patent number 4,577,706
-
Issue date Mar 25, 1986
-
NL Petroleum Products Limited
-
John D. Barr
-
E21 - EARTH DRILLING MINING