Inventor
BARR JOHN D
GB41 patents
⚠️ This page may combine multiple inventors who share the name “BARR JOHN D”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
NL INDUSTRIES INC
11 patentsUS4593777AJun 10, 1986
Drag bit and cutters
NL INDUSTRIES INC162 citations99
US4558753ADec 17, 1985
Drag bit and cutters
NL INDUSTRIES INC94 citations96
US4505342AMar 19, 1985
Drill bit
NL INDUSTRIES INC63 citations96
US4727946AMar 1, 1988
Rotary drill bits
NL INDUSTRIES INC29 citations93
US4676324AJun 30, 1987
Drill bit and cutter therefor
NL INDUSTRIES INC31 citations93
US4640375AFeb 3, 1987
Drill bit and cutter therefor
NL INDUSTRIES INC41 citations93
US4660659AApr 28, 1987
Drag type drill bit
NL INDUSTRIES INC48 citations91
US4711144ADec 8, 1987
Drill bit and method of manufacture
NL INDUSTRIES INC27 citations89
US4605157AAug 12, 1986
Drill bit manufacturing method
NL INDUSTRIES INC24 citations79
US4669556AJun 2, 1987
Drill bit and cutter therefor
NL INDUSTRIES INC13 citations74
US4570725AFeb 18, 1986
Drill bit cutter
NL INDUSTRIES INC15 citations74
NL PETROLEUM PROD
7 patentsUS4804049AFeb 14, 1989
Rotary drill bits
NL PETROLEUM PROD60 citations96
US4694919ASep 22, 1987
Rotary drill bits with nozzle former and method of manufacturing
NL PETROLEUM PROD113 citations96
US4679639AJul 14, 1987
Rotary drill bits and cutting elements for such bits
NL PETROLEUM PROD73 citations95
US4624830ANov 25, 1986
Manufacture of rotary drill bits
NL PETROLEUM PROD35 citations93
US4577706AMar 25, 1986
Rotary drill bits
NL PETROLEUM PROD35 citations93
US4733735AMar 29, 1988
Rotary drill bits
NL PETROLEUM PROD43 citations92
US4697654AOct 6, 1987
Rotary drill bits
NL PETROLEUM PROD10 citations74
CAMCO DRILLING GROUP LTD
6 patentsUS5706905AJan 13, 1998
Steerable rotary drilling systems
CAMCO DRILLING GROUP LTD416 citations99
US5582259ADec 10, 1996
Modulated bias unit for rotary drilling
CAMCO DRILLING GROUP LTD219 citations99
US5265682ANov 30, 1993
Steerable rotary drilling systems
CAMCO DRILLING GROUP LTD416 citations99
US5803185ASep 8, 1998
Steerable rotary drilling systems and method of operating such systems
CAMCO DRILLING GROUP LTD277 citations98
US5520255AMay 28, 1996
Modulated bias unit for rotary drilling
CAMCO DRILLING GROUP LTD329 citations97
US5165494ANov 24, 1992
Rotary drills bits
CAMCO DRILLING GROUP LTD51 citations96
REED TOOL CO
6 patentsUS4995887AFeb 26, 1991
Cutting elements for rotary drill bits
REED TOOL CO30 citations92
US4942933AJul 24, 1990
Relating to rotary drill bits
REED TOOL CO52 citations92
US4873895AOct 17, 1989
Manufacture of rotary drill bits
REED TOOL CO20 citations78
US5101691AApr 7, 1992
Methods of manufacturing cutter assemblies for rotary drill bits
REED TOOL CO8 citations74
US4898252AFeb 6, 1990
Cutting structures for rotary drill bits
REED TOOL CO14 citations74
US4878403ANov 7, 1989
Manufacture of rotary drill bits
REED TOOL CO7 citations74