Assignee
NAT OILWELL LP
US41 patents
Top patents by PatentIndex Score
US7249639B2Jul 31, 2007
Automated arm for positioning of drilling tools such as an iron roughneck
NAT OILWELL LP68 citations98
US7178612B2Feb 20, 2007
Automated arm for positioning of drilling tools such as an iron roughneck
NAT OILWELL LP90 citations98
US7000502B2Feb 21, 2006
Drillpipe spinner
NAT OILWELL LP56 citations96
US6634436B1Oct 21, 2003
Mobile land drilling apparatus and method
NAT OILWELL LP117 citations96
US7231981B2Jun 19, 2007
Inline compensator for a floating drill rig
NAT OILWELL LP61 citations95
US7455128B2Nov 25, 2008
Automated arm for positioning of drilling tools such as an iron roughneck
NAT OILWELL LP33 citations92
US6971283B2Dec 6, 2005
Jaw insert for gripping a cylindrical member and method of manufacture
NAT OILWELL LP49 citations92
US7765749B2Aug 3, 2010
Fast moving drilling rig
NAT OILWELL LP62 citations91
US7121166B2Oct 17, 2006
Power tong assembly
NAT OILWELL LP48 citations90
US6910402B2Jun 28, 2005
Pipe spinner
NAT OILWELL LP28 citations90
US7293607B2Nov 13, 2007
Automated system for positioning and supporting the work platform of a mobile workover and well-servicing rig
NAT OILWELL LP30 citations89
US7246983B2Jul 24, 2007
Pipe racking system
NAT OILWELL LP62 citations87
US6681858B2Jan 27, 2004
Packer retriever
NAT OILWELL LP25 citations87
US6588318B2Jul 8, 2003
Hydraulic retention system for reciprocating pump cylinder liner
NAT OILWELL LP20 citations87
US6182945B1Feb 6, 2001
Redundant drawworks
NAT OILWELL LP42 citations87
US6386516B1May 14, 2002
Sheave block with retractable sheave guards
NAT OILWELL LP48 citations86
US5960700AOct 5, 1999
Replaceable mud pump piston seal
NAT OILWELL LP45 citations86
US7185881B2Mar 6, 2007
Electric winch
NAT OILWELL LP38 citations85
US7040411B2May 9, 2006
BOP handling system
NAT OILWELL LP42 citations85
US6536467B2Mar 25, 2003
Valve with increased inlet flow
NAT OILWELL LP21 citations85
US7132127B2Nov 7, 2006
Centrifugal applicator
NAT OILWELL LP12 citations84
US7228919B2Jun 12, 2007
Pivoting pipe handler for off-line make up of drill pipe joints
NAT OILWELL LP45 citations83
US6923254B2Aug 2, 2005
Washpipe apparatus
NAT OILWELL LP38 citations83
US6227240B1May 8, 2001
Unitized spherical profile check valve with replaceable sealing element
NAT OILWELL LP30 citations83
US7546869B2Jun 16, 2009
Automated system for positioning and supporting the work platform of a mobile workover and well-servicing rig
NAT OILWELL LP8 citations80
US8006751B2Aug 30, 2011
Automated system for positioning and supporting the work platform of a mobile workover and well-servicing rig
NAT OILWELL LP16 citations79
US7523694B2Apr 28, 2009
Cylinder liner preload system
NAT OILWELL LP9 citations79
US7234896B2Jun 26, 2007
Vertically folding service arm for a movable platform offshore drilling or servicing rig
NAT OILWELL LP14 citations79
US7155873B2Jan 2, 2007
Structural connector for a drilling rig substructure
NAT OILWELL LP16 citations77
US7066251B2Jun 27, 2006
Hydraulic jar lock
NAT OILWELL LP11 citations76
US6554523B2Apr 29, 2003
Hydraulic rod connector system
NAT OILWELL LP16 citations74
US7111676B2Sep 26, 2006
Pipe centering device
NAT OILWELL LP7 citations71
US5599497AFeb 4, 1997
Alloy steel roll caster shell
NAT OILWELL LP16 citations71
US7296640B2Nov 20, 2007
Solids control system
NAT OILWELL LP14 citations70
US6571667B2Jun 3, 2003
Manual tong safety latch
NAT OILWELL LP15 citations70
US7293618B2Nov 13, 2007
Power slip for drillpipe
NAT OILWELL LP10 citations69
US7461700B2Dec 9, 2008
Apparatus and method for a C-plate used in a cable guided fishing assembly
NAT OILWELL LP7 citations67
US6327940B1Dec 11, 2001
Multi-piece manual tong safety handle
NAT OILWELL LP9 citations58
US7828533B2Nov 9, 2010
Positive displacement motor/progressive cavity pump
NAT OILWELL LP5 citations46
US7137586B2Nov 21, 2006
Hydraulic spooler
NAT OILWELL LP6 citations46
US7345396B2Mar 18, 2008
Metallic laminations for magnetic circuits
NAT OILWELL LP3 citations45