|
| US3964544 | 20 Jun 1975 | 22 Jun 1976 | Halliburton Company | Pressure operated isolation valve for use in a well testing and treating apparatus, and its method of operation |
| US3976136 | 20 Jun 1975 | 24 Ago 1976 | Halliburton Company | Pressure operated isolation valve for use in a well testing apparatus and its method of operation |
| US4047564 | 14 Jul 1975 | 13 Sep 1977 | Halliburton Company | Weight and pressure operated well testing apparatus and its method of operation |
| US4059153 | 2 Dic 1976 | 22 Nov 1977 | Halliburton Company | Weight and pressure operated well testing apparatus and its method of operation |
| US4063593 | 16 Feb 1977 | 20 Dic 1977 | Halliburton Company | Full-opening annulus pressure operated sampler valve with reverse circulation valve |
| US4064937 | 16 Feb 1977 | 27 Dic 1977 | Halliburton Company | Annulus pressure operated closure valve with reverse circulation valve |
| US4076077 | 2 Dic 1976 | 28 Feb 1978 | Halliburton Company | Weight and pressure operated well testing apparatus and its method of operation |
| US4083409 | 2 May 1977 | 11 Abr 1978 | Halliburton Company | Full flow bypass valve |
| US4105075 | 21 Jul 1977 | 8 Ago 1978 | Baker International Corporation | Test valve having automatic bypass for formation pressure |
| US4109724 | 27 Oct 1977 | 29 Ago 1978 | Halliburton Company | Oil well testing valve with liquid spring |
| US4109725 | 27 Oct 1977 | 29 Ago 1978 | Halliburton Company | Self adjusting liquid spring operating apparatus and method for use in an oil well valve |
| US4113012 | 27 Oct 1977 | 12 Sep 1978 | Halliburton Company | Reclosable circulation valve for use in oil well testing |
| US4125165 | 21 Jul 1977 | 14 Nov 1978 | Baker International Corporation | Annulus pressure controlled test valve with locking annulus pressure operated pressure trapping means |
| US4129184 | 27 Jun 1977 | 12 Dic 1978 | Del Norte Technology, Inc. | Downhole valve which may be installed or removed by a wireline running tool |
| US4144937 | 19 Dic 1977 | 20 Mar 1979 | Halliburton Company | Valve closing method and apparatus for use with an oil well valve |
| US4253525 | 31 Jul 1978 | 3 Mar 1981 | Schlumberger Technology Corporation | Retainer valve system |
| US4295361 | 3 Abr 1980 | 20 Oct 1981 | Halliburton Company | Drill pipe tester with automatic fill-up |
| US4399870 | 22 Oct 1981 | 23 Ago 1983 | Hughes Tool Company | Annulus operated test valve |
| US4420045 | 3 May 1982 | 13 Dic 1983 | Halliburton Company | Drill pipe tester and safety valve |
| US4421172 | 13 Jul 1981 | 20 Dic 1983 | Halliburton Company | Drill pipe tester and safety valve |
| US4422506 | 5 Nov 1980 | 27 Dic 1983 | Halliburton Company | Low pressure responsive APR tester valve |
| US4429748 | 24 Mar 1982 | 7 Feb 1984 | Halliburton Company | Low pressure responsive APR tester valve |
| US4444268 | 4 Mar 1982 | 24 Abr 1984 | Halliburton Company | Tester valve with silicone liquid spring |
| US4445571 | 20 Ago 1981 | 1 May 1984 | Halliburton Company | Circulation valve |
| US4448254 | 14 Sep 1982 | 15 May 1984 | Halliburton Company | Tester valve with silicone liquid spring |
| US4452313 | 21 Abr 1982 | 5 Jun 1984 | Halliburton Company | Circulation valve |
| US4489786 | 19 Sep 1983 | 25 Dic 1984 | Halliburton Company | Low pressure responsive downhole tool with differential pressure holding means |
| US4515219 | 19 Sep 1983 | 7 May 1985 | Halliburton Company | Low pressure responsive downhole tool with floating shoe retarding means |
| US4522266 | 5 Mar 1982 | 11 Jun 1985 | Halliburton Company | Downhole tester valve with resilient seals |
| US4537258 | 19 Sep 1983 | 27 Ago 1985 | Halliburton Company | Low pressure responsive downhole tool |
| US4553598 | 24 Sep 1984 | 19 Nov 1985 | Schlumberger Technology Corporation | Full bore sampler valve apparatus |
| US4557333 | 19 Sep 1983 | 10 Dic 1985 | Halliburton Company | Low pressure responsive downhole tool with cam actuated relief valve |
| US4560004 | 30 May 1984 | 24 Dic 1985 | Halliburton Company | Drill pipe tester - pressure balanced |
| US4577692 | 4 Mar 1985 | 25 Mar 1986 | Hughes Tool Company | Pressure operated test valve |
| US4589485 | 31 Oct 1984 | 20 May 1986 | Halliburton Company | Downhole tool utilizing well fluid compression |
| US4595060 | 28 Nov 1984 | 17 Jun 1986 | Halliburton Company | Downhole tool with compressible well fluid chamber |
| US4617999 | 28 Nov 1984 | 21 Oct 1986 | Halliburton Company | Downhole tool with compression chamber |
| US4633952 | 3 Abr 1984 | 6 Ene 1987 | Halliburton Company | Multi-mode testing tool and method of use |
| US4646838 | 12 Dic 1985 | 3 Mar 1987 | Halliburton Company | Low pressure responsive tester valve with spring retaining means |
| US4655288 | 3 Jul 1985 | 7 Abr 1987 | Halliburton Company | Lost-motion valve actuator |
| US4657083 | 12 Nov 1985 | 14 Abr 1987 | Halliburton Company | Pressure operated circulating valve with releasable safety and method for operating the same |
| US4664196 | 28 Oct 1985 | 12 May 1987 | Halliburton Company | Downhole tool with compressible liquid spring chamber |
| US4665991 | 28 Ene 1986 | 19 May 1987 | Halliburton Company | Downhole tool with gas energized compressible liquid spring |
| US4691779 | 17 Ene 1986 | 8 Sep 1987 | Halliburton Company | Hydrostatic referenced safety-circulating valve |
| US4711305 | 31 Dic 1986 | 8 Dic 1987 | Halliburton Company | Multi-mode testing tool and method of testing |
| US4736798 | 16 May 1986 | 12 Abr 1988 | Halliburton Company | Rapid cycle annulus pressure responsive tester valve |
| US4753292 | 3 Jul 1985 | 28 Jun 1988 | Halliburton Company | Method of well testing |
| US4907655 | 6 Abr 1988 | 13 Mar 1990 | Schlumberger Technology Corporation | Pressure-controlled well tester operated by one or more selected actuating pressures |
| US4911242 | 16 Oct 1989 | 27 Mar 1990 | Schlumberger Technology Corporation | Pressure-controlled well tester operated by one or more selected actuating pressures |
| US4979568 | 16 Ene 1990 | 25 Dic 1990 | Baker Hughes Incorporated | Annulus fluid pressure operated testing valve |
| US5050681 | 10 Jul 1990 | 24 Sep 1991 | Halliburton Company | Hydraulic system for electronically controlled pressure activated downhole testing tool |
| US5101907 | 20 Feb 1991 | 7 Abr 1992 | Halliburton Company | Differential actuating system for downhole tools |
| US5127477 | 20 Feb 1991 | 7 Jul 1992 | Halliburton Company | Rechargeable hydraulic power source for actuating downhole tool |
| US5156207 | 10 May 1991 | 20 Oct 1992 | Halliburton Company | Hydraulically actuated downhole valve apparatus |
| US5238070 | 19 Feb 1992 | 24 Ago 1993 | Halliburton Company | Differential actuating system for downhole tools |
| US5251703 | 2 Jul 1992 | 12 Oct 1993 | Halliburton Company | Hydraulic system for electronically controlled downhole testing tool |
| US5265679 | 13 Mar 1992 | 30 Nov 1993 | Baker Hughes Incorporated | Equalizing apparatus for use with wireline-conveyable pumps |
| US5273112 | 18 Dic 1992 | 28 Dic 1993 | Halliburton Company | Surface control of well annulus pressure |
| US5318130 | 11 Ago 1992 | 7 Jun 1994 | Halliburton Company | Selective downhole operating system and method |
| US5353870 | 28 May 1993 | 11 Oct 1994 | | Well purging and sampling pump |
| US5355960 | 18 Dic 1992 | 18 Oct 1994 | Halliburton Company | Pressure change signals for remote control of downhole tools |
| US5412568 | 18 Dic 1992 | 2 May 1995 | Halliburton Company | Remote programming of a downhole tool |
| US5482119 | 30 Sep 1994 | 9 Ene 1996 | Halliburton Company | Multi-mode well tool with hydraulic bypass assembly |
| US5490564 | 19 Ago 1994 | 13 Feb 1996 | Halliburton Company | Pressure change signals for remote control of downhole tools |
| US5577560 | 12 Jul 1993 | 26 Nov 1996 | Baker Hughes Incorporated | Fluid-actuated wellbore tool system |
| US5887657 | 14 Mar 1997 | 30 Mar 1999 | Baker Hughes Incorporated | Pressure test method for permanent downhole wells and apparatus therefore |
| US5934371 | 25 Jun 1998 | 10 Ago 1999 | Baker Hughes Incorporated | Pressure test method for permanent downhole wells and apparatus therefore |
| US5992520 | 15 Sep 1997 | 30 Nov 1999 | Halliburton Energy Services, Inc. | Annulus pressure operated downhole choke and associated methods |
| US6073698 | 10 Ago 1999 | 13 Jun 2000 | Halliburton Energy Services, Inc. | Annulus pressure operated downhole choke and associated methods |
| US7004638 | 6 Dic 2002 | 28 Feb 2006 | Diamould Limited | Sealing system for connector |
| US7124824 | 12 Feb 2003 | 24 Oct 2006 | BJ Services Company, U.S.A. | Washpipeless isolation strings and methods for isolation |
| US7152678 | 27 Feb 2004 | 26 Dic 2006 | BJ Services Company, U.S.A. | System and method for downhole operation using pressure activated valve and sliding sleeve |
| US7198109 | 12 Feb 2003 | 3 Abr 2007 | BJ Services Company | Double-pin radial flow valve |
| US7201232 | 13 Nov 2003 | 10 Abr 2007 | BJ Services Company | Washpipeless isolation strings and methods for isolation with object holding service tool |
| US7637317 | 5 Oct 2007 | 29 Dic 2009 | | Frac gate and well completion methods |
| US7665526 | 21 Dic 2006 | 23 Feb 2010 | BJ Services Company, U.S.A. | System and method for downhole operation using pressure activated and sleeve valve assembly |
| USRE40648 | 26 Feb 2007 | 10 Mar 2009 | BJ Services Company, U.S.A. | System and method for downhole operation using pressure activated valve and sliding sleeve |
