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Referenced by

Citing PatentFiling dateIssue dateOriginal AssigneeTitle
US397014713 Jan 197520 Jul 1976Halliburton CompanyMethod and apparatus for annulus pressure responsive circulation and tester valve manipulation
US404482919 Jul 197630 Aug 1977Halliburton CompanyMethod and apparatus for annulus pressure responsive circulation and tester valve manipulation
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US46257557 Aug 19842 Dec 1986Kelly mud saver valve sub
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US488005816 May 198814 Nov 1989Lindsey Completion Systems, Inc.Stage cementing valve
US58652613 Mar 19972 Feb 1999Baker Hughes IncorporatedBalanced or underbalanced drilling method and apparatus
US62538535 Oct 19983 Jul 2001Stellarton Energy CorporationFluid injection tubing assembly and method
US81670516 Jul 20071 May 2012National Oilwell Varco, L.P.Selective agitation