The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 30, 1977
Filed:
Jul. 19, 1976
Applicant:
Inventors:
Robert L Jessup, Duncan, OK (US);
Joe E Coleman, New Orleans, LA (US);
Assignee:
Halliburton Company, Duncan, OK (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ; E21B / ;
U.S. Cl.
CPC ...
166264 ; 166315 ; 166323 ;
Abstract
A releasably locked closed circulation valve is introduced into a well bore as part of a drill string. The annulus between the drill string and the well bore, or casing affixed to the well bore, is sealed. Pressure is applied to the annulus and the valve unlocks and opens once the annulus pressure reaches a certain level to allow circulation between the annulus and the interior of the drill string. An optional locking device preferably locks the opened valve in the open position. A second embodiment includes a tester valve simultaneously operable with the circulation valve.