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:
Apr. 09, 1996
Filed:
Apr. 05, 1995
Applicant:
Inventors:
Assignee:
Varco Shaffer, Inc., Houston, TX (US);
Primary Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
251-13 ; 251-11 ;
Abstract
A hydraulically controlled blowout preventer 10 and method are disclosed for simultaneously moving two sealing assemblies 24, 27 to seal around an oilfield tubular 15 within the bore 14 of BOP 10. A single manual operator 20 may be rotated to simultaneously move master piston 26 and hydraulically interconnected slave piston 79 inwardly toward bore 14 or outwardly away from bore 14, respectively. BOP 10 is field convertible to purely hydraulic operation by disconnecting the threaded shaft 52 from master piston 26. Hydraulic lines 36 and 40 interconnect between cylinders 30 and 82 to result in simultaneous operation of seal assemblies 24, 27.