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:
Dec. 28, 1976
Filed:
Nov. 25, 1974
Applicant:
Inventor:
Joseph Ott, Lacq, F;
Assignee:
Societe Nationale des Petroles d'Aquitaine, Courbevoie, F;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21B / ;
U.S. Cl.
CPC ...
137629 ; 166 72 ; 166324 ;
Abstract
A hydraulic safety stop-valve fitted with hermetic sealing means. The equalization passage between pressures above and below the stop-valve comprises two means of sealing, one provided by contact between two truncated conical bearing surfaces on the outer casing and inner tube, and the other consisting of valves, held by springs against the equalization passage inlet apertures, bored in the lower tubular element of the outer casing, and the opening of which is controlled by a truncated conical surface on the inner tube. This device ensures a high level of safety in stop-valves used in large production tubings for wells at sea.