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:
Nov. 11, 1986
Filed:
Mar. 04, 1985
Joseph R Roche, Houston, TX (US);
Hydril Company, Los Angeles, CA (US);
Abstract
A marine riser safety valve is disclosed which, when placed in series with a deep water marine riser string, prevents collapse of riser pipe when inadvertent gas influx replaces the drilling fluid column. A cylindrical body is provided having a depression formed therein with at least one diaphragm port from the central bore of the body through the wall of the depression. A valve port is provided axially from the depression. A cylindrical member including a cylindrical diaphragm and a valve sleeve are joined end-to-end. The cylindrical member is disposed about the exterior of the body with the elastomeric diaphragm covering the depression and the valve sleeve covering the valve port. When a differential pressure develops across the wall of the diaphragm of a predetermined threshold, the diaphragm constricts into the body depression and moves the valve sleeve axially, opening the valve port to permit sea water influx. An outer skirt is provided to prevent outward ballooning of the diaphragm when bore pressure is greater than the surrounding sea water pressure.