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:
Jan. 19, 1988
Filed:
Nov. 29, 1985
Joseph R Roche, Humble, TX (US);
Gabriel G Alexander, Houston, TX (US);
Hydril Company, Los Angeles, CA (US);
Abstract
A marine riser anticollapse valve is disclosed for preventing a marine riser from collapsing under external sea water pressure in the event of a sudden loss of internal drilling fluid pressure. An external valve structure is provided for each of a plurality of openings in the wall of a riser pup joint. Each of the valve structures includes a cylinder having an opening in communication with a body wall opening. A piston in each cylinder is subject to sea water pressure but is prevented from opening when riser bore pressure of a sufficient magnitude is applied internally to the piston via the pup joint opening and cylinder opening. When the riser bore pressure falls, the piston is driven to an open position allowing sea water to enter the riser.