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. 19, 1996
Filed:
Sep. 01, 1995
Melvyn F Whitby, Houston, TX (US);
Frank L Sklenka, Kingwood, TX (US);
David L O'Donnell, Houston, TX (US);
Varco Shaffer, Inc., Houston, TX (US);
Abstract
A hydraulically controlled ram actuating mechanism 10 for a blowout preventer controls the opening and closing of a ram block 12 interconnected with a ram 14 movable within a ram housing 26 along ram axis 16. The ram piston 24 and a locking piston 62 are each movable within the ram housing in response to fluid pressure. The locking piston includes a plurality of substantially planar tapered locking piston surfaces 72 circumferentially arranged on the exterior of the locking piston and inclined at an acute positive cam angle. A plurality of locking rods 40 are each secured to the ram housing 26 and are circumferentially spaced about the locking piston, with each locking rod including a substantially planar tapered locking rod surface 82 thereon inclined at an acute negative cam angle. A plurality of locking segments 60 are each spaced radially between a locking rod and the locking piston, with each locking segment adapted for being sandwiched between the locking surfaces for preventing opening of the ram until the locking piston is moved in response to fluid pressure. The actuating mechanism reliably controls the flow of well fluids through the blowout preventer and may be automatically locked in an infinite number of locking positions within a wide locking range.