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:
Sep. 22, 1987
Filed:
May. 23, 1986
Robert A Cunningham, Bellaire, TX (US);
Hughes Tool Company - USA, Houston, TX (US);
Abstract
An inside blowout preventer for use in an earth boring drill string has features to reduce erosion. The blowout preventer has a valve body for connection into the drill string with a longitudinal passage extending through the body. The ball seat is located in the longitudinal passage. A ball storage location is located below the seat, and offset from the longitudinal passage. A ball is carried in the storage location during downward flow, and moves into the longitudinal passage to seat against the seat if the upward flow is sufficient. The storage location is located in an area of the longitudinal passage which has a much larger flow area than through the seat. The downward flow impinges on a portion of the ball. A communication passage extends from the storage location downward to a reduced diameter section of the longitudinal passage.