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:
Aug. 26, 1997
Filed:
Feb. 01, 1996
Paul A Hebert, Houston, TX (US);
Lionel J Milberger, Houston, TX (US);
Joseph W Pallini, Jr, Tomball, TX (US);
ABB Vetco Gray Inc., Houston, TX (US);
Chevron Corporation, San Francisco, CA (US);
Abstract
A subsea wellhead system is used in areas which have shallow water producing sands. A first string of casing extends from the sea floor through a section of conductor pipe and below the conductor pipe to a point above the water sand. An external wellhead housing having flow ports is supported at the upper end of the conductor pipe. A valve sleeve is located on the exterior of the external wellhead housing. The valve sleeve is movable to a closed position, closing the flow ports. A second string of casing is installed to a point below the water producing formation. An internal wellhead housing is secured to the upper end of the second string of casing, which lands within the external wellhead housing. During cementing of the second string of casing the flow ports are open. After cementing, the valve sleeve is moved to the closed position.