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:
Feb. 28, 1989
Filed:
Sep. 11, 1987
Herman O Henderson, Aberdeen, GB;
Joseph H Hynes, Houston, TX (US);
Cameron Iron Works USA, Inc., Houston, TX (US);
Abstract
A subsea wellhead housing for an underwater well has a small, integral landing shoulder in the bore for supporting an intermediate casing string. The small landing shoulder permits passage of a standard 171/2 inch drill bit. Breech block teeth are provided in the wellhead housing bore above the small landing shoulder for attaching a separately installable landing shoulder insert. The breech block teeth also permit passage of a standard 171/2 inch drill bit. An intermediate casing hanger is landed on the small, integral shoulder, and the landing shoulder insert installed in the wellhead housing. The landing shoulder insert has a skirt at its lower end which is received in and sealed against the upper end of the hanger. The upper end of the landing shoulder insert is sealed against the wellhead housing bore. In one embodiment, the hanger for 17 inch casing is fluted on its outer surface to pass through breech block slots in the wellhead housing bore in order to reach its landing shoulder. In another embodiment, the breech block profile is bored out to allow passage therethrough of a 16 inch casing hanger to reach its landing shoulder without rotationally orienting the hanger with respect to the wellhead. In all embodiments, pressure end load from internal wellhead pressure is transferred to the housing by the breech block teeth between the housing and the landing shoulder insert. The small, integral landing shoulder thereby supports only the intermediate casing string weight.