Patent · US Expired

Surface wellhead

US4794988A · kind A · utility

26Cited by
2References
10Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 22, 1987
Grant dateJan 3, 1989
Priority date
Expiry dateJun 22, 2007

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B33/043
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Surface wellhead apparatus for use in tying-back casing from a subsea structure to a surface structure or when drilling with mudline-supported casing hangers wherein the casing is maintained in tension by means of a lock member which releasably engages with a support surface, the lock member and support surface being, on release, relatively movable in a direction longitudinal of the casing and, on engagement, locked against downward movement of the casing.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.