Patent · US Expired

Surface wellhead

US4938289A · kind A · utility

34Cited by
4References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 21, 1988
Grant dateJul 3, 1990
Priority date
Expiry dateNov 21, 2008

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B33/04
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A casing installation system usable with tubular casing having an upper end portion and a lower portion, for anchoring the upper end portion of the casing on an outer casing string secured to a wellhead having a housing, the wellhead housing being positioned at a fixed position over a well, said casing extending upwardly to the wellhead from a location in the well at which location the lower portion of the casing is landed, the upper end of the casing being terminated by a generally annular casing hanger secured to the casing, said outer casing string having an upwardly-facing shoulder, the system also having a locking ring located on the casing hanger and movable thereon in a direction towards the lower end portion of the casing, the locking ring having means for preventing its movement on the casing in a direction away from the lower end portion of the casing in response to a force exerted on the locking ring in said direction away from the lower end of the casing, the locking ring having a downwardly-facing shoulder engageable with the upwardly-facing shoulder on the outer casing string.

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