Wellhead
US6571877B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 17, 1998 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Jun 17, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B2200/01
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
In the drilling of a well, a dedicated drilling wellhead (520) mounted at the top of the casing cluster whilst the well is being drilled. At the end of drilling, a seal ring or sleeve (534) which during the drilling phase has the function of an annular sleeve isolating the well bore pressure from the production annulus space (540), is manipulated into an alternative position in which it acts to block the annular space (540) thereby acting as a temporary abandonment seal. A further plug seal is fitted in the well bore. The well is now temporarily sealed and the drilling wellhead can then be removed and can be reused on another well during the drilling phase of that well. A production wellhead (550,556) which has a cantilever christmas tree fitted on its side over a production wellhead (557) which can accept a conventional christmas tree on top is then fitted on to the casing hanger cluster. Prior to installation of the tubing hanger the seal ring sleeve (534) can be manipulated back into its upper position from where it seals the production annulus (540) from the well bore while allowing monitoring of the production annulus (540) through the outlet port (542).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.