Subsea wellhead system
US4597448A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 30, 1983 |
| Grant date | Jul 1, 1986 |
| Priority date | — |
| Expiry date | Nov 30, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S285/917
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The subsea wellhead system includes a wellhead, a housing seat disposed in and connected to the wellhead, a casing hanger supported by the seat, a holddown and sealing assembly in the annulus between wellhead and hanger, a running tool attached to the hanger for lowering it into the well and initially actuating the holddown and sealing assembly, and apparatus for applying hydraulic pressure to further actuate the seal. The housing seat and wellhead are connected by breech block teeth. The seat maintains 360.degree. bearing surface with the hanger. The holddown and seal assembly includes an upper rotating member threadingly engaging the hanger and suspending a lower stationary member. The latter includes a Z-shaped portion having a plurality of frustoconical metal rings positively connected by links. The rings form grooves housing resilient elastomeric members. Upon compression of the Z-shaped portion, the elastomeric members initially sealingly engage the wellhead and hanger and then, upon further compression, the rings deform into metal-to-metal engagement with the wellhead and hanger forming a primary seal. The seal is actuated initially by torque applied through a running tool c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.