Well completion device and method of cementing
US5791416A · kind A · utility
Inventors
Key dates
| Filing date | Jul 12, 1996 |
| Grant date | Aug 11, 1998 |
| Priority date | — |
| Expiry date | Jul 12, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B33/14
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method of cementing a production casing in a borehole having a surface casing therein wherein cement is pumped down through the production casing thereby cementing the production casing into the borehole and the surface casing. Prior to pumping a special production casing section carrying a tubular expandable resilient bladder is installed in the production casing. The bladder has flanges at either end and slots passing through the flanges. The bladder has an internal thread at one end which mates with an external thread on the casing section thereby anchoring the bladder. The other end of the bladder is free. When installed there is clearance between the bladder and the surrounding surface casing. This permits the bladder to expand upwardly when cement is pumped through and when there is a sufficient head of cement after pumping the bladder collapses and provides a good seal between the production casing section and the surface casing section.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.