Apparatus and method to reduce fluid pressure in a wellbore
US7395877B2 · kind B2 · utility
9Cited by
41References
13Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 26, 2006 |
| Grant date | Jul 8, 2008 |
| Priority date | — |
| Expiry date | Sep 26, 2026 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B21/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
The present invention generally provides apparatus and methods for reducing the pressure of a circulating fluid in a wellbore. In one aspect of the invention an ECD (equivalent circulation density) reduction tool provides a means for drilling extended reach deep (ERD) wells with heavyweight drilling fluids by minimizing the effect of friction head on bottomhole pressure so that circulating density of the fluid is close to its actual density. With an ECD reduction tool located in the upper section of the well, the friction head is substantially reduced, which substantially reduces chances of fracturing a formation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.