Method for drilling deviated wellbores
US4573540A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 19, 1984 |
| Grant date | Mar 4, 1986 |
| Priority date | — |
| Expiry date | Nov 19, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/10
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Directional drilling of a high-angle wellbore is carried out by the drilling of a vertical first portion to a kick-off point at which a high-angle, deviated second portion is initiated. The wellbore is cased to at least below the kick-off point. A casing liner is lowered through the wellbore so that it extends coextensively with the casing. The liner is spaced from the casing by a casing hanger positioned above the kick-off point. The liner is sealed in the casing and prevented from rotating during drilling by a packer bore receptacle positioned between the lower end of the liner and the casing. During the drilling of the deviated second portion of the wellbore, the casing liner protects the casing from wear due to the rotation of the drill string as it lies on the lower side of the high-angle wellbore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.