One-trip casing cutting & removal apparatus
US6357528B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 2000 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Mar 30, 2020 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B31/20
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A one-trip system for removing casing from a wellhead is described. The string includes a cutting device spaced at the required depth and a grappling device above it at the appropriate location. A swivel tool, such as a marine swivel, is used in conjunction with a seal-pulling assembly so that after cutting the casing, the seal assembly can be pulled without an additional trip into the well. The grappling device or spear can be hydraulically actuated to grab the casing for removal from the wellbore. The spear features a drop-in restrictor which allows sufficient flow during cutting operations with a mechanical cutter without actuating the spear, while at the same time allowing actuation of the spear by circulation after dropping in the restrictor after the casing section has been cut.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.