Convertible jack
US7117948B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jun 28, 2004 |
| Grant date | Oct 10, 2006 |
| Priority date | — |
| Expiry date | May 26, 2025 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/00
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A snubbing unit for running and retrieving a string of tubing into a well under pressure selectively operates in a stand alone mode and a rig assist mode. The unit has a lower frame for mounting during the stand alone mode on a snubber blowout preventer. Stationary weight supporting slips and snubbing slips are carried by the lower frame during the stand alone mode. The unit has four hydraulic cylinders with weight supporting slips and snubbing slips carried by a traveling base plate on the piston rods. A stationary base plate is mounted between the lower frame and the traveling base plate. A spacer tube is connected to and between the lower frame and the stationary base plate in the stand alone mode. In the rig assist mode, the lower frame along with the stationary weight supporting slips and the spacer tube are removed to enable a rig blowout preventer to connect to the stationary base plate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.