Adjustable flexibility anchor device with retractable arms for well tools
US5769163A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 13, 1996 |
| Grant date | Jun 23, 1998 |
| Priority date | — |
| Expiry date | May 13, 2016 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B23/042
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An elastic force generated by a volume of compressed gas in a chamber (7b) of a cavity (7) interior to the body of a well tool (1), acting on a piston (8), is used to open arms (4) intended to anchor the tool to the wall of a well (2). In order to close them, an opposed hydraulic force generated by a pump (13) driven by an electric motor (14) is applied intermittently, which brings piston (8) back to a recoil position. Piston (8) is coupled hydraulically with the cylinders of jacks (5, 6) acting on arms (4). A sufficient elastic force can thus be generated under a very low volume and the characteristics thereof can be readily changed by acting on the gas injection pressure and/or the extent of the dead volume when piston (8) is in a recoil position. Such device can be used for coupling sondes in wellbores for seismic prospecting for example.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.