Centering apparatus
US4595055A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 8, 1984 |
| Grant date | Jun 17, 1986 |
| Priority date | — |
| Expiry date | May 8, 2004 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/1021
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A device for centering a tool forming a part of a tool string, inside a cased well, comprises a central bar suitable for being integrated in a tool string for lowering the tool inside the tubing, two slides which are slidable over a limited range of said central bar, and a series of wheel-carrying structures of generally triangular geometry defined by arms which are hinged to said slides. The device further comprises a series of wheels with each wheel being mounted to rotate freely on a respective one of said wheel-carrying structures in a plane which is inclined relative to a radial plane through the wheel-carrying structure in such a manner that its periphery projects radially outwardly. When the wheel-carrying structures are fully retracted against the central bar, the wheels are received in recesses provided in the outer surface of the central bar. Resilient return means are provided to urge the wheels radially outwardly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.