Flexible joint for downhole tools
US5836388A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 16, 1997 |
| Grant date | Nov 17, 1998 |
| Priority date | — |
| Expiry date | Jul 16, 2017 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/02
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A downhole measurement tool is lowered into a well through a drill pipe. The tool has at least two modules which are joined by a flexible linkage. The linkage has two subs, each of which has an electrical connector for the modules. Each sub has a hub that is threaded. A threaded retainer nut retains each connector. Each nut has a hub that is threaded and is smaller in diameter than the sub hub. A coiled inner spring threadingly engages each nut hub. A coiled outer spring surrounds and threadingly engages each sub hub. The outer spring surrounds the inner spring and is wound in an opposite direction of the inner spring. The springs are embedded within an elastomeric member. The inner spring is dimensioned such that, for a selected lateral bend prior to installation with the outer spring, the inner spring will twist a selected angle in a first twist direction. Similarly, the outer spring is dimensioned such that for the selected lateral bend, prior to installation with the inner spring, the outer spring will twist substantially the same as the selected angle, but in a direction opposite to the first twist direction so as to cancel any twist between the subs once installed and subject…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.