Apparatus for measuring weight, torque and side force on a drill bit
US4958517A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 7, 1989 |
| Grant date | Sep 25, 1990 |
| Priority date | — |
| Expiry date | Aug 7, 2009 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B47/007
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
Apparatus is presented for measuring weight, torque and side force (bending) on a drill bit for oil and gas well drilling. This apparatus includes radial holes which do not pass completely through the wall of the drill collar sub, but instead, pass only partially through the wall of the drill collar sub. Strain gages are located in the partial radial openings. These strain gages measure each of the three parameters of weight, torque and bending. Each partially formed hole is sealed by a plug and retained in place by a retaining ring. For torque and bending measurements, the strain gages are arranged with symmetry of position between diametrically opposed holes. The strain gages are positioned in an array which departs from symmetry of position to minimize errors in the weight measurement caused by pressure changes in the drilling fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.