Torque-dependent oscillation of a dual-pipe inner pipe section
US11053756B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 2019 |
| Grant date | Jul 6, 2021 |
| Priority date | — |
| Expiry date | Aug 15, 2039 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B7/046
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for building a dual-member drill string comprising an inner drill string and an outer drill string. Inner pipe sections are connected using non-threaded connections, while outer pipe sections are connected using threaded connections. A new inner pipe section is rotated in a first direction until the inner pipe section applies torque to the existing inner pipe string. If the magnitude of the torque applied to the inner pipe string exceeds a pre-determined threshold value, the inner pipe section is automatically rotated in an opposite second direction. The inner pipe section rotates between opposite directions, once torque is sensed in each direction, until the inner pipe section is coupled to the inner pipe string.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.