Tong
US6330911A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 12, 1999 |
| Grant date | Dec 18, 2001 |
| Priority date | — |
| Expiry date | Mar 12, 2019 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B19/164
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A tong for rotating tubulars, the tong having, in certain embodiments, a tong outer case, a rotary movably mounted in the case for rotating a tubular, apparatus for rotating the rotary to rotate the tubular, at least one gripper or jaw movably mounted in the case and movable by the rotary for gripping the tubular, the at least one gripper or jaw having at least one cam following member or roller, and at least one non-circular cam surface on the rotary, the at least one cam following member or roller contacting and movable on the at least one non-circular cam surface for maintaining a desired position of the at least one gripper or jaw with respect to the tubular. In certain embodiments a specific cam angle, within certain tolerances, is maintained substantially the entire length along a cam surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.