| 摘要 |
<p>A backup tong (1) having an inner throat (19) sized to accommodate a second pipe string while a first pipe string is held within the jaws (12, 13) of the tong is disclosed. The inventive backup tong facilitates operations on dual pipe strings by allowing the tong to grip not only the closer of two pipe strings, but also the farther of the pipe strings by allowing the nearer pipe string to reside in an inner throat of the backup tong, between the gripping members (16, 17) of the tong and the body of the backup tong, while the farther pipe string is held between the gripping members. The inventive backup tong thereby allows the operator to grip either of the pipe strings from a single side, eliminating the side-to-side movement (and corresponding time and risk of harm) which is required when using prior art backup tongs.</p> |
