| 摘要 |
An elevator for drill pipe which includes at least two jaws for supporting a length of pipe and structure for maintaining the jaws in clamping engagement with the pipe. The structure includes linkage means coupled to the jaws for maintaining the jaws clamped to the pipe when the elevator and pipe are urged apart by gravity due to the weight of the pipe as when the pipe is raised or otherwise supported by the elevator. Additionally or alternatively, the elevator includes a pressure actuator assembly connected to the jaws for applying a positive force against the jaws for maintaining the jaws clamped to the pipe independent of the effect of gravity and, thus, independent of the orientation of the elevator.
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