POWER TONGS WITH IMPROVED HYDRAULIC DRIVE

摘要

POWER TONGS WITH IMPROVED HYDRAULIC DRIVE Power tongs are described for making up and breaking apart joints of pipe. The hydraulic system of the tong comprises a tandem fluid motor which enables both forward and reverse operation of the tong in one of several selected speed/torque ranges by operating a pair of control handle. The open throat tong includes a door latching mechanism for automatically locking and unlocking the tong door when activating the tong hydraulic system. The tong dies come into gripping engagement with the pipe over a large composite arcuate angle to increase the pipe gripping ability of the tong.