Fremgangsmåde og apparat til formning af rørformede forbindelser

摘要

The apparatus of the present invention is directed to a replacement cage assembly (106) to modify a conventional power tong (100) to enable the power tong to grip and rotate smaller diameter tubular segments (90). The method of the invention is directed to modifying a power tong (100) to grip and rotate a tubular segment of a diameter smaller than could be gripped by the unmodified power tong (100). The invention provides a rotary gear insert (240), having an interior second cam surface, rotatably captured intermediate an upper cage plate (230) and a lower cage plate (210) and slidably receivable within the conventional rotary gear of the power tong (100) and to cam and rotate a plurality of replacement gripping jaws (220, 221) pivotally captured adjacent the second cam surface (240) and intermediate the upper cage plate (230) and the lower cage plate (210).