Power tong unit

摘要

A power tong unit having a gear train in which one or more of the gears in the gear train have removable and replacement roller tooth elements, in lieu of conventional gear teeth. In one embodiment, the ring gear and pinion gears have roller tooth elements, and idler gears disposed between the ring gear and pinion gears, have a semi-circular tooth root profile to mesh with the roller element gear teeth. The ring gear of the power tong unit may also have a removable section. A means for removing the removable section from the ring gear, and moving it to a position in which a tubular can be inserted into a central opening in the ring gear, may include a hydraulic cylinder, a clamping mechanism, and a cam surface to generate rotation of the removable section once lifted out of engagement with the ring gear.

主权项

1. A power tong unit for the makeup and breakout of threaded tubulars, comprising a gear train, wherein said gear train comprises:
a pinion gear rotated by a power means; a ring gear driven directly or indirectly by said pinion gear, wherein said ring gear comprises roller tooth elements, and wherein: said ring gear comprises a circumferential groove about an outer edge, forming a circumferential groove thereabout and upper and lower lips bounding said groove; a plurality of holes through at least one of said upper and lower lips; said roller tooth elements are inserted through said holes in one of said upper or lower lips, and a cap retains said roller gear tooth elements in place.