Abstract: An improved rotary drive apparatus for a drill spinner, casing tong, or the like. The apparatus has a drive wheel and idler wheels adapted to drive an endless loop member trained around a cylindrical member to be driven. Pipe engaging rollers are utilized which have freely rotating flanges. The incporation of these freely rotating flanges increases torque output, reduces vibration, reduces wear on the flanges, and reduces likelihood of damage to the cylindrical member to be driven. Reaction rollers are utilized which eliminate or reduce vibration of the cylindrical member during operation of the apparatus and which increase torque output.

Abstract: An apparatus for imparting torsion to a tubular member, including a body member, an arm member, a saddle member, and a loop means such as a chain. Torsion is imparted to the tubular member by inducing tension into the chain entrained around the tubular member so that the tubular member is brought to bear against the body member or dies in the body member. A variety of configurations of the apparatus are possible, permitting adjustment to accept different diameter tubular members and assuring maximum positive load reaction.