CLAMPING DEVICE FOR STEEL PIPE

PURPOSE:To clamp various steel pipes, differing in external diameter, easily and securely by rotating a clamping roll which has a groove at its external circumference until the groove matches with the external diameter of a steel pipe, and then clamping the steel pipe by laterally moving the clamping roll. CONSTITUTION:Clamping rolls 54 and 54a having grooves 55 and 55a on the arcs differing in radius successively to the external circumference are stood rotatably on both sides on a quenching floor 1. A rod 59 is displaced by a hydraulic cylinder to move the clamping rolls 54 and 54a laterally, increasing the interval between the two. Then, handles 57 and 57a are rotated to rotate the rolls 54 and 54a until the radii of the arc-shaped grooves 55 and 55a match with that of the steel pipe. Then, the steel pipe is sent on the floor 1 along a receiving roll 4 to bring its end part into contact with the nozzle of a water supply pipe, and the steel pipe is held by a holding device; and the rod 59 is moved in the opposite direction to move the rolls 54 and 54a in a pass-line direction, and the steel pipe is clamped in the arc-shaped grooves 55 and 55a.