GB734133A - A machine for stripping metal tubes from mandrels - Google Patents

Abstract

734,133. Separating mandrels from work. WELDLESS STEEL TUBE CO., Ltd. Dec. 15, 1953 [Dec. 23, 1952], No. 32548/52. Class 83 (4), In a machine for stripping tubes i, Fig. 2, from mandrels j after rolling or drawing operations a pair of rolls d for gripping and pulling the mandrel or tube have means responsive to the pulling force for increasing the grip of the rolls. In an example in which the rolls d engage the mandrel j and pull it out of the tube i against a stripper h, the rolls are mounted in a pivoted frame c and a lever k pivoted on the frame and connected to a stationary thrust rod t is adapted to exert pressure on the upper roll d in response to movement of the frame. The lever k comprises parallel arms interconnected by cross-members n, o and is carried on a shaft p. It normally presses on the bearings of the upper roll d through the cross-member n and blocks q under the action of a spring-loaded plunger s slidingly mounted on the frame and connected to the cross-member o. In operation, when an abnormal extracting force occurs, the frame c is drawn towards the stripper h, thereby causing the pushrod t to tilt the lever k and effect an increased pressure of the rolls d on the work. In a modification the frame c may be slidable on the machine bed a and the rolls may grip the tube i, the mandrel j being held by a gripper. Hydraulic pressure means for the rolls responsive to the separating force between the tube and mandrel may alternatively be used.