GB1270059A - Pipe bending method and device - Google Patents

Abstract

1,270,059. Angular bending. A. I. GALPERIN, L. V. VISHNYAKOV and B. V. POKROVSKY. 4 Aug., 1970, No. 37509/70. Heading B3E. A method of cold bending pipes comprises introducing a device with bending elements, into the pipe, bending the pipe by actuating said elements and moving said device freely inside the pipe after bending for the next bending operation. The device comprises a rigid frame 1 mounted on spring-loaded wheels 2 and is driven through the pipe by an electric motor 21 through a speed reducer 22 coupled to one of the wheels. Secured to the middle of the frame is a bending shoe 7 facing the stretching portion of the pipe 6. On the ends of the frame are located the bending elements comprising two hydraulic cylinders 8 mounted for swinging on rolls 9 and held in the vertical position by springs 10. The cylinders carry articulated segment heads 12. Expansion mechanism installed in the middle of the frame for improving the stability of the pipe wall under compression during bending comprises three vertical 13 and six horizontal 14 hydraulic cylinders carrying articulated curved segment heads 16. The vertical cylinders 13 are connected by rods 18 to the bending shoe 7 and all cylinders are powered by an electric motor 20 (Fig. 6, not shown). Guide rollers 23 locate the frame in the tube. In operation the pipe 6 is placed on supports 24 one of which has a seat 25 for accommodating the device at the beginning and end of the operation. The device is rolled into the pipe and stops adjacent the seat 25 whereupon the segment heads 16 are expanded into contact with that part of the pipe to be deformed. The segment heads 12 of the bending element are actuated to bend the pipe (Fig. 8). The end of the pipe rising during bending is supported by a hoist 27.