GB722040A - Improvements in and relating to tools for sealing the ends of tubular elements subjected to internal pressure - Google Patents

Abstract

722,040. Devices for stopping pipes. AKTIEBOLAGET SVENSKA MASKINVERKEN April 7, 1952. [April 16, 1951] No. 8858/52. Class 99 (2). A tool for removably securing a sealing block 25 over the open end of a tube 12 subjected to internal pressure comprises a body 1 having rigid, spacedapart side walls 30, 31 provided with opposed wedge surfaces 3, 4 which may be plain or constitute parts of a cone, converging towards each other and spaced axially from a transverse member 15 connecting the walls 30, 31, and jaw members 10, 11 which slidably engage the surfaces 3, 4 and have inner gripping surfaces 33, e.g. formed by teeth. There are means, such as a spindle 13 screwed into the member 15, which are operable to press the block 25 into sealing engagement with the end of the tube and which by reaction on the member 15 urge the body 1 in a direction to force the jaws 10, 11 into gripping engagement with the wall of the tube. The jaws 10, 11 may be curved in cross-section and secured to resilient arms 6, 7 connected by a cross-piece 5, and a compression spring 21 may be disposed about the spindle 13 and between the member 15 and the cross-piece 5. A head 22 of the spindle 13 may bear on the block 25 which may be provided with a passage 34 for a pressure medium and seat on the end of the tube with the interposition of a sealing washer 26. In operation, the jaws 10, 11 are opened by turning the spindle 13 to draw up the head 22 into contact with the cross-piece 5 and compress the spring 21, the tool then being positioned over the end of the tube 12. By turning the spindle 13 in the opposite direction and with the block 25 in place the spring expands to depress the cross-piece 5 and the arms 6, 7 so that the wedge-action of the surfaces 3, 4 presses the jaws 10, 11 against the tube, and the spindle exerts pressure on the block. In a modification, the spring 21 is replaced by a sleeve screwed into the cross-piece 5 and into which the spindle is screwed, the sleeve being turned independently of the spindle 13 to operate the jaws 10, 11.