Patent GB-965132-A (GB)
Title: Method and apparatus for sealing in-situ cracks and breaks in a pipeline
IPC: F16L55/1645
Filed: 1962-04-24
Abstract: 965,132. Repairing pipes. CEMENT LININGS PTY Ltd. April 24, 1962 [April 20, 1961; Jan. 12, 1962], No. 15458/62. Heading F2P. A method of sealing in situ, cracks and breaks in a pipe line comprises the steps of inserting an inflatable tube 5 into a pipe section to be repaired, inflating the tube to substantially fill the pipe section leaving a space between the tube and the pipe, injecting sealing material into the space so that the whole length of the pipe section is grouted in one operation and thereafter deflating and withdrawing the tube. As shown in Fig. 1, an inflatable, rubber tube 5, together with a helical wire 6, is disposed in the pipe line 1, the ends of the tube being closed by a clamp 8 and a bulkhead 9 and connected by a hose 11 to a 3-way valve 12, pressure gauge 13, pressure reducing valve 14 and an air compressor 15. The tube is inflated and sealed against the pipe line by sealing rings 16, 17 and a grout consisting of two aqueous solutions held in the supply and pumping device 20 is fed through hoses 21, 22 to the mixing chamber 23, in which a stiff rubbery gel is formed, and then via the hose 24 to the duet 7 defined by the wire 6. The grout is forced under pressure through the pipe line to fill the defects therein and until the grout flows from the tap 26. After the grout has set, the tube 5 and wire 6 are withdrawn from the pipeline. The pipeline may be treated in sections. In a modification, the tube 5 is inserted in the pipeline, one section of the latter being sealed by rings 30, 31, Fig. 2, the tube then being inflated from an air compressor 15 and sealing material being pumped from the supply and pumping unit 20 via a mixing chamber 23 into the space between the tube and pipeline. The tube is then further inflated until sealing material flows from the valve 26 which is then closed and the tube fully inflated to force the sealing material into the pipeline defects 29. This cycle of operations can if necessary be repeated a number of times. Effectiveness of the treatment is checked by slightly deflating the tube and supplying water via a hose 35 to the space between the tube and pipeline satisfactory sealing treatment being indicated by a stationary water level at the valve 26. In another modification, the method of the invention is adapted for treating vertical pipelines, a riser being sealed from a main pipe and branch pipe by inflatable bags and the tube, prior to inflation, be folded and lowered into the riser so that the fold in the tube rests on the sealing bag at the junction of the main pipe and riser. In a further modification, the tube 5 is shorter than the distance between the branches of a pipe line, is pulled through the pipe line from section to section and comprises three compartments 45, 46, 47, the compartments 46, 47 being inflated to form a tight seal with the pipe line. Hoses 49, 50, 51 supply compressed air to the compartments, and ducts 55, 56 for the sealing material are connected to a mixing chamber 57. A temperature-sensing device 62 sends a signal to a device 64 to indicate that setting of the sealing material has occurred. The sequence of sealing operations may be controlled automatically in a predetermined manner either by electrical, hydraulic or pneumatic means.