| 摘要 |
PURPOSE:To easily carry out repairing of a tube to be repaired by fitting hollow or semi- hollow rings made of a shape memory alloy into both ends of a tube used for repairing, and after the insertion, heating the rings to restore the same to the original sectional shape, and hermetically sealing gaps between both tubes. CONSTITUTION:Hollow rings 3 and 3 the outer diameter d0 of each of which is larger than the inner diameter di of a tube to be repaired 1 but smaller than the outer diameter D0 of a pipe 2 used for repairing, and made of a shape memory alloy, are prepared. The thus prepared hollow rings 3 and 3 are subjected to coil working so that the outer diameter and the inner diameter of each rings 3 become d0' and d1' respectively that is, becomes flat. Then, the rings 3 and 3 which have been subjected to cold working are fitted into both ends of the pipe 2 used for repairing. The pipe 2 used for repairing is inserted into the pipe 1 to be repaired so that the damaged parts (e) and (e) of the pipe 1 to be repaired come between the rings 3 and 3. A heater is inserted into the pipe 2 used for repairing to heat the rings 3 and 3. The rings 3 and 3 are restored to its sectional shape by the shape memory effect and hermetically seal the gap between the pipes 1 and 2. The restored rings 3 and 3 receive pressures by internal and external pipes 1 and 2, and the rings 3 and 3, the inner wall of the pipe 1 to be repaired and the outer wall of the pipe 2 used for repairing are put into a hermetically attached state thereby to prevent the internal fluid from leaking. |
