| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a renewal method of a conduit which can avoid an erroneous operation after construction and complicated maintenance management, and can also suppress a cost, and the conduit.SOLUTION: A new conduit 11 is laid along a zone S1 to be renewed in an existing conduit 1 while holding a fluid flowing state, an upstream side and a downstream side of the new conduit 11 are made to communicate with the existing conduit 1 via communication conduits 15 and 16, and a bypass is formed by arranging changeover valves 31, 32 and 36 at branched parts 21 and 22 in which the communication conduits 15 and 16 are merged with the existing conduit 1, and a branched part 26 in which the communication conduit 16 is merged with the new conduit 11, respectively. After switching a flow passage to the bypass from the existing conduit 1 of the zone S1 to be renewed, the existing conduit 1 of the zone S1 is removed. A connecting port 21c which is connected to the removed existing conduit 1 is covered with a lid, or closely sealed, and after that, a valve body 31A of the changeover valve 31 is removed.</p> |
