Pipe arrangement structure, constant flow valve interposition construction method, divider needle and valve gear null for constant flow interposition

摘要

PROBLEM TO BE SOLVED: To provide a piping structure capable of decreasing the size of a closed case and hardly occurring breakage of an existing pipe, and to provide an existing pipe cutting method and a water supply non-cutting-off valve insertion method. ;SOLUTION: This piping structure comprises an existing pipe 1 having a groove-form cut groove 12C notched throughout a range of approximate 180° in a peripheral direction of the existing pipe 1, a closed case divided into a plurality of sections in the peripheral direction of the existing pipe 1 and surrounding in an airtight state the existing pipe 1, and a rubber packing 8d making contact with the inner peripheral surface 1b of the existing pipe 1 and a cut surface 12f forming the cut groove 12C in the existing pipe 1 in a closed state. A rubber packing 8d is forced into pressure contact with the inner peripheral surface 1b and a cut surface 12f by movement through the closed case in the radial direction of the existing pipe 1 and penetration of fluid from the cut groove 12C through the existing pipe 1. A sluice valve element 8a is provided to stop the flow of fluid in the existing pipe 1 and a valve stem is provided to radially move the valve element 8a.;COPYRIGHT: (C)2000,JPO