| 摘要 |
PROBLEM TO BE SOLVED: To provide a highly reliable live pipe branching joint capable of securely forming an eccentric bored hole in an original pipe. SOLUTION: A boring piston 11 lowering in parallel with a vertical neutral face at a position eccentric from the vertical neutral face of the original pipe 1 is incorporated into a boring operation port 9 of a first split joint 4. In the boring piston 11, a cutting edge part 13 is formed at the axial tip and a through hole 14 is formed in the axial intermediate part. A hydraulic cylinder 17 is detachably fixed to an opening end part 9a above the boring piston 11 inside the boring operation port 9. A tip part 20a of a cylinder rod 20 advancing/retracting inside the hydraulic cylinder 17 is made abut on the axial rear end face of the boring piston 11. By lowering the boring piston 11 along with advancement of the cylinder rod 20, part of a peripheral wall of the original pipe 1 is shaved off by the cutting edge part 13 to form the eccentric bored hole 31. COPYRIGHT: (C)2008,JPO&INPIT
|
