DEVICE FOR CUTTING-IN OF WATER-SUPPLY LINE Russian patent published in 1997 - IPC

FIELD: construction and plumbing engineering. SUBSTANCE: device ensures cutting-in of new water-supply line with diameter of 50 mm and larger into corresponding existing water-supply line without use of hand-carried electric or pneumatic drilling machines with full guarantee against any water leakage during operation. Device permits cutting-in of new line into existing without disconnecting existing line from network and draining water from it. Device has two pipe unions. Lower pipe union 2 is welded to existing line and is provided with shut-off valve, cutting tool in the form of drill bit 13 connected with drilling drive by rotating spindle 12 which passes through sealing gland 11. Fastened to pipe union welded to existing water-supply line is wedge-type gate valve 4 and diameter of its bore is equal to inner diameter of new water-supply line being cut-in. Secured to gate valve 4 through adapter 5 is worm-gear reducer 6 with electric drive unit for rotation of cutting tool and with screw 8 for feeding this tool in process of cutting. Use is made of combination cutting tool made up of spiral drill bit and annular drill bit, and cutting part of spiral drill bit protrudes above surface of annular drill bit teeth by 10-20 mm ensuring reliable direction of work without vibration, with cooling annular drill bit with water in process of cutting. EFFECT: high efficiency. 1 cl, 2 dwg