BRANCH OPENING FORMING DEVICE AND BRANCH OPENING FORMING METHOD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a branch opening forming device provided with the structure capable of forming a branch opening having the predetermined area in a short time while reducing the working man-hours. SOLUTION: This branch forming device is provided with half branch forming adapters 1 capable of covering the whole circumference of an existing pipe line 2 and forming a closed space S between the peripheral surface of the existing pipe line in the covering condition, and one of the half branch forming part 1A is provided with a branch port 1A2 facing to the peripheral surface of the existing pipe line 2 and a shutter device 3 arranged closer to the peripheral surface side of the existing pipe 2 than an opening of the branch port 1A2 so as to control the communicating condition between the closed space S and the opening. The branch forming adapters 1 can be rotated in the circumferential direction in the condition that the adapters 1 cover the whole circumferential area of the existing pipe 2, and in the condition that the branch port 1A2 is faced to the branch forming position, a boring machine 4 capable of boring a hole having a diameter smaller than that of the existing pipe 2 is installed in the branch port 1A2 so as to bore plural holes Pa in the circumferential direction.