| 摘要 |
PROBLEM TO BE SOLVED: To enable cutting edges to positively and stably abut against the inner periphery of a pipe to cut it at positions when the pipe is cut from inside by rotating cutters without using fire tools. SOLUTION: Plural grippers 3, 4 for performing pressing and fixing to the inner peripheral surface of an objective pipe to be cut are provided at the end of a shaft 2 inserted into the objective pipe 1 to be cut, radially and at a distance apart vertically (laterally). Plural cutters 5 which are rotatably driven around the shaft 2 and the cutting edges 13a to 13d of which are advanced and retracted by a cylinder or a jack, are provided at the shaft 2 radially at the positions between the grippers 3, 4 provided up and down (right and left) stages, and a rotation-driving power unit of the cutters 5 is also provided at the end of the shaft 2.
|
