Cutting, valve insertion and corrosion-resistant works without fluid supply interruption

Abstract

A fluid supply interruption free cutting apparatus of the present invention comprises a seal-up housing and a drill. The drill has a milling cutting tool turned by a motor. The seal-up housing is of a structure suited to turn in the circumferential direction of an existing pipe. A first housing part of the seal-up housing is formed with a cutting tool insertion aperture through which the cutting tool is inserted and with a gate passage aperture through which a gate passes that is inserted for cutting off the flow of a fluid through the interior of the existing pipe after cutting of the existing pipe. The first housing part is provided with a first operation valve to open or close the gate passage aperture and with a second operation valve to open or close the cutting tool insertion aperture. An anticorrosive member is fitted in the opening formed in the cutting of the existing pipe. The anticorrosive member include a pressure contact portion made of elastomer coming into pressure contact with a cut surface of the opening over substantially the entire periphery and a rigid portion integrally formed with the pressure contact portion.—has been inserted therein.