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

A fluid supply interruption free method comprising:

• an enclosing step for hermetically enclosing a part of an existing pipe by a seal-up housing, said seal-up housing comprising a plurality of housing parts segmented in the circumferential direction of said existing pipe;
• an opening formation step for forming a circular or grooved opening in said existing pipe within said seal-up housing, said opening extending through about 180 degrees or through the angular range slightly smaller than 180 degrees;
• a water stop step for stopping the flow of water through the interior of said existing pipe by allowing a gate for stopping the flow of water through the interior of said existing pipe to enter the interior of said existing pipe through said opening;
• a removal step for removing said gate from said opening;
• and
• a hermetically closing step for fitting an anticorrosive member into said opening, said anticorrosive member including a pressure contact portion made of elastomer coming into pressure contact with a cut surface of said opening over substantially the entire periphery, and a rigid portion integrally formed with said pressure contact portion and having a rigidity enough to resist the water pressure acting on said opening.

A fluid supply interruption free cutting apparatus comprising:

• a seal-up housing comprising a plurality of housing parts segmented in the circumferential direction of an existing pipe, said seal-up housing hermetically enclosing a part of said existing pipe;
• and
• a drill having a milling cutting tool, said seal-up housing having a structure suited to turn around said existing pipe in the circumferential direction thereof,
• a first housing part which is one of the housing parts having integrally formed a cutting tool insertion aperture through which said milling cutting tool is inserted and a gate passage aperture through which a gate passes for stopping the flow of a fluid through the interior of said existing pipe after cutting of said existing pipe,
• said fluid supply interruption free cutting apparatus being provided with a first operation valve arranged to open or close said gate passage aperture and with a second operation valve arranged to open or close said cutting tool insertion aperture.

A fluid supply interruption free valve inserting apparatus comprising:

• a seal-up housing comprising a plurality of housing parts segmented in the circumferential direction of an existing pipe, said seal-up housing hermetically enclosing a part of said existing pipe;
• and
• a gate arranged to be inserted for cutting off the flow of a fluid through the interior of said existing pipe after cutting of said existing pipe,
• a first housing part of said seal-up housing having integrally formed a cutting tool insertion aperture through which a milling cutting tool is inserted and a gate passage aperture through which said gate passes,
• said fluid supply interruption free valve inserting apparatus being provided with a first operation valve arranged to open or close said gate passage aperture and with a storage casing which stores said gate while said gate is opened,
• said storage casing and said seal-up housing being each provided with a flange adapted to join said storage casing storing said gate to said seal-up housing with said first operation valve closed.