Patent ID: 6357471
Filing Date: 2002-03-19
Classification: F16L,Y10S,Y10T

Abstract:
A cutting tool suitable for cutting an already-installed water pipe in non-water-flowing-stopping condition, comprising:a substantially cylindrical cutter body having a base end surface, a free end surface and an outer circumferential surface, a plurality of first tips projecting forward from said free end surface of said cutter body, a plurality of second tips projecting outward from said outer circumferential surface of said cutter body, and a plurality of recesses formed in said cutter body, wherein (1) said recesses extend to a substantially central portion of said free end surface, and have a shape of a fan when said recesses are viewed from said free end surface, (2) said cutter body has a plurality of divisional surfaces defining each of said recesses, (3) each of said divisional surfaces extend in the radial direction of said cutter body, (4) not less than one first tip and not less than one second tip are fixed to one of said divisional surfaces, and (5) during a grooving operation in which (a) said cutter body is rotated about a longitudinal axis thereof and (b) said cutter body is fed in a circumferential direction of said already-installed water pipe so that said second tips form a cut groove in said already-installed water pipe, said recesses form discharge flow passages for discharging water and cutting chips produced due to said grooving operation to an exterior of said already-installed water pipe.