INJECTION MOLDING SYSTEM AND PIPING MEMBER

PROBLEM TO BE SOLVED: To provide an injection molding system, a sleeve, and a piping member preventing occurrence of a crack in a joint part between a flange part and a tubular part of piping even by repeated heating and cooling, for improving reliability. SOLUTION: When the sleeve 140A is inserted and positioned in a coupling part of piping members 110 and 120, the sleeve 140A is positioned on the inside close to the joint between the flange parts 112 and 122 and the tubular bodies 111 and 121, and then, a heat insulation effect is exhibited by the sleeve 140A. The sleeve 140A is formed of a material having a linear expansion coefficient different from that of the piping members 110 and 120, and a lower thermal conductivity. Preferably, an outside diameter of a cylindrical part 141 of the sleeve 140A is set to be smaller than inside diameters of the tubular bodies 111 and 121 and the flange parts 112 and 122, and a clearance 200 is formed between the outer circumference face of the cylindrical part 141 and the inner circumference faces of the tubular bodies 111 and 121 and the flange parts 112 and 122. COPYRIGHT: (C)2011,JPO&INPIT