Patent ID: 7695026

Claim:
A tube device including a casing, and a device element which is placed in said casing, wherein said casing comprises: a tube made of a synthetic resin; a pair of lid members which are made of a synthetic resin; a pair of union nuts which are made of a synthetic resin, which are fitted onto one and other end portions of said tube, and which are screwed to end portions of said lid members having receiving ports, respectively; and a sealing portion which is formed in at least one place for each of said end portions of said tube by closely contacting said end portion of said tube with a sealing face of a corresponding one of said lid members, said end portion of said tube and said sealing face of said lid member being closely contacted with each other by causing a corresponding one of said union nuts to press said tube from an outside of said tube, said corresponding one of said union nuts fastening said end portion of said lid member by screw advancement toward said end portion of said lid member, thereby pressing said tube from the outside of said tube, wherein said device element is a heat exchange tube which is made of a synthetic resin, and in which an outer periphery is surrounded by said tube made of synthetic resin and connecting portions which are disposed on said pair of lid members made of a synthetic resin, and to which outlet ports of said heat exchange tube, and pipes for introducing and discharging a fluid that is passed between an inner side of said casing and an outer side of said heat exchange tube are connected, respectively, wherein an inner ring is formed in each of said end portions of said tube, said inner ring having: a press-insertion portion which is pressingly inserted into said end portion of said tube to increase a diameter of said end portion, thereby expanding said end portion so as to have a protruding shape; and a projection portion which projects from said end portion of said tube, and wherein said sealing portion is formed by close contact between: a sealing face configured as a tapered face which is formed inward of an entrance of a receiving portion of said lid member, and in which a diameter is gradually increased toward an outer side in an axial direction of said lid member; and a projection end face formed by a tapered face which is formed in a tip end of said projection portion of said inner ring.