PURPOSE: To connect composite pipes so as to obtain sufficiently excellent cut-off properties only by adding simple work to the flange joint method of inner surface resin coated metal pipes.
CONSTITUTION: A flange part (f) is formed to the end part of a composite pipe wherein a synthetic resin layer is applied to the inner surface of a seam- welded meta pipe by forming the flange parts (f), (f) of both pipe end parts of the composite pipes are superposed one upon another directly or through a synthetic resin sheet (p) and the synthetic resin layers 221, 221 of those flange parts (f), (f) or a sythetic resin layer 222 and the synthetic resin layer (p) are mutually welded and both flange parts (f), (f) are grasped by grasping members 3, 3. A current supply type heating element is built in the synthetic resin sheet (p) and a current is supplied to the current supply type heating element to weld the synthetic resin layer and synthetic resin sheet (p) of the flange part (f).
GOTO YASUSHI
MATSUMOTO KOJI
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