PURPOSE: To provide the pipeline comprising an elastomer material and excellent in lightweight properties, heat resistance and durable period and capable of transporting a corrosive fluid having possibility becoming high in temp. while ensuring the good tightness related to a transported fluid.

CONSTITUTION: A pipeline 10 is equipped with flexible or rigid sections or linear parts 13, 14 provided between two terminal ports 11, 12 so as to be adjacent thereto, the curved part (also flexible or rigid) held between the parts 13, 14 and a bellows 20 applying the possibility of relatively large deformation to the pipeline. The average axis of the pipeline 10 is curved in a three- dimensional space (3D) and the pipeline is formed based on a plastic material, especially started from a simple or elastomer alloy-type thermoplastic elastomer(TPE) material.