PURPOSE: To obtain a double pipe type compressor which cuts down manufacturing manhour, reduces material cost and enhances dramatically the efficiency of heat exchange by increasing a heat transfer area of fins.

CONSTITUTION: This double pipe exchanger comprises an inner tube 10 which is provided with fins 13 on its outer peripheral surface and an outer tube 11 which houses the inner tube 10 inside in its longitudinal direction where heat exchange water is adapted to flow inside the inner tube in continuity while a heat-exchanged fluid is arranged to flow between the inner tube 10 and the outer tube 11. The inner tube 10 and the outer tube 11 are formed in one piece. The fins 13 are installed with a specified span in their peripheral direction integrated with the inner tube 10 and projected longitudinally and radially in their cross section. The inner tube 10, the outer tube 11 and the fins 13 are twisted longitudinally at a specified angle.