HEAT EXCHANGER FOR HEAT STORAGE TANK

摘要

PROBLEM TO BE SOLVED: To obtain a lightweight heat exchanger for heat storage tank excellent in thermal durability and rigidity operable over a wide temperature range by lining the inside of an aluminum pipe with a thermoplastic synthetic resin pipe and coating the outside of the aluminum pipe with a thermoplastic synthetic resin pipe. SOLUTION: A composite pipe is produced by lining the inside of an aluminum pipe 1 entirely with a non-crosslinked polyethylene or crosslinked polyethylene pipe 2 and coating the outside of the aluminum pipe 1 entirely with a non-crosslinked polyethylene or crosslinked polyethylene pipe 3. The aluminum pipe 1 is produced by overlapping one side edge of a stripe plate and subjecting the overlapped part to ultrasonic welding. Both polyethylene pipes 2, 3 are cylindrical. The polyethylene pipes 2, 3 are bonded rigidly to the aluminum pipe 1 and integrated to constitute a composite pipe.