PLATE TYPE ICE MAKING HEAT EXCHANGER

摘要

PROBLEM TO BE SOLVED: To enable a plate type ice making heat exchanger to be sufficiently satisfying strength required in an ice storage type air conditioner. SOLUTION: A flow passage 8 for a cooling medium is formed by a method wherein welding parts 4 are provided to requisite locations under a state in which two plate members 2 are overlapped to each other, thereafter unwelded parts of the plate members are bulged out and deformed by application of expansion pressure applied from inside. With such an arrangement as above, compression residual stress is induced in the welding parts 4 to enable a fatigue strength to be substantially increased and further it may sufficiently satisfy a strength required by the ice storage type air conditioner.