CONNECTION STRUCTURE OF METALLIC PIPING SYSTEM, METALLIC PIPE, AND MANUFACTURE OF METALLIC PIPE

摘要

PROBLEM TO BE SOLVED: To simply and inexpensively connect together a compressor body formed of an iron metallic material and a heat transfer pipe formed of a copper metallic material without flux and besides to provide connection structure with low cost being high in reliability on a connection part. SOLUTION: This connection structure comprises a compressor body made of iron base metal material; a heat transfer pipe made of a copper base metallic material; and a coupling pipe having an outer peripheral part welded to the compressor body and meanwhile an inner peripheral part welded to the heat transfer pipe. The coupling pipe has an outer peripheral part formed of an iron metallic layer 3A, and an inner peripheral part formed of a copper metallic layer 3B. A weld part is formed at a part in its peripheral direction since it is formed through electro-resistance-welding processing the coupling pipe. The maximum thickness Ta of the iron metallic layer 3A of the weld is 60-90% of a coupling pipe thickness T and meanwhile, the thickness Tb of the iron metallic layer at other part than the weld is 50-80% of the coupling pipe thickness T.