To suppress the camber of a work and also to accurately form a joined part with respect to a groove forming apparatus of a heat exchanger tube.
The groove forming apparatus of the heat exchanger tube is constituted so that a first grooved roll 110 provided with a plurality of roll projecting parts 111 and roll groove parts 112, and a second grooved roll 120 provided with a plurality of roll projecting parts 121 and roll groove parts 122 are arranged at prescribed intervals, wherein the roll projecting parts 121 of the second grooved roll 120 are arranged so as to be positioned between the adjacent roll projecting parts 111 of the first grooved roll 110. A work 200 supplied between the two rolls is pressed to the sides of the roll groove parts 122, 112 of the other roll each other by respective roll projecting parts 111, 121 of the first grooved roll 110 and the second grooved roll 120.
Iwa Saki Kokuni
Kawamata Sumio
Masakazu Ito
Shunichi Takahashi
Toshio Takamatsu
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