PURPOSE:To relax a stretch of a wound and joined part, and a compressive stress, and to prevent the generation of a lap crack, by providing a blanking hole on one superposed part which is joined through a thermoplastic resin bond of a can drum, and bent in case of winding and joining a can cover. CONSTITUTION:Polyamide series thermoplastic resins 3, 4 are attached to both side end parts 2a, 2b of a base material 1 for a can, and both ends 8, 9 are superposed, and joined by high frequency heating. In that case, a blanking hole 7 is provided on at least one of superposed parts W which have been separated by a prescribed distance from the upper and lower end edges of a cylindrical body. When said blanking hole 7 is positioned in a bent party 17 of a double winding part 13 which has wound and joined a can cover 12, a stretch and a compressive stress generated in the bent part 17 are relaxed by this blanking hole 7, and the generation of a lap crack can be prevented.
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