SQUARE CAN MANUFACTURING METHOD AND SQUARE CAN MANUFACTURING DEVICE

To provide a square can manufacturing method and a square can manufacturing device that suppress occurence of ununiformity in thickness of a long side wall without increasing cost of manufacture.SOLUTION: A square can manufacturing method includes a drawing and ironing process in which drawing and ironing are performed for a planned cylindrical part of an intermediate molded product. A die and a punch are formed so that in the state that the punch is inserted in a die processing open hole 41a in an unloaded condition, a short side direction interval W1 between a long side direction center part of a punch long side wall processing part 42b and a die long side wall processing part 41c becomes narrower than a short side direction interval W2 between long side direction both end parts of the punch long side wall processing part 42b and the die long side wall processing part 41c.SELECTED DRAWING: Figure 6 【課題】製造コストを増大させることなく、長辺壁の肉厚に不均一が生じることを抑制する角型缶製造方法および角型缶製造装置を提供すること。【解決手段】中間成形品の筒状部予定部に絞りしごき加工を施す絞りしごき工程を含み、ダイおよびパンチは、ダイ加工貫通孔４１ａ内にパンチを無負荷状態で挿入した状態で、パンチ長辺壁加工部４２ｂの長辺方向中央部とダイ長辺壁加工部４１ｃとの間の短辺方向間隔Ｗ１が、パンチ長辺壁加工部４２ｂの長辺方向両端部とダイ長辺壁加工部４１ｃとの間の短辺方向間隔Ｗ２よりも狭くなるように形成されている角型缶製造方法。【選択図】図６