Patent ID: 7866196
Filing Date: 2011-01-11
Classification: B21C,B21D,B23K

Abstract:
1. A method for manufacturing a circular metal tank wall from an elongate metal sheet, wherein said metal sheet has an upper edge, said method comprising the steps of: (a) providing the elongated metal sheet; (b) bending the upper edge of the metal sheet to produce an upper bend along the upper edge; (c) bending a lower edge of the metal sheet produce a lower bend along the lower edge; (d) aligning the lower bend into proximity with the upper bend; (e) welding the upper edge of the metal sheet to the lower edge of the metal sheet to form the circular tank wall, wherein the upper bend and the lower bend of the metal sheet cooperate to form a roller track, and wherein the roller track has two opposing roller track sides spaced apart to accommodate rollers that can engage the roller track and support the tank wall as it is being constructed; and, (f) rotating the tank wall about its longitudinal axis on the rollers such that the tank wall moves upwards as Step (d) and Step (e) are performed.