Patent ID: 8646304

Claim:
A method of forming a grain bin floor panel comprising: a) providing a unitary piece of sheet metal; b) providing a roll former comprising a plurality of rollers and at least one joining tool arranged to progressively form the unitary piece of sheet metal into a floor panel structure; c) using the rollers of the roll former, forming a central support leg of the floor panel structure to extend in a longitudinal direction between opposing ends of the floor panel structure by: i) folding the unitary piece of sheet metal to define first and second upright portions having upper ends and lower ends and a lower portion connected between the lower ends of the first and second upright portions which are spaced apart from one another; and ii) bending the lower portion to be concave such that a central portion of the lower portion is raised upwardly in relation to the lower ends of the first and second upright portions; d) using said at least one joining tool, joining the first and second upright portions to one another in proximity to the upper ends; e) using the rollers of the roll former, folding the sheet metal to define a first floor surface, a second floor surface, a first side support leg and a second side support leg of the floor panel structure wherein: i) the first side support leg and the second side support leg extend in the longitudinal direction and are spaced laterally outward from opposing sides of the central support leg; ii) the first floor surface is connected between the first side support leg and the upper end of the first upright portion of the central support leg; and iii) the second floor surface is connected between the second side support leg and the upper end of the second upright portion of the central support leg; and f) providing ventilating perforations in the first floor surface and the second floor surface; wherein the lower portion of the central support leg is bent to be concave prior to defining at least one of the first floor surface, the second floor surface, the first side support leg and the second side support leg of the floor panel structure.