Production of load bearing panels.

摘要

A load bearing panel is made from a top sheet (38 min ) and a stiffening web (39) which is made by giving a flat sheet a plurality of projections (15) to make it more rigid for which purpose the flat sheet is deformed by cold die forming using circular or nearly circular dies and circular, domed punches so as to form domed projections in the sheet, the arrangement of dies and punches being such that no straight line can be drawn across the region of the circular dies without intersecting at least two of them.