Scaffolding boards of phenolic foam in card or fabric sheath - can be produced for less cost than metal clad foam cored boards
Abstract
Abstract The parent patent described lightweight scaffolding planks comprising a hollow casing fabricated from thin sheet metal and filled with a rigid foam injected under pressure. This addition claims similar boards having a non-metallic casing, pref. made of multiply cardboard or woven matting coated or impregnated with resin. The ends of the board are enclosed and stiffened by rigid bars, pref. also covered with resin impregnated fabric. In an example, a board of 2.5 x 0.6 m and 8 cm thick with a cardboard cover has a flexural strength of 900-1000 kgf: a similar board only 5 cm thick but covered with woven glass cloth impregnated with polyester resin had a flexural strength of 1700-1800 kgf. Simpler and cheaper to make than equivalent boards with a metal cover.
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Bibliographic Details
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