Pneumatic means for production of molded structures

摘要: Pneumatic means comprising a hollow mandrel or tube having secured around its outer surface along the length thereof according to one embodiment, flexible open-cell polyurethane foam sleeve and an skin formed of non-permeable plastic such as vinyl adhesively sleeve, air passages for communication between interior resulting assembly being positioned in mold production cored structural panels. In operation tool is placed under pressure expanded force outwardly during pouring setting construction material, e.g., cement cement-polymer composition mold, after subjected reduced vacuum withdraw from set composition, form molded panel, facilitate removal thereby forming material panel. Also included feature, pneumatic bellows arrangement external flexible, rubber, corrugated member, member permeable open-cell, polyurethane, foam, tensioning means, said inflatable applying contact, honeycomb, mounted on bellows, against casting which can be deflated associated members following panel construction. included, providing combination plurality both assemblies provision containing surfaces predetermined, smooth textured, configuration.