METHOD & APPARATUS FOR MOLDING A HOLLOW OBJECT

摘要

A method and apparatus for open molding a one-piece hollow object involves an inflatable bladder having a predetermined shape when inflated fo r use as a male mold. Once inflated to a predetermined pressure, fiber reinforced plastic is applied to an outer surface thereof and allowed to cure. Once hardened, t he fiber reinforced material defines rigid walls of the hollow object and the bladder is deflated and removed from within the object. The bladder is rotated about a horizonta l axis during application and curing to allow access to all parts of the bladder an d prevent sagging of the materials applied thereto. During application and curing, a relief valve prevents excessive increase in pressure levels within the bladder.