Hollow reinforced resin mouldings - made by a double vacuum bag technique

摘要

Title mouldings are made by lay up on to either the inner or outer surfaces of a hollow mandrel and cladding the mandrel and the laid up materials between a pair of flexible bags which are then sealed together over the mouth of the mandrel before an excess press. is generated on the exposed surfaces of the bags. PRef. the air between the two bags is evacuated via a porous pipe laid along the length of the mandrel. Esp. suitable for mfg. e.g. pipe, ducts or hollow casings out of e.g. glass fibre reinforced polyester phenolic or epoxy resins, without involving complicated mech. or hydraulic consolidation mechanisms. Conforms readily to section profile variations without requiring a complementary solid press tool.