Patent ID: 6074595
Filing Date: 2000-06-13
Classification: B29C,B29K,B32B

Abstract:
A method of making tubular pressure vessels using polymer-impregnated fibrous material, which method comprises the steps of:providing a cylindrical mandrel of circular cross section,forming a barrier layer upon said mandrel by rotating said mandrel about its longitudinal axis while helically applying at least one wrapping of a first fibrous material, which fibrous material is impregnated and coated with a viscous polymer material containing two resin systems which are curable in different ways,effecting the curing of one of said two resin systems in said polymer material so as to form a stable drip-free barrier layer in the form of a thin tube on said mandrel, which thin tube will constitute the interior surface region of the completed pressure vessel,inspecting said stable barrier layer for the presence of imperfections such as would require quality control rejection or substantial repair upon discovery in a completed pressure vessel,after such inspection and optional repair of said barrier layer, forming a major portion of said pressure vessel sidewall in an exterior surrounding relationship to said barrier layer by applying multiple wrappings of a second fibrous material including long fibrous reinforcing strands which are impregnated and coated with the other of said two resin systems to create a tubular lay-up of desired thickness,curing said other resin system which is present throughout the entire thickness of said tubular lay-up to create a strong, rigid, fiber-reinforced polymeric tubular pressure vessel, andremoving said pressure vessel from said mandrel,whereby pressure vessels meeting ASME Section X code standards for vessels with integral fiber-reinforced resin sidewalls and having defect-free interior surfaces are efficiently manufactured.