METHOD FOR FABRICATING COMPOSITE PRESSURE VESSELS AND PRODUCTS FABRICATED BY THE METHOD

摘要

A process for fabricating a composite vessel includes the steps of: A) preforming (e.g., by winding fiber and at least one thermoplastic substance onto a thermoplastic liner) a thermoplastic shell which has at least one opening for access to the interior; B) extruding a circular cross section of a fluid parison of thermoplastic material (which preferably is chosen to have a melting point lower than that of the thermoplatic shell) into the interior o f the thermoplastic shell through the opening; C) in a mold, applying at least one force (such as gas under pressure) which tends to urge the fluid parison toward the interior walls of the thermoplastic shell (which may be preheated prior to introduction into the mold) such that the fluid parison imparts hea t to the thermoplastic shell; D) continuing step C) until the thermoplastic shell and the fluid parison consolidate to form a composite vessel; E) cooli ng the vessel until it is solidified; and F) removing the vessel from the mold. For some composite vessels, prior to step C), an insert may be introduced in to the interior of the parison and positioned in alignment with the opening in the thermoplastic shell such that the insert is rendered integral with the composite vessel during step D). Suitable thermoplastic materials include polyethylene, polypropylene, polybutylene terephthalate and polyethylene terephthalate. The resulting composite vessel exhibits superior mechanical a nd aesthetic properties.