A method for manufacturing a high pressure tank includes a step of forming a reinforcing pipe portion including a straight pipe portion and reduced-diameter portions, a step of forming reinforcing dome portions, a step of forming a joined body by joining the reinforcing pipe portion and the reinforcing dome portions, and a step of forming an outer helical layer on an outer face of the joined body. The reinforcing dome portions are disposed with opening ends of the reinforcing dome portions positioned on outer faces of the reduced-diameter portions of the reinforcing pipe portion.

Provided is a liner for a pressure vessel, the liner being constituted from a fiber-reinforced composite material containing a cured product of a thermosetting resin or a thermosetting resin composition, and continuous reinforcing fibers. Also provided is a high-pressure gas storage tank provided with the liner.

A method and apparatus for forming a pressure vessel liner are disclosed. One method includes forming an extruded tube by extruding a parison through a die and a mandrel and forming main body sections and return line sections in the extruded tube according to a first pattern. A cross-sectional area of the return line sections is smaller than a cross-sectional area of the main body sections. The method further includes changing the pattern according to which the main body sections and the return line sections are formed from the first pattern to a second pattern without stopping the forming of the extruded tube and forming the main body sections and the return line sections in the extruded tube according to the second pattern.

In the vicinity of an opening end of a first liner constituent member and a second liner constituent member made of a resin material, a flange portion is formed. After end surfaces of the opening end are abutted and joined to each other, the flange portion is removed in such a way that a part of a bottom portion remains. The remaining amount of protrusion is set such that the joint strength of a joint portion is not less than the tensile strength of the resin material or not less than the cohesion failure strength of the joint portion.

A method for manufacturing a high pressure tank includes a step of forming a reinforcing pipe portion including a straight pipe portion and reduced-diameter portions, a step of forming reinforcing dome portions, a step of forming a joined body by joining the reinforcing pipe portion and the reinforcing dome portions, and a step of forming an outer helical layer on an outer face of the joined body. The reinforcing dome portions are disposed with opening ends of the reinforcing dome portions positioned on outer faces of the reduced-diameter portions of the reinforcing pipe portion.

A method for manufacturing a composite pressurized-fluid vessel including winding a first polyolefin resin-based tape thereby forming a first layer of the vessel, depositing an intermediate second layer on the first layer, consisting of a material having variable permeability properties depending on the temperature and permeability below a pre-determined temperature threshold and non-permeability above the temperature threshold, winding a second resin-based tape on the intermediate second layer thereby forming a third layer, and cooling the intermediate second layer to a temperature below the temperature threshold while the first and third layers are each kept at a temperature above the melting temperature of their resin. Wherein the tape forming the third layer is based on a different resin from the first layer and during the step of depositing the intermediate second layer.

The present disclosure provides a high-efficiency filament helical winding device, which includes a frame body and a plurality of multi-filar guides. The frame body is provided with a through-hole, the plurality of multi-filar guides distributed in a circumference along a center of the through-hole are rotationally connected to the frame body and filament is extended out from each multi-filar guide in the plurality of multi-filar guides, and the frame body is provided with a first driving mechanism that drives each multi-filar guide to rotate.

A polar end ring mechanism for use with composite pressure vessels. The end ring is designed to support a pressure vessel during its formation via filament winding. The end ring helps define an opening at one of the polar ends of a tank. Spikes positioned along a portion of the end ring help prevent rotation or translation of the tank during formation and provide an improved mechanical lock with the tank body. A cap may then be secured to the polar end ring after formation in order to close the pressure vessel.

A cylindrical winding body is formed by winding continuous fibers impregnated with a first thermosetting resin in a circumferential direction, and the first thermosetting resin in the winding body is thermally cured. A pair of dome members is joined to both end portions of the cylinder member. A fiber bundle impregnated with a second thermosetting resin is helically wound around the joined member over the dome members, and the second thermosetting resin in the wound fiber bundle is thermally cured. A thermosetting resin containing a main agent and a granular solid curing agent is used as the first thermosetting resin, the main agent including a resin precursor and the solid curing agent chemically bonding molecules of the resin precursor together.

A high-pressure tank, a manufacturing method for a high-pressure tank, and a manufacturing device for a high-pressure tank capable of simplifying a shape of a metal fitting and performing high-speed FW molding without causing an idle rotation of the metal fitting or a deformation of a liner, for example, when performing the high-speed FW molding are provided. A high-pressure tank includes a liner, a reinforcing fiber layer, and a metal fitting. The reinforcing fiber layer is formed on an outer peripheral surface of the liner. The metal fitting is attached to the liner. The liner includes a liner main body and a protrusion part is provided in a part (cylindrical part) of the liner main body. The protrusion part is formed to protrude in a direction moving radially inward from the cylindrical part and to be fittable to a rotating shaft.