A liner includes dome sections having outer surfaces along an uniform stress surface at both ends in an axial direction, and nozzles are mounted on the dome section by introducing nozzle flanges into pedestal sections of apexes of the dome sections. Then, ring-shaped caps having the same linear expansion coefficient as the liner and inner surfaces in a curved surface shape of outer surfaces of the dome sections and the nozzle flanges are mounted on boundary portions between the nozzle flanges and the pedestal sections. In forming a fiber layer after that, a helical winding layer is formed first by winding a fiber bundle disposed at the dome sections to cover the dome sections while including the nozzle flanges.

A method for producing a high-pressure tank capable of winding a reinforcing fiber bundle around a liner without deteriorating tank performance. The method for producing a high-pressure tank by winding a resin-impregnated strip-shaped reinforcing fiber bundle around a rotating liner so as to form a fiber-reinforced resin layer on the outer surface of the liner includes while winding the strip-shaped reinforcing fiber bundle around the liner, concurrently winding another bundle of fibers narrower than the strip-shaped reinforcing fiber bundle around the liner so as to cross the strip-shaped reinforcing fiber bundle.

A pressure vessel includes: a liner made of a resin and configured to store a pressurized fluid; and a reinforcing layer made of a fiber-reinforced resin provided around an outer peripheral surface of the liner. The liner includes a body portion having a tubular shape and a pair of side-end portions each having a domical shape. One of the side-end portions extends continuously from one of two ends of the body portion, and the other one of the side-end portions extends continuously from the other one of the two ends of the body portion. The liner includes a restriction portion provided at a center of the liner in an axial direction of the body portion. The restriction portion is configured to restrict displacement of the reinforcing layer in the axial direction.

A pressure vessel includes a polymeric liner defining a fluid containment cavity and having an opening defining a port aperture extending between an inner surface and an outer surface of the polymeric liner and a rigid ring element is embedded within the polymeric liner and surrounding the port aperture. A metallic port element is disposed on the outer surface of the polymeric liner and fixed to the rigid ring element. A fiber composite material is disposed about the outer surface of the polymeric liner.

A high-pressure tank which is capable of improving the strength of a connecting part between a cylindrical part and a dome part is provided. A high-pressure tank 10 according to the present invention comprises: a liner 20 having a cylindrically-shaped cylindrical part 20a and hemispherically-shaped dome parts 20b which are continuous with both ends of the cylindrical part 20a; and a reinforcing layer 30 including a fiber bundle which is hoop-wound around the cylindrical part 20a of the liner 20 and a fiber bundle which is helically wound around the dome parts 20b thereof. An outer diameter of the end of the cylindrical part 20a is smaller than an outer diameter of a portion of the cylindrical part 20a which excludes the end.

A method for manufacturing a high-pressure tank including a reinforcing layer in which rims of both ends of a tubular member and rims of a pair of dome members are joined to overlap each other in a radial direction includes producing the dome members and producing the tubular member. The producing of the dome members includes producing a wound body on a mandrel, curing a resin contained in the wound body, shaving the wound body after the resin is cured to reduce, toward a split line, thicknesses of the rims of the dome members to be obtained by splitting the wound body, splitting the shaved wound body into the dome members by cutting the wound body along the split line, and demolding the dome members from the mandrel.

A manufacturing method for manufacturing a reinforced layer constituting a high-pressure tank includes: a first forming step of forming a cylindrical pipe portion and extending in an axial direction of the high-pressure tank, the pipe portion including a first end portion including a first end and a second end portion including a second end, the pipe portion being formed to have a first stepped portion such that the first stepped portion projects outwardly at a position distanced from the first end in the axial direction by a first distance; a first placing step of placing the first end inside a first dome portion by moving at least either of the first dome portion and the pipe portion until a first bottom end portion of the first dome portion abuts with the first stepped portion; and a first joining step of joining the pipe portion to the first dome portion.

A high-pressure tank includes a container main body (10) constituted of a body (11) and dome portions (12) disposed on both ends of the body, and a reinforcing layer (20) formed such that a fiber member is wound around an outer periphery of the container main body. The reinforcing layer includes a hoop winding layer (40) formed by hoop winding that winds the fiber member such that a winding angle is approximately perpendicular to a central axis of the body, and a high helical winding layer (30) formed by high helical winding that winds the fiber member such that a winding angle is inclined with respect to the central axis compared with the hoop winding, and the high helical winding layer extends to the dome portion. The high helical winding layer includes a thick portion having a thickness at an outer side part of a boundary position between the body and the dome portion, which thickness is thicker than a thickness at a part positioned on the body. The hoop winding layer is formed from the body to the dome portion where the thick portion is formed, as a layer at an outer diameter side of the high helical winding layer.

The present invention is directed to a reinforcement method for a cylindrical high-pressure tank reinforced by FRP prepreg bandage, totally. For that purpose, this invention developed the manufacturing process for the internal metallic tank assembly where its diameter is comparatively large. It is effective for lightening weight of a high-pressure tank.

A high-pressure tank includes a first reinforcing layer and a second reinforcing layer. The first reinforcing layer is a layer obtained by joining dome members to respective end portions of a cylinder member, the dome members being a pair, and an inner peripheral surface of the cylinder member is exposed to a storage space that stores gas. A first resin layer covers the cylinder member between the first reinforcing layer and the second reinforcing layer. The first resin layer is less permeable to the gas in a thickness direction than the first reinforcing layer.