A multilayer structure for storing hydrogen, including, from the inside, at least one sealing layer and at least one composite reinforcement layer, an innermost composite reinforcement layer being welded to an outermost adjacent sealing layer, the sealing layers being a composition predominantly of: at least one semi-crystalline polyamide thermoplastic polymer P1i, i=1 to n, n being the number of sealing layers, excluding an amide polyether block (PEBA), up to 50% by weight of impact modifier relative to the total weight of the composition, up to 1.5% by weight of plasticizer relative to the total weight of the composition, and at least one of the composite reinforcement layers of a fibrous material in the form of continuous fibers, which is impregnated with a composition predominantly of at least one semi-crystalline polyamide polymer P2j, j=1 to m, m being the number of reinforcement layers.

A bladder-type pressure tank includes an outer shell, a bladder, a nozzle, and an elbow pipe. The outer shell includes a liner and a glass-fiber layer covering the outer surface of the liner. The liner includes polyethylene (PE). The liner further includes a chamber, a first opening, and a second opening. The bladder is disposed in the chamber. In an inflated state of the bladder, a gap is formed between the inflated bladder and the inner surface of the liner. The bladder includes polyurethane (PU). The nozzle is integrated with the bladder, and is disposed in the first opening and seals the first opening. The elbow pipe includes a first end and a second end. The first end of the elbow pipe is disposed in the second opening and communicates with the chamber; and the second end of the elbow pipe is configured to connect to a pipeline.

A pressure vessel assembly incudes a pressure vessel and a gas density gauge. The pressure vessel includes a vessel wall defining an interior cavity. The gas density gauge includes a parallel plate capacitor having a pair of plates. Opposing surfaces of the plates are separated by a distance across an open gap. A capacitance of the capacitor is related to a density of a gas within the open gap.

To suppress the degradation of sealing property of a pressure vessel and the deterioration of a sealing member, and to reduce the workload and cost of manufacture, a blow molding device includes a pair of molds configured to be clamped to sandwich a parison from both lateral sides, and a blow pin configured to form a neck portion together with the molds. The blow pin includes a blow pin body portion having an outer circumferential surface of a shape corresponding to an inner circumferential surface of the neck portion, and a ring portion forming an annular recess portion between the blow pin body portion and the ring portion to form an outer circumferential surface of a tip portion of the neck portion, which is a smooth surface without any parting line.

Method for preparing a hydrogen tank including at least one sealing layer of a composition including at least one polyamide P1, and at least one base in order to provide the tank with at least one opening, wherein the method includes: providing of at least one base, the at least one base being covered by at least one layer of a composition including at least one adhesion primer; preparing the at least one sealing layer; fastening the at least one base to the at least one sealing layer.

A plastic tank liner for the storage of a pressurized fluid includes: two ends; two elongated cylindrical sections, the two cylindrical sections having different diameters; and one connecting section connecting the two cylindrical sections. The connecting section has a concave portion connected to the cylindrical section of smaller diameter, and a convex portion adjacent to the cylindrical section of larger diameter. The convex portion has an isotensoid shape. Two convex domes are located on both ends of the plastic tank liner so that each of the domes is connected to a different cylindrical section.

A multilayer structure for transporting, distributing and storing hydrogen including, from the inside to the outside, a sealing layer and at least one composite reinforcement layer, the sealing layer including from the inside to the outside: a layer of a composition including: a short-chain polyamide thermoplastic polymer, more than 15% and up to 50% by weight of impact modifier, or including: a semi-crystalline long-chain polyamide thermoplastic polymer, up to 50% by weight of impact modifier, up to 3% by weight of plasticizer; a hydrogen barrier layer; a layer of a composition including: a short-chain polyamide thermoplastic polymer, more than 15% and up to 50% by weight of impact modifier, or including: a semi-crystalline long-chain polyamide thermoplastic polymer, up to 50% by weight of impact modifier, up to 3% of weight of plasticizer, the innermost composite reinforcement layer being wound around the sealing layer.

The present disclosure provides a carbon-fibre composite high-pressure hydrogen storage tank and a manufacturing process thereof. The hydrogen storage tank includes a tank body, wherein a gas guide port is formed in one side of the tank body, a reinforcing member for improving the strength of the tank body is arranged in an inner cavity of the tank body, a side end of the reinforcing member is fixedly connected to an inner wall of the tank body, and the tank body and the reinforcing member are all made of the carbon-fibre composite. The present disclosure can improve the whole strength and rigidity of the hydrogen storage tank and ensure the safer and more reliable hydrogen storage tank under a high pressure.

A liner configuring member configuring a liner includes a main body section which is configured from a resin material and has both ends opened. That is, both ends of the main body section are, respectively, a first open end and a second open end. There is provided in a vicinity of the first open end a first flange section where a first annular recess is formed by a first bottom section and a first side section. On the other hand, there is provided in a vicinity of the second open end a second flange section where a second annular recess is formed by a second bottom section and a second side section.

A high-pressure vessel that includes a cylinder, at least one half-shell, and a substantially rotationally symmetrical insert member. The cylinder, forming a middle region of the high-pressure vessel, is composed of a multilayer composite plastic having a first barrier layer. The at least one half-shell is formed at an axial end of the cylinder, and is composed of a multilayer composite plastic having a second barrier layer. The substantially rotationally symmetrical insert member has a foot member at an end thereof which faces an interior of the high-pressure vessel. The foot member has a diameter that is greater than a diameter of a middle region of the insert member. The foot member is configured to substantially form a hollow cone or hollow cylinder and at least a first groove or recess filled with the multilayer composite plastic of the at least one half-shell, and which is configured to extend around at least in certain portions on an inner circumference of the foot member.