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 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 invention relates to resin compositions, fiber reinforced polymeric structures and electromagnetic induction processes for making same. Such magnetic induction processes are pulsed processes that can be optionally coupled with cooling steps between pulses. The aforementioned fiber reinforced polymeric structures can take forms that include, but are not limited to, pipes; pressure vessels, including rocket motor cases and fire extinguishers; golf club shafts; tennis and badminton racquets; skis; snowboards; hockey sticks; fishing rods; bicycle frames; boat masts; oars; paddles; baseball bats; and softball bats. In addition, such fiber reinforced polymeric structures can be supplemented with other materials, such as a rocket propellant, to form articles, for example, a rocket motor.

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 cryogenic storage tank including a first metallic end piece having a first structured connection area on its outer surface, a second metallic end piece having a second structured connection area on its outer surface, a hollow body extending between the first structured connection area and the second structured area. The hollow body is formed of a fiber reinforced polymer-based composite, a first metallic clamp having a third structured connection area and a second metallic clamp having a fourth structured connection area. The hollow body is arranged between and in intimate contact with the first structured connection area of the first metallic end piece and with the third structured connection area of the first metallic clamp and is arranged between and in intimate contact with the second structured connection area of the second metallic end piece and with the fourth structured connection area of the second metallic clamp.

A pressure vessel includes a liner including a cylindrical body and a dorm portion continuous with at least one end of the body in an axial direction and includes a reinforced fiber sheet covering an outer side of the liner and made of fabric. The reinforced fiber sheet includes first yarns arranged on the body and the dorm portion such that yarn main axes of the first yarns extend in the circumferential direction of the liner and second yarns arranged on the body and the dorm portion such that yarn main axes of the second yarns extend in the axial direction of the liner. A total number of the first yarns or the second yarns that exist per unit length in the axial direction of the liner is smaller in the dorm portion than in the body.

A method for manufacturing a high-pressure tank including a liner that stores gas and a reinforcing layer made of a fiber-reinforced resin and covering an outer surface of the liner includes: a first step of forming a cylinder member made of the fiber-reinforced resin; a second step of forming two dome members made of the fiber-reinforced resin; and a third step of forming a reinforcing body that is the reinforcing layer by joining both end portions of the cylinder member and end portions of the two dome members, respectively. The first step includes forming the cylinder member by winding a release material around a mandrel and winding the fiber-reinforced resin on the release material.

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.

A hollow molded article having a joining site where two or more split objects are welded by plastic welding and comes into contact with pressurized hydrogen, wherein an average spherulite size in a portion which is 500 μm deep inside from a surface of the hollow molded article is 20 μm or less, and a tensile strength of a test piece containing the joining site of the hollow molded article is 80% or more based on a tensile strength of a test piece not containing the joining site of the hollow molded article.

Provided is a method for manufacturing a fiber reinforced resin molded article capable of effectively reducing the occurrence of a preform with poor resin impregnation, and such a manufacturing device thereof. After it is detected that a predetermined amount (the same amount) of resin has been individually poured into a plurality of cavities provided in a mold, the fiber layers of preforms are impregnated (compressively filled) with resin. Pressure sensors for detecting a resin injection amount are used. When closing runners, a small gap is formed in the runners.