ISO 11515 pdf download Gas cylinders — Refillable composite reinforced tubes of water capacity between 450 L and 3000 L — Design, construction and testing
aThe liner (including metal boss) shall be manufactured from a material suitable for the gas to becontained in accordance with ISO 11114-1 and ISO 11114-2.
bMetal bosses attached to a non-metallic liner shall fulfil the performance requirements of thisInternational Standard.
cThe tensile yield strength and ultimate elongation of plastic liner material shall be determined at-50 °C in accordance with ISO 527-2.The test results shall demonstrate the ductile properties ofthe plastic liner material at temperatures of -50 C or lower by meeting the values specified by themanufacturer.
dPolymeric materials from finished liners shall be tested in accordance with a method described inISO 306.The softening temperature shall be at least 100·C.
6.2.1 The overwrap filament materials shall be carbon fibre or aramid fibre or glass fibre (or anymixture thereof).
6.2.2The resin matrix shall be a polymer suited to the application, environment and intended life oftheproduct, e.g. epoxy or modified epoxy with amine or anhydride curing agent, vinyl esters and polyesters
6.2.3 The supplier of the filament material and the resin matrix system component materials shalprovide sufficient documentation for the composite tube manufacturer to be able to identify fuly thebatch of materials used in the manufacture of each tube
6.2.4 The composite tube manufacturer shall verify that each new batch of materials has the correctproperties and is of satisfactory quality, and maintain records from which the batch of materials usecfor the manufacture of each tube can be identified. A certificate of conformance from the materiamanufacturer is considered acceptable for the purposes of verification.
6.25 Batches of materials shall be identified and documented to the satisfaction of the inspector
6.2.6 The manufacturer shallensure there is no adverse reaction between theliner and thereinforcingfibre, e.g. by the application of a suitable protective coating to the liner prior to the wrapping process(if necessary).
NOTEGlass fibre reinforced composite tubes can be susceptible to chemical attack and degradation afterbeing in contact with aggressive acids (eg. battery acid).
7 Design and manufacture
7.11 A Type 2 composite tube shall comprise:
a) an internal metal liner with one or two openings along the central axis only, which carries all thelongitudinalload and part of the circumferentialload;
bthe liner, designed to withstand a burst pressure greater than 0,85 of the test pressure of thefinished tube.
ca composite overwrap formed by layers of continuous fibres in a matrix along the parallel portionsof the tube sidewall;