ISO 11515:2022

Gas cylinders — Refillable composite reinforced tubes of water capacity between 450 l and 3000 l — Design, construction and testing

This document specifies the minimum requirements for the materials, design, construction and performance testing of — Type 2 hoop-wrapped composite tubes, — Type 3 fully-wrapped composite tubes, and — Type 4 fully-wrapped composite tubes with water capacities between 450 l and 3 000 l for storage and conveyance of compressed or liquefied gases with test pressures up to and including 1 600 bar[1] and a design life of at least 15 years. This document is applicable to expected service temperatures between −40 °C and +65 °C. NOTE Type 4 tubes manufactured and tested to this document are not intended to contain toxic, oxidizing or corrosive gases. This document is applicable to tubes with composite reinforcement of carbon fibre or aramid fibre or glass fibre (or a mixture thereof) in a matrix. [1] 1 bar = 0,1 MPa = 105 Pa; 1 MPa = 1 N/mm2.

Bouteilles à gaz — Tubes composites renforcés rechargeables d'une capacité de 450 l à 3000 l — Conception, construction et essais

General Information

• Status: Published
• Publication Date: 23-Aug-2022
• ICS: 23.020.35 - Gas cylinders
• Technical Committee: ISO/TC 58/SC 3 - Cylinder design
• Drafting Committee: ISO/TC 58/SC 3/WG 32 - Refillable composite reinforced tubes of water capacity between 150l and 3 000l – Design, construction and testing
• Current Stage: 6060 - International Standard published
• Start Date: 24-Aug-2022
• Due Date: 17-May-2022
• Completion Date: 24-Aug-2022

Relations

• Revises: ISO 11515:2013 - Gas cylinders — Refillable composite reinforced tubes of water capacity between 450 L and 3000 L — Design, construction and testing
• Effective Date: 23-Apr-2020
• Revises: ISO 11515:2013/Amd 1:2018 - Gas cylinders — Refillable composite reinforced tubes of water capacity between 450 L and 3000 L — Design, construction and testing — Amendment 1
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 11515
Second edition
2022-08
Gas cylinders — Refillable composite
reinforced tubes of water capacity
between 450 l and 3000 l — Design,
construction and testing
Bouteilles à gaz — Tubes composites renforcés rechargeables d'une
capacité de 450 l à 3000 l — Conception, construction et essais
Reference number
ISO 11515:2022(E)
© ISO 2022

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ISO 11515:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
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ISO copyright office
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Website: www.iso.org
Published in Switzerland
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ISO 11515:2022(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols . 5
5 Inspection and testing .6
6 Materials . 6
6.1 Liner materials . 6
6.2 Composite overwrap . 7
7 Design and manufacture . 7
7.1 General . 7
7.2 Design submission . 8
7.3 Manufacturing . 9
8 Type approval procedure .10
8.1 General . 10
8.2 Prototype tests . . 10
8.3 New design . 11
8.4 Design variants .12
8.5 Type approval test procedures and criteria . 17
8.5.1 General . 17
8.5.2 Hydraulic proof pressure test . 17
8.5.3 Hydraulic volumetric expansion test . 17
8.5.4 Liner burst test . 18
8.5.5 Tube burst test. 18
8.5.6 Ambient cycle test . 19
8.5.7 Environmental cycle test . 20
8.5.8 Flaw test . 21
8.5.9 Blunt impact test . 23
8.5.10 Fire resistance test . 24
8.5.11 Neck strength test . 26
8.5.12 Leak test . 27
8.5.13 Accelerated stress rupture test . . 27
8.5.14 Permeability test .28
8.5.15 Gas cycle test .28
8.5.16 Coatings test .29
8.5.17 Salt spray test . 30
8.5.18 Acid environment test .30
8.5.19 Vacuum test . 31
8.5.20 High velocity impact (gunfire) test . 31
8.5.21 Glass transition temperature test . 32
8.5.22 Resin shear strength test . 32
8.6 Failure of type approval tests . 32
9 Inspection and testing at time of manufacture .32
9.1 Liners for Type 2 and Type 3 tubes . 32
9.2 Failure of load-sharing liner batch tests . 33
9.3 Liners for Type 4 tubes. 33
9.4 Failure of non-load sharing liner batch tests .34
9.5 Overwrap materials .34
9.6 Composite tube. 35
9.7 Failure of batch tests . 35
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ISO 11515:2022(E)
10 Tube marking .36
10.1 General .36
10.2 Additional marking.36
Annex A (informative) Example of a design approval certificate .37
Annex B (informative) Example of a test report.38
Annex C (normative) Ultrasonic inspection for seamless steel liners and metal tubing .40
Annex D (informative) Guidance for calculating permeation rates when using trace gases . 44
Bibliography .45
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ISO 11515:2022(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/
iso/foreword.html.
This document was prepared by Technical ISO/TC 58, Gas cylinders, Subcommittee SC 3, Cylinder design.
This second edition cancels and replaces the first edition (ISO 11515:2013), which has been technically
revised. It also incorporates the Amendment, ISO 11515:2013/Amd.1:2018. The main changes are as
follows:
— the references have been updated;
— a resin shear strength test was added to the document and to Tables 2, 3 and 4,
— in 8.5.10, fire resistance test, the procedure has been changed to make the test more consistent;
— the criteria in 8.5.10.3 has been revised;
— in 8.5.15, gas cycle test, a new procedure has been added for the test to have a lower number of
cycles but with a significant hold time at pressure.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 11515:2022(E)
Introduction
This document provides a specification for the design, manufacture, inspection and testing of composite
tubes for worldwide usage. The objective of this document is to balance design and economic efficiency
against international acceptance and universal utility.
This document aims to eliminate the concern about climate, duplicate inspection and restrictions
currently existing because of a lack of definitive International Standards and should not be construed
as reflecting on the suitability of the practice of any nation or region.
[1]
This document has been written so that it is suitable to be referenced in the UN Model Regulations .
Composite tubes can be used alone or in batteries to equip trailers or skids (ISO modules) or multiple
element gas containers (MEGCs) for the transportation and distribution of gases. This document does
not include consideration of any additional stresses that can occur during service or transport (e.g.
torsional/bending stresses). However, it is important that the stresses associated with mounting the
tube are considered by the assembly manufacturer and the tube manufacturer.
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INTERNATIONAL STANDARD ISO 11515:2022(E)
Gas cylinders — Refillable composite reinforced tubes
of water capacity between 450 l and 3000 l — Design,
construction and testing
1 Scope
This document specifies the minimum requirements for the materials, design, construction and
performance testing of
— Type 2 hoop-wrapped composite tubes,
— Type 3 fully-wrapped composite tubes, and
— Type 4 fully-wrapped composite tubes
with water capacities between 450 l and 3 000 l for storage and conveyance of compressed or liquefied
1)
gases with test pressures up to and including 1 600 bar and a design life of at least 15 years.
This document is applicable to expected service temperatures between −40 °C and +65 °C.
NOTE Type 4 tubes manufactured and tested to this document are not intended to contain toxic, oxidizing or
corrosive gases.
This document is applicable to tubes with composite reinforcement of carbon fibre or aramid fibre or
glass fibre (or a mixture thereof) in a matrix.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 306, Plastics — Thermoplastic materials — Determination of Vicat softening temperature (VST)
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 3341, Textile glass — Yarns — Determination of breaking force and breaking elongation
ISO 4624:2016, Paints and varnishes — Pull-off test for adhesion
ISO 6506-1, Metallic materials — Brinell hardness test — Part 1: Test method
ISO 6508-1, Metallic materials — Rockwell hardness test — Part 1: Test method
ISO 7225, Gas cylinders — Precautionary labels
ISO 7866, Gas cylinders — Refillable seamless aluminium alloy gas cylinders — Design, construction and
testing
ISO 9227:2017, Corrosion tests in artificial atmospheres — Salt spray tests
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
5 2
1) 1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .
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ISO 11515:2022(E)
ISO 9809-1, Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and
tubes — Part 1: Quenched and tempered steel cylinders and tubes with tensile strength less than 1 100 MPa
ISO 9809-2, Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and
tubes — Part 2: Quenched and tempered steel cylinders and tubes with tensile strength greater than or
equal to 1 100 MPa
ISO 9809-3, Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and
tubes — Part 3: Normalized steel cylinders and tubes
ISO 10286, Gas cylinders — Vocabulary
ISO 10618, Carbon fibre — Determination of tensile properties of resin-impregnated yarn
ISO 11114-1, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 1:
Metallic materials
ISO 11114-2, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 2:
Non-metallic materials
ISO 11120, Gas cylinders — Refillable seamless steel tubes of water capacity between 150 l and 3000 l —
Design, construction and testing
ISO 13341, Gas cylinders — Fitting of valves to gas cylinders
ISO 13769, Gas cylinders — Stamp marking
ISO 14130, Fibre-reinforced plastic composites — Determination of apparent interlaminar shear strength
by short-beam method
ASTM D522, Standard Test Methods for Mandrel Bend Test of Attached Organic Coatings
ASTM D1308, Standard Test Method for Effect of Household Chemicals on Clear and Pigmented Organic
Finishes
ASTM D2344, Standard Test Method for Short-Beam Strength of Polymer Matrix Composite Materials and
Their Laminates
ASTM D2794, Standard Test Method for Resistance of Organic Coatings to the Effects of Rapid Deformation
(Impact)
ASTM D3170, Standard Test Method for Chipping Resistance of Coatings
ASTM D7269, Standard Test Methods for Tensile Testing of Aramid Yarns
ASTM E1356, Standard Test Method for Assignment of the Glass Transition Temperatures by Differential
Scanning Calorimetry
ASTM G154, Standard Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of
Non-metallic Materials
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10286 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
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ISO 11515:2022(E)
3.1
aramid fibre
continuous filaments of aramid laid up in tow form, used for reinforcement
3.2
autofrettage
pressure application procedure which strains the metal liner (3.18) past its yield point sufficient to
cause permanent plastic deformation, and results in the liner having compressive stresses and the
fibres having tensile stresses when at zero internal gauge pressure
3.3
batch
set of homogeneous items or material
Note 1 to entry: The number of items in a batch can vary according to the context in which the term is used.
3.4
batch of load-sharing liners
quantity of liners (3.18) of the same nominal diameter, length, thickness and design, made successively
from the same material cast (heat) and processed in the same heat treatment equipment (i.e. a
continuous furnace process or a single furnace charge) using the same heat treatment parameters
3.5
batch of non-load sharing liners
quantity of non-load sharing liners of the same nominal diameter, length, thickness and design, made
successively and subjected to the same continuous manufacturing process
3.6
batch of metal bosses
quantity of metal bosses of the same nominal diameter, length, thickness and design, made successively
from the same material cast (heat) and processed in the same heat treatment equipment using the same
heat treatment parameters
3.7
batch of composite tubes
quantity of up to 200 finished tubes (3.24) successively produced (plus finished tubes required for
destructive testing), of the same nominal diameter, length, thickness and design
Note 1 to entry: The batch (3.3) of finished tubes can contain different batches of liners, fibres and matrix (3.21)
materials.
3.8
burst pressure
highest pressure reached in a tube (3.24) or liner (3.18) during a burst test
3.9
carbon fibre
continuous filaments of carbon laid up in tow form, used for reinforcement
3.10
composite overwrap
combination of fibres and matrix (3.21) used to reinforce the tube (3.24), including any barrier or
protective layers that are a permanent part of the design
3.11
dedicated gas service
service in which a tube (3.24) is used only with specified gas or gases
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ISO 11515:2022(E)
3.12
equivalent fibre
fibre from the same material family and similar properties to a fibre used in a previously prototype
tested tube (3.24)
3.13
equivalent liner
liner (3.18) manufactured from the same nominal raw materials, using the same process of manufacture
and having the same physical structure and the same nominal physical properties (within ±5 %) of the
approved liner design
3.14
equivalent matrix
resin matrix (3.21) from the same chemical family and similar properties to the resin matrix used in a
previously prototype tested tube (3.24)
3.15
exterior coating
layers of material applied to the tube (3.24) as protection or for cosmetic purposes
Note 1 to entry: The coating can be transparent or opaque.
3.16
glass fibre
continuous filaments of glass laid up in tow form, used for reinforcement
3.17
leak
−3
escape of gas at a rate greater than 5 × 10 mbar·l/s through a defect rather than permeation
3.18
liner
inner portion of the composite tube (3.24), whose purpose is both to contain the gas and transmit the
gas pressure to the fibres
3.19
load-sharing liner
liner (3.18) that has a burst pressure (3.8) greater than or equal to 5 % of the nominal burst pressure of
the finished composite tube (3.24)
3.20
non-load-sharing liner
liner (3.18) that provides no load sharing for the finished composite tube (3.24)
3.21
matrix
material that is used to bind and hold the fibres in place
3.22
minimum design burst pressure
minimum burst pressure (3.8) specified by the manufacturer
3.23
representative composite tube
shorter tube (3.24) with the same nominal diameter, and manufactured using the same materials and
manufacturing technique, and using a representative wrapping pattern (same number of strands and
same number of layers) so as to represent an equivalent stress compared to a full-scale prototype
3.24
tube
transportable pressure receptacle with a water capacity exceeding 150 l
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ISO 11515:2022(E)
3.25
tubing
hollow cylindrical body of metal or other material, used for conveying or containing liquids or gases
3.26
Type 2 tube
hoop-wrapped tube (3.24) with a load-sharing liner (3.19) and composite reinforcement on the
cylindrical portion only
3.27
Type 3 tube
fully wrapped tube (3.24) with a load-sharing liner (3.19) and composite reinforcement on both
cylindrical portion and dome ends
3.28
Type 4 tube
fully wrapped tube (3.24) with a non-load-sharing liner (3.20) and composite reinforcement on both
cylindrical portion and dome ends
3.29
glass transition temperature
T
g
temperature where a polymer substrate changes from a rigid glassy material to a soft (not melted)
material, usually measured in terms of the stiffness, or modulus
4 Symbols
p burst pressure of the finished tube bar
b
p test pressure bar
h
p maximum developed pressure at 65 °C bar
max
p working pressure bar
w
E notch length mm
T notch depth mm
S tube nominal wall thickness mm
W notch width mm
T glass transition temperature °C
g
N pressurization cycles to test pressure —
N pressurization cycles to maximum developed pressure —
d
y number of years of design life —
t nominal composite thickness —
L length of tube m
n viscosity of gas 1 μ centipoise
1
n viscosity of gas 2 μ centipoise
2
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ISO 11515:2022(E)
Q flow rate of gas 1 ACM/h
1
(actual cubic meters/
hour)
Q flow rate of gas 2 ACM/h
2
5 Inspection and testing
To ensure that the tubes conform to this document, they shall be subject to inspection and testing in
accordance with Clauses 6, 7, 8 and 9.
Tests and examinations performed to demonstrate conformity to this document shall be conducted
using instruments calibrated before being put into service and thereafter according to an established
programme.
NOTE Other requirements can apply in relevant national or regional regulations of the country (countries)
where the tubes are intended to be used.
6 Materials
6.1 Liner materials
6.1.1 Load-sharing liner materials shall conform in all relevant respects to the appropriate
International Standards:
a) seamless steel liners: ISO 9809-1, ISO 9809-2, ISO 9809-3 or ISO 11120, as appropriate;
b) seamless aluminium alloy liners: ISO 7866.
Relevant sections are those covering materials, thermal treatments, neck design, construction and
workmanship and mechanical tests. Design requirements are excluded since these are specified by the
manufacturer for the design of the composite tube (see 7.2.2).
6.1.2 The composite tube manufacturer shall verify that each new batch of materials has the
specified properties and qualities and shall maintain records so that the cast of material and the heat
treatment batch where applicable, used for the manufacture of each tube can be identified. A certificate
of conformance, from the liner material manufacturer is considered acceptable for the purposes of
verification.
6.1.3 The liner shall be manufactured from a metal or alloy suitable for the gas to be contained in
accordance with ISO 11114-1, if applicable.
6.1.4 When a neck ring is provided, it shall be of a material compatible with that of the tube and shall
be securely attached by a method appropriate to the liner material.
6.1.5 Non-load-sharing liner materials shall conform in all relevant respects to the appropriate
standards, as follows:
a) The liner (including metal boss) shall be manufactured from a material suitable for the gas to be
contained in accordance with ISO 11114-1 and ISO 11114-2 or demonstrated and documented by
suitable testing.
b) Metal bosses that are attached to a non-load sharing liner shall fulfil the type approval testing
requirements of this document.
c) The tensile yield strength and ultimate elongation of pla
...