ISO 9809-4:2021
(Main)Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and tubes — Part 4: Stainless steel cylinders with an R m value of less than 1 100 MPa
Gas cylinders — Design, construction and testing of refillable seamless steel gas cylinders and tubes — Part 4: Stainless steel cylinders with an R m value of less than 1 100 MPa
This document specifies the minimum requirements for the materials, design, construction and workmanship, manufacturing processes, examinations and testing at time of manufacture for refillable, seamless, stainless steel gas cylinders with water capacities up to and including 150 l. It is applicable to cylinders for compressed, liquefied and dissolved gases with a maximum actual tensile strength, Rma, of less than 1 100 MPa. NOTE If so desired, cylinders of water capacity between 150 l and 450 l can be manufactured to be in full conformance to this document.
Bouteilles à gaz — Conception, construction et essais des bouteilles à gaz et des tubes rechargeables en acier sans soudure — Partie 4: Bouteilles en acier inoxydable ayant une valeur de Rm inférieure à 1 100 MPa
Le présent document spécifie les exigences minimales concernant le matériau, la conception, la construction et la mise en œuvre, les procédés de fabrication, les examens et les essais au moment de la fabrication des bouteilles à gaz rechargeables en acier sans soudure d’une contenance en eau inférieure ou égale à 150 l. Il s’applique aux bouteilles pour les gaz comprimés, liquéfiés et dissous ayant une résistance à la traction réelle, Rma, maximale inférieure à 1 100 MPa. NOTE Si cela est souhaité, les bouteilles d’une contenance en eau comprise entre 150 l et 450 l peuvent être fabriquées conformément au présent document.
General Information
Relations
Buy Standard
Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 9809-4
Second edition
2021-11
Gas cylinders — Design, construction
and testing of refillable seamless steel
gas cylinders and tubes —
Part 4:
Stainless steel cylinders with an R
m
value of less than 1 100 MPa
Bouteilles à gaz — Conception, construction et essais des bouteilles à
gaz et des tubes rechargeables en acier sans soudure —
Partie 4: Bouteilles en acier inoxydable avec une valeur R
m
inférieure à 1 100 MPa
Reference number
ISO 9809-4:2021(E)
© ISO 2021
---------------------- Page: 1 ----------------------
ISO 9809-4:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
© ISO 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 9809-4:2021(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 3
5 Inspection and testing .4
6 Materials . 4
6.1 General requirements . 4
6.2 Controls on chemical composition . 5
6.3 Heat treatment. 5
6.4 Cold working or cryoforming . 5
6.5 Failure to meet test requirements . 6
7 Design . 6
7.1 General requirements . 6
7.2 Design of cylindrical shell thickness . 6
7.3 Design of convex ends (heads and bases) . 7
7.4 Design of the concave base ends . 8
7.5 Neck design . 9
7.6 Foot rings . . 9
7.7 Neck rings . 9
7.8 Design drawing . 10
8 Construction and workmanship .10
8.1 General . 10
8.2 Wall thickness . 10
8.3 Surface imperfections . 10
8.4 Ultrasonic examination . 10
8.5 Out-of-roundness . 11
8.6 Mean diameter . 11
8.7 Straightness . 11
8.8 Verticality and stability . 11
8.9 Neck threads .12
9 Type approval procedure .12
9.1 General requirements . 12
9.2 Prototype test . 13
9.2.1 General requirements . 13
9.2.2 Pressure cycling test . 14
9.2.3 Base check . 14
9.2.4 Torque test for taper thread only . 15
9.2.5 Shear stress calculation for parallel threads . 15
9.3 Type approval certificate .15
9.4 Specific type approval/production tests for cylinders ordered in small quantities . 16
10 Batch tests . .16
10.1 General requirements . 16
10.2 Tensile test . 18
10.3 Bend test and flattening test . 19
10.3.1 Bend test . 19
10.3.2 Flattening test . . 20
10.3.3 Ring flattening test. 20
10.4 Impact test . 20
iii
© ISO 2021 – All rights reserved
---------------------- Page: 3 ----------------------
ISO 9809-4:2021(E)
10.5 Hydraulic burst test . 22
10.5.1 Test installation . .22
10.5.2 Test conditions . 23
10.5.3 Interpretation of test results . 24
10.6 Intergranular corrosion test .25
11 Tests/examinations on every cylinder .25
11.1 General . 25
11.2 Hydraulic test . 26
11.2.1 Proof pressure test .26
11.2.2 Volumetric expansion test . 26
11.3 Hardness test . 26
11.4 Leak test . 26
11.5 Capacity check . 27
12 Certification .27
13 Marking . .27
Annex A (normative) Description and evaluation of manufacturing imperfections and
conditions for rejection of seamless steel gas cylinders at the time of final
inspection by the manufacturer.28
Annex B (normative) Ultrasonic examination .43
Annex C (informative) Example of type approval certificate .49
Annex D (informative) Example of acceptance certificate .50
Annex E (informative) Example of shear strength calculation for parallel threads .52
Bibliography .54
iv
© ISO 2021 – All rights reserved
---------------------- Page: 4 ----------------------
ISO 9809-4:2021(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 Committee ISO/TC 58, Gas cylinders, Subcommittee SC 3,
Cylinder design.
This second edition cancels and replaces the first edition (ISO 9809-4:2014), which has been technically
revised. The main changes compared with the previous edition are as follows:
— update of Clause 5;
— clarification of Figure 3;
— clarification of 8.9;
— modification of 9.1, 9.2, 9.2.4 and Annex A;
— new subclause 9.2.5 for parallel threads;
— new subclause 9.4 for cylinders ordered in small quantities.
A list of all parts in the ISO 9809 series can be found on the ISO website.
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.
v
© ISO 2021 – All rights reserved
---------------------- Page: 5 ----------------------
ISO 9809-4:2021(E)
Introduction
This document provides a specification for the design, manufacture, inspection and testing of a
seamless stainless steel cylinder. The objective is to balance the design and economic efficiency against
international acceptance and universal utility.
ISO 9809 (all parts) aims to eliminate the concern about climate, duplicate inspections and restrictions
because of the lack of definitive International Standards.
[1]
This document has been written so that it is suitable to be referenced in the UN Model Regulations .
vi
© ISO 2021 – All rights reserved
---------------------- Page: 6 ----------------------
INTERNATIONAL STANDARD ISO 9809-4:2021(E)
Gas cylinders — Design, construction and testing of
refillable seamless steel gas cylinders and tubes —
Part 4:
Stainless steel cylinders with an R value of less than 1 100
m
MPa
1 Scope
This document specifies the minimum requirements for the materials, design, construction and
workmanship, manufacturing processes, examinations and testing at time of manufacture for refillable,
seamless, stainless steel gas cylinders with water capacities up to and including 150 l.
It is applicable to cylinders for compressed, liquefied and dissolved gases with a maximum actual
tensile strength, R , of less than 1 100 MPa.
ma
NOTE If so desired, cylinders of water capacity between 150 l and 450 l can be manufactured to be in full
conformance to this document.
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 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 3651-2, Determination of resistance to intergranular corrosion of stainless steels — Part 2:
Ferritic,austenitic and ferritic-austenitic (duplex) stainless steels — Corrosion test in media containing
sulfuric acid
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 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 9328-1, Steel flat products for pressure purposes — Technical delivery conditions — Part 1: General
requirements
ISO 9329-4, Seamless steel tubes for pressure purposes — Technical delivery conditions — Part 4: Austenitic
stainless steels
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 10286, Gas cylinders — Vocabulary
ISO 13341, Gas cylinders — Fitting of valves to gas cylinders
ISO 13769, Gas cylinders — Stamp marking
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10286 and the following apply.
1
© ISO 2021 – All rights reserved
---------------------- Page: 7 ----------------------
ISO 9809-4:2021(E)
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
batch
quantity of up to 200 cylinders, plus cylinders for destructive testing of the same nominal diameter,
thickness, length and design made successively on the same equipment, from the same cast of steel, and
subjected to the same heat treatment for the same duration of time
3.2
burst pressure
p
b
highest pressure reached in a cylinder during a burst test
3.3
cold working
process in which a cylinder is subjected to a pressure higher than the cylinder test pressure (3.11) to
increase the yield strength (3.12) of the steel
3.4
cryoforming
process where the cylinder is subjected to a controlled low-temperature deformation treatment that
results in a permanent increase in strength
3.5
design stress factor
F
ratio of the equivalent wall stress at test pressure, p , (3.11) to guaranteed minimum yield strength, R
h eg
3.6
quenching
hardening heat treatment in which a cylinder, which has been heated to a uniform temperature above
the upper critical point, Ac , of the steel, is cooled rapidly on a suitable medium
3
3.7
reject
action to set aside a cylinder (Level 2 or Level 3) that is not allowed to go into service
3.8
rendered unserviceable
cylinder that has been treated in such a way as to render it impossible for use
Note 1 to entry: Examples for acceptable methods to render cylinders unserviceable can be found in ISO 18119.
Any actions on cylinders rendered unserviceable are outside the scope of this document.
3.9
repair
action to return a rejected cylinder to a Level 1 condition
3.10
tempering
toughening heat treatment which follows quenching (3.6), in which the cylinder is heated to a uniform
temperature below the critical point, Ac , of the steel
1
2
© ISO 2021 – All rights reserved
---------------------- Page: 8 ----------------------
ISO 9809-4:2021(E)
3.11
test pressure
p
h
required pressure applied during a pressure test
Note 1 to entry: Test pressure is used for the cylinder wall thickness calculation.
3.12
yield strength
stress value corresponding to the 0,2 % proof stress or for austenitic steels in the solution-annealed
condition, 1 % proof stress
3.13
working pressure
settled pressure of a compressed gas at a uniform reference temperature of 15 °C in a full gas cylinder
4 Symbols
A percentage elongation after fracture
a calculated minimum thickness, in millimetres, of the cylindrical shell
a′ guaranteed minimum thickness, in millimetres, of the cylindrical shell
a guaranteed minimum thickness, in millimetres, of a concave base at the knuckle (see Figure 2)
1
a guaranteed minimum thickness, in millimetres, at the centre of a concave base (see Figure 2)
2
b guaranteed minimum thickness, in millimetres, at the centre of a convex base (see Figure 1)
c maximum permissible deviation, in millimetres, of burst profile for quenched and tempered
1
cylinders (see Figure 11)
c maximum permissible deviation, in millimetres, of the burst profile for cryoformed or solution-
2
annealed cylinders with less than 7,5 mm wall thickness (see Figure 12)
D nominal outside diameter of the cylinder, in millimetres (see Figure 1)
D diameter, in millimetres, of former (see Figure 6)
f
F design stress factor (variable)
H outside height, in millimetres, of the domed part (convex head or base end) (see Figure 1)
h outside depth (concave base end), in millimetres (see Figure 2)
L original gauge length, in millimetres, as defined in ISO 6892-1 (see Figure 5)
o
l overall length of the cylinder, in millimetres (see Figure 3)
n ratio of the diameter of the bend test former to the actual thickness of test piece, t
p measured burst pressure, in bar, above atmospheric pressure
b
5
NOTE 1 bar = 10 Pa = 0,1 MPa.
p hydraulic test pressure, in bar, above atmospheric pressure
h
p observed pressure when the cylinder starts yielding during the hydraulic burst test, in bar, above
y
atmospheric pressure
3
© ISO 2021 – All rights reserved
---------------------- Page: 9 ----------------------
ISO 9809-4:2021(E)
r inside knuckle radius, in millimetres (see Figures 1 and 2)
R actual value of the yield strength, in megapascals, as determined by the tensile test (see 10.2)
ea
R minimum guaranteed value of the yield strength (see 7.1.1), in megapascals, for the finished cylinder
eg
R actual value of the tensile strength, in megapascals, as determined by the tensile test (see 10.2)
ma
R minimum guaranteed value of the tensile strength, in megapascals, for the finished cylinder
mg
S original cross-sectional area of the tensile test piece, in square millimetres, in accordance with
o
ISO 6892-1
t actual thickness of the test specimen, in millimetres
t average cylinder wall thickness at the position of testing during the flattening test, in millimetres
m
u ratio of the distance between the knife edges or platens in the flattening test to the average
cylinder wall thickness at the position of the test
V water capacity of the cylinder, in litres
w width, in millimetres, of the tensile test piece (see Figure 5)
5 Inspection and testing
Assessment of conformity to this document shall take into account the applicable regulations of the
countries of use.
To ensure that cylinders conform to this document, they shall be subject to inspection and testing in
accordance with Clauses 9, 10 and 11.
Tests and examinations performed to demonstrate compliance with this document shall be conducted
using instruments calibrated before being put into service and thereafter according to an established
programme.
6 Materials
6.1 General requirements
6.1.1 Materials for the manufacture of gas cylinders shall fall within one of the following categories:
a) internationally recognized cylinder steels;
b) nationally recognized cylinder steels;
c) new cylinder steels resulting from technical progress.
For all categories, the relevant conditions specified in 6.2 and 6.3 shall be satisfied.
6.1.2 There is a risk of intergranular corrosion in austenitic and duplex stainless steels resulting
from hot processing which can cause sensitization of the steel (e.g. chromium depletion in the grain
boundary). Intergranular corrosion testing shall be carried out for such materials in accordance with
10.6.
6.1.3 The cylinder manufacturer shall establish the means to identify the cylinders with the cast of
steel from which they are made.
4
© ISO 2021 – All rights reserved
---------------------- Page: 10 ----------------------
ISO 9809-4:2021(E)
6.1.4 Grades of steel used for the cylinder manufacture shall be compatible with the intended gas
service, e.g. corrosive gases and embrittling gases (see ISO 11114-1).
6.1.5 Some grades of stainless steel can be susceptible to environmental stress corrosion cracking.
Special precautions shall be taken in such cases, such as appropriate coating.
6.1.6 Some grades of stainless steel can be susceptible to phase transformation at low temperatures
resulting in a brittle alloy. Special precautions shall be taken in such cases, i.e. not using the cylinder
below the minimum acceptable temperature.
6.2 Controls on chemical composition
6.2.1 The following are the four broad categories of stainless steels:
— ferritic;
— martensitic;
— austenitic;
— austenitic/ferritic (duplex).
Recognized steels are listed in ISO 15510. Other grades of stainless steel can also be used provided that
they fulfil all the requirements of this document.
6.2.2 The cylinder manufacturer shall obtain and make available certificates of cast (heat) analyses
of the steels supplied for the construction of gas cylinders.
Should check analyses be required, they shall be carried out either on the specimens taken during the
manufacture from the material in the form as supplied by the steel maker to the cylinder manufacturer,
or from finished cylinders. In any check analysis, the maximum permissible deviation from the limits
specified for the cast analyses shall conform to the values specified in ISO 9329-4.
6.3 Heat treatment
6.3.1 The cylinder manufacturer shall certify the heat treatment process applied to the finished
cylinders.
6.3.2 The finished cylinders made from the ferritic or martensitic steel categories shall be quenched
and tempered, except if they are cold worked (see 6.4).
6.3.3 For the ferritic and martensitic steels, the heat treatment process shall achieve the required
mechanical properties.
6.3.4 The actual
...
NORME ISO
INTERNATIONALE 9809-4
Deuxième édition
2021-11
Bouteilles à gaz — Conception,
construction et essais des bouteilles
à gaz et des tubes rechargeables en
acier sans soudure —
Partie 4:
Bouteilles en acier inoxydable ayant
une valeur de R inférieure à 1 100
m
MPa
Gas cylinders — Design, construction and testing of refillable
seamless steel gas cylinders and tubes —
Part 4: Stainless steel cylinders with an R value of less than 1 100
m
MPa
Numéro de référence
ISO 9809-4:2021(F)
© ISO 2021
---------------------- Page: 1 ----------------------
ISO 9809-4:2021(F)
DOCUMENT PROTÉGÉ PAR COPYRIGHT
© ISO 2021
Tous droits réservés. Sauf prescription différente ou nécessité dans le contexte de sa mise en œuvre, aucune partie de cette
publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique,
y compris la photocopie, ou la diffusion sur l’internet ou sur un intranet, sans autorisation écrite préalable. Une autorisation peut
être demandée à l’ISO à l’adresse ci-après ou au comité membre de l’ISO dans le pays du demandeur.
ISO copyright office
Case postale 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Genève
Tél.: +41 22 749 01 11
E-mail: copyright@iso.org
Web: www.iso.org
Publié en Suisse
ii
© ISO 2021 – Tous droits réservés
---------------------- Page: 2 ----------------------
ISO 9809-4:2021(F)
Sommaire Page
Avant-propos .v
Introduction . vi
1 Domaine d’application . 1
2 Références normatives .1
3 Termes et définitions . 2
4 Symboles . 3
5 Contrôles et essais .4
6 Matériaux . 5
6.1 Exigences générales . 5
6.2 Contrôles de la composition chimique . 5
6.3 Traitement thermique . 6
6.4 Formage à froid ou cryoformage . 6
6.5 Non-respect des exigences relatives aux essais . 6
7 Conception .7
7.1 Exigences générales . 7
7.2 Conception de l’épaisseur de l’enveloppe cylindrique . 7
7.3 Conception des extrémités convexes (ogives et fonds) . 7
7.4 Conception des fonds concaves . 9
7.5 Conception du goulot . 9
7.6 Frettes de pied . 10
7.7 Collerettes . 10
7.8 Plan de conception . 10
8 Construction et exécution .10
8.1 Généralités . 10
8.2 Épaisseur de la paroi . 10
8.3 Imperfections de surface . 11
8.4 Contrôle ultrasons . 11
8.5 Ovalisation . 11
8.6 Diamètre moyen . 11
8.7 Rectitude . 11
8.8 Verticalité et stabilité .12
8.9 Filetage du goulot .12
9 Procédure d’approbation de type .13
9.1 Exigences générales .13
9.2 Essai de prototype. 14
9.2.1 Exigences générales . 14
9.2.2 Essai de cyclage en pression . 14
9.2.3 Vérification du fond . 15
9.2.4 Essai de serrage pour filtrage conique uniquement .15
9.2.5 Calcul de la contrainte de cisaillement pour les filetages parallèles . 16
9.3 Certificat d’approbation de type . 16
9.4 Essais d’approbation de type/de production spécifiques pour les bouteilles
commandées en petites quantités. 16
10 Essais par lot .17
10.1 Exigences générales . 17
10.2 Essai de traction . 19
10.3 Essai de pliage et essai d’aplatissement . 19
10.3.1 Essai de pliage . . 19
10.3.2 Essai d’aplatissement . 20
10.3.3 Essai d’aplatissement sur anneau . 21
iii
© ISO 2021 – Tous droits réservés
---------------------- Page: 3 ----------------------
ISO 9809-4:2021(F)
10.4 Essai de résistance aux chocs . 21
10.5 Essai de rupture hydraulique . 23
10.5.1 Installation d’essai .23
10.5.2 Conditions d’essai . 24
10.5.3 Interprétation des résultats d’essai . 25
10.6 Essai de corrosion intergranulaire . 26
11 Essais/examens sur chaque bouteille .26
11.1 Généralités . 26
11.2 Essai hydraulique . 27
11.2.1 Essai de résistance à la pression . 27
11.2.2 Essai d’expansion volumétrique . 27
11.3 Essai de dureté . 27
11.4 Essai de fuites . 27
11.5 Vérification de la contenance .28
12 Certification .28
13 Marquage .28
Annexe A (normative) Description et évaluation des imperfections de fabrication et
des critères de rejet des bouteilles à gaz en acier sans soudure au moment de
l’inspection finale par le fabricant .29
Annexe B (normative) Contrôle ultrasons .43
Annexe C (informative) Exemple de certificat d’approbation de type.49
Annexe D (informative) Exemple de certification de réception .50
Annexe E (informative) Exemple de calcul de la résistance au cisaillement pour les filetages
parallèles.52
Bibliographie .54
iv
© ISO 2021 – Tous droits réservés
---------------------- Page: 4 ----------------------
ISO 9809-4:2021(F)
Avant-propos
L'ISO (Organisation internationale de normalisation) est une fédération mondiale d'organismes
nationaux de normalisation (comités membres de l'ISO). L'élaboration des Normes internationales est
en général confiée aux comités techniques de l'ISO. Chaque comité membre intéressé par une étude
a le droit de faire partie du comité technique créé à cet effet. Les organisations internationales,
gouvernementales et non gouvernementales, en liaison avec l'ISO participent également aux travaux.
L'ISO collabore étroitement avec la Commission électrotechnique internationale (IEC) en ce qui
concerne la normalisation électrotechnique.
Les procédures utilisées pour élaborer le présent document et celles destinées à sa mise à jour sont
décrites dans les Directives ISO/IEC, Partie 1. Il convient, en particulier, de prendre note des différents
critères d'approbation requis pour les différents types de documents ISO. Le présent document a
été rédigé conformément aux règles de rédaction données dans les Directives ISO/IEC, Partie 2 (voir
www.iso.org/directives).
L'attention est attirée sur le fait que certains des éléments du présent document peuvent faire l'objet de
droits de propriété intellectuelle ou de droits analogues. L'ISO ne saurait être tenue pour responsable
de ne pas avoir identifié de tels droits de propriété et averti de leur existence. Les détails concernant
les références aux droits de propriété intellectuelle ou autres droits analogues identifiés lors de
l'élaboration du document sont indiqués dans l'Introduction et/ou dans la liste des déclarations de
brevets reçues par l'ISO (voir www.iso.org/brevets).
Les appellations commerciales éventuellement mentionnées dans le présent document sont données
pour information, par souci de commodité, à l’intention des utilisateurs et ne sauraient constituer un
engagement.
Pour une explication de la nature volontaire des normes, la signification des termes et expressions
spécifiques de l'ISO liés à l'évaluation de la conformité, ou pour toute information au sujet de l'adhésion
de l'ISO aux principes de l’Organisation mondiale du commerce (OMC) concernant les obstacles
techniques au commerce (OTC), voir www.iso.org/avant-propos.
Le présent document a été élaboré par le comité technique ISO/TC 58, Bouteilles à gaz, sous-comité SC 3,
Construction des bouteilles.
Cette deuxième édition annule et remplace la première édition (ISO 9809-4:2014), qui a fait l’objet d’une
révision technique. Les principales modifications par rapport à l’édition précédente sont les suivantes:
— mise à jour de l’Article 5;
— clarification de la Figure 3;
— clarification de 8.9;
— modification de 9.1, 9.2, 9.2.4 et de l’Annexe A;
— ajout du paragraphe 9.2.5 pour les filetages parallèles;
— ajout du paragraphe 9.4 pour les bouteilles commandées en petites quantités.
Une liste de toutes les parties de la série ISO 9809 se trouve sur le site web de l’ISO.
Il convient que l’utilisateur adresse tout retour d’information ou toute question concernant le présent
document à l’organisme national de normalisation de son pays. Une liste exhaustive desdits organismes
se trouve à l’adresse www.iso.org/fr/members.html.
v
© ISO 2021 – Tous droits réservés
---------------------- Page: 5 ----------------------
ISO 9809-4:2021(F)
Introduction
Le présent document fournit une spécification pour la conception, la fabrication, le contrôle et les essais
d’une bouteille en acier inoxydable sans soudure. L’objectif est de parvenir à un équilibre entre les
aspects liés à la conception et au rendement économique d’une part, et les exigences d’acceptabilité
internationale et d’utilité universelle d’autre part.
L’ISO 9809 (toutes les parties) vise à éliminer les préoccupations concernant le climat, les contrôles
redondants et les restrictions imposées du fait de l’absence de Normes internationales reconnues.
Le présent document a été élaboré de sorte à pouvoir être référencé dans le Règlement type des
[1]
Nations Unies .
vi
© ISO 2021 – Tous droits réservés
---------------------- Page: 6 ----------------------
NORME INTERNATIONALE ISO 9809-4:2021(F)
Bouteilles à gaz — Conception, construction et essais des
bouteilles à gaz et des tubes rechargeables en acier sans
soudure —
Partie 4:
Bouteilles en acier inoxydable ayant une valeur de R
m
inférieure à 1 100 MPa
1 Domaine d’application
Le présent document spécifie les exigences minimales concernant le matériau, la conception, la
construction et la mise en œuvre, les procédés de fabrication, les examens et les essais au moment de la
fabrication des bouteilles à gaz rechargeables en acier sans soudure d’une contenance en eau inférieure
ou égale à 150 l.
Il s’applique aux bouteilles pour les gaz comprimés, liquéfiés et dissous ayant une résistance à la traction
réelle, R , maximale inférieure à 1 100 MPa.
ma
NOTE Si cela est souhaité, les bouteilles d’une contenance en eau comprise entre 150 l et 450 l peuvent être
fabriquées conformément au présent document.
2 Références normatives
Les documents suivants sont cités dans le texte de sorte qu’ils constituent, pour tout ou partie de leur
contenu, des exigences du présent document. Pour les références datées, seule l’édition citée s’applique.
Pour les références non datées, la dernière édition du document de référence s’applique (y compris les
éventuels amendements).
ISO 148-1, Matériaux métalliques — Essai de flexion par choc sur éprouvette Charpy — Partie 1: Méthode
d'essai
ISO 3651-2, Détermination de la résistance à la corrosion intergranulaire des aciers inoxydables — Partie 2:
Aciers ferritiques, austénitiques et austéno-ferritiques (duplex) — Essais de corrosion en milieux contenant
de l'acide sulfurique
ISO 6506-1, Matériaux métalliques — Essai de dureté Brinell — Partie 1: Méthode d'essai
ISO 6508-1, Matériaux métalliques — Essai de dureté Rockwell — Partie 1: Méthode d’essai
ISO 6892-1, Matériaux métalliques — Essai de traction — Partie 1: Méthode d'essai à température ambiante
ISO 9328-1, Produits plats en acier pour service sous pression — Conditions techniques de livraison —
Partie 1: Exigences générales
ISO 9329-4, Tubes sans soudure en acier pour service sous pression — Conditions techniques de livraison —
Partie 4: Aciers inoxydables austénitiques
ISO 9712, Essais non destructifs — Qualification et certification du personnel END
ISO 10286, Bouteilles à gaz — Vocabulaire
ISO 13341, Bouteilles à gaz — Montage des robinets sur les bouteilles à gaz
ISO 13769, Bouteilles à gaz — Marquage
1
© ISO 2021 – Tous droits réservés
---------------------- Page: 7 ----------------------
ISO 9809-4:2021(F)
3 Termes et définitions
Pour les besoins du présent document, les termes et définitions de l'ISO 10286 ainsi que les suivants,
s’appliquent.
L’ISO et l’IEC tiennent à jour des bases de données terminologiques destinées à être utilisées en
normalisation, consultables aux adresses suivantes:
— ISO Online browsing platform: disponible à l’adresse https:// www .iso .org/ obp;
— IEC Electropedia: disponible à l’adresse https:// www .electropedia .org/ .
3.1
lot
quantité pouvant atteindre 200 bouteilles, plus celles nécessaires aux essais destructifs, de même
diamètre nominal, de même épaisseur, de même longueur et de même conception, fabriquées de
manière consécutive sur une même installation à partir de la même coulée d’acier et ayant subi le même
traitement thermique pendant la même durée
3.2
pression de rupture
p
b
pression la plus haute atteinte dans une bouteille lors d’un essai de rupture
3.3
formage à froid
procédé dans lequel la bouteille est soumise à une pression supérieure à la pression d’épreuve (3.11)
de la bouteille afin d’accroître la limite d’élasticité (3.12) de l’acier
3.4
cryoformage
procédé selon lequel la bouteille est soumise à un traitement de déformation contrôlé à basse
température afin d’augmenter sa résistance de façon permanente
3.5
facteur de contrainte théorique
F
rapport de la contrainte équivalente de paroi à la pression d’épreuve, p , (3.11) à la la contrainte minimale
h
d’élasticité garantie, R
eg
3.6
trempe
traitement thermique de durcissement au cours duquel une bouteille qui a été portée à une température
uniforme supérieure à celle du point critique supérieur, Ac , de l’acier, est refroidie rapidement dans un
3
milieu adapté
3.7
rejeter
mettre une bouteille de côté (niveau 2 ou 3) et refuser sa mise en service
3.8
rendre inutilisable
traiter une bouteille de manière à rendre impossible son utilisation
Note 1 à l'article: Des exemples de méthodes acceptables pour rendre les bouteilles inutilisables peuvent
être trouvés dans l’ISO 18119. Le présent document ne couvre pas les actions visant à rendre les bouteilles
inutilisables.
3.9
réparer
ramener l’état d’une bouteille rejetée au niveau 1
2
© ISO 2021 – Tous droits réservés
---------------------- Page: 8 ----------------------
ISO 9809-4:2021(F)
3.10
revenu
traitement thermique d’adoucissement qui suit la trempe (3.6), au cours duquel une bouteille est portée
à une température uniforme inférieure à celle du point critique, Ac , de l’acier
1
3.11
pression d’épreuve
p
h
pression requise appliquée pendant un essai de pression
Note 1 à l'article: La pression d’épreuve est utilisée pour le calcul de l’épaisseur de la paroi de la bouteille.
3.12
limite d’élasticité
valeur correspondant à la limite conventionnelle d’élasticité à 0,2 %, ou, pour les aciers austénitiques
à l’état recuit de mise en solution, à la limite conventionnelle d’élasticité à 1 %
3.13
pression de service
pression établie d’un gaz comprimé à une température de référence uniforme de 15 °C dans une
bouteille à gaz pleine
4 Symboles
A allongement après rupture, exprimé en pourcentage
a épaisseur minimale calculée de l’enveloppe cylindrique, exprimée en millimètres
a′ épaisseur minimale garantie de l’enveloppe cylindrique, exprimée en millimètres
a épaisseur minimale garantie d’un fond concave à la jointure, exprimée en millimètres
1
(voir Figure 2)
a épaisseur minimale garantie au centre d’un fond concave, exprimée en millimètres
2
(voir Figure 2)
b épaisseur minimale garantie au centre d’un fond convexe, exprimée en millimètres
(voir Figure 1)
c écart maximal autorisé du profil de rupture pour les bouteilles trempées et revenues,
1
exprimé en millimètres (voir Figure 11)
c écart maximal autorisé du profil de rupture pour les bouteilles cryoformées ou en recuit de
2
mise en solution ayant une épaisseur de paroi inférieure à 7,5 mm, exprimé en millimètres
(voir Figure 12)
D diamètre nominal extérieur de la bouteille, exprimé en millimètres (voir Figure 1)
D diamètre du mandrin, exprimé en millimètres (voir Figure 6)
f
F facteur de contrainte théorique (variable)
H hauteur extérieure de la partie bombée (ogive ou fond convexe), exprimée en millimètres
(voir Figure 1)
h profondeur extérieure (fond concave), exprimée en millimètres (voir Figure 2)
L longueur initiale entre repères comme définie dans l’ISO 6892-1, exprimée en millimètres
o
(voir Figure 5)
3
© ISO 2021 – Tous droits réservés
---------------------- Page: 9 ----------------------
ISO 9809-4:2021(F)
l longueur totale de la bouteille, exprimée en millimètres (voir Figure 3)
n rapport du diamètre du mandrin utilisé pour l’essai de pliage à l’épaisseur réelle de l’éprouvette,
t
p pression de rupture réelle, exprimée en bars, au-dessus de la pression atmosphérique
b
5
NOTE 1 bar = 10 Pa = 0,1 MPa.
p pression d’épreuve hydraulique, exprimée en bars, au-dessus de la pression atmosphérique
h
p pression à la limite élastique observée pendant l’essai de rupture hydraulique, exprimée en bars,
y
au-dessus de la pression atmosphérique
r rayon de raccordement interne, exprimé en millimètres (voir Figure 1 et Figure 2)
R valeur réelle de la limite d’élasticité déterminée par l’essai de résistance à la traction,
ea
exprimée en mégapascals (voir 10.2)
R valeur minimale garantie de la limite d’élasticité (voir 7.1.1) pour la bouteille finie,
eg
exprimée en mégapascals
R valeur réelle de la résistance à la traction déterminée par l’essai de résistance à la traction,
ma
exprimée en mégapascals (voir 10.2)
R valeur minimale garantie de la résistance à la traction pour la bouteille finie, exprimée
mg
en mégapascals
S section initiale de l’éprouvette de traction conformément à l’ISO 6892-1,
o
exprimée en millimètres carrés
t épaisseur réelle de l’éprouvette, exprimée en millimètres
t épaisseur moyenne de la paroi d’une bouteille dans la zone de l’essai d’aplatissement,
m
exprimée en millimètres
u rapport de la distance entre les bords du couteau ou des plateaux pour l’essai d’aplatissement
à l’épaisseur moyenne de la paroi de la bouteille dans la zone de l’essai
V contenance en eau de la bouteille, en litres
w largeur de l’éprouvette de traction, en millimètres (voir Figure 5)
5 Contrôles et essais
L’évaluation de la conformité du présent document doit prendre en compte la règlementation applicable
dans les pays d’utilisation.
Afin de s’assurer que les bouteilles sont conformes au présent document, elles doivent être soumises
à des contrôles et essais conformément aux Articles 9, 10 et 11.
Les essais et examens visant à démontrer la conformité au présent document doivent être effectués
à l’aide d’instruments étalonnés avant leur mise en service et réalisés selon un programme établi.
4
© ISO 2021 – Tous droits réservés
---------------------- Page: 10 ----------------------
ISO 9809-4:2021(F)
6 Matériaux
6.1 Exigences générales
6.1.1 Les matériaux utilisés pour la fabrication des bouteilles à gaz doivent faire partie de l’une des
catégories suivantes:
a) aciers pour bouteilles reconnus au plan international;
b) aciers pour bouteilles reconnus au plan national;
c) nouvelles catégories d’acier pour bouteilles, résultant de progrès techniques.
Toutes ces catégories doivent respecter les conditions pertinentes énoncées en 6.2 et 6.3.
6.1.2 Le traitement à chaud des aciers inoxydables austénitiques et duplex entraîne un risque
de sensibilisation à la corrosion intergranulaire (par exemple, appauvrissement en chrome au joint
de grains). Un essai de corrosion intergranulaire doit être réalisé pour ces matériaux conformément à
10.6.
6.1.3 Le fabricant de bouteilles doit établir des moyens permettant d’identifier les bouteilles avec les
coulées d’acier à partir desquelles elles ont été fabriq
...
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 9809-4
ISO/TC 58/SC 3
Gas cylinders — Design, construction
Secretariat: BSI
and testing of refillable seamless steel
Voting begins on:
2021-08-18 gas cylinders and tubes —
Voting terminates on:
Part 4:
2021-10-13
Stainless steel cylinders with an R
m
value of less than 1 100 MPa
Bouteilles à gaz — Conception, construction et essais des bouteilles à
gaz et des tubes rechargeables en acier sans soudure —
Partie 4: Bouteilles en acier inoxydable avec une valeur R
m
inférieure à 1 100 MPa
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 9809-4:2021(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
©
NATIONAL REGULATIONS. ISO 2021
---------------------- Page: 1 ----------------------
ISO/FDIS 9809-4:2021(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
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 or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved
---------------------- Page: 2 ----------------------
ISO/FDIS 9809-4:2021(E)
Contents Page
Foreword .v
Introduction .vi
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Symbols .3
5 Inspection and testing .4
6 Materials .4
6.1 General requirements . 4
6.2 Controls on chemical composition . 5
6.3 Heat treatment . 5
6.4 Cold working or cryoforming . 5
6.5 Failure to meet test requirements . 6
7 Design .6
7.1 General requirements . 6
7.2 Design of cylindrical shell thickness . 6
7.3 Design of convex ends (heads and bases). 7
7.4 Design of the concave base ends. 9
7.5 Neck design . 9
7.6 Foot rings .10
7.7 Neck rings .10
7.8 Design drawing .10
8 Construction and workmanship .10
8.1 General .10
8.2 Wall thickness .10
8.3 Surface imperfections .10
8.4 Ultrasonic examination .10
8.5 Out-of-roundness .11
8.6 Mean diameter .11
8.7 Straightness .11
8.8 Verticality and stability .11
8.9 Neck threads .12
9 Type approval procedure .12
9.1 General requirements .12
9.2 Prototype test .13
9.2.1 General requirements .13
9.2.2 Pressure cycling test .14
9.2.3 Base check .14
9.2.4 Torque test for taper thread only .15
9.2.5 Shear stress calculation for parallel threads .15
9.3 Type approval certificate.15
9.4 Specific type approval/production tests for cylinders ordered in small quantities .16
10 Batch tests .16
10.1 General requirements .16
10.2 Tensile test .18
10.3 Bend test and flattening test .19
10.3.1 Bend test .19
10.3.2 Flattening test . . .20
10.3.3 Ring flattening test .20
10.4 Impact test .20
© ISO 2021 – All rights reserved iii
---------------------- Page: 3 ----------------------
ISO/FDIS 9809-4:2021(E)
10.5 Hydraulic burst test .23
10.5.1 Test installation . .23
10.5.2 Test conditions.24
10.5.3 Interpretation of test results .24
10.6 Intergranular corrosion test .25
11 Tests/examinations on every cylinder .25
11.1 General .25
11.2 Hydraulic test .26
11.2.1 Proof pressure test .26
11.2.2 Volumetric expansion test .26
11.3 Hardness test .26
11.4 Leak test .26
11.5 Capacity check .27
12 Certification .27
13 Marking .27
Annex A (normative) Description and evaluation of manufacturing imperfections
and conditions for rejection of seamless steel gas cylinders at the time of final
inspection by the manufacturer .28
Annex B (normative) Ultrasonic examination .43
Annex C (informative) Example of type approval certificate .49
Annex D (informative) Example of acceptance certificate .50
Annex E (informative) Example of shear strength calculation for parallel threads.52
Bibliography .54
iv © ISO 2021 – All rights reserved
---------------------- Page: 4 ----------------------
ISO/FDIS 9809-4:2021(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 Committee ISO/TC 58, Gas cylinders, Subcommittee SC 3,
Cylinder design.
This second edition cancels and replaces the first edition (ISO 9809-4:2014), which has been technically
revised. The main changes compared with the previous edition are as follows:
— update of Clause 5;
— clarification of Figure 3;
— clarification of 8.9;
— modification of 9.1, 9.2, 9.2.4 and Annex A;
— new subclause 9.2.5 for parallel threads;
— new subclause 9.4 for cylinders ordered in small quantities.
A list of all parts in the ISO 9809 series can be found on the ISO website.
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.
© ISO 2021 – All rights reserved v
---------------------- Page: 5 ----------------------
ISO/FDIS 9809-4:2021(E)
Introduction
This document provides a specification for the design, manufacture, inspection and testing of a
seamless stainless steel cylinder. The objective is to balance the design and economic efficiency against
international acceptance and universal utility.
ISO 9809 (all parts) aims to eliminate the concern about climate, duplicate inspections and restrictions
because of the lack of definitive International Standards.
[1]
This document has been written so that it is suitable to be referenced in the UN Model Regulations .
vi © ISO 2021 – All rights reserved
---------------------- Page: 6 ----------------------
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 9809-4:2021(E)
Gas cylinders — Design, construction and testing of
refillable seamless steel gas cylinders and tubes —
Part 4:
Stainless steel cylinders with an R value of less than 1 100
m
MPa
1 Scope
This document specifies the minimum requirements for the materials, design, construction and
workmanship, manufacturing processes, examinations and testing at time of manufacture for refillable,
seamless, stainless steel gas cylinders with water capacities up to and including 150 l.
It is applicable to cylinders for compressed, liquefied and dissolved gases with a maximum actual
tensile strength, R , of less than 1 100 MPa.
ma
NOTE If so desired, cylinders of water capacity between 150 l and 450 l can be manufactured to be in full
conformance to this document.
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 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method
ISO 3651-2, Determination of resistance to intergranular corrosion of stainless steels — Part 2: Ferritic,
austenitic and ferritic-austenitic (duplex) stainless steels — Corrosion test in media containing sulfuric acid
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 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 9328-1, Steel flat products for pressure purposes — Technical delivery conditions — Part 1: General
requirements
ISO 9329-4, Seamless steel tubes for pressure purposes — Technical delivery conditions — Part 4: Austenitic
stainless steels
ISO 9712, Non-destructive testing — Qualification and certification of NDT personnel
ISO 10286, Gas cylinders — Vocabulary
ISO 13341, Gas cylinders — Fitting of valves to gas cylinders
ISO 13769, Gas cylinders — Stamp marking
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 10286 and the following apply.
© ISO 2021 – All rights reserved 1
---------------------- Page: 7 ----------------------
ISO/FDIS 9809-4:2021(E)
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
3.1
batch
quantity of up to 200 cylinders, plus cylinders for destructive testing of the same nominal diameter,
thickness, length and design made successively on the same equipment, from the same cast of steel, and
subjected to the same heat treatment for the same duration of time
3.2
burst pressure
p
b
highest pressure reached in a cylinder during a burst test
3.3
cold working
process in which a cylinder is subjected to a pressure higher than the cylinder test pressure (3.11) to
increase the yield strength (3.13) of the steel
3.4
cryoforming
process where the cylinder is subjected to a controlled low-temperature deformation treatment that
results in a permanent increase in strength
3.5
design stress factor
F
ratio of the equivalent wall stress at test pressure, p , (3.11) to guaranteed minimum yield strength, R
h eg
3.6
quenching
hardening heat treatment in which a cylinder, which has been heated to a uniform temperature above
the upper critical point, Ac , of the steel, is cooled rapidly on a suitable medium
3
3.7
reject
action to set aside a cylinder (Level 2 or Level 3) that is not allowed to go into service
3.8
rendered unserviceable
cylinder that has been treated in such a way as to render it impossible for use
Note 1 to entry: Examples for acceptable methods to render cylinders unserviceable can be found in ISO 18119.
Any actions on cylinders rendered unserviceable are outside the scope of this document.
3.9
repair
action to return a rejected cylinder to a Level 1 condition
3.10
tempering
toughening heat treatment which follows quenching (3.6), in which the cylinder is heated to a uniform
temperature below the critical point, Ac , of the steel
1
2 © ISO 2021 – All rights reserved
---------------------- Page: 8 ----------------------
ISO/FDIS 9809-4:2021(E)
3.11
test pressure
p
h
required pressure applied during a pressure test
Note 1 to entry: Test pressure is used for the cylinder wall thickness calculation.
3.12
yield strength
stress value corresponding to the 0,2 % proof stress or for austenitic steels in the solution-annealed
condition, 1 % proof stress
3.13
working pressure
settled pressure of a compressed gas at a uniform reference temperature of 15 °C in a full gas cylinder
4 Symbols
A percentage elongation after fracture
a calculated minimum thickness, in mm, of the cylindrical shell
a′ guaranteed minimum thickness, in mm, of the cylindrical shell
a guaranteed minimum thickness, in mm, of a concave base at the knuckle (see Figure 2)
1
a guaranteed minimum thickness, in mm, at the centre of a concave base (see Figure 2)
2
b guaranteed minimum thickness, in mm, at the centre of a convex base (see Figure 1)
c maximum permissible deviation, in mm, of burst profile for quenched and tempered cylinders
1
(see Figure 11)
c maximum permissible deviation, in mm, of the burst profile for cryoformed or solution-annealed
2
cylinders with less than 7,5 mm wall thickness (see Figure 12)
D nominal outside diameter of the cylinder, in mm (see Figure 1)
D diameter, in mm, of former (see Figure 6)
f
F design stress factor (variable)
H outside height, in mm, of the domed part (convex head or base end) (see Figure 1)
h outside depth (concave base end), in mm (see Figure 2)
L original gauge length, in mm, as defined in ISO 6892-1 (see Figure 5)
o
l overall length of the cylinder, in mm (see Figure 3)
n ratio of the diameter of the bend test former to the actual thickness of test piece, t
p measured burst pressure, in bar, above atmospheric pressure
b
5
NOTE 1 bar = 10 Pa = 0,1 MPa.
p hydraulic test pressure, in bar, above atmospheric pressure
h
p observed pressure when the cylinder starts yielding during the hydraulic burst test, in bar,
y
above atmospheric pressure
© ISO 2021 – All rights reserved 3
---------------------- Page: 9 ----------------------
ISO/FDIS 9809-4:2021(E)
r inside knuckle radius, in mm (see Figures 1 and 2)
R actual value of the yield strength, in megapascals, as determined by the tensile test (see 10.2)
ea
R minimum guaranteed value of the yield strength (see 7.1.1), in megapascals, for the finished
eg
cylinder
R actual value of the tensile strength, in megapascals, as determined by the tensile test (see 10.2)
ma
R minimum guaranteed value of the tensile strength, in megapascals, for the finished cylinder
mg
S original cross-sectional area of the tensile test piece, in square mm, in accordance with
o
ISO 6892-1
t actual thickness of the test specimen, in mm
t average cylinder wall thickness at the position of testing during the flattening test, in mm
m
u ratio of the distance between the knife edges or platens in the flattening test to the average
cylinder wall thickness at the position of the test
V water capacity of the cylinder, in litres
w width, in mm, of the tensile test piece (see Figure 5)
5 Inspection and testing
Assessment of conformity to this document shall take into account the applicable regulations of the
countries of use.
To ensure that cylinders conform to this document, they shall be subject to inspection and testing in
accordance with Clauses 9, 10 and 11.
Tests and examinations performed to demonstrate compliance with this document shall be conducted
using instruments calibrated before being put into service and thereafter according to an established
programme.
6 Materials
6.1 General requirements
6.1.1 Materials for the manufacture of gas cylinders shall fall within one of the following categories:
a) internationally recognized cylinder steels;
b) nationally recognized cylinder steels;
c) new cylinder steels resulting from technical progress.
For all categories, the relevant conditions specified in 6.2 and 6.3 shall be satisfied.
6.1.2 There is a risk of intergranular corrosion in austenitic and duplex stainless steels resulting from
hot processing which can cause sensitization of the steel (e.g. chromium depletion in the grain boundary).
Intergranular corrosion testing shall be carried out for such materials in accordance with 10.6.
6.1.3 The cylinder manufacturer shall establish the means to identify the cylinders with the cast of
steel from which they are made.
4 © ISO 2021 – All rights reserved
---------------------- Page: 10 ----------------------
ISO/FDIS 9809-4:2021(E)
6.1.4 Grades of steel used for the cylinder manufacture shall be compatible with the intended gas
service, e.g. corrosive gases and embrittling gases (see ISO 11114-1).
6.1.5 Some grades of stainless steel can be susceptible to environmental stress corrosion cracking.
Special precautions shall be taken in such cases, such as appropriate coating.
6.1.6 Some grades of stainless steel can be susceptible to phase transformation at low temperatures
resulting in a brittle alloy. Special precautions shall be taken in such cases, i.e. not using the cylinder
below the minimum acceptable temperature.
6.2 Controls on chemical composition
6.2.1 The following are the four broad categories of stainless steels:
— ferritic;
— martensitic;
— austenitic;
— austenitic/ferritic (duplex).
Recognized steels are listed in ISO 15510. Other grades of stainless steel can also be used provided that
they fulfil all the requirements of this document.
6.2.2 The cylinder manufacturer shall obtain and make available certificates of cast (heat) analyses of
the steels supplied for the construction of gas cylinders.
Should check analyses be required, they shall be carried out either on the specimens taken during the
manufacture from the material in the form as supplied by the steel maker to the cylinder manufacturer,
or from finished cylinders. In any check analysis, the maximum permissible deviation from the limits
specified for the cast analyse
...
Questions, Comments and Discussion
Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.