ISO/FDIS 23826

Gas cylinders -- Ball valves -- Specification and testing

Bouteilles à gaz -- Robinets à boisseau sphérique -- Spécifications et essais

General Information

• Status: Published
• ICS: 23.020.35 - Gas cylinders
• Technical Committee: ISO/TC 58/SC 2 - Cylinder fittings
• Drafting Committee: ISO/TC 58/SC 2/WG 6 - Gas cylinder valves - Specifications and testing
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 26-Jul-2021
• Completion Date: 26-Jul-2021

Standards Content (sample)

FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 23826
ISO/TC 58/SC 2
Gas cylinders — Ball valves —
Secretariat: AFNOR
Specification and testing
Voting begins on:
2021­07­26
Bouteilles à gaz — Robinets à boisseau sphérique — Spécifications et
essais
Voting terminates on:
2021­09­20
ISO/CEN PARALLEL PROCESSING
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 23826:2021(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
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ISO/FDIS 23826:2021(E)
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© ISO 2021

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ii © ISO 2021 – All rights reserved
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ISO/FDIS 23826:2021(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Valve description .................................................................................................................................................................................................. 4

5 Valve design requirements ........................................................................................................................................................................ 7

5.1 General ........................................................................................................................................................................................................... 7

5.2 Materials ....................................................................................................................................................................................................... 7

5.3 Valve connections ................................................................................................................................................................................. 8

5.4 Mechanical strength ........................................................................................................................................................................... 8

5.4.1 Resistance to hydraulic burst pressure ........................................................................................................ 8

5.4.2 Resistance to mechanical impact ....................................................................................................................... 9

5.5 Valve operating mechanism ......................................................................................................................................................... 9

5.6 Valve operating device ...................................................................................................................................................................10

5.7 Leakage .......................................................................................................................................................................................................10

5.8 Securing arrangements .................................................................................................................................................................10

5.9 Manufacturing tests and examinations ...........................................................................................................................11

6 Type testing.............................................................................................................................................................................................................11

6.1 General ........................................................................................................................................................................................................11

6.2 Documentation ....................................................................................................................................................................................13

6.3 Test samples ...........................................................................................................................................................................................13

6.4 Test report ................................................................................................................................................................................................14

6.5 Test temperatures .............................................................................................................................................................................14

6.6 Test pressures .......................................................................................................................................................................................14

6.6.1 Valve burst test pressure .......................................................................................................................................14

6.6.2 Valve test pressure ......................................................................................................................................................14

6.7 Test gases ..................................................................................................................................................................................................14

6.7.1 Gas quality ..........................................................................................................................................................................14

6.7.2 Leak tightness tests ....................................................................................................................................................15

6.7.3 Endurance tests .............................................................................................................................................................15

6.8 Test schedule .........................................................................................................................................................................................15

6.9 Hydraulic burst pressure test ..................................................................................................................................................16

6.10 Flame impingement test ..............................................................................................................................................................16

6.11 Excessive torque test ......................................................................................................................................................................16

6.12 Leak tightness test ............................................................................................................................................................................17

6.12.1 General...................................................................................................................................................................................17

6.12.2 Internal leak tightness test .................. .................................................................................................................17

6.12.3 External leak tightness test..................................................................................................................................18

6.13 Endurance test .....................................................................................................................................................................................19

6.14 Visual examination ...........................................................................................................................................................................19

7 Marking .......................................................................................................................................................................................................................19

8 Operating instructions ................................................................................................................................................................................20

Annex A (normative) Endurance test machine .......................................................................................................................................21

Bibliography .............................................................................................................................................................................................................................23

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ISO/FDIS 23826:2021(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 non­governmental, 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 2,

Cylinder fittings, in collaboration with the European Committee for Standardization (CEN) Technical

Committee CEN/TC 23, Transportable gas cylinders, in accordance with the Agreement on technical

cooperation between ISO and CEN (Vienna Agreement).

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.
iv © ISO 2021 – All rights reserved
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ISO/FDIS 23826:2021(E)
Introduction

This document covers the function of a ball valve as a closure (defined by the UN Model Regulations).

It is possible that additional features of ball valves (e.g. pressure regulators, residual pressure devices,

non-return devices, pressure relief devices) are covered by other standards or regulations.

Ball valves conforming to this document can be expected to perform satisfactorily under normal

service conditions.
This document pays particular attention to:

a) safety (mechanical strength, impact strength, endurance, leak tightness, resistance to acetylene

decomposition);
b) suitability of materials;
c) testing;
d) marking.
[29]

This document has been written so that it is suitable to be referenced in the UN Model Regulations .

In this document the unit bar is used, due to its universal use in the field of technical gases. It should,

however, be noted that bar is not an SI unit, and that the corresponding SI unit for pressure is Pa

5 5 2
(1 bar = 10 Pa = 10 N/m ).

Pressure values given in this document are given as gauge pressure (pressure exceeding atmospheric

pressure) unless noted otherwise.

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.
Any tolerances given in this document include measurement uncertainties.
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FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 23826:2021(E)
Gas cylinders — Ball valves — Specification and testing
1 Scope

This document specifies design, type testing, marking, manufacturing tests and examinations

requirements for ball valves used as:
a) closures of refillable transportable gas cylinders, pressure drums and tubes;
b) main valves for cylinder bundles;

a) c) valves for cargo transport units [e.g. trailers, battery vehicles, multi-element gas containers

(MEGCs)];
which convey compressed gases, liquefied gases and dissolved gases.

NOTE 1 In this document, the term “valve” is used with the meaning of “ball valve”.

This document does not apply to ball valves for:
— oxidizing gases as defined in ISO 10156;
— toxic gases (i.e. gases listed in ISO 10298 having an LC value ≤ 5 000 ppm );
— acetylene for single gas cylinders, pressure drums and tubes.

NOTE 2 The reason for the exclusion of oxidizing gases is that the use of ball valves as closures of high-

pressure cylinders for oxidizing gases is known to lead to specific ignition hazards that cannot reasonably be

mitigated through the ball valve design or type testing. Safety hazards concern both the ball valve itself and any

downstream equipment.

NOTE 3 The reason for the exclusion of acetylene for single gas cylinders, pressure drums and tubes is that the

risk of an acetylene decomposition cannot reasonably be mitigated through the ball valve design or type testing.

This document does not apply to ball valves for liquefied petroleum gas (LPG), cryogenic equipment,

portable fire extinguishers and cylinders for breathing apparatus.
NOTE 4 Requirements for valves for cryogenic vessels are specified in ISO 21011.

NOTE 5 Certain specific requirements for quick-release valves for fixed fire-fighting systems in addition to

those that are given in this document are specified in ISO 16003.
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 148­1, Metallic materials — Charpy pendulum impact test — Part 1: Test method

ISO 10286, Gas cylinders — Terminology

ISO 10524­3, Pressure regulators for use with medical gases — Part 3: Pressure regulators integrated with

cylinder valves (VIPRs)
1) ppm = parts per million.
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ISO/FDIS 23826:2021(E)

ISO 11114­1, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 1:

Metallic materials

ISO 11114­2, Gas cylinders — Compatibility of cylinder and valve materials with gas contents — Part 2:

Non-metallic materials

ISO 14246, Gas cylinders — Cylinder valves — Manufacturing tests and examinations

ISO 15615:— , Gas welding equipment — Acetylene manifold systems for welding, cutting and allied

processes — Safety requirements in high-pressure devices

ISO 22435, Gas cylinders — Cylinder valves with integrated pressure regulators — Specification and type

testing
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 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
ball valve

valve which uses the rotation of a ball with a through-passage to allow or shut-off flow through it

Note 1 to entry: Ball valves can have multiple ports.
3.2
main valve

valve which is fitted to the manifold of a bundle, battery vehicle, battery wagon or multi-element gas

container isolating it from the main connection(s)
[SOURCE: ISO 10286:— , 3.1.5.4]
3.3
valve operating mechanism

mechanism which rotates the ball and which includes the external sealing systems and

can include the internal sealing systems
3.4
valve operating device
component which actuates the valve operating mechanism (3.3)
EXAMPLE Handle/lever, handwheel/knob, key or actuator.
[SOURCE: ISO 10297:2014, 3.3, modified — The example has been changed.]
3.5
stop mechanism
system which limits the position of the valve operating mechanism (3.3)

EXAMPLE Stop pin and stop plate, mechanical stop in valve body and counterpart in handle/lever.

2) Under preparation. Stage at the time of publication: ISO/DIS 15615:2020.
3) Under preparation. Stage at the time of publication: ISO/FDIS 10286:2021.
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ISO/FDIS 23826:2021(E)
3.6
external leak tightness

leak tightness to atmosphere (leakage in and/or leakage out) when the valve is open

[SOURCE: ISO 10297:2014, 3.4, modified — Note 1 to entry has been deleted.]
3.7
internal leak tightness

leak tightness across the seat (leakage in and/or leakage out) when the valve is closed

[SOURCE: ISO 10297:2014, 3.5, modified — Note 1 to entry has been deleted.]
3.8
valve working pressure

settled pressure of a compressed gas at a uniform reference temperature of 15 °C in a full pressure

receptacle for which the valve is intended

Note 1 to entry: This definition does not apply to liquefied gases (e.g. carbon dioxide), or dissolved gases (e.g.

acetylene).

[SOURCE: ISO 10297:2014, 3.6, modified — “pressure receptacle” has replaced “gas cylinder or cylinder

bundle” and Note 2 to entry has been deleted.]
3.9
valve burst test pressure
vbt
minimum pressure applied to a valve during hydraulic burst pressure test
[SOURCE: ISO 10297:2014, 3.7, modified — Note 1 to entry has been deleted.]
3.10
valve test pressure
minimum pressure applied to a valve during testing
[SOURCE: ISO 10297:2014, 3.8, modified — Note 1 to entry has been deleted.]
3.11
lowest operating pressure

lowest settled pressure of the gas(es) for which the ball valve (3.1) is designed

3.12
endurance torque
torque used during the endurance test
Note 1 to entry: The endurance torque is expressed in Nm.

[SOURCE: ISO 10297:2014, 3.11, modified — “torque used” has replaced “closing torque applied”.]

3.13
over torque

torque applied to the valve operating device (3.4) in opening and closing direction which the valve

operating mechanism (3.3) and/or stop mechanism (3.5) can tolerate and remain operable

Note 1 to entry: The over torque is expressed in Nm.

[SOURCE: ISO 10297:2014, 3.12, modified — “torque” has replaced “opening or closing torque (whichever

is the lower value)”, “in opening and closing direction” has replaced “to determine the level of torque”

and “and/or stop mechanism” has been added.]
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ISO/FDIS 23826:2021(E)
3.14
failure torque

opening or closing torque (whichever is the lower value) applied to the valve operating device (3.4) at

which mechanical failure occurs
Note 1 to entry: The failure torque is expressed in Nm.

[SOURCE: ISO 10297:2014, 3.13, modified — “at which mechanical failure occurs” has replaced “to

obtain mechanical failure of the valve operating mechanism and/or valve operating device”.]

3.15
valve inlet connection
connection on the valve which connects the valve to the pressure receptacle

[SOURCE: ISO 10297:2014, 3.16, modified — “pressure receptacle” has replaced “cylinder(s)”.]

3.16
valve outlet connection
connection on the valve used to discharge the pressure receptacle
Note 1 to entry: For most valves, this connection is also used for filling.

[SOURCE: ISO 10297:2014, 3.17, modified — “pressure receptacle” has replaced “cylinder(s)”.]

3.17
valve filling connection
connection on the valve used to fill the pressure receptacle

Note 1 to entry: The valve filling connection can be different from the valve outlet connection (3.16).

[SOURCE: ISO 10297:2014, 3.18, modified — “pressure receptacle” has replaced “cylinder(s)”.]

4 Valve description
4.1 A ball valve (see Figure 1) typically comprises:
a) valve body;
b) valve operating mechanism;
c) valve operating device;
d) stop mechanism;
e) means to ensure internal leak tightness;
f) means to ensure external leak tightness;
g) valve outlet connection(s);
h) valve inlet connection.
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ISO/FDIS 23826:2021(E)
Key
1 stop pin 6 stem sealing
2 valve body 7 seat
3 valve connection (inlet/outlet) 8 ball
4 handle/lever 9 stop plate
5 stem
NOTE Stop plate and handle/lever can be combined in one component.
Figure 1 — Example of a ball valve design
4.2 Ball valves can also include:
a) pressure­relief device;

NOTE 1 The relevant transport regulation can require or forbid pressure relief devices for some gases,

gas mixtures or gas groups. Additional requirements for pressure-relief devices can exist in international/

regional regulations/standards.
b) dip tube;
c) connection plug/cap;
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ISO/FDIS 23826:2021(E)
d) excess flow device;
e) non-return valve on the valve filling connection;
f) residual pressure device with or without non­return function;
NOTE 2 Requirements for residual pressure devices are given in ISO 15996.
g) pressure regulating device;

NOTE 3 Requirements for pressure regulating devices are given in ISO 22435 for industrial applications

and in ISO 10524­3 for medical applications.
h) separate valve filling connection;
i) flow restricting orifice;
j) filter(s).
Not all of these components have test requirements detailed in this document.
4.3 There are typically two ball valve types:
a) floating ball type (see Figure 2);
b) trunnion type (see Figure 3).
The valve designs shown in Figures 2 and 3 are given as typical examples only.
Figure 2 — Floating ball type design
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ISO/FDIS 23826:2021(E)
Figure 3 — Trunnion type design
5 Valve design requirements
5.1 General

Valves shall operate within specification and be leak tight over a range of service temperatures, from at

least −20 °C to +65 °C in indoor and outdoor environments.

When fitted, closed valves shall be internally leak tight during transport and storage (see test 6 in

Table 3) for temperatures down to −40 °C.

Additional testing at higher or lower service temperatures is contingent on specific agreements

between the manufacturer and the purchaser.

Ball valves used in liquefied gas service shall incorporate a cavity relief system (e.g. a vent through the

ball) to prevent trapping of the gas within the ball cavity in the closed condition.

For ball valves with multiple ports, the requirements according to 5.3 and 5.7 (internal leakage only)

shall be fulfilled for each port.

For ball valves where anti-static and fire safe behaviour is of importance, examples of respective

requirements are given in ISO 10497 and in EN 12266-2:2012, Annex B.
5.2 Materials

Metallic and non-metallic materials in contact with the gas shall be chemically and physically compatible

with the gas, in accordance with ISO 11114­1 and ISO 11114­2 under all intended operating conditions.

The compatibility of the lubricant(s) and glue(s), if used in gas wetted areas, shall also be considered.

For valves used for dissolved gases, the compatibility of the materials in contact with the solvent shall

also be considered.

For valves used with gas mixtures, the compatibility of the gas wetted materials with each component

of the gas mixture shall be considered.
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ISO/FDIS 23826:2021(E)

When using plated or coated components in gas wetted areas, the material compatibility of both

the plating/coating material and the substrate material shall be taken into account. In addition,

consideration should be given to avoid separation of the surface coating or particle generation.

The material used for the valve body shall be either:

a) a material not showing a ductile to brittle transition (examples of such materials are copper alloys,

austenitic stainless steels, aluminium alloys and nickel alloys); or

b) a ferritic material (e.g. carbon steel) having an impact value greater than 27 J at −40 °C when

submitted to the Charpy pendulum impact test as specified in ISO 148-1.
5.3 Valve connections
Valve inlet and outlet connections shall conform to:
— an International Standard; or
— regional or national standards; or

— proprietary designs that have been qualified to an acceptable industry standard.

NOTE 1 Valve inlet connection standards are, for example, ISO 11363-1, ISO 15245-1, ISO 228-1, ISO 6162-1,

ISO 6162­2, ISO 11926­1 and ANSI/ASME B1.20.1.

NOTE 2 Valve outlet connection standards are, for example, ISO 5145, ISO 10692-1, ISO 228–1, ISO 6162-1,

ISO 6162­2, ISO 11926­1 and ANSI/ASME B1.20.1. A partial compilation of regional and national standards is

given in ISO/TR 7470.

NOTE 3 Qualification procedures for proprietary valve inlet connection designs are, for example, given in

ISO 10692­2.

NOTE 4 Qualification procedures for proprietary valve outlet connection designs are, for example, given in

CGA V­1.

If the valve filling connection is separate to the valve outlet connection and not equipped with a closure

device (non­return valve or isolating valve), it shall be provided with a pressure­tight device (e.g. a plug

or cap which can be operated or removed only by the use of a special proprietary tool provided by

the manufacturer). Where applicable, such a pressure­tight device shall be designed to vent gas before

becoming disengaged.

The valve filling connection closure device, if fitted, shall conform to the relevant endurance and

subsequent leakage requirements of ISO 22435 for industrial applications or ISO 10524-3 for medical

applications.
5.4 Mechanical strength
5.4.1 Resistance to hydraulic burst pressure

Valves shall withstand valve burst test pressure p (see 6.6.1) without permanent visible deformation

vbt
or burst (rupture).
The hydraulic burst pressure test is given in 6.9.
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ISO/FDIS 23826:2021(E)
5.4.2 Resistance to mechanical impact

This document does not include a test to validate that the valve is inherently able to withstand damage

from impact without release of the contents.

NOTE Applicable transport regulations normally specify a variety of acceptable means to maintain the

integrity of the pressure receptacle. For example, main valves used in cylinder bundles in accordance with

ISO 10961 are protected by the frame.
5.5 Valve operating mechanism

5.5.1 It shall be possible to open and close the valve at pressures up to valve test pressure p (see

6.6.2) without using any additional equipment not recommended by the manufacturer. This shall be

verified during t
...