ISO/FDIS 23555-3

Gas pressure safety and control devices for use in gas transmission, distribution and installations for inlet pressures up to and including 10 MPa — Part 3: Safety shut-off devices

ISO 23555-3 specifies safety, constructional, performance, testing and documentation requirements of gas safety shut-off devices (hereafter referred to as `SSD`). ISO 23555-3 is applicable to SSDs with operating pressures greater than 500 kPa (5 bar) up to 10 MPa (100 bar) of nominal connection sizes up to and including DN 400 for use with fuel gases as natural gas, manufactured gas, biomethane or liquefied petroleum gas (LPG) in commercial, industrial installations, including fuel gas infrastructures. ISO 23555-3 is applicable to SSDs for an operating temperature range from –20 °C to +60 °C; ISO 23555-3 is applicable to: - test methods which are intended for product type test, routine tests and batch surveillance tests; - SSDs which use the pipeline gas as a source of control energy unassisted by any external power source; - SSDs integrating on the same body a second SSD, complying with the requirements in this document; - SSDs integrating a regulator complying with ISO 23555-2. - SSDs incorporating a creep (venting) relief device and/or a vent limiter complying with the requirements in this document; ISO 23555-3 does not apply to: - SSDs upstream from/on/in domestic gas-consuming appliances which are installed downstream of domestic gas meters; - SSDs designed to be incorporated into pressure control systems used in service lines (pipework from the main pipework in a gas infrastructure to the point of delivery of the gas) with declared volumetric flow rate ≤ 200 m3/h (n) and declared inlet pressure ≤ 500 kPa (5 bar); - industrial process control valves on/off type (ref. IEC 60534); - SSDs used in aggressive/sour gas environments (gas environments containing water and H2S are considered sour) or severely corrosive conditions. - SSDs in service conditions with renewables (e.g. H2NG with hydrogen more than 10 %) and/or waste gases (e.g. biogas etc.), if additional information is not provided (e. g. contaminant, liquid etc.).

Dispositifs de commande et de sécurité de la pression de gaz destinés à être utilisés dans les installations de transport, de distribution et de stockage de gaz pour des pressions en entrée jusqu'à 10 MPa inclus — Partie 3: Dispositifs d'arrêt de sécurité

General Information

• Status: Not Published
• ICS: 23.060.40 - Pressure regulators
• ICS: 91.140.40 - Gas supply systems
• Technical Committee: ISO/TC 161 - Controls and protective devices for gas and/or oil
• Drafting Committee: ISO/TC 161 - Controls and protective devices for gas and/or oil
• Current Stage: 5020 - FDIS ballot initiated: 2 months. Proof sent to secretariat
• Start Date: 20-Mar-2024
• Completion Date: 20-Mar-2024

Standards Content (Sample)

FINAL DRAFT
International
Standard
ISO/FDIS 23555-3
ISO/TC 161
Gas pressure safety and control
Secretariat: DIN
devices for use in gas transmission,
Voting begins on:
distribution and installations for
2024-03-20
inlet pressures up to and including
Voting terminates on:
10 MPa —
2024-05-15
Part 3:
Safety shut-off devices
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
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
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.
Reference number
ISO/FDIS 23555-3:2024(en) © ISO 2024

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FINAL DRAFT
ISO/FDIS 23555-3:2024(en)
International
Standard
ISO/FDIS 23555-3
ISO/TC 161
Gas pressure safety and control
Secretariat: DIN
devices for use in gas transmission,
Voting begins on:
distribution and installations for
inlet pressures up to and including
Voting terminates on:
10 MPa —
Part 3:
Safety shut-off devices
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
COPYRIGHT PROTECTED DOCUMENT
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
AND TO PROVIDE SUPPOR TING DOCUMENTATION.
© ISO 2024
IN ADDITION TO THEIR EVALUATION AS
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
LOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
or ISO’s member body in the country of the requester.
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland Reference number
ISO/FDIS 23555-3:2024(en) © ISO 2024

© ISO 2024 – All rights reserved
ii

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ISO/FDIS 23555-3:2024(en)
Contents Page
Foreword .vi
Introduction .vii
1 Scope . 1
2 Normative references . 2
3 Terms, definitions and symbols . 2
3.1 Terms and definitions .2
3.1.1 Terms related to safety shut-off devices in general .2
3.1.2 Terms related to components of safety shut-off devices .3
3.1.3 Terms related to variables in the controlling process .7
3.1.4 Terms related to the controlled process and to the set value of the trip pressure .8
3.1.5 Terms related to functional performances .8
3.1.6 Terms related to the design and tests .10
3.2 Symbols, abbreviated terms and units .
...

ISO/TC 161
Date: 2023-05-11
ISO/CD 23555-3:2023(E)
ISO/TC ISO/FDIS 23555-3
ISO/TC 161
Secretariat: DIN
Date: 2024-03-05
Gas pressure safety and control devices for use in gas
transmission, distribution and installations for inlet pressures up
to and including 10 MPa — —
Part 3: Gas safety
Safety shut-off devices
ICS:
Descriptors:

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FDIS stage

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ISO/DISFDIS 23555-3:2022(E2024(en)
© ISO 20232024
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'sISO’s member body in the country of the requester.
ISO Copyright Officecopyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: + 41 22 749 01 11
Email: [e-mail]
E-mail: [e-mail]
Website: www.iso.orgwww.iso.org
Published in Switzerland.
© ISO 2022 – All rights reserved iii
© ISO 2024 – All rights reserved

iii

---------------------- Page: 3 ----------------------
ISO/DISFDIS 23555-3:2022(E2024(en)
Contents Page
Foreword . xii
Introduction . xiii
1 Scope . 1
2 Normative references . 2
3 Terms, definitions and symbols . 2
3.1 Terms and definitions . 2
3.1.1 Terms related to safety shut-off devices in general . 2
3.1.2 Terms related to components of safety shut-off devices . 3
3.1.3 Terms related to variables in the controlling process . 12
3.1.4 Terms related to the controlled process and to the set value of the trip pressure . 12
3.1.5 Terms related to functional performances . 13
3.1.6 Terms related to the design and tests . 15
3.2 Symbols, abbreviated terms and units . 15
4 Classification . 16
4.1 General . 16
4.2 Temperature classes . 16
4.3 Strength types . 16
4.4 Fail conditions . 16
5 Materials . 16
6 Design .
...