ISO 18154:2017

Ships and marine technology — Safety valve for cargo tanks of LNG carriers — Design and testing requirements

ISO 18154:2017 specifies the requirements of design, test and inspection methods for diaphragm-type pilot operated safety valves, which are used in cargo tanks of LNG carriers in order to keep the pressure inside the tank below maximum allowable working pressure.

Navires et technologie maritime — Soupape de sûreté pour les réservoirs de cargaison des méthaniers — Exigences de conception et d'essai

General Information

• Status: Published
• Publication Date: 19-Mar-2017
• ICS: 47.020.30 - Piping systems
• Technical Committee: ISO/TC 8/SC 3 - Piping and machinery
• Drafting Committee: ISO/TC 8/SC 3 - Piping and machinery
• Current Stage: 9093 - International Standard confirmed
• Completion Date: 09-Sep-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 18154
First edition
2017-03
Ships and marine technology — Safety
valve for cargo tanks of LNG carriers
— Design and testing requirements
Navires et technologie maritime — Soupape de sûreté pour les
réservoirs de cargaison des méthaniers — Exigences de conception
et d’essai
Reference number
ISO 18154:2017(E)
©
ISO 2017

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ISO 18154:2017(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

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ISO 18154:2017(E)

Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Main valve components . 2
4.1 Body . 2
4.2 Nozzle. 2
4.3 Disk . 2
4.4 Cover . 2
4.5 Diaphragm . 2
5 Design . 3
6 Materials . 4
7 Production testing and inspection . 4
7.1 Purpose . 4
7.2 Impact test . 4
7.3 Non-destructive inspection . 4
7.4 Pressure test . 5
7.4.1 General requirement . 5
7.4.2 Fluid . 5
7.4.3 Duration. 5
7.4.4 Test equipment . 5
7.5 Surface inspection . 5
7.6 Visual inspection . 5
8 Performance test . 6
8.1 Performance test in ambient temperature . 6
8.1.1 Purpose . 6
8.1.2 Number of test times . 6
8.1.3 Fluid . 6
8.1.4 Acceptance criteria . 6
8.2 Leakage test in ambient temperature . 6
8.2.1 Purpose . 6
8.2.2 Fluid . 6
8.2.3 Test pressure . 6
8.2.4 Duration. 6
8.2.5 Acceptance leakage rate . 6
8.2.6 Test equipment . 7
8.3 Performance test in low temperature . 7
8.3.1 Purpose . 7
8.3.2 Number of test times . 7
8.3.3 Fluid . 7
8.3.4 Acceptance criteria . 7
8.4 Preparation for the performance test in low temperature . 7
8.4.1 Start temperature for the test . 7
8.4.2 Safety requirement . 7
8.4.3 Test system . 7
8.5 Leakage test in low temperature . 8
8.5.1 Purpose . 8
8.5.2 Fluid . 8
8.5.3 Test pressure . 8
8.5.4 Duration. 8
8.5.5 Acceptance tolerance . 9
8.5.6 Test equipment . 9
© ISO 2017 – All rights reserved iii

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ISO 18154:2017(E)

9 Vacuum test . 9
9.1 Purpose . 9
9.2 Vacuum condition . 9
9.2.1 Test temperature . 9
9.2.2 Vacuum set test . 9
9.2.3 Number of test times . 9
9.2.4 Fluid . 9
10 Type test . 9
11 Determination of pilot operated safety valve performance . 9
12 Sizing of pilot operated safety valves .10
13 Marking and sealing .10
Bibliography .11
iv © ISO 2017 – All rights reserved

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ISO 18154:2017(E)

Foreword
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