Ship and marine technology - Technical requirements for dry-disconnect/connect couplings for bunkering liquefied natural gas (ISO 21593:2019)

This technical standard specifies the design, minimum safety, functional and marking requirements, as well as the interface types and dimensions and testing procedures for dry-disconnect/connect couplings for LNG hose bunkering systems intended for use on LNG bunkering ships, tank trucks and shore-based facilities and other bunkering infrastructures. It is not applicable to hydraulically operated quick connect/disconnect couplers (QCDC) used for hard loading arms, which is covered in ISO 16904. Based on the technology used in industrial manufacturing at the time of development of this document, it is applicable to sizes of couplings ranging from DN 25 to DN 200.

Schiff- und Meerestechnik- Trockene Anschluss- und Trennkupplung(en) für das Bunkern flüssigerdgasbetriebener Schiffe (ISO 21593:2019)

Dieses Dokument legt Anforderungen für Konstruktion, minimale Sicherheit, für Funktion und Kennzeichnung, sowie Schnittstellentypen und Maße und Prüfverfahren für LNG Trockenkupplungen fest, die LNG Schlauchbunkersystemen dienen und für LNG Bunkerschiffe, Tanklastwagen und land-basierte Anlagen und andere Bunkerinfrastrukturen bestimmt sind. Es ist nicht anwendbar auf hydraulisch betätigte Schnellkupplungen (QCDC, en: Quick Connect/Disconnect Coupler), die für feste Verladearme Verwendung finden und in ISO 16904 abgedeckt sind.
Basierend auf der Technologie, die zum Zeitpunkt der Erstellung dieses Dokuments in der industriellen Fertigung verwendet wurde, ist es für Kupplungsgrößen von DN 25 bis DN 200 anwendbar.

Navires et technologie maritime - Exigences techniques relatives au couplage de connexion et de déconnexion à sec pour le soutage de gaz naturel liquéfié (ISO 21593:2019)

Ce document spécifie les exigences de conception, de sécurité minimale, de fonctionnement et de marquage, ainsi que les types et dimensions d'interface et les procédures d'essai applicables au couplage de connexion/déconnexion à sec de GNL utilisé pour un système de soutage de GNL par flexible, destiné à être utilisé sur un navire de soutage de GNL, un camion-citerne, une installation terrestre et les autres infrastructures de soutage. Il ne s'applique pas aux coupleurs de connexion et de déconnexion rapide à commande hydraulique (QCDC) utilisés pour un bras de chargement rigide, lesquels sont couverts par l'ISO 16904.
Compte tenu de la technologie actuelle de production industrielle au moment de l'élaboration de ce document, il est applicable aux tailles de coupleurs comprise entre DN25 et DN200.

Ladijska in pristaniška tehnologija - Tehnične zahteve za suhe spoje za priklop in odklop pri polnjenju plovil na utekočinjeni zemeljski plin (ISO 21593:2019)

Ta tehnični standard določa zahteve glede projektiranja, minimalne varnosti, delovanja in označevanja ter tudi vrste vmesnikov in mere ter preskusne postopke za suhe spoje za priklop in odklop pri cevnih sistemih za polnjenje utekočinjenega zemeljskega plina (LNG), namenjenih za uporabo na plovilih na utekočinjeni zemeljski plin, tovornjakih s cisternami ter priobalnih sistemih in drugih infrastrukturah za polnjenje. Ne uporablja se za hidravlično upravljane hitre spojke (QCDC), ki se uporabljajo za trdne prenosne roke, obravnavane v standardu ISO 16904. Na podlagi tehnologije, uporabljane pri industrijski proizvodnji v času priprave tega dokumenta, se uporablja za vse velikosti spojk od DN 25 do DN 200.

General Information

Status
Published
Public Enquiry End Date
04-Dec-2018
Publication Date
02-Dec-2019
Technical Committee
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
09-Oct-2019
Due Date
14-Dec-2019
Completion Date
03-Dec-2019

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SLOVENSKI STANDARD
SIST EN ISO 21593:2020
01-januar-2020
Ladijska in pristaniška tehnologija - Tehnične zahteve za suhe spoje za priklop in
odklop pri polnjenju plovil na utekočinjeni zemeljski plin (ISO 21593:2019)
Ship and marine technology - Technical requirements for dry-disconnect/connect
couplings for bunkering liquefied natural gas (ISO 21593:2019)
Schiff- und Meerestechnik- Trockene Anschluss- und Trennkupplung(en) für das
Bunkern flüssigerdgasbetriebener Schiffe (ISO 21593:2019)
Navires et technologie maritime - Exigences techniques relatives au couplage de
connexion et de déconnexion à sec pour le soutage de gaz naturel liquéfié (ISO
21593:2019)
Ta slovenski standard je istoveten z: EN ISO 21593:2019
ICS:
47.020.99 Drugi standardi v zvezi z Other standards related to
ladjedelništvom in shipbuilding and marine
konstrukcijami na morju structures
SIST EN ISO 21593:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 21593:2020

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SIST EN ISO 21593:2020


EN ISO 21593
EUROPEAN STANDARD

NORME EUROPÉENNE

September 2019
EUROPÄISCHE NORM
ICS 47.020.99
English Version

Ship and marine technology - Technical requirements for
dry-disconnect/connect couplings for bunkering liquefied
natural gas (ISO 21593:2019)
Navires et technologie maritime - Exigences techniques Schiff- und Meerestechnik- Trockene Anschluss- und
relatives au couplage de connexion et de déconnexion à Trennkupplung(en) für das Bunkern
sec pour le soutage de gaz naturel liquéfié (ISO flüssigerdgasbetriebener Schiffe (ISO 21593:2019)
21593:2019)
This European Standard was approved by CEN on 19 January 2019.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 21593:2019 E
worldwide for CEN national Members.

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SIST EN ISO 21593:2020
EN ISO 21593:2019 (E)
Contents Page
European foreword . 3

2

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SIST EN ISO 21593:2020
EN ISO 21593:2019 (E)
European foreword
This document (EN ISO 21593:2019) has been prepared by Technical Committee ISO/TC 8 "Ships and
marine technology" in collaboration with Technical Committee CEN/TC 282 “Installation and
equipment for LNG” the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by March 2020, and conflicting national standards shall
be withdrawn at the latest by March 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the European Commission and the
European Free Trade Association.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 21593:2019 has been approved by CEN as EN ISO 21593:2019 without any modification.

3

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SIST EN ISO 21593:2020

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SIST EN ISO 21593:2020
INTERNATIONAL ISO
STANDARD 21593
First edition
2019-07
Ships and marine technology —
Technical requirements for dry-
disconnect/connect couplings for
bunkering liquefied natural gas
Navires et technologie maritime — Exigences techniques relatives au
couplage de connexion et de déconnexion à sec pour le soutage de gaz
naturel liquéfié
Reference number
ISO 21593:2019(E)
©
ISO 2019

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2019
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
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General requirements . 3
4.1 General . 3
4.2 Basic design principle . 3
4.3 Design parameters . 4
4.4 Functional requirements . 5
4.5 Internal valve . 5
4.6 Protective cap/plug . 6
4.7 Handle. 6
5 Materials . 6
5.1 General . 6
5.2 Body of coupling . 6
5.3 Bolting . 6
5.4 Spring . 6
5.5 Seals . 6
5.6 Welding . 6
6 Interface types and dimensions . 6
7 Marking . 9
8 Testing . 9
8.1 General . 9
8.2 Ambient test conditions .10
8.3 Cryogenic test conditions .10
8.4 Test arrangement .11
8.5 Shell tightness at ambient temperature .12
8.6 Shell strength at ambient temperature .12
8.7 Internal valve tightness at ambient temperature .12
8.8 Internal valve strength at ambient temperature .13
8.9 Shell tightness at minimum working temperature .13
8.10 Internal valve tightness at minimum working temperature .13
8.11 Operation test at minimum working temperature .14
8.12 Electrical conductivity .14
8.13 Manual force at cold conditions under frost .14
8.14 Bending test .14
8.15 Drop test .15
8.16 Endurance test .15
8.17 High-pressure test .16
Bibliography .17
© ISO 2019 – All rights reserved iii

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SIST EN ISO 21593:2020
ISO 21593:2019(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 8, Ships and marine technology.
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 2019 – All rights reserved

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SIST EN ISO 21593:2020
INTERNATIONAL STANDARD ISO 21593:2019(E)
Ships and marine technology — Technical requirements
for dry-disconnect/connect couplings for bunkering
liquefied natural gas
1 Scope
This document specifies the design, minimum safety, functional and marking requirements, as well as
the interface types and dimensions and testing procedures for dry-disconnect/connect couplings for
LNG hose bunkering systems intended for use on LNG bunkering ships, tank trucks and shore-based
facilities and other bunkering infrastructures. It is not applicable to hydraulically operated quick
connect/disconnect couplers (QCDC) used for hard loading arms, which is covered in ISO 16904.
Based on the technology used in industrial manufacturing at the time of development of this document,
it is applicable to sizes of couplings ranging from DN 25 to DN 200.
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 amendment) applies.
ISO 3834 (all parts), Quality requirements for fusion welding of metallic materials
ISO 5208:2015, Industrial valves — Pressure testing of metallic valves
EN 1092-1, Flanges and their joints
EN 12266-1:2012, Industrial valves — Testing of metallic valves — Part 1: Pressure tests, test procedures
and acceptance criteria — Mandatory requirements
ASME B16.5-2009, Pipe flanges and flanged fittings
ASME B31.3-2018, Process piping
3 Terms and definitions
For the purposes of this document, the following terms and definitions 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
bunkering
operation of transferring LNG fuel to a vessel
[SOURCE: ISO 20519:2017, 3.1, modified — Note 1 to entry has been deleted.]
© ISO 2019 – All rights reserved 1

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

3.2
dry-disconnect
method that reduces LNG or natural gas releases into the atmosphere under normal operation to a
negligible amount consistent with safety, either by equipment design or procedural practice
[SOURCE: ISO 20519:2017, 3.6]
3.3
dry-disconnect/connect coupling
coupling
dry disconnect coupling
dry break coupling
mechanical device, consisting of a nozzle (3.4) and a receptacle (3.5), which permits quick connection
and disconnection of a hose bunkering system of the bunker facility to the manifold of the receiving
vessel, in a safe manner, without employing bolts
3.4
nozzle
half part of the dry-disconnect/connect coupling (3.3) typically mounted on the hose bunkering system
of the bunker facility, which permits a quick connection and disconnection to the receiving vessel in a
safe manner
Note 1 to entry: It includes an internal valve to seal the nozzle/bunkering system when disconnected and is
opened after connection by manual operation.
Note 2 to entry: See 4.2.4.
3.5
receptacle
half part of the dry-disconnect/connect coupling (3.3), which is typically mounted to the manifold flange
of the receiving vessel, which permits a quick connection and disconnection of the hose bunkering
system in a safe manner
Note 1 to entry: It includes an internal valve to seal the receptacle/manifold (3.7) system when disconnected and
is opened after connection by manual operation of the nozzle (3.4).
Note 2 to entry: The receptacle shall always be equipped with a seal, as shown in Figure 3.
Note 3 to entry: See 4.2.4.
3.6
dry gas
gas with moisture content such that the dew point of the gas at the required test pressure is at least
11 °C below the ambient test temperature
3.7
manifold
pipe assembly mounted on board LNG-fuelled vessel to which the flange of the receptacle (3.5) is
connected
3.8
verification testing
series of tests to assure that each coupling (3.3) part (including nozzle (3.4) and receptacle (3.5)) meets
all of its design specifications and requirements and that it fulfils its intended purposes
3.9
production testing
process of measuring the properties or performance of the coupling (3.3) and checking it and obtaining
an indication of well productivity before being delivered from factory to customer
2 © ISO 2019 – All rights reserved

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

4 General requirements
4.1 General
The dry-disconnect/connect coupling shall be functionally compatible with the LNG bunkering system;
the nozzle shall be functionally compatible with the corresponding receptacles, and vice versa.
4.2 Basic design principle
4.2.1 The coupling consists of a nozzle and a receptacle. The nozzle allows a quick connection and
disconnection of the LNG bunkering system to the receptacle.
4.2.2 The poppet faces of the internal valve from the nozzle interacts and pushes the receptacle poppet
toward the open position in order to allow a medium flow.
4.2.3 The nozzle and receptacle shall remain in the final position when the coupling is connected and
is in fully open condition.
4.2.4 The typical structure of the two-part coupling is shown in Figure 1 and Figure 2:
Key
1 internal valve
2 poppet
3 flange
4 manifold of LNG receiving vessel
5 receptacle
6 nozzle
7 hose of LNG bunkering facility
8 handle
Figure 1 — Sketch structure of a dry-disconnect/connect coupling — Disconnected condition
© ISO 2019 – All rights reserved 3

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

Key
1 internal valve
2 poppet
3 flange
4 manifold of LNG receiving vessel
5 receptacle
6 nozzle
7 hose of LNG bunkering facility
8 handle
9 coupling
Figure 2 — Sketch structure of a dry-disconnect/connect coupling — Connected condition
4.2.5 The dry disconnect/connect coupling shall be designed according to a design standard for
pressure-containing equipment. Accepted design codes are:
— ASTM Boiler and Pressure Vessel Code;
— European Pressure Equipment Directive 2014/68/EU;
— EN 12516 Industrial Valves – Shell design strength;
— ISO 16904:2016, 7.2 Design of QCDC; Section 7.3 QCDC system; 9.3.8 QCDC (Testing requirements).
Other design codes can be accepted if they provide the same level of safety with respect to pressure
containment.
The wall thickness of the coupling shall take into account, as a minimum but not limited to, the internal
pressure, the external loads and the moments.
4.2.6 The receptacle shall always be equipped with a seal, as shown in Figure 3.
4.3 Design parameters
The design pressure and temperature of the dry-disconnect/connect coupling shall comply with:
a) Minimum design pressure:
1,6 MPa.
4 © ISO 2019 – All rights reserved

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

b) Design temperature:
−196 °C to + 85 °C.
4.4 Functional requirements
4.4.1 An interlock function shall be included to ensure the coupling is sealed first under connection,
before the internal valves are opened. When disconnecting, the internal valves shall be closed first, before
it is possible to disconnect the coupling. This may be achieved by an internal interlock device (two-step
action) or sequential in one single rotating manoeuvre (single-step action).
4.4.2 The volume between the two internal valves shall be as small as practical and reported by the
manufacturer.
4.4.3 Once connected, the coupling shall remain liquid and gas tight under all operating conditions,
and shall sustain:
1. The external loads applied at the connection between the bunkering system and the ship’s manifold
(dynamic and static as well as ice accretion).
2. The internal loads due to the LNG transfer process, either pressure or thermal loads during
transient and permanent phases.
The bending loads shall comply with the value specified in Table 5.
4.4.4 It shall be possible to disconnect the nozzle from the receptacle under the maximum manifold
loads, including an ice build-up on the device with a thickness of:
3
1. for DN 25 to DN 80: 10 mm solid ice (d = 800 kg/m );
3
2. for DN 100 to DN 200: 25 mm solid ice (d = 800 kg/m ).
4.4.5 The design of the coupling shall allow the coupling to be manually connected and disconnected
unaided and the maximum force to (dis)connect the nozzle from the receptacle shall not exceed 350 N.
Where this force exceeds 350 N, actuation shall be pneumatically or hydraulically assisted.
The nozzle shall be so designed as to be operated without the use of tools (e.g. extension bars) and
excessive force for connecting and disconnecting.
4.4.6 The operation direction to open and close shall be indicated with an indelible mark. Connected
condition shall be made with a positive indication that the mechanism action is fully made.
4.4.7 The design of the nozzle and receptacle shall allow for the removal of liquid and vapour before
disconnection, avoiding vapour and liquid trapped in the dead space during purging operation.
4.4.8 The nozzle shall have an integrated swivel function. It shall allow free rotation, to prevent the
application of torsional loads on the bunkering system.
4.4.9 The coupling shall have suitable fire resistance properties and shall be fire type tested in
accordance with recognized standards (e.g. ISO 10497).
4.4.10 The coupling shall be made of conductive, non-sparking material.
4.5 Internal valve
The backwards force of the receptacle poppet in fully open position shall be maximum of 460 N.
© ISO 2019 – All rights reserved 5

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

4.6 Protective cap/plug
A cap/plug or equivalent design feature shall be provided to prevent dust, moisture, and other foreign
debris from entering the nozzle and receptacle. The cap/plug shall not allow the build-up of pressure
between the receptacle and the cap as well as between the nozzle and the plug.
4.7 Handle
A handle is to be fitted to the nozzle to protect the operator from cold injuries.
5 Materials
5.1 General
The material shall be suitable for the use with LNG and for the test conditions with liquid nitrogen
down to −196 °C. Recommendations are mentioned in ISO 16903:2015, Table 3.
5.2 Body of coupling
5.2.1 The coupling shall be made from forged stainless steel ASTM A182 grade F316 or equivalent, in
the solution heat-treated condition.
5.2.2 The coupling may be manufactured from bar material according to ASTM A479, EN 10272 or
equivalent, in a solution heat-treated condition.
5.3 Bolting
Bolting shall be in accordance with ASME/ANSI B16.5 or EN 1092-1.
5.4 Spring
Any springs used within the receptacle or nozzle shall be suitable for the design pressure and
temperature specified in 4.3, and shall be suitable against fatigue for 10 000 cycles that is the same as
the endurance test of 8.16.
5.5 Seals
Seals shall be suitable for the design pressure and temperature specified in 4.3.
5.6 Welding
Welds to stainless steel grade 316 (L) shall be made using welding procedures qualified by impact testing
at –196 °C in accordance with the requirements of ASME B31.3-2018, 323.2.2 or ISO 3834 (all parts) or
equivalent. Material certificates of these welded fittings shall refer to these WPQs.
6 Interface types and dimensions
6.1 The end termination of the receptacle connecting to the manifold system shall be flanged in
accordance with 6.3.
6.2 The end termination of the nozzle connecting to the LNG hose bunkering system shall be flanged
but may be screwed by NPT or JIC below DN 150 in accordance with ASME 1.20.1 or SAE J514.
6 © ISO 2019 – All rights reserved

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

6.3 The flange shall have a raised face ‘RF’ in accordance with ASME/ANSI B16.5 or EN 1092-1, forged
integral with the body, or attached by qualified full penetration butt-welding or inertia welding, followed
by heat treatment as required by the material specification.
6.4 The receptacle shall comply with the dimensions as shown in Figure 3 and Table 1.
Dimension in millimetres
Figure 3 — Interface type and dimensions of the receptacle
© ISO 2019 – All rights reserved 7

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SIST EN ISO 21593:2020
ISO 21593:2019(E)

8 © ISO 2019 – All rights reserved
Table 1 — Dimensions in millimeters
DN 25 min max DN 50 min max DN 65 min max DN 80 min max DN 100 min max DN 150 min max DN 200 min max
A1 13 −0,1 0 14 −0,1 0 14 −0,1 0 15 −0,1 0 18 −0,1 0 30 −0,1 0 40 −0,1 0
A2 11 −0,1 0 11 −0,1 0 11 −0,1 0 12 −0,1 0 14 −0,1 0 25 −0,1 0 28 −0,1 0
A3 29 0 0,05 43 0 0,05 59 0 0,05 78 0 0,05 87 0 0,05 140 0 0,1 192 0 0,1
A4 48 0 0,05 62 0 0,05 78 0
...

SLOVENSKI STANDARD
oSIST prEN ISO 21593:2018
01-november-2018
[Not translated]
Ship and marine technology - Technical requirements for liquefied natural gas bunkering
dry-disconnect/connect coupling (ISO/DIS 21593:2018)
Schiff- und Meerestechnik- Trockene Anschluss- und Trennkupplung(en) für das
Bunkern flüssigerdgasbetriebener Schiffe (ISO/DIS 21593:2018)
Navires et technologie maritime - Exigences techniques relatives au couplage de
connexion et de déconnexion à sec pour le soutage de gaz naturel liquéfié (ISO/DIS
21593:2018)
Ta slovenski standard je istoveten z: prEN ISO 21593
ICS:
47.020.99 Drugi standardi v zvezi z Other standards related to
ladjedelništvom in shipbuilding and marine
konstrukcijami na morju structures
oSIST prEN ISO 21593:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN ISO 21593:2018

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oSIST prEN ISO 21593:2018
DRAFT INTERNATIONAL STANDARD
ISO/DIS 21593
ISO/TC 8 Secretariat: SAC
Voting begins on: Voting terminates on:
2018-09-25 2018-12-18
Ship and marine technology — Technical requirements for
liquefied natural gas bunkering dry-disconnect/connect
coupling
Titre manque
ICS: 47.020.99
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 21593:2018(E)
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Contents Page
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 General requirements . 3
4.1 General . 3
4.2 Basic design principle .3
4.3 Design parameters .4
4.4 Functional requirements .5
4.5 Internal valve .6
4.6 Protective cap/plug . 6
4.7 Handle. 6
5 Materials . 6
5.1 General . 6
5.2 Body of coupling .6
5.3 Bolting . 6
5.4 Spring . 6
5.5 Seals . 6
5.6 Welding . 6
6 Interface type and dimensions . 6
7 Marking . 9
8 Testing . 9
8.1 General . 9
8.2 Ambient test conditions . 10
8.3 Cryogenic test conditions . 10
8.4 Test arrangement . 11
8.5 Shell tightness at ambient temperature . 12
8.6 Shell strength at ambient temperature . 12
8.7 Internal valve tightness at ambient temperature . 12
8.8 Internal valve strength at ambient temperature . 13
8.9 Shell tightness at minimum working temperature . 13
8.10 Internal valve tightness at minimum working temperature . 13
8.11 Operation test at minimum working temperature . 13
8.12 Electrical conductivity . 14
8.13 Manual force at cold conditions under frost . 14
8.14 Bending test . 14
8.15 Drop test . 14
8.16 Endurance Test . 15
8.17 High Pressure test . 16
Bibliography .17
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oSIST prEN ISO 21593:2018
DRAFT INTERNATIONAL STANDARD ISO/DIS 21593:2018(E)
Ship and marine technology — Technical requirements for
liquefied natural gas bunkering dry-disconnect/connect
coupling
1 Scope
This International Standard specifies the design, minimum safety and functional requirements,
inspection and testing procedures for LNG dry-disconnect/connect coupling served for LNG hose
bunkering system intended for use on LNG bunker ship, tank truck and shore-based facility etc. This
standard is not applicable to hydraulically operated quick connect/disconnect coupler (QCDC) used
for hard loading arm since it has been stipulated in ISO 16904. Based on the current technology of
industrial manufacturing, the size of coupling from DN25 to DN200 is to be considered and contained
within this standard at the development period.
The scope of this standard includes the following five elements.
1) General requirements: basic design principle, design parameters, functional requirements, internal
valve, protective cap, handle;
2) Materials: body of coupling, welding, bolting, spring, seals;
3) Interface type and dimensions: Ends termination of receptacle, dimensions;
4) Marking: manufacturer and international standard information;
5) Testing: test conditions, test arrangement, general requirements, verification testing, production
testing.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendment) applies.
ISO 16904, Petroleum and natural gas industries — Design and testing of LNG marine transfer arms for
conventional onshore terminals
EN 12516, Industrial Valves — Shell Design Strength
ASME B31.3, Process piping
ISO 3834, Quality requirements for fusion welding of metallic materials
ISO 16903, Petroleum and natural gas industries — Characteristics of LNG, influencing the design, and
material selection
ISO 5208, Industrial valves — Pressure testing of metallic valves
EN 12266-1, Industrial valves — Testing of metallic valves — Part 1: Pressure tests, test procedures and
acceptance criteria - Mandatory requirements
ISO 20519, Ships and marine technology — Specification for bunkering of liquefied natural gas fuelled vessels
EN 1092-1, Flanges and their joints
ASME B16.5-2009, Pipe flanges and flanged fittings
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ISO 10497, Testing of valves — Fire type-testing requirements
EN 10222-5, Steel forgings for pressure purposes. Martensitic, austenitic and austenitic-ferritic stainless steels
ASTM A479, Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other
Pressure Vessels
EN 10272, Stainless steel bars for pressure purposes
3 Terms and definitions
For the purpose of this document, the following terms and definitions apply.
3.1
Bunkering
Operation of transferring LNG fuel to a vessel.(SOURCE: ISO 20519:2017, 3.1)
3.2
Dry-disconnect
Method that reduces LNG or natural gas releases into the atmosphere under normal operation to a
negligible amount consistent with safety, either by equipment design or procedural practice.(SOURCE:
ISO 20519:2017, 3.6)
3.3
Dry-disconnect/connect coupling
Mechanical device which permits quick connection and disconnection of a hose bunkering system of
the bunker facility to the manifold of the receiving vessel in a safe manner without employing bolts. The
coupling consists of a nozzle part and a receptacle part.
Note 1 to entry: These couplings are also known as “Dry Disconnect Couplings” or “Dry-break Couplings”.
3.4
Nozzle
Half part of the coupling (see 4.2.4), which is typically mounted on the hose bunkering system of the
bunker facility, which permits quick connection and disconnection to the receiving vessel in a safe
manner.It includes an internal valve to seal the nozzle/bunkering system when disconnected and will
be opened after connection by manual operation.
3.5
Receptacle
Half part of the coupling (see 4.2.4), which is typically mounted to the manifold flange of the receiving
vessel, which permits quick connection and disconnection of the hose bunkering system in a safe
manner.It includes an internal valve to seal the receptacle/manifold system when disconnected and
will be opened after connection by manual operation of the nozzle.
3.6
Dry gas
Gas with moisture content such that the dew point of the gas at the required test pressure is at least
11°C below the ambient test temperature.
3.7
Manifold
Pipe assembly mounted on board LNG-fuelled vessel to which the flange of the receptacle is connected.
3.8
Verification testing
A series of tests to assure that each coupling part (including nozzle and receptacle) meets all of its
design specifications and requirements and that it fulfils its intended purpose.
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3.9
Production testing
A process of measuring the properties or performance of the coupling and check it obtaining an
indication of well productivity before being delivered from factory to customer.
4 General requirements
4.1 General
A dry-disconnect/connect coupling shall be functionally compatible with LNG bunkering system; a
nozzle shall be functionally compatible with corresponding receptacles, vice versa.
4.2 Basic design principle
4.2.1 The coupling consists of a nozzle and a receptacle. The nozzle allows quick connection and
disconnection of the LNG bunkering system to the receptacle.
4.2.2 The poppet faces of internal valve from nozzle interacts and pushes the receptacle poppet toward
the open position so as to allow medium flow.
4.2.3 Nozzle and receptacle shall remain in the final position when the coupling is connected and is in
fully open condition.
4.2.4 The typical structure of the two part coupling is shown below in figure 1 and figure 2:
Key
1 internal valve
2 poppet
3 flange
4 manifold of LNG receiving vessel
5 receptacle
6 nozzle
7 hose of LNG bunkering facility
8 handle
Figure 1 — Sketch structure of dry-disconnect/connect coupling (disconnected condition)
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Key
1 internal valve
2 poppet
3 flange
4 manifold of LNG receiving vessel
5 receptacle
6 nozzle
7 hose of LNG bunkering facility
8 handle
9 coupling
Figure 2 — Sketch structure of dry-disconnect/connect coupling (connected condition)
4.2.5 Dry disconnect/connect coupling shall be designed according to a design standard for pressure
containing equipment. Accepted design codes are:
— ASTM Boiler and Pressure Vessel Code
— European Pressure Equipment Directive 2014/68/EU
— EN 12516 Industrial Valves – Shell design strength
— ISO 16904, Section 7.2 Design of QCDC; Section 7.3 QCDC system; 9.3.8 QCDC (Testing requirements)
Other design codes can be accepted if they provide the same level of safety with respect to pressure
containment.
The wall thickness of coupling shall take into account as a minimum but not limited to: internal
pressure, external loads and moments.
4.2.6 Receptacle shall always be equipped with a seal as shown in Figure 3.
4.3 Design parameters
Design pressure and temperature of dry-disconnect/connect coupling shall comply with:
a) Minimum design pressure
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1.6 MPa
b) Design temperature
-196°C to +85°C
4.4 Functional requirements
4.4.1 An interlock function shall be included to ensure the coupling will be sealed first under
connection, before the internal valves will be opened. When disconnecting, the internal valves shall
be closed first, before it is possible to disconnect the coupling. This may be achieved by an additional
interlock device or by two-step action.
4.4.2 The volume between the two internal valves shall be as small as practical and reported by the
manufacturer.
4.4.3 Once connected the coupling shall remain liquid and gas tight under all operating conditions and
sustain:
1. The external loads applied at the connection between the bunkering system and the ship’s manifold.
(dynamic and static as well as ice accretion)
2. The internal loads due to LNG transfer process, either pressure or thermal loads during transient
and permanent phases.
4.4.4 It shall be possible to disconnect the nozzle from the receptacle under the maximum manifold
loads, including specified an ice build up on the device to the thickness of:
1. DN25 to DN80 : 10 mm solid ice ( d= 800 kg/m3)
2. DN100 to DN200 : 25 mm solid ice ( d= 800 Kg/m3)
4.4.5 The design of coupling shall allow the coupling to be manually connected and disconnected
unaided with the maximum force to (dis)connect the nozzle from the receptacle shall not exceed 350 N.
Where this force exceeds 350 N actuation shall be pneumatically or hydraulically assisted.
Nozzle shall be so designed as to be operated without the use of tools (e.g. extension bars) and excessive
force for connecting and disconnecting.
4.4.6 The operation direction for open and close shall be indicated with indelible mark. Connection
and disconnection shall be made with positive indication that mechanism action is fully made. The status
display shall be clear for the operator in consideration with the formation of icing on the surface.
4.4.7 The design of the nozzle and receptacle shall allow for the removal of liquid and vapour before
disconnection.
4.4.8 The nozzle shall have an integrated swivel function. It shall allow free rotation, to prevent the
application of torsional loads on the bunkering system.
4.4.9 The coupling has suitable fire resistance properties and shall be fire type tested in accor
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