SIST EN ISO 21058:2021

SLOVENSKI STANDARD
oSIST prEN ISO 21058:2021
01-julij-2021
Cestna vozila - Priključek za polnjenje dimetilnega etra (DME) (ISO 21058:2019)
Road vehicles - Dimethyl Ether (DME) refuelling connector (ISO 21058:2019)
Straßenfahrzeuge - Dimethylether (DME) Nachfüllstutzen (ISO 21058:2019)
Véhicules routiers - Connecteur de remplissage en Dimethyl Ether (DME) (ISO
21058:2019)
Ta slovenski standard je istoveten z: prEN ISO 21058
ICS:
43.060.40 Sistemi za gorivo Fuel systems
oSIST prEN ISO 21058:2021 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 21058:2021

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oSIST prEN ISO 21058:2021
INTERNATIONAL ISO
STANDARD 21058
First edition
2019-12
Road vehicles — Dimethyl Ether
(DME) refuelling connector
Véhicules routiers — Connecteur de remplissage en Dimethyl Ether
(DME)
Reference number
ISO 21058:2019(E)
©
ISO 2019

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oSIST prEN ISO 21058:2021
ISO 21058:2019(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
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oSIST prEN ISO 21058:2021
ISO 21058:2019(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative References . 1
3 Terms and definitions . 1
4 General construction requirements . 3
5 Nozzles . 4
6 Standard receptacle dimensions . 4
7 Receptacles . 5
8 Instructions . 6
9 Marking . 6
10 Tests . 7
10.1 General requirements . 7
10.2 Impact resistance . 7
10.2.1 Nozzle test . 7
10.2.2 Receptacle test . 7
10.3 Leakage at room temperature . 8
10.4 Abnormal loads . 8
10.4.1 Test in unpressurised condition . 9
10.4.2 Test in pressurised condition . 9
10.5 Mounting hardware torque .10
10.6 Leakage at low and high temperatures .10
10.7 Nozzle freezing .10
10.8 Durability .10
10.8.1 Endurance .10
10.8.2 Corrosion resistance .12
10.8.3 Brass material compatibility .13
10.8.4 Resistance to dry heat .13
10.8.5 Ozone ageing .13
10.8.6 Temperature cycle .14
10.8.7 Compatibility to Dimethyl Ether .14
10.8.8 Electrical continuity .14
10.9 Hydrostatic strength .14
10.10 Oxygen ageing .15
10.11 Non-metallic material immersion .15
10.12 Vibration resistance .16
10.13 Creep .16
10.14 Automotive fluid exposure.16
10.14.1 General.16
10.14.2 Test method .16
10.14.3 Fluids . . .17
10.14.4 Pass criteria .17
Annex A (normative) Critical dimensions of the nozzle .18
Annex B (informative) Manufacturing and production test plan .19
Bibliography .20
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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 22, Road vehicles, Subcommittee SC 41,
Specific aspects for gaseous fuels.
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.
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Introduction
This document was developed to use for the newly produced Dimethyl Ether vehicle fuelling nozzles
and receptacles only. As such, it applies to nozzles and receptacles used in the Dimethyl Ether fuelling
system and not to the system.
A nozzle meeting the requirements of this document will be functionally compatible from a safety
and performance perspective with all listed receptacles of compatible profile and system pressure.
Similarly, a receptacle meeting the requirements of this document will be functionally compatible from
a safety and performance perspective with all listed nozzles of compatible profile and system pressure.
As there may eventually be many different kinds of nozzles and receptacles available from a variety
of manufacturers which, for safety reasons, should all be compatible with each other, this document
specifies one standardized receptacle profile. This standard profile incorporates the design
specifications (mating materials, geometry and tolerances) which may be considered when evaluating
if a submitted nozzle or receptacle meets the requirement of this document.
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oSIST prEN ISO 21058:2021
INTERNATIONAL STANDARD ISO 21058:2019(E)
Road vehicles — Dimethyl Ether (DME) refuelling
connector
1 Scope
This document applies only to Dimethyl Ether refuelling connectors hereinafter referred to as devices,
constructed entirely of new, unused parts and materials. Dimethyl Ether refuelling connectors consist
of the following components, as applicable:
a) Nozzle (mounted on dispenser side).
b) Receptacle (mounted on vehicle).
This document applies to devices which use Dimethyl Ether as fuel, hereinafter referred to in this
document as D15 [see 9.1 c)].
This document applies to devices with standardised mating components.
This document applies to connectors which prevent Dimethyl Ether vehicles from being fuelled by fuel
station dispensers for other gaseous fuels.
This document is applicable to: Dimethyl Ether in accordance with ISO 16861.
NOTE All references to pressures (kPa) throughout this document are considered gauge pressures unless
otherwise specified.
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 188, Rubber, vulcanized or thermoplastic — Accelerated ageing and heat resistance tests
ISO 1431-1, Rubber, vulcanized or thermoplastic — Resistance to ozone cracking — Part 1: Static and
dynamic strain testing
ISO 1817, Rubber, vulcanized or thermoplastic — Determination of the effect of liquids
ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests
ISO 16861, Petroleum products — Fuels (class F) — Specifications of dimethyl ether (DME)
ASTM D4814Standard Specification for Automotive Spark-Ignition Engine Fuel
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/
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3.1
dry air
air with moisture content such that the dew point of the air at the required test pressure is at least
11 °C below the ambient test temperature
3.2
working pressure
maximum pressure that a connector can be expected to withstand in actual service
3.3
Dimethyl Ether
DME
methoxymethane
organic compound with the formula CH OCH , simplified to C H O
3 3 2 6
Note 1 to entry: Dimethyl Ether is liquid below −25 °C.
3.4
Dimethyl Ether refuelling nozzle
device which permits quick connection and disconnection of fuel supply hose to the Dimethyl Ether
receptacle (3.5) in a safe manner
Note 1 to entry: This term is hereafter referred to as nozzle.
3.5
Dimethyl Ether refuelling receptacle
device connected to a vehicle or storage system which receives the Dimethyl Ether nozzle (3.4) and
permits safe transfer of fuel
Note 1 to entry: This term is hereafter referred to as receptacle.
3.6
Dimethyl Ether refuelling connector
joined assembly of Dimethyl Ether nozzle and receptacle
Note 1 to entry: This term is hereafter referred to as connector.
3.7
non-sparking materials
materials that do not contain, by mass, more than 7,5 % in total of magnesium, titanium and zirconium
[SOURCE: IEC EN 60079-0:2011, 8.3]
3.8
service gasket
replaceable gasket ensuring tightness of the connection between the nozzle outlet and the receptacle inlet
3.9
cycle life
number of connections and disconnections between the nozzle (3.4) and the receptacle (3.5) required
for testing purposes
3.10
service life
number of operations of the check valve in the receptacle for testing purposes
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4 General construction requirements
4.1 Nozzles and receptacles shall be designed in accordance with reasonable concepts of safety,
durability and maintainability.
1) Working pressure. All nozzles and receptacles are designed to have a working pressure defined by
the manufacturer and clearly marked on the device [see 9.1 d)].
2) Design life. All nozzles will be tested at 100 000 connect/disconnect cycles and all receptacles at
20 000 connect/disconnect cycles for conformity with this document. The service gasket may be
changed after minimum of 20 000 cycles.
4.2 Nozzles and receptacles shall be well fitted and manufactured in accordance with good engineering
practice. All construction requirements may be met by either the construction specified in this document
or another construction that gives at least equivalent performance.
4.3 Nozzles and receptacles shall be:
— designed to minimise the possibility of incorrect assembly;
— designed to be secure against displacement, distortion, warping or other damage under normal and
anticipated abnormal conditions of handling and use;
3
— designed to release less than 1 cm of liquid DME during disconnection;
— constructed to maintain operational integrity under normal and reasonable conditions of handling
and usage;
— manufactured and produced according to the test plan in Annex B.
4.4 Nozzles and receptacles shall be manufactured of materials suitable and compatible for use with
Dimethyl Ether, in accordance with ISO 16861, at the pressure and the temperature ranges to which it
will be subjected.
4.4.1 The temperature range shall be for:
For the receptacle:
— Moderate operating conditions: −20 °C to +85 °C
— Cold operating conditions: −40 °C to +85 °C
For the nozzle:
— Moderate operating conditions: −20 °C to +65 °C
— Cold operating conditions: −40 °C to +65 °C
For specific regions, the temperature range specified may not be sufficient. In such a case, a wider
temperature range, representative of that specific region, shall be considered.
4.5 Nozzles and receptacles shall be operated either to connect or disconnect without the use of tools
and with one hand operation.
4.6 Jointing components shall provide gas-tight sealing performance.
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5 Nozzles
The design of the nozzle shall ensure that:
a) it is compatible with the receptacle as specified in Clause 6;
b) entrapment of fingers and/or cold burns are not possible;
c) the maximum push-on force during connection is 100 N at any pressure up to 1 500 kPa in the nozzle;
d) the maximum pull-off force during disconnection is 50 N at 1 500 kPa;
e) the force to operate the lever, if any, applied at the centre of the grip area of the lever, is 100 N
maximum at any pressure up to 1 500 kPa in the nozzle;
f) if a latch is provided and in use, it shall be capable of being normally disarmed by the user;
g) provision is made to enable the lever or the whole nozzle to freely rotate over an angle of 360°
around the longitudinal axis of the nozzle or the filling hose;
h) it is not possible to open the valve in the nozzle if the nozzle is not properly locked and sealed on
the receptacle;
i) a locking mechanism is incorporated that locks in the connected position;
j) it is not possible to unlock the nozzle from the receptacle unless the nozzle valve is closed;
k) internal blocking due to freezing does not occur under intended operating conditions;
l) it will withstand a torque of 150 % of the mounting torque specified by the manufacturer
without damage;
m) the external surfaces of the filling nozzle are corrosion resistant or protected against corrosion
and are made of materials (non-sparking materials) that do not cause sparks when dropped on a
surface;
n) changing the service gasket shall not result in any Dimethyl Ether release;
o) the minimum cycle life of the service gasket is 20 000 cycles;
p) the nozzle is provided with a means to securely attach it to the delivery hose;
q) the nozzle shall comply with the performance requirements of Clause 10 to ensure
interchangeability.
6 Standard receptacle dimensions
A receptacle shall comply with the design specifications detailed in Figure 1.
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Dimensions in millimetres
Figure 1 — D15 receptacle
7 Receptacles
7.1 Receptacles shall comply with Clauses 4 and 6 to 10 and shall be evaluated with a test nozzle
meeting the requirements of this document.
The failure of any test conducted with the receptacle and nozzle test samples shall constitute a failure of
the submitted receptacle, unless the manufacturer can prove the problem was caused by the test nozzle.
7.2 The receptacle shall be equipped with an internal check valve to prevent the escape of gas.
Regardless of whether the check valve is opened mechanically or by differential pressure, the flow through
the receptacle, when tested with water, at a differential pressure of 30 kPa, shall be at least 3 l/min.
The check valve shall be dimensioned to be leak-tight for the complete temperature range, also when
the tank pressure is lower than the ambient pressure.
The dead volume between the front sealing surface and the front of the internal check valve shall not
3
exceed 0,1 cm .
7.3 The method for attaching the receptacle to the vehicle fuel system shall not rely on the joint
between the male and female threads for sealing, such as conical threads.
7.4 The interfacing surface of the receptacle shall be constructed of material that does not cause spark
(non-sparking) and ensures electrical continuity (see 10.8.8).
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7.5 The receptacle shall have provisions to be firmly attached to the vehicle and shall comply with
applicable abnormal load tests (see 10.4).
7.6 The receptacle shall be mounted on the vehicle in compliance with Annex A.
7.7 The receptacle shall not be installed in an area that exceeds a temperature of 85 °C.
7.8 Receptacles shall have a cycle life of more than 20 000 cycles and a service life of more than
100 000 cycles.
8 Instructions
Information required for instructions and provisions shall be in an easily understood form.
Special tools required for connection of receptacles to tubing shall be clearly identified in the
instructions.
Manufacturers of receptacles and nozzles shall provide clear and concise printed instruction and
diagrams in a form that can be easily understood and adequate for:
— proper field assembly,
— installation,
— maintenance,
— replacement of components as appropriate,
— for safe operation by all users,
— suitability and use, and
— storage and handling.
9 Marking
Information required for marking and provisions shall be in an easily understood form. Marking should
be embossed, cast, stamped or otherwise formed in the part. This includes markings baked into an
enamelled surface.
9.1 Nozzles and receptacles shall bear the following information:
a) the manufacturer's or dealer's name, trademark or symbol,
b) the model designation,
c) D15,
d) the working pressure,
e) the minimum design temperature,
f) manufacturer code to ensure traceability, and
g) a certification mark (if required).
9.2 A marking to identify this document shall be provided for each system. This marking may be
located on the package or on a notice placed inside the package in which the device is shipped.
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10 Tests
10.1 General requirements
A nozzle and receptacle shall be tested with receptacle and nozzle designs specified in Clauses 4 to 9.
Unless otherwise stated:
a) tests shall be conducted at room temperature (20 ± 5 °C);
b) all pressure or leak tests shall be conducted with dry air or any other suitable gas; and
c) devices shall be conditioned to attain equilibrium conditions.
The tolerances for test temperatures and pressures shall be:
— for low temperatures: (+0 °C / −5 °C);
— for high temperatures: (+5 °C / −0 °C);
— test pressures: ±10 % of the stated value with a maximum of 100 kPa.
10.2 Impact resistance
10.2.1 Nozzle test
A nozzle conditioned for 4 h at −20 °C for moderate operating conditions or −40 °C for cold operating
conditions shall be connected within 2 min to a 5 m length of 19 mm internal diameter refuelling hose at
room temperature, and then dropped 1,3 m onto a concrete floor as shown in Figure 2. The nozzle shall
be dropped ten times at room temperature, then pressurised at the working pressure and subjected to
ten additional drops. Following the above drops, the nozzle shall be capable of normal connection and
disconnection to the receptacle. In addition, the nozzle shall comply with leakage tests specified in 10.3.
Dimensions in metres
Key
1 horizontal concrete floor
2 solid fixing point
3 Hose
4 nozzle
Figure 2 — Impact resistance test arrangement
10.2.2 Receptacle test
The receptacle shall be subjected to an impact test of 10 J. A hardened steel mass of 1 kg shall be dropped
from a height of 1 m so as to deliver the impact velocity 4,4 m/s. This shall be achieved by mounting
the mass in a pendulum. The receptacle shall be installed horizontally on a solid object. The impact of
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the mass shall be on the centre of the protruding part of the receptacle (see Figure A.1). Following the
above impact test, the receptacle shall comply with leakage tests specified in 10.3.
10.3 Leakage at room temperature
Tests shall be conducted at two different pressures: 20 kPa and 1,5 times working pressure.
Pressurised air or nitrogen shall be applied to the coupled (and uncoupled) device. The external body
shall then be checked for bubble leakage using immersion in room temperature water.
Nozzles and receptacles, coupled and uncoupled, shall be either bubble free on the leak test for 2 min
3
or have a leak rate less than 15 cm /h at a room temperature of 20 °C ± 5 °C. The leak rate shall be
determined according to the following method or any other equivalent method.
A graduated cylinder that is calibrated in cubic centimetres, filled with the test liquid, shall be placed
inverted above the component.
At the end of the test period, the liquid displacement in the graduated cylinder is recorded.
The leakage rate is then calculated using Formula (1):
60 273P
 
(1)
VV=
lt
 
t 101,3T 
where
3
V is the leakage rate, cm /h of air or nitrogen;
l
3
V is the liquid displacement during the test in cm ;
t
t is the time of test, minutes;
P is the atmospheric pressure during test in kPa;
T is the ambient temperature during test in K.
10.4 Abnormal loads
The connected nozzle and receptacle shall be subjected to the following abnormal loads for a period of
5 min in service. These tests shall be conducted separately:
a) Pulls a along the nozzle or receptacle longitudinal axis;
b) Moments b applied in
...