SIST EN 1555-4:2021

SLOVENSKI STANDARD
oSIST prEN 1555-4:2019
01-december-2019
Cevni sistemi iz polimernih materialov za oskrbo s plinastimi gorivi - Polietilen
(PE) - 4. del: Ventili
Plastics piping systems for the supply of gaseous fuels - Polyethylene (PE) - Part 4:
Valves
Kunststoff-Rohrleitungssysteme für die Gasversorgung - Polyethylen (PE) - Teil 4:
Armaturen
Systèmes de canalisations en plastique pour la distribution de combus-tibles gazeux -
Polyéthylène (PE) - Partie 4 : Robinets
Ta slovenski standard je istoveten z: prEN 1555-4
ICS:
83.140.30 Polimerne cevi in fitingi za Plastics pipes and fittings for
snovi, ki niso tekočine non fluid use
91.140.40 Sistemi za oskrbo s plinom Gas supply systems
oSIST prEN 1555-4:2019 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 1555-4:2019

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oSIST prEN 1555-4:2019


DRAFT
EUROPEAN STANDARD
prEN 1555-4
NORME EUROPÉENNE

EUROPÄISCHE NORM

October 2019
ICS 23.060.99 Will supersede EN 1555-4:2011
English Version

Plastics piping systems for the supply of gaseous fuels -
Polyethylene (PE) - Part 4: Valves
Systèmes de canalisations en plastique pour la Kunststoff-Rohrleitungssysteme für die Gasversorgung
distribution de combustibles gazeux - Polyéthylène - Polyethylen (PE) - Teil 4: Armaturen
(PE) - Partie 4 : Robinets
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 155.

If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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.

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 supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.


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. prEN 1555-4:2019 E
worldwide for CEN national Members.

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Contents Page
European foreword . 4
Introduction . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions, symbols and abbreviations . 7
4 Material . 9
4.1 PE compound . 9
4.2 Material for non-polyethylene parts . 9
5 General characteristics . 9
5.1 Appearance of the valve . 9
5.2 Colour . 10
5.3 Design . 10
6 Geometrical characteristics . 10
6.1 General . 10
6.2 Measurement of dimensions. 11
6.3 Dimensions of spigot ends for valves . 11
6.4 Dimensions of valves with electrofusion sockets . 11
6.5 Dimensions of the operating device . 11
7 Mechanical characteristics of assembled valves . 11
7.1 General . 11
7.2 Requirements . 11
Table 1 — Mechanical characteristics . 12
Table 2 — Circumferential (hoop) stress at 80 °C and associated minimum test period . 16
Figure 1 — Position of the test piece for the impact loading test . 17
8 Physical characteristics . 17
8.1 Conditioning . 17
8.2 Requirements . 17
Table 3 — Physical characteristics . 18
9 Performance requirements . 18
10 Marking . 18
10.1 General . 18
10.2 Minimum required marking . 18
Table 4 — Minimum required marking . 19
10.3 Additional marking . 19
11 Delivery conditions . 19
Annex A (normative) Determination of the leaktightness of seat(s) and packing . 20
A.1 General . 20
A.2 Test piece . 20
A.3 Procedure . 20
A.3.1 Conditioning . 20
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A.3.2 Internal Leaktightness test (fully closed valve test) . 20
A.3.3 External Leaktightness test (half open valve) . 20
A.4 Test report . 21
Annex B (normative) Test method for leaktightness and ease of operation after tensile loading 22
B.1 Apparatus . 22
B.2 Test piece . 22
B.3 Conditions . 22
B.4 Procedure . 22
B.5 Test report . 23
Bibliography. 24

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European foreword
This document (prEN 1555-4:2019) has been prepared by Technical Committee CEN/TC 155 “Plastics piping
systems and ducting systems”, the secretariat of which is held by NEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 1555-4:2011.
It has been prepared in liaison with Technical Committee CEN/TC 234 “Gas infrastructure”.
System Standards are based on the results of the work undertaken in ISO/TC 138 “Plastics pipes, fittings and
valves for the transport of fluids”, which is a Technical Committee of the International Organization for
Standardization (ISO).
They are supported by separate standards on test methods to which references are made throughout the
System Standard.
The System Standards are consistent with general standards on functional requirements and on recommended
practice for installation.
EN 1555 consists of the following parts:
— EN 1555-1, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 1: General;
— EN 1555-2, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 2: Pipes;
— EN 1555-3, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 3: Fittings;
— EN 1555-4, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 4: Valves (this
standard);
— EN 1555-5, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 5: Fitness for
purpose of the system;
— CEN/TS 1555-7, Plastics piping systems for the supply of gaseous fuels ― Polyethylene (PE) ― Part 7: Guidance
for the assessment of conformity.
NOTE EN 12007-2:2012 [3] prepared by CEN/TC 234 “Gas infrastructure” deals with the recommended practice for
installation of plastics pipes system in accordance with EN 1555 (all parts).
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Introduction
This document, specifies the requirements for a piping system and its components made from polyethylene
(PE) and which is intended to be used for the supply of gaseous fuels.
Requirements and test methods for material and components, other than valves, are specified in
prEN 1555-1:2019, prEN 1555-2:2019 and prEN 1555-3:2019.
Characteristics for fitness for purpose are covered in prEN 1555-5:2019. CEN/TS 1555-7:2019 [2] gives
guidance for assessment of conformity. Recommended practice for installation is given in EN 12007-2:2012 [3]
prepared by CEN/TC 234.
This part of EN 1555 covers the characteristics of valves.
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1 Scope
This document specifies the characteristics of valves made from polyethylene (PE) for piping systems in the
field of the supply of gaseous fuels.
It is applicable to unidirectional and bi-directional valves with spigot end or electrofusion socket intended to
be fused with PE pipes or fittings conforming to EN 1555-2 and EN 1555-3 respectively.
The PE spigot or electrofusion ends for valves made of material other than polyethylene is intended to be in
accordance with EN 1555-3.
It also specifies the test parameters for the test methods referred to in this document.
In conjunction with Parts 1, 2, 3 and 5 of EN 1555, it is applicable to PE valves, their joints and to joints with
components of PE and other materials intended to be used under the following conditions:
2
1
a) a maximum operating pressure, MOP, up to and including 10 bar ;
For the purpose of this document and the references to EN 28233, MOP is considered to be nominal
pressure.
b) an operating temperature of 20 °C as reference temperature;
NOTE 1 For other operating temperatures, derating coefficients can be used, see EN 1555-5.
c) an operating temperature between −20 °C and +40 °C.
EN 1555 (all parts) covers a range of maximum operating pressures and gives requirements concerning colours
and additives.
NOTE 2 It is the responsibility of the purchaser or specifier to make the appropriate selections from these aspects,
taking into account their particular requirements and any relevant national regulations and installation practices or codes.
This document covers valve bodies designed for connection with pipes with a nominal outside diameter
dn ≤ 400 mm.
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.
EN 682, Elastomeric Seals — Materials requirements for seals used in pipes and fittings carrying gas and
hydrocarbon fluids
EN 736-1:2018, Valves — Terminology — Part 1: Definition of types of valves
EN 736-2:2016, Valves — Terminology — Part 2: Definition of components of valves
prEN 1555-1:2019, Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 1: General
prEN 1555-2:2019, Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 2: Pipes
prEN 1555-3:2019, Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 3: Fittings

1
1 bar = 0,1 MPa.
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prEN 1555-5:2019, Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 5: Fitness
for purpose of the system
EN 1680, Plastics piping systems — Valves for polyethylene (PE) piping systems — Test method for leaktightness
under and after bending applied to the operating mechanisms
EN 1704, Plastics piping systems — Thermoplastics valves — Test method for the integrity of a valve after
temperature cycling under bending
EN 1705, Plastics piping systems — Thermoplastics valves — Test method for the integrity of a valve after an
external blow
EN 12100, Plastics piping systems — Polyethylene (PE) valves — Test method for resistance to bending between
supports
EN 12119, Plastics piping systems — Polyethylene (PE) valves — Test method for resistance to thermal cycling
EN 28233, Thermoplastic valves — Torque — Test method (ISO 8233)
EN ISO 1133-1, Plastics — Determination of the melt mass-flow rate (MFR) and the melt volume-flow rate (MVR)
of thermoplastics — Part 1: Standard method (ISO 1133-1)
EN ISO 1167-1, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the
resistance to internal pressure — Part 1: General method (ISO 1167-1)
EN ISO 1167-4, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the
resistance to internal pressure — Part 4: Preparation of assemblies (ISO 1167-4)
EN ISO 3127:2017, Thermoplastics pipes — Determination of resistance to external blows — Round-the-clock
method (ISO 3127:1994)
EN ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions (ISO 3126)
EN ISO 11357-6, Plastics — Differential scanning calorimetry (DSC) — Part 6: Determination of oxidation
induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT) (ISO 11357-6)
EN ISO 17778, Plastics piping systems — Fittings, valves and ancillaries — Determination of gaseous flow
rate/pressure drop relationships (ISO 17778)
3 Terms and definitions, symbols and abbreviations
For the purposes of this document, the terms and definitions, symbols and abbreviations given in
prEN 1555-1:2019, EN 736-1:2018, EN 736-2:2016 and the following apply.
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1 General
3.1.1
external leaktightness
leaktightness of the valve body enveloping the space containing the gas, with respect to the atmosphere
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3.1.2
internal leaktightness
leaktightness between the inlet and the outlet of the valve, with the valve in the closed position
3.1.3
leaktightness test
test for both of the following characteristics:
a) the internal leaktightness of a valve's closing seat when closed and pressurized from either side;
b) the external leaktightness of a valve when half open
3.1.4
initiating torque
torque required to initiate movement of the obturator
3.1.5
running torque
torque required to achieve full opening or closing of the valve at maximum allowable operating pressure
3.1.6
leakage
emission of gas from a valve body, or any component of a valve
3.1.7
valve body
main part of a valve which consists of an operating stop system and contains the obturator, seat(s), stem(s) or
shaft(s) and packing seals and provides the terminal ends for connection to the PE pipe/fittings as applicable
3.1.8
operating device
part of a valve for connection with the operating key which allows the opening and the closing of the valve
3.2 Terms relating to design
3.2.1
full bore valve
valve with a flow section equal to or greater than 80% of the section corresponding to the nominal inside
diameter of the body end port
[SOURCE: EN 736-3:2008]
3.2.2
clearway valve
valve designed to have an unobstructed flow way, which allows for the passage of a theoretical sphere with a
diameter that is not less than the nominal inside diameter of the body end port
[SOURCE: EN 736-3:2008]
3.2.3
reduced bore valve
valve with a flow section equal to or greater than 36% of the section corresponding to the nominal inside
diameter of the body end port and which does not correspond to the full bore valve
[SOURCE: EN 736-3:2008]
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4 Material
4.1 PE compound
The PE compound from which the valve body with spigot or electrofusion socket is made shall conform to
prEN 1555-1:2019. The PE components of the valve shall be made only from virgin material conforming to
prEN 1555-1:2019.
4.2 Material for non-polyethylene parts
4.2.1 General
The materials and the constituent elements used in making the valve (including elastomers, greases and any
metal parts as may be used) shall be as resistant to the external and internal environments as the other
elements of the piping system and shall have a life expectancy at least equal to that of the PE pipes conforming
to prEN 1555-2:2019, with which they are intended to be used, under the following conditions:
a) during storage;
b) under the effect of the gas conveyed therein;
c) with respect to the service environment and operating conditions.
The requirements for the level of material performance of non-polyethylene parts shall be at least as stringent
as that of the PE compound for the piping system.
Reprocessed materials shall not be used for stress bearing polymeric parts.
Other materials used in valves in contact with the PE pipe shall not adversely affect pipe performance or initiate
stress cracking.
4.2.2 Metal parts
All metal parts susceptible to corrosion shall be adequately protected, providing this is necessary for the
durability and function of the system.
When dissimilar metallic materials are used which may be in contact with moisture, steps shall be taken to
avoid the possibility of galvanic corrosion.
4.2.3 Elastomers
Elastomeric seals shall conform to EN 682.
Other sealing materials are permitted if proven suitable for gas service.
4.2.4 Greases and lubricants
Greases or lubricants shall not affect the long term performance of the PE valve or valve body and shall not
exude onto fusion areas.
5 General characteristics
5.1 Appearance of the valve
When viewed without magnification, the internal and external surfaces of valves shall be smooth, clean and free
from scoring, cavities or other surface defects to an extent that would prevent conformity to this document.
No component of the valve shall show any signs of damage, scratches, pitting, bubbles, blisters, inclusions or
cracks to an extent that would prevent conformity of the valves to this document.
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5.2 Colour
The colour of the PE parts of valves shall be either black, yellow or orange.
5.3 Design
5.3.1 General
The design of the valve shall be such that, when assembling the valve onto the pipe or other components, the
electrical coils and/or seals or any other ancillary parts are not displaced.
The valve shall be designed to provide the fluid flow passageway and the body ends.
The characteristic of the fluid flow shall be such that the manufacturer will declare the valve as:
a) full bore;
b) clearway;
c) reduced bore.
NOTE See definitions 3.2.1, 3.2.2 and 3.2.3.
5.3.2 Valve body
PE valves bodies and their PE spigot end or electrofusion socket shall have an MOP of at least that of the pipe
to which they are assembled. PE spigot ends or electrofusion sockets shall comply with the requirements as
reported in prEN 1555-3:2019.
The valve body shall be such that it cannot be dismantled.
An operating stop system shall be provided at the fully open and closed positions.
5.3.3 Operating device
The operating device shall be integral with or connected to the stem in such a way that disconnection is
impossible without special equipment.
The valve shall close by turning the operating device clockwise. For a quarter-turn valve, the condition of the
obturator shall be clearly indicated on the top side of the operating device.
Stops shall be provided at the fully open and closed positions.
5.3.4 Seals
The seals shall be so mounted as to be resistant to normally occurring mechanical loads. Creep and cold flow
effects shall be taken into account. Any mechanism that puts a loading on the seals shall be permanently locked.
Line pressure shall not be used as the sole means of seal activation.
6 Geometrical characteristics
6.1 General
Each valve shall be characterized by its dimensions and associated end connections.
Technical data given by the manufacturer shall include at least the following information:
a) the dimensional characteristics, by working drawings;
b) the assembly instructions.
NOTE In order to prevent stress concentrations, any changes in the wall thickness of the valve body is expected to be
gradual.
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6.2 Measurement of dimensions
Dimensions shall be measured in accordance with EN ISO 3126 at (23 ± 2) °C, after being conditioned for at
least 4 h. The measurement shall not be made less than 24 h after manufacture.
NOTE Indirect measurement at the stage of production is allowed at shorter time periods providing evidence is shown
of correlation.
6.3 Dimensions of spigot ends for valves
The dimensions of spigot ends shall conform to prEN 1555-3:2019, Table 3, up to and including d 400 mm.
n
6.4 Dimensions of valves with electrofusion sockets
The dimensions of electrofusion sockets shall conform to prEN 1555-3:2019, Table 1, up to and including d
n
400 mm.
6.5 Dimensions of the operating device
For a quarter-turn valve, the dimension of the operating devices shall be designed so it can be operated with a
+0,5
0
(50 ) mm square socket, (40 ± 2) mm depth.
NOTE For a multi-turn operated valve, the attention is drawn to the requirements specified in EN ISO 5210 [4].
7 Mechanical characteristics of assembled valves
7.1 General
All tests shall be carried out on valve assembled with pipe pieces from the same SDR conforming to
prEN 1555-2:2019, in accordance with the technical instructions of the manufacturer and taking into account
the extreme conditions of utilization described in prEN 1555-5:2019.
NOTE The properties of an assembled valve depend on the properties of the pipes and the valve and on the conditions
of their installation (i.e. geometry, temperature, type, method of conditioning, assembly and fusion procedures).
The technical file of the manufacturer shall include at least the following information:
a) service conditions (e.g. valve temperature limits);
b) assembly instructions;
c) for valves with electrofusion sockets, the fusion instructions (power requirements or fusion parameters
with limits);
d) Air flow rate value.
7.2 Requirements
7.2.1 General
When tested in accordance with the test methods as specified in Table 1 using the indicated parameters, the
valves shall have mechanical characteristics conforming to the requirements given in Table 1.
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Table 1 — Mechanical characteristics
Test parameters
Characteristic Requirements Test method
Parameter Value
Hydrostatic No failure a Shall conform to EN ISO 1167-1
Conditioning time
strength during the test EN ISO 1167-1 and
b
Number of test pieces
g period of any 3 EN ISO 1167-4
(20 °C, 100 h)
Type of test
test piece Water-in-water

Circumferential (hoop)
10,0 MPa
i
stress : PE 80
12,0 MPa
PE 100
12,0 MPa
PE 100-RC
100 h
Test period
20 °C
Test temperature
Hydrostatic No failure a Shall conform to EN ISO 1167-1
Conditioning time
strength during the test EN ISO 1167-1 and
b
Number of test pieces
g period of any 3 EN ISO 1167-4
(80 °C, 165 h)
Type of test
c Water-in-water

test piece
Circumferential (hoop)

i
stress : PE 80
4,5 MPa
PE 100
5,4 MPa
PE 100-RC
5,4 MPa
Test period
165 h
Test temperature
80 °C
Hydrostatic No failure a Shall conform to EN ISO 1167-1
Conditioning time
strength during the test EN ISO 1167-1 and
b
Number of test pieces
g period of any 3 EN ISO 1167-4
(80 °C, 1 000 h)
Type of test
test piece Water-in-water

Circumferential (hoop)

i
stress : PE 80
4,0 MPa
PE 100
5,0 MPa
PE 100-RC
5,0 MPa
Test period
1 000 h
Test temperature
80 °C
Leaktightness of No leakage Test temperature 23 °C Annex A
seat(s) and during the test Type fluid Air or nitrogen
packing period b 1
Number of test pieces
25 mbar
Test pressure
1 h
Duration of the test
Leaktightness of No leakage Test temperature f Annex
...