ISO/FDIS 11300-1

FINAL DRAFT
International
Standard
ISO/TC 138/SC 8
Piping systems for rehabilitation
Secretariat: JISC
of underground drains, sewers and
Voting begins on:
water supply networks —
2025-11-05
Part 1:
Voting terminates on:
2025-12-31
Polyethylene (PE) material
Systèmes de canalisations pour la réhabilitation des
branchements, des collecteurs d’assainissement et des réseaux
d’alimentation en eau enterrés —
Partie 1: Matériau polyéthylène (PE)
RECIPIENTS OF THIS DRAFT ARE INVITED TO SUBMIT,
WITH THEIR COMMENTS, NOTIFICATION OF ANY
RELEVANT PATENT RIGHTS OF WHICH THEY ARE AWARE
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TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL
TO BECOME STAN DARDS TO WHICH REFERENCE MAY BE
MADE IN NATIONAL REGULATIONS.
Reference number
FINAL DRAFT
International
Standard
ISO/TC 138/SC 8
Piping systems for rehabilitation
Secretariat: JISC
of underground drains, sewers and
Voting begins on:
water supply networks —
Part 1:
Voting terminates on:
Polyethylene (PE) material
Systèmes de canalisations pour la réhabilitation des
branchements, des collecteurs d’assainissement et des réseaux
d’alimentation en eau enterrés —
Partie 1: Matériau polyéthylène (PE)
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.
© ISO 2025
IN ADDITION TO THEIR EVALUATION AS
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BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/CEN PARALLEL PROCESSING
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
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Published in Switzerland Reference number
ii
Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 3
3.1 General .3
3.2 Terms related to techniques .4
3.3 Terms related to characteristics.4
3.4 Terms related to product stages .6
3.5 Terms related to materials .6
3.6 Terms related to Service conditions .7
3.7 Terms related to joints .8
4 Symbols and abbreviated terms. 9
4.1 Symbols .9
4.2 Abbreviated terms .9
5 Pipes .10
5.1 Materials .10
5.1.1 General .10
5.1.2 Virgin material .10
5.1.3 Reprocessable material and recyclable material .10
5.2 General characteristics .10
5.2.1 Appearance .10
5.2.2 Colour .11
5.3 Material characteristics .11
5.4 Geometric characteristics .11
5.5 Mechanical characteristics .11
5.6 Physical characteristics . 12
5.7 Jointing. 12
5.8 Marking . 12
5.9 Regional requirements for pipes . 13
6 Fittings .13
6.1 Materials . 13
6.2 General characteristics . 13
6.3 Material characteristics . 13
6.4 Geometric characteristics . 13
6.5 Mechanical characteristics . 13
6.6 Physical characteristics . 13
6.7 Jointing. 13
6.8 Marking .14
6.9 Regional requirements for fittings .14
7 Ancillary components . 14
8 Fitness for purpose . 14
8.1 Materials .14
8.2 General characteristics .14
8.3 Geometric characteristics . 15
8.4 Mechanical characteristics . 15
8.5 Sampling .16
8.6 Regional requirements for pipes .16
9 Installation practice .16
9.1 Preparatory work .16
9.2 Storage, handling and transport of pipes and fittings .16

iii
9.3 Equipment .17
9.3.1 General .17
9.3.2 Butt fusion equipment and de-beading equipment .17
9.3.3 Pipe skids/rollers . .17
9.3.4 Winching and rod-pulling equipment . .17
9.3.5 Pipe entry guides .18
9.3.6 Electrofusion equipment .18
9.3.7 Inspection equipment .18
9.3.8 Lifting equipment .18
9.4 Installation .18
9.4.1 General .18
9.4.2 Safety precautions .19
9.4.3 Simulated installations .19
9.5 Process-related inspection and testing . 20
9.6 Pipe end termination . 20
9.7 Reconnection to the existing pipeline system . 20
9.8 Final inspection and testing .21
9.9 Documentation .21
Annex A (normative) Additional requirements applicable for lining with continuous pipes .22
Annex B (normative) Additional requirements applicable for lining with close-fit pipes .24
Annex C (normative) Additional requirements for trenchless replacement techniques — Pipe
bursting, pipe extraction, horizontal directional drilling and impact moling .29
Annex D (normative) Layered pipes .34
Annex E (normative) Factory-folded heat-reverted polyethylene (PE) pipe — Determination of
memory ability .35
Annex F (informative) Pipe design considerations specific to pipe bursting and pipe extraction .37
Annex G (informative) Pipe design considerations specific to HDD.39
Annex H (informative) Summary of required elements to be included in installation manuals . 41
Bibliography .43

iv
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).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
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 138, Plastics pipes, fittings and valves for the
transport of fluids, Subcommittee SC 8, Rehabilitation of pipeline systems, in collaboration with the European
Committee for Standardization (CEN) Technical Committee CEN/TC 155, Plastics piping systems and
ducting systems, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna
Agreement).
This first edition of ISO 11300-1, together with ISO 11300-2, ISO 11300-3, ISO/DIS 11300-4 (in preparation)
and ISO 11301-1, cancels and replaces ISO 11296-1:2018, ISO 11296-2:2018, ISO 11296-3:2018,
ISO 11297-1:2018, ISO 11297-2:2018, ISO 11297-3:2018, ISO 11298-1:2018, ISO 11298-2:2018,
ISO 11298-3:2018, ISO 21225-1:2018 and ISO 21225-2:2018, which have been technically revised.
The main changes are as follows:
— for piping systems made from polyethylene (PE) material, this document replaces the related content,
including requirements, of the documents listed above.
A list of all parts in the ISO 11300 series can be found on the ISO website.
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.

v
Introduction
This document is a part of a series of International Standards concerning piping systems of various materials
used for the rehabilitation of existing pipelines in a specified application area:
— ISO 11300 series: Piping systems for rehabilitation of underground drains, sewers and water supply
networks;
— ISO 11301 series: Piping systems for rehabilitation of underground gas supply networks.
The ISO 11300 series and the ISO 11301 series are subdivided into parts covering a specific material per
pipe system.
The ISO 11300 series is subdivided in four parts:
— Part 1: Polyethylene (PE) material (this document);
— Part 2: Thermoset composite materials;
— Part 3: PVC-U material;
— Part 4: Thermoplastic composite materials.
These documents cover various techniques for renovation and trenchless replacement. Furthermore, they
are distinguished from those for conventionally installed plastics piping systems by the requirement to
verify certain characteristics in the “as-installed” condition, after site processing. This is in addition to
specifying requirements for piping system components “as manufactured”.
A consistent structure of clause headings has been adopted for all parts of the ISO 11300 series and the
ISO 11301 series, in order to facilitate direct comparisons across renovation technique families.
Figure 1 shows the clause structure and the relationship between the ISO 11300 series and the ISO 11301 series.
For complementary information, see ISO 11295.
[3]
For assessment of conformity to the requirements of this document, see ISO/TS 23818-1 .

vi
a
In preparation.
Figure 1 — Clause structure of the ISO 11300 series and the ISO 11301 series
The various techniques for rehabilitation of underground drains, sewers and water supply networks,
within the scope of pipeline rehabilitation techniques generally, are shown schematically in Figure 2. For
definitions of standardized renovation techniques shown in Figure 2, but outside the scope of this document,
see ISO 11295.
vii
a
This document is applicable, for pipe systems made from PE materials.
Figure 2 — Technique families for rehabilitation of underground drains, sewers and water supply
networks using plastics pipes, within the scope of pipeline rehabilitation techniques

viii
FINAL DRAFT International Standard ISO/FDIS 11300-1:2025(en)
Piping systems for rehabilitation of underground drains,
sewers and water supply networks —
Part 1:
Polyethylene (PE) material
1 Scope
This document specifies requirements and test methods for pipes and fittings which are part of piping
systems for the rehabilitation, by means of renovation and trenchless replacement, of underground non-
pressure and pressure drains and sewers and water supply networks, which transport water intended for
human consumption, including raw water pipelines.
It is applicable to polyethylene (PE) pipes, fittings and assemblies, as manufactured and as installed. It is not
applicable to the existing pipeline.
It is applicable to the following technique families for renovation, intended to be used at an operating
temperature of 20 °C as the reference temperature:
— lining with continuous pipes;
— lining with close-fit pipes.
This document is applicable to the following technique families for trenchless replacement, intended to be
used at an operating temperature of 20 °C as the reference temperature:
— pipe bursting and pipe extraction;
— horizontal directional drilling and impact moling.
NOTE For applications operating at constant temperatures greater than 20 °C and up to 40 °C, see ISO 4427-1:2019,
Annex A.
When used with lining with continuous pipes, lining with close-fit pipes and trenchless replacement
technique families, this document is applicable to:
— PE solid wall single layered pipes (nominal outside diameter, d ), including any identification stripes;
n
— PE pipes with co-extruded layers on either or both the outside and inside of the pipe (total outside
diameter, d ), as specified in Annex D, where all layers have the same MRS rating.
n
Furthermore, when used with lining with continuous pipes and trenchless replacement this document is
applicable to:
— PE coated pipes (outside diameter, d ) having a peelable, contiguous, thermoplastics additional layer on
n
the outside of the pipe (“coated pipe”), as specified in Annex D.
This document is applicable to jointing by means of butt fusion and electrofusion and to fabricated and
injection-moulded fittings and mechanical connections of PE.

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 1167-1, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the
resistance to internal pressure — Part 1: General method
ISO 1167-2, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the
resistance to internal pressure — Part 2: Preparation of pipe test pieces
ISO 2505, Thermoplastics pipes — Longitudinal reversion — Test method and parameters
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 4427-1:2019, Plastics piping systems for water supply and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 1: General
ISO 4427-2, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 2: Pipes
ISO 4427-3, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 3: Fittings
ISO 4427-5, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 5: Fitness for purpose of the system
ISO 4633, Rubber seals — Joint rings for water supply, drainage and sewerage pipelines — Specification for
materials
ISO 8772, Plastics piping systems for non-pressure underground drainage and sewerage — Polyethylene (PE)
ISO 9967, Thermoplastics pipes — Determination of creep ratio
ISO 9969, Thermoplastics pipes — Determination of ring stiffness
ISO 11295, Plastics piping systems used for the rehabilitation of pipelines — Classification and overview of
strategic, tactical and operational activities
ISO 12176-1, Plastics pipes and fittings — Equipment for fusion jointing polyethylene systems — Part 1: Butt fusion
ISO 12176-2, Plastics pipes and fittings — Equipment for fusion jointing polyethylene systems — Part 2:
Electrofusion
EN 681-1, Elastomeric seal — Material requirements for pipe joint seals used in water and drainage
applications — Part 1: Vulcanized rubber
EN 681-2, Elastomeric seals — Material requirements for pipe joint seals used in water and drainage applications
— Part 2: Thermoplastic elastomers
EN 681-3, Elastomeric seals — Material requirements for pipe joint seals used in water and drainage applications
— Part 3: Cellular materials of vulcanized rubber
EN 681-4, Elastomeric seals — Material requirements for pipe joint seals used in water and drainage applications
— Part 4: Cast polyurethane sealing elements
EN 12201-1, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 1: General
EN 12201-2, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 2: Pipes

EN 12201-3, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 3: Fittings
EN 12201-5, Plastics piping systems for water supply, and for drainage and sewerage under pressure —
Polyethylene (PE) — Part 5: Fitness for purpose of the system
EN 12666-1, Plastics piping systems for non-pressure underground drainage and sewerage — Polyethylene (PE)
— Part 1: Specifications for pipes, fittings and the system
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11295 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1 General
3.1.1
characteristic
property, dimension or other feature of a material or component
3.1.2
declared value
limiting value of a characteristic (3.1.1) declared in advance by the rehabilitation systemsupplier (3.1.5),
which becomes the requirement for the purposes of assessment of conformity
3.1.3
coated pipe
pipe with a peelable, contiguous thermoplastic additional layer on the outside of the pipe
3.1.4
solid wall single layered pipe
pipe with smooth internal and external surface, extruded from the same compound throughout the wall
3.1.5
rehabilitation system supplier
entity that specifies the field and range of application and brings together the components of a rehabilitation
system to meet the requirements of the product standard at the “M” stage (3.4.1), so that when installed
in accordance with the installation manual they meet the requirements of the product standard at the “I”
stage (3.4.2)
3.1.6
system installer
entity that prepares the host pipe, takes the rehabilitation system at the “M” stage (3.4.1) and installs it so
that it is at the “I” stage (3.4.2)
3.1.7
type testing
testing performed to prove that a material, component, joint or assembly is capable of conforming to the
requirements given in the applicable standard

3.2 Terms related to techniques
3.2.1
close fit
situation of the outside of the installed liner relative to the inside of the existing pipeline, which may either
be an interference fit or include a small annular gap resulting from shrinkage and tolerances only
3.2.2
close-fit pipe
continuous lining pipe of thermoplastic material reshaped or otherwise expanded after insertion to achieve
a close fit (3.2.1) to the existing pipeline
3.3 Terms related to characteristics
3.3.1
nominal size
DN
numerical designation of the size of a component related to the inside or outside diameter
Note 1 to entry: It is a convenient round number approximately equal to the manufacturing dimension in millimetres
(mm). It is not applicable to components designated by thread size.
[SOURCE: ISO 4427-1:2019, 3.1.1, modified — inside diameter has been included in the definition.]
3.3.2
nominal size
DN/OD
numerical designation of the size of a component related to the outside diameter
[SOURCE: ISO 4427-1:2019, 3.1.1]
3.3.3
nominal outside diameter
d
n
specified outside diameter, in millimetres, assigned to a nominal size DN/OD (3.3.2)
Note 1 to entry: For thermoplastics solid-wall components, the value of nominal outside diameter is identical to the
minimum mean outside diameter (3.3.5), d .
em,min
[SOURCE: ISO 4427-1:2019, 3.1.2, modified — Note 1 to entry has been added.]
3.3.4
mean outside diameter
d
em
value of the measurement of the outer circumference of the pipe or spigot end of a fitting in any cross-section
divided by π (= 3,142) and rounded to the next greater 0,1 mm
[SOURCE: ISO 4427-1:2019, 3.1.4]
3.3.5
minimum mean outside diameter
d
em,min
minimum value of the mean outside diameter (3.3.4) as specified for a given nominal size (3.3.1)
[SOURCE: ISO 4427-1:2019, 3.1.5]
3.3.6
wall thickness
e
value of the measurement of the wall thickness at any point around the circumference of a component

3.3.7
mean wall thickness
e
m
arithmetic mean of a number of measurements of the wall thickness (3.3.6), regularly spaced around the
circumference and in the same cross-section of a component, including the measured minimum and the
measured maximum values of the wall thickness in that cross-section
[SOURCE: ISO 4427-1:2019, 3.1.12]
3.3.8
minimum wall thickness at any point
e
min
minimum value of the wall thickness (3.3.6) at any point around the circumference of a component, as
specified
[SOURCE: ISO 4427-1:2019, 3.1.10]
3.3.9
nominal wall thickness
e
n
numerical designation of the wall thickness (3.3.6) of a component, which is a convenient round number,
approximately equal to the manufacturing dimension in millimetres (mm)
Note 1 to entry: For thermoplastics components conforming to the different parts of the ISO 4427 series, the value of
nominal wall thickness, e , is identical to the specified minimum wall thickness at any point (3.3.8), e .
n min
[SOURCE: ISO 4427-1:2019, 3.1.8]
3.3.10
nominal thickness of the coating
e
coating
arithmetic mean of a number of measurements of the coating thickness around the circumference and in the
same cross-section of a component
3.3.11
standard dimension ratio
SDR
numerical designation of a pipe series, which is a convenient round number, approximately equal to the
dimension ratio of the nominal outside diameter (3.3.3), d , and the nominal wall thickness (3.3.9), e
n n
[SOURCE: ISO 4427-1:2019, 3.1.14]
3.3.12
ring stiffness
resistance of a pipe to diametric deflection in response to external loading applied along one longitudinal
diametric plane
Note 1 to entry: This definition applies to both long and short-term values.
3.3.13
minimum bending radius
minimum radius at any point throughout the length of the pipeline, measured to the longitudinal axis of the pipe
Note 1 to entry: This is usually expressed as a multiple of the pipe diameter.
3.3.14
lower confidence limit of the predicted hydrostatic strength
σ
LPL
quantity, with the dimensions of stress, which represents the 97,5 % lower confidence limit of the predicted
hydrostatic strength at a temperature θ and time t
Note 1 to entry: It is expressed in megapascals.

3.3.15
melt mass-flow rate
MFR
value relating to the viscosity of the molten material at a specified temperature and load
Note 1 to entry: It is expressed in grams per 10 min (g/10 min).
[SOURCE: ISO 4427-1:2019, 3.3.5]
3.3.16
minimum required strength
MRS
value of σ at 20 °C and 50 years, rounded down to the next smaller value of the R10 series when σ is
LPL LPL
below 10 MPa, or to the next lower value of the R20 series when σ is 10 MPa or greater
LPL
[1] [2]
Note 1 to entry: the R10 series conform to ISO 3 and the R20 series conforms to ISO 497 .
[SOURCE: ISO 4427-1:2019, 3.3.2]
3.3.17
oxidation induction time
relative measure of a stabilized material’s resistance to oxidative decomposition, determined by the
calorimetric measurement of the time interval to the onset of exothermic oxidation of the material at a
specified temperature in an oxygen or air atmosphere, under atmospheric pressure
3.4 Terms related to product stages
3.4.1
“M” stage
stage as manufactured, before any subsequent site processing of components associated with the particular
renovation technique
Note 1 to entry: For pipes and fittings at the “M” stage, see Clauses 5 and 6, respectively.
3.4.2
“I” stage
stage as installed, i.e. in final configuration after any site processing of components associated with the
particular renovation technique
Note 1 to entry: For pipes and fittings at the “I” stage, see Clause 8.
3.5 Terms related to materials
3.5.1
virgin material
material in a form such as granules, powder or liquid, which has not been subjected to use or processing
other than that required for its manufacture and to which no reprocessable or recyclable material (3.5.4) has
been added
3.5.2
own reprocessable material
material prepared from clean, rejected and unused pipes, fittings, or valves, including trimmings from the
production of pipes, fittings or valves, that is reprocessed in a manufacturer’s plant after having previously
been processed by the same manufacture in the production of a component by, for example, injection
moulding or extrusion
[SOURCE: ISO 4427-1:2019, 3.2.2]

3.5.3
external reprocessable material
material from unused products or trimmings which will be reprocessed and which were originally processed
by another manufacturer
Note 1 to entry: If a manufacturer has a production of products other than pipes and fittings, reprocessable material
from that production is considered as external reprocessable material when used for pipes or fittings production.
3.5.4
recyclable material
material prepared from used products which have been cleaned and crushed or ground
3.5.5
compound
homogeneous extruded mixture of base polymer (PE) and additives, i.e. anti-oxidants, pigments, carbon
black, UV-stabilisers, at a dosage level necessary for the processing and use of components conforming to
the requirements of this document
[SOURCE: ISO 4427-1:2019, 3.2.3]
3.5.6
crazing
microstructural phenomenon associated with the short-term application of tensile bending strain exceeding
the material-related critical yield strain
3.5.7
drilling mud
fluid created by mixing water and additives to facilitate drilling and transport of drill cuttings from the drill
bit to the surface
3.6 Terms related to Service conditions
3.6.1
nominal pressure
PN
numerical designation used for reference purposes related to the mechanical characteristics of the
component of a piping system
Note 1 to entry: For thermoplastics piping systems conveying water, it corresponds to the allowable operating
5 2
pressure(PFA) (3.6.3) in bar (1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .), which can be sustained with water at 20 °C
with a design basis of 50 years, and based on the minimum design coefficient (3.6.2):
20×()MRS
PN=
C×−()SDR 1
Note 2 to entry: Research on long term performance prediction of PE water distribution systems shows a possible
service life of at least 100 years, see ISO 4427-1:2019, Reference [4] and Reference [5].
[SOURCE: ISO 4427-1:2019, 3.4.1]
3.6.2
design coefficient
C
coefficient with a value greater than 1 which takes into consideration service conditions as well as properties
of the components of a piping system other than those represented in the lower confidence limit
[SOURCE: ISO 4427-1:2019, 3.3.3]

3.6.3
allowable operating pressure
PFA
maximum hydrostatic pressure that a component is capable of withstanding continuously in service
5 2
Note 1 to entry: It is expressed in bar (1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .)
[SOURCE: ISO 11295:2025, 3.3.2]
3.6.4
surge
rapid fluctuations of pressure, either positive or negative, caused by flow alterations over short periods of
time e.g. due to the switching on or off of pumps or the opening or closing of valves
3.6.5
allowable maximum operating pressure
PMA
maximum internal hydrostatic pressure occurring from time to time, including surge (3.6.4), that a
component is capable of withstanding in service
5 2
Note 1 to entry: It is expressed in bar (1 bar = 0,1 MPa = 10 Pa; 1 MPa = 1 N/mm .)
3.6.6
surge factor
F
surge
value of the ratio PMA/PFA, which is generally a function of pipe material and rate of pressure rise
Note 1 to entry: The value assigned for design can also vary depending upon the anticipated frequency of the surge
conditions.
3.7 Terms related to joints
3.7.1
butt fusion joint
joint made by heating the planed ends of matching surfaces by holding them against a flat heating plate
until the PE material reaches fusion temperature, quickly removing the heating plate and pushing the two
softened ends against one another
[SOURCE: ISO 4427-1:2019, 3.5.2]
3.7.2
electrofusion joint
joint between a PE socket or saddle electrofusion fitting and a pipe or fitting with spigot ends, made by
heating the electrofusion fittings by the Joule effect of the heating element incorporated at their jointing
surfaces, causing the material adjacent to them to melt and pipe and fitting surfaces to fuse
[SOURCE: ISO 4427-1:2019, 3.5.1]
3.7.3
fusion compatibility
ability of two similar or dissimilar PE materials to be fused together to form a joint which conforms to the
performance requirements of this document
3.7.4
mechanical joint
joint made by assembling a PE pipe to another PE pipe, or any other element using a fitting that generally
includes a compression part, to provide for pressure integrity, leaktightness and resistance to end loads
[SOURCE: ISO 4427-1:2019, 3.5.3]

3.7.5
integral joint
joint at the pipe end, either by means of a socket at one pipe end (single-socket pipe) or matching joint parts
integrated in the pipe wall at either end of the pipe (rubber ring joints or screwed joints).
4 Symbols and abbreviated terms
4.1 Symbols
C design coefficient
d outside diameter
e
d mean outside diameter
em
d minimum mean outside diameter
em,min
d original circular outside diameter of the pipe (before processing for insertion)
manuf
d nominal outside diameter
n
e wall thickness
e mean wall thickness
m
e maximum mean wall thickness
m, max
e minimum wall thickness at any point
min
e nominal wall thickness
n
e nominal thickness of the coating
coating
F value of the ratio PMA/PFA
surge
I second moment of area of the profiled plastics strip
w
l length of the sample for short-term tensile force resistance test of the locked seam
s
S ring stiffness of the pipe
T temperature at which stress rupture data have been determined
t time to occurrence of a leak in
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