ISO/DIS 15494.2:2026(en)

ISO/TC 138/SC 03

Secretariat: UNI

Date: 2026-01-28

Plastics piping systems for industrial applications — Polybutene (PB), polyethylene (PE), polyethylene of raised temperature resistance (PE-RT), crosslinked polyethylene (PE-X), polypropylene (PP) — Metric series for specifications for components and the system

Systèmes de canalisations en matiéres plastique pour les applications industrielles — Polybutène (PB), Polyéthylène (PE), polyéthylène de meilleure résistance à la température (PE-RT), polyéthylène réticulé (PE-X), polypropylène (PP) — Séries métriques pour les spécifications pour les composants et le système

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Contents Page

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 document 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 3, Plastics pipes and fittings for industrial applications, 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 third edition cancels and replaces the second edition (ISO 15494:2015), which has been technically revised. It also incorporates the Amendment ISO 15494:2015/Amd. 1:2020.

The main changes are as follows:

— in the text, PE 63 has been deleted with the reference graphs and PE–100 RC has been added;

— in Annex E, the impact resistance of pipes and test parameters for round the clock method has been added.

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.

Introduction

This document specifies the characteristics and requirements for a piping system and its components made from polybutene (PB), polyethylene (PE), polyethylene of raised temperature resistance (PE-RT), crosslinked polyethylene (PE-X), or polypropylene (PP), as applicable, intended to be used for industrial applications above ground or below ground (including buried) by authorities, design engineers, certification bodies, inspection bodies, testing laboratories, manufacturers, and users.

This document is intended for piping components designed for use with other piping components that comply with relevant dimensional and performance criteria, specified in other standards, which are consistent with the requirements for joint dimensions and other applicable provisions of this document.

At the date of publication of this document, published International Standards for piping systems of other plastics used for industrial applications are ISO 15493^[1] and ISO 10931^[2].

Plastics piping systems for industrial applications — Polybutene (PB), polyethylene (PE), polyethylene of raised temperature resistance (PE-RT), crosslinked polyethylene (PE-X), polypropylene (PP) — Metric series for specifications for components and the system

This document specifies the characteristics and requirements for components such as pipes, fittings, and valves made from one of the following materials intended to be used for thermoplastics piping systems under internal pressure from the media or vacuum conditions in the field of industrial applications above and below ground (including buried):

— polybutene (PB);

— polyethylene (PE);

— polyethylene of raised temperature resistance (PE-RT);

— crosslinked polyethylene (PE-X);

— polypropylene (PP).

NOTE 1 Requirements for industrial valves are given in this document and in other standards (see clause 2)

This document is applicable to either PB, PE, PE-RT, PE-X, or PP pipes, fittings, valves, and their joints and to joints with components of other plastics and non-plastic materials, depending on their suitability, intended to be used for the conveyance of liquid and gaseous media as well as solid matter in suspension for industrial applications.

Some examples (but not limited to) of industrial piping applications:

— chemicals;

— industrial sewers;

— power engineering (e.g. cooling and general purpose water);

— mining;

— electroplating and pickling;

— semiconductor;

— agriculture;

— fire fighting;

— water treatment;

— geothermal;

— compressed air;

— carbon dioxide (wet or dry capture, transportation, utilisation, and storage).

NOTE 2 Where relevant, national regulations (e.g. water treatment) are applicable, other application areas are permitted if the requirements of this document and/or applicable national requirements are fulfilled. National regulations in respect of fire behaviour and explosion risk are applicable.

Characteristics and requirements for pipes, fittings, and valves that are applicable for all materials (PB, PE, PE-RT, PE-X, or PP) are covered by the relevant clauses of this document. Characteristics and requirements which are dependent on the material are given in the relevant annex for each material (see Table 1).

Table 1 — Material-specific annexes

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 7‑1, Pipe threads where pressure-tight joints are made on the threads — Part 1: Dimensions, tolerances and designation

ISO 179‑1, Plastics — Determination of Charpy impact properties — Part 1: Non-instrumented impact test

ISO 261, ISO general purpose metric screw threads — General plan

ISO 1133‑1, Plastics — Determination of the melt mass-flow rate (MFR) and melt volume-flow rate (MVR) of thermoplastics — Part 1: Standard method

ISO 1167‑1:2006, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the resistance to internal pressure — Part 1: General method

ISO 1167‑2:2006, 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 1167‑3:2007, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the resistance to internal pressure — Part 3: Preparation of components

ISO 1167‑4:2007, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the resistance to internal pressure — Part 4: Preparation of assemblies

ISO 1183‑1, Plastics — Methods for determining the density of non-cellular plastics — Part 1: Immersion method, liquid pycnometer method and titration method

ISO 1183‑2, Plastics — Methods for determining the density of non-cellular plastics — Part 2: Density gradient column method

ISO 17885, Plastics piping systems — Mechanical fittings for pressure piping systems — Specifications

ISO 2505, Thermoplastics pipes — Longitudinal reversion — Test method and parameters

ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions

ISO 3127, Thermoplastics pipes — Determination of resistance to external blows — Round-the-clock method

ISO 3501, Plastics piping systems — Mechanical joints between fittings and pressure pipes — Test method for resistance to pull-out under constant longitudinal force

ISO 4065, Thermoplastics pipes — Universal wall thickness table

ISO 4427‑1:2019, Plastics piping systems for water supply and for drainage and sewerage under pressure — Polyethylene (PE) — Part 1: General

ISO 4427‑3:2019, Plastics piping systems for water supply, and for drainage and sewerage under pressure — Polyethylene (PE) — Part 3: Fittings

ISO 4437‑1, Plastics piping systems for the supply of gaseous fuels — Polyethylene (PE) — Part 1: General

ISO 6964, Polyolefin pipes and fittings — Determination of carbon black content by calcination and pyrolysis — Test method

ISO 9080, Plastics piping and ducting systems — Determination of the long-term hydrostatic strength of thermoplastics materials in pipe form by extrapolation

ISO 9854‑1, Thermoplastics pipes for the transport of fluids — Determination of Charpy impact properties — Part 1: General test method

ISO 9854‑2, Thermoplastics pipes for the transport of fluids — Determination of Charpy impact properties — Part 2: Test conditions for pipes of various materials

ISO 10147, Pipes and fittings made of crosslinked polyethylene (PE-X) — Estimation of the degree of crosslinking by determination of the gel content

ISO 11414, Plastics pipes and fittings — Preparation of polyethylene (PE) pipe/pipe or pipe/fitting test piece assemblies by butt fusion

ISO 11922‑1:2018, Thermoplastics pipes for the conveyance of fluids — Dimensions and tolerances — Part 1: Metric series

ISO 11357‑6, Plastics — Differential scanning calorimetry (DSC) — Part 6: Determination of oxidation induction time (isothermal OIT) and oxidation induction temperature (dynamic OIT)

ISO 12162, Thermoplastics materials for pipes and fittings for pressure applications — Classification, designation and design coefficient

ISO 13477, Thermoplastics pipes for the conveyance of fluids — Determination of resistance to rapid crack propagation (RCP) — Small-scale steady-state test (S4 test)

ISO 13479:2022, Polyolefin pipes for the conveyance of fluids — Determination of resistance to crack propagation — Test method for slow crack growth on notched pipes

ISO 13953, Polyethylene (PE) pipes and fittings — Determination of the tensile strength and failure mode of test pieces from a butt-fused joint

ISO 14531‑1, Plastics pipes and fittings — Crosslinked polyethylene (PE-X) pipe systems for the conveyance of gaseous fuels — Metric series — Specifications — Part 1: Pipes

ISO 15512, Plastics — Determination of water content

ISO 16135, Industrial valves — Ball valves of thermoplastics materials

ISO 16136, Industrial valves — Butterfly valves of thermoplastics materials

ISO 16137, Industrial valves — Check valves of thermoplastics materials

ISO 16138, Industrial valves — Diaphragm valves of thermoplastics materials

ISO 16139, Industrial valves — Gate valves of thermoplastics materials

ISO 16770, Plastics — Determination of environmental stress cracking (ESC) of polyethylene — Full-notch creep test (FNCT)

ISO 16871, Plastics piping and ducting systems — Plastics pipes and fittings — Method for exposure to direct (natural) weathering

ISO 18488, Polyethylene (PE) materials for piping systems — Determination of strain hardening modulus in relation to slow crack growth — Test method

ISO 18489:2015, Polyethylene (PE) materials for piping systems — Determination of resistance to slow crack growth under cyclic loading — Cracked Round Bar test method

ISO 18553, Method for the assessment of the degree of pigment or carbon black dispersion in polyolefin pipes, fittings and compounds

ISO 21787, Industrial valves — Globe valves of thermoplastics materials

EN 12099, Plastics piping systems — Polyethylene piping materials and components — Determination of volatile content

For the purposes of this document, the following terms and definitions 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/

3.1.1

nominal outside diameter

d_n

specified outside diameter assigned to a nominal size DN/OD

Note 1 to entry: The nominal inside diameter of a socket is equal to the nominal outside diameter of the corresponding pipe.

Note 2 to entry: It is expressed in millimetres.

3.1.2

outside diameter at any point

d_e

value of the measurement of the outside diameter through its cross-section at any point of the pipe, rounded to the next greater 0,1 mm

Note 1 to entry: The symbol d_e corresponds to d_ey given in other International Standards such as ISO 11922‑1.

3.1.3

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), rounded to the next greater 0,1 mm

3.1.4

mean inside diameter of a socket

arithmetical mean of two measured inside diameters perpendicular to each other

3.1.5

nominal size of flange

DN

numerical designation of the size of a flange for reference purposes and related to the manufacturing dimension in millimetres

3.1.6

out-of-roundness

ovality

difference between the maximum and the minimum outside diameter in the same cross-section of a pipe or spigot

3.1.7

nominal wall thickness

e_n

numerical designation of the wall thickness 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 annexes of ISO 15494, the value of the nominal wall thickness, e_n, is identical to the specified minimum wall thickness at any point, e_min.

3.1.8

wall thickness at any point

e

wall thickness at any point around the circumference of a component rounded to the next greater 0,1 mm

Note 1 to entry: The symbols e corresponds to ey, given in other International Standards such as ISO 11922‑1.

3.1.9

pipe series

S

dimensionless number for pipe designation conforming to ISO 4065

Note 1 to entry: The relationship between the pipe series, S, and the standard dimension ratio, SDR, is given by the following formula, as specified in ISO 4065:

Note 2 to entry: Flanges are designated on the basis of PN.

3.1.10

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, d_n, and the nominal wall thickness, e_n

3.1.11

bend

fitting curved in shape which the relative bending radius is ≥1 x d_n

Note 1 to entry: Bend fittings are manufactured in different ways e.g. injection moulded, prefabricated or swept bends etc.

3.2.1

compound

homogenous extruded mixture of base polymer and additives, i.e. anti-oxidants, pigments, carbon black, UV-stabilizers and others, at a dosage level necessary for the processing and use of components conforming to the requirements of this document

3.2.2

virgin material

material in a form such as granules or powder that has not been subjected to use or processing other than that required for its manufacture, and to which no reworked or recyclable materials have been added

3.2.3

reworked material

plastics materials from rejected unused products or trimmings that have been manufactured and retained within plants owned and operated by the same legal entity

3.2.4

base polymer

polymer produced by the material supplier for the manufacture of the compound according to this document

3.2.5

recyclate

plastics material resulting from the recycling of pre-consumer and post-consumer plastics products

Note 1 to entry: Also referred to as “secondary raw material” or “recycled plastics” or “regenerate”.

Note 2 to entry: Recycling can be chemical, physical or mechanical

3.2.6

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).

3.3.1

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 megapascalMPa .

3.3.2

minimum required strength

MRS

value of σ_LPL at 20 °C and 50 years, rounded down to the next smaller value of the R10 series or the R20 series

Note 1 to entry: The R10 series conforming to ISO 3^[3] and the R20 series to ISO 497^[4].

3.3.3

design stress

σ_s

allowable stress for a given application at 20 °C that is derived from the MRS by dividing it by the coefficient C

Note 1 to entry: Design stress can be calculated using the following formula:

Note 2 to entry: It is expressed inmegapascal MPa .

3.3.4

design coefficient

C

coefficient with a value greater than one which takes into consideration service conditions as well as the properties of the components of a piping system other than those represented in the lower confidence limit

Note 1 to entry: Minimum design coefficients are defined in ISO 12162.

Note 2 to entry: There might be a need of additional service factors depending on the service conditions as described in annex F to calculate the overall design coefficient.

3.3.5

reference curves

minimum required hydrostatic strength curves

Note 1 to entry: The reference curves are shown in annexes A to E in this document

3.4.1

nominal pressure

PN

numerical designation used for reference purposes related to the mechanical characteristics of the components of a piping system.

Note 1 to entry: A pressure, in bar, with the numerical value of PN is identical with the pressure, PS, as defined by Reference [5] if both pressures are taken at 20 °C.

Note 2 to entry: For plastics piping systems conveying water, it corresponds to the maximum continuous operating pressure in bar, which can be sustained for water at 20 °C for 50 years, based on the following minimum design coefficient:

where σ_s is expressed in MPa;

3.4.2

hydrostatic stress

σ

stress induced in the wall of a pipe when an internal hydrostatic pressure is applied

Note 1 to entry: The hydrostatic stress is related to the applied internal hydrostatic pressure, in bar p, the wall thickness, e, at any point and the mean outside diameter, d_em, of a pipe and calculated using the following formula:

Note 2 to entry: Formula is applicable for pipes only.

Note 3 to entry: It is expressed in MPa .

The material from which the components are made shall either be PB, PE, PE-RT, PE-X, or PP, as applicable, to which are added those additives that are needed to facilitate the manufacture and the end-use of pipes, fittings, and valves conforming to this document.

The additives used shall be uniformly dispersed.

The additives shall not be dosed separately or together in quantities sufficient to impair the chemical and physical characteristics as specified in this document.

The material shall be evaluated according to ISO 9080 by analysis of sustained pressure tests carried out in accordance with ISO 1167‑1 and ISO 1167‑2. In addition, the material shall be classified in accordance with ISO 12162.

Conformity of the relevant material to the reference curves shall be proven according to the applicable annex of this document.

The figures related to the hydrostatic strength as given in Annex A for PB, Annex B for PE, Annex C for PE-TR, Annex E for PE-X and Annex F for PP shall be used as a reference only.

Only materials as defined in Clause 3.2 classified and verified in conformity to reference curves shall be used.

The mechanical and physical property requirements are specified in Annex A for PB, Annex B for PE, Annex C for PE-RT, Annex E for PE-X and Annex F for PP.

Material biobased or generated by a chemical recycling process can be used in case the mass balance is required, and the appropriate declaration is provided by the material manufacturer.

Where fittings and valves are manufactured from the same material as pipes, the material classification and verification of conformity to reference curves shall be the same as for pipes.

For the classification and verification of conformity to reference curves of a material intended only for the manufacture of fittings and valves, the test piece shall be an injection-moulded or extruded test piece in form of a pipe.

The use of the manufacturer's own reworked material obtained during the production and testing of products conforming this document is permitted in addition to the use of virgin material. Reworked material obtained from external sources and recyclate material shall not be used.

The critical pressure p_c determined in accordance with ISO 13477 S4 test shall be greater than 1,5 times the maximum operating pressure of the pipeline system.

For a pipeline systems carrying air or a compressible gas, for design purposes, the resistance of the material to the phenomenon known as rapid crack propagation shall be taken into account ISO 4437-1:2024 Annex C. The critical pressure p_c is dependent on the material, pipe diameter, and operating temperature.

The critical pressure p_c applied in accordance with ISO 13477 S4 test shall be greater than 1,5 times the MOP of the pipeline system.

Information provided by the pipe or material supplier shall be taken into account when designing an industrial pipeline system for the transport of air or a compressible gas.

ISO 4437‑2^[23] defines the MOP for Polyethylene (PE) pipe for gas application considering the RCP performance. PE 100 materials can be operated up to 10 bar at 0 °C depending on wall thickness.

Crosslinked polyethylene (PE-X) pipe produced in accordance with ISO 14531‑1 has been shown to be resistant to RCP at temperatures down to −50 °C.

Additional consideration shall be taken on the safety and the mechanical performance of the system in case of vacuum and gaseous applications due to potential risk of buckling, collapse or burst.

All components shall conform to the specific relevant International Standard(s). Alternative standards or technical specifications may be applied in cases where suitable International Standard(s) do not exist. In all cases, fitness for purpose of the components shall be demonstrated by the manufacturer.

Materials and constituent elements used in making the relevant component (including rubber, greases, and any metal parts as may be used) shall have comparable resistance to the external and internal environments as all other elements of the piping system according to this document.

Materials other than PB, PE, PE-RT, PE-X, or PP in contact with components conforming to this document shall not adversely affect the performance of the components or initiate stress cracking.

All metal parts susceptible to corrosion shall be adequately protected.

When dissimilar metallic materials are used which can be in contact with moisture, steps shall be taken to avoid the possibility of galvanic corrosion.

Sealing materials shall have no detrimental effects on the properties of the components, joints, and assemblies.

Greases or lubricants shall not exude onto fusion areas and shall not affect the long-term performance of materials conforming to this document.

When viewed without magnification, the internal and external surfaces of the components shall be smooth, clean, and free from scoring, cavities, and other surface defects to an extent that would prevent conformity to this International Standard. The components shall not contain visible impurities.

The colour of the components depends on the material used and shall be as specified in Annex A for PB, Annex B for PE, Annex C for PE-RT, Annex E for PE-X and Annex F for PP.

It should be ensured that any national standard on the colour coding of piping, relating to its purpose or contents, is taken into account for the location where the components are intended to be used.

Components for external above ground installations shall be manufactured with material resistant to UV radiation for the intended application or adequately protected against UV radiation by other means. For products which are usually stored outside in direct sunlight prior to installation, the effect of UV radiation shall be taken into account. To assess materials for resistance to UV radiation for storage purposes, pipe shall be subject to a cumulative radiant exposure of ≥3,5 GJ/m² in accordance with ISO 16871. Following this exposure, the pipe is assessed for any significant change in mechanical properties.

The effects of UV radiation may be disregarded for components that are neither used in external above-ground installations nor exposed to direct sunlight during storage by the manufacturer, distributor, or on the job site.

The dimension measurements shall be taken after minimum 24h the piping component has been manufactured.

Dimensions shall be measured in accordance with ISO 3126 at (23 ± 2) °C after being conditioned for at least 4 h unless specified otherwise in the relevant material annex.

Indirect measurement during the stage of production is allowed at shorter time periods providing that evidence is shown of correlation.

In the applicable Annexes the given figures are schematic sketches only, to indicate the relevant dimensions. They do not necessarily represent the manufactured component(s). The given dimensions shall be respected.

Dimensions not given in this document but considered important by the user shall be specified by the manufacturer.

At the point of manufacture the mean outside diameters, wall thicknesses and related tolerances shall conform to the annex A for PB, Annex B for PE, Annex C for PE-RT, Annex E for PE-X and Annex F for PP.

At the point of manufacture the out-of-roundness (ovality) and related tolerances shall conform to the annex A for PB, Annex B for PE, Annex C for PE-RT, Annex E for PE-X and Annex F for PP.

The permitted deviations from the nominal or declared angle for a nonlinear fitting shall be ±2° where the angle comprises the relevant change of axis of the flow through the fitting.

The laying lengths for fittings and valves shall be declared by the manufacturer.

NOTE Laying length is the amount of a run of pipe, measured along the centerline, that is replaced by a fitting.

Threads used for jointing piping components shall conform to ISO 7‑1. Where a thread is used as a fastening means for jointing a specific assembly (e.g. union nuts), a thread conforming to ISO 228-1^[6] should be used.

Mechanical fittings used for jointing shall conform to conform to ISO 17885 provided that their dimensions will give origin to joints in accordance with the dimensions of components.

Joint dimensions connecting valves shall conform to the relevant dimensions of pipes and fittings conforming to this document.

When butterfly valves are mechanically joined to a plastic piping system special attention shall be taken related to their full opening.

Components shall withstand the hydrostatic stress induced by internal hydrostatic pressure without bursting or leaking when tested in accordance with ISO 1167‑1, ISO 1167‑2, and ISO 1167‑3 and the test conditions as specified in Annex A for PB, Annex B for PE, Annex C for PE-RT and Annex F for PP.

The hydrostatic test pressure, p, expressed in bar, shall be determined for pipes using Formula (1):

(1)

where σ is the hydrostatic stress for PB, PE, PE-RT, PE-X, or PP conforming to the applicable annex of this document (see 5.2).

The hydrostatic test pressure, p, expressed in bar, shall be determined for fittings using Formula (2). For S and SDR respectively, the value of the corresponding pipe shall be taken:

(2)

The hydrostatic test pressure, p, expressed in bar, is defined for valves in ISO 16135, ISO 16136, ISO 16137, ISO 16138, ISO 16139, or ISO 21787, as applicable, depending on the valve type.

The physical characteristics of components made from PB, PE, PE-RT, PE-X, or PP shall conform to the applicable annex of this document.

Where fluids other than water are to be conveyed, the effect of a fluid that can affect the component material shall be considered.

The components shall withstand the mechanical, thermal, and chemical demands and the resistance shall be investigated under the expected operating conditions. A derating factor may be applicable.

Elastomer materials used in the manufacture of sealants shall be classified according to their chemical resistance to fluid liquids, depending on the application.

NOTE Guidance for the contact with chemicals is given in ISO/TR 10358 ^[7], ISO 4433-1 ^[8], ISO 4433-2 ^[9] and ISO/TR 7620^[10], or by the component manufacturer.

The tolerance on the electrical resistance of the fitting at 23 °C shall be stated by the manufacturer. The resistance shall be in between nominal resistance (–10 %) and nominal resistance [(+10 %) + 0,1 Ω].

NOTE 0,1 Ω is the assumed value of the contact resistance.

The surface finish of the terminal pins shall allow a minimum contact resistance to satisfy the resistance tolerance requirements.

The electrical protection that shall be provided during the fusion process depends on the voltage and wave form (AC or DC). Definitions of electrical circuits and applicable protections are found in the relevant IEC standards.

Electrofusion fittings are part of an electrical circuit when connected to the control units ^[11]

For voltages greater than 25 V, direct human contact with energized parts shall not be possible when the fitting is in the fusion cycle during assembly in accordance with the instructions of the manufacturers of the fittings and of the assembly equipment, as applicable.

When components made from the same material conforming to this document are jointed to each other, the pipes, fittings, valves, and the joints shall conform to the fitness of purpose of the system of the applicable annex of this document.

When testing assemblies (e.g. screwed joints, flanged joints. different pipe materials) made from components of dissimilar materials, the calculated testing pressure shall result from the use of the lower hydrostatic (hoop) stress applicable to all materials under test. The isochronous stress-strain-diagrams specified in Annex A for PB, Annex B for PE, Annex C for PE-RT, Annex E for PE-X and Annex F for PP shall be used to define the lower applicable hydrostatic (hoop) stress.

In case mechanical joints, if presents, fails under the lower applicable testing pressure, this last can be reduced until the testing process can be correctly carried out.

Materials conforming to Annex A for PB, Annex B for PE, Annex C for PE-RT and Annex F for PP shall be fusible. The fusion compatibility shall be demonstrated for each material.

If requested, the compound manufacturer could demonstrate the fusion compatibility.

The classification of pipes shall be based on the pipe series, S, or the standard dimension ratio, SDR, or the nominal pressure, PN, as applicable. Reference is made to ISO 4065.

The classification of fittings shall be based on the corresponding pipe together with the pipe series S or the standard dimension ratio, SDR, or the nominal pressure, PN, as applicable.

Valves shall be classified in accordance with the requirements of ISO 16135, ISO 16136, ISO 16137, ISO 16138, ISO 16139, or ISO 21787, as applicable.

For the design and installation of thermoplastic piping systems for industrial applications, see Annex F.

The manufacturer shall declare conformity to this document by marking the component in accordance with Clause 16.

Marking elements shall be printed or formed directly on the component or be on a label in such a way that after storage, weathering and handling, and the installation, legibility is maintained.

NOTE The manufacturer is not responsible for marking of the component being illegible due to actions caused during installation and use such as painting, scratching, covering, or by use of detergents, etc. unless agreed upon or specified by the manufacturer.

Marking shall not initiate cracks or other types of defects which adversely influence the performance of the component.

If printing is used, the colouring of the printed information shall differ from the basic colouring of the component.

The size of the marking shall be such that the marking is legible without magnification.

The minimum required marking of pipes shall conform to Table 2.

Pipes shall be marked at intervals of maximum 1 m, at least once per pipe.

Table 2 — Minimum required marking of pipes

The minimum required marking of fittings shall conform to Table 3, except for fittings with d_n ≤ 32 mm, for which the minimum required marking shall be directly on the fitting, as follows:

— manufacturer's name and/or trademark;

— nominal outside diameter(s);

— material;

— nominal wall thickness, e_n, or pipe series S or SDR or PN, as applicable.

Table 3 — Minimum required marking of fittings

Valves shall be marked in accordance with the requirements of ISO 16135, ISO 16136, ISO 16137, ISO 16138, ISO 16139, or ISO 21787, as applicable, depending on the valve type.

1. 
   (normative)
   
   Specific characteristics and requirements for industrial piping systems made from polybutene (PB)
   1. Material
      1. Material classification

The material as defined in Clause 3.2 in pipe form shall be evaluated in accordance with ISO 9080:2012 where internal pressure tests are made in accordance with ISO 1167-1 and ISO 1167-2 to find the σ_LPL values.

The σ_LPL values thus determined shall at least be as high as the corresponding values of the reference lines. Testing shall be carried out at temperatures stated below.

Temperatures: 20 °C; 60 °C to 82 °C; 95 °C; 110 °C.

NOTE 1 82 °C is equivalent to 180 °F, commonly used as a test temperature in ASTM standards.

PB shall have a minimum required strength, MRS, at least equal to 12,5 MPa.

The reference lines in this document are the ones of PB homopolymer. (PB-H)

• • 1. Material verification of conformity to reference curves

To prove conformance to the reference curves, one of the following methods shall be used

— mathematical method (ISO 9080):

the σ_LPL values, as determined by ISO 9080 in A.1.1, shall at least be as high as the corresponding values of the reference curves at all temperatures and times of relevance;

— graphical method:

The material shall be tested in accordance with 5.2 at 20 °C, 60 °C to 80 °C and 95 °C as well as at various hydrostatic (hoop) stresses in such a way that at each temperature, at least three failure times fall in each of the following time intervals.

— 10 h to 100 h;

— 100 h to 1 000 h;

— 1 000 h to 8 760 h;

— > 8 760 h.

In tests lasting more than 8 760 h, any time which is reached at a certain stress on or above the relevant reference curve is considered as failure time.

Conformance with the reference curves is demonstrated by plotting the individual experimental results on the graph. At least 97,5 % of them shall lie on or above the following reference curves.

The mathematical description of the reference curves are given by Formula (A.1) and Formula (A.2) for the temperature range 10 °C to 110 °C, the graphical representation is given in Figure A.1 also for the temperature range of 10 °C to 110 °C.

First branch (i.e. the left hand portion of the curves as shown in Figure A.1).

—   PB: (A.1)

Second branch (i.e. the right hand portion of the curves as shown in Figure A.1).

—   PB: (A.2)

NOTE The calculation for PB is based on ISO 12230^[13].

Key

X₁ time to failure, in hours (h)

X₂ time to failure, in years

Y hoop stress, in megapascal (MPa)

Figure A.1 — Minimum required hydrostatic strength curves for PB

The endpoints of curves in the graph (see Figure A.1) are given just as an example; the extrapolation time limit for a specific material (endpoints in the regression curves) has to be determined based on the method given in ISO 9080.

• • 1. Material characteristics

The material from which the components are manufactured shall conform to the requirements given in Table A.1.

Table A.1 — Material characteristics of PB

• • 1. Crystallization

Due to the slow crystallization, crystalline transformation, and shrinkage which takes places after PB compounds are cooled from the melt, physical and mechanical testing in accordance with A.4.1 and measurement of dimensions shall be delayed after extrusion or moulding.

• 1. General characteristics: Colour

Colour shall be agreed upon between manufacturer and purchaser.

• 1. Geometrical characteristics
     1. Dimensions of pipes
        1. Diameters and related tolerances

The mean outside diameter, d_em, and the related tolerances shall conform to Table A.2, appropriate to the tolerance grade, whereby the average value of the measurements of the outside diameter made at a distance of d_n and 0,1d_n from the end of the test pieces shall be within the tolerance range for d_em specified in Table A.2.

• • • 1. Out-of-roundness

If other values for the out-of-roundness of straight lengths than those given in Table A.2 are necessary, they shall be agreed upon between manufacturer and purchaser.

For coiled pipes, the maximum out-of-roundness shall be specified by agreement between manufacturer and purchaser.

Table A.2 — Mean outside diameters, related tolerances and out-of-roundness of pipes

Dimensions in millimetres

• • • 1. Wall thicknesses and related tolerances

The wall thickness, e, and the related tolerances shall conform to Table A.3.

Components intended to be welded shall have a minimum wall thickness of 1,9 mm.

Table A.3 — Wall thicknesses and related tolerances

Dimensions in millimetres

• • 1. Dimensions of fittings
       1. General

This Annex is applicable for the following types of fittings:

— socket fusion fittings;

— electrofusion fittings;

— flange adaptors and loose backing flanges;

— mechanical fittings.

• • • 1. Socket fusion fittings
         1. Types of socket fusion fittings

Socket fusion fittings (see Figure A.2) shall be classified in the following two types.

— Type A: Fittings intended to be used with pipes having dimensions as given in A.3.1 where no external machining of the pipe is required.

— Type B: Fittings intended to be used with pipes having dimensions as given in A.3.1 where machining of the outside surface of the pipe is necessary in accordance with the instructions of the manufacturer.

• • • • 1. Diameters and lengths of sockets

The nominal diameter(s), d_n, of a socket fusion fitting shall correspond to, and be designated by, the nominal outside diameter(s) of the pipe(s) for which it is designed.

The diameters and lengths of sockets for socket fusion fittings of type A shall conform to Table A.4. For socket fusion fittings of type B, the diameters and lengths of sockets shall conform to Table A.5.

Key

D₁ inside diameter of the socket mouth which comprises the mean diameter of the circle at the inner section of the extension of the socket with the plane of the socket mouth

D₂ mean inside diameter of the socket root which comprises the mean diameter of the circle in a plane parallel to the plane of the socket mouth and separated from it by a distance of L_1 min

D₃ minimum diameter of the flow channel (bore) through the body of a fitting

L_1 min minimum socket length which comprises the distance from the socket mouth to the shoulder

L_2 min minimum insertion length which comprises the depth of the penetration of the heated pipe end into the socket

R minimum radius at socket root

Figure A.2 — Diameters and lengths of socket fusion fittings

Table A.4 — Diameters and lengths of sockets for socket fusion fittings of type A

Dimensions in millimetres

Table A.5 — Diameters and lengths of sockets for socket fusion fittings of type B

Dimensions in millimetres

• • • • 1. Other dimensions

Other dimensions of socket fusion fittings shall be specified by the manufacturer.

• • • 1. Electrofusion fittings
         1. Dimensions of sockets of electrofusion fittings

The dimensions of sockets of electrofusion fittings (see Figure A.3) shall conform to Table A.6.

In the case of a fitting having sockets of different sizes (e.g. reduction), each socket shall conform to the requirements of the corresponding nominal diameter.

In case of using spigot end fittings, the outside tubular length of the fusion end shall allow the assembly with an electrofusion fitting.

Key

D₁ mean inside diameter in the fusion zone measured in a plane parallel to the plane of the mouth at a distance of L₃ + 0,5L₂ from that face

D₂ bore, which is the minimum diameter of the flow channel through the body of the fitting

L₁ depth of penetration of the pipe or male end of a spigot end fitting; in case of a coupling without stop, it is not greater than half the total length of the fitting

L₂ heated length within a socket as declared by the manufacturer, to be the nominal length of the fusion zone

L₃ distance between the mouth of the fitting and the start of the fusion zone as declared by the manufacturer to be the nominal unheated entrance length of the fitting (L₃ ≥ 5 mm)

Figure A.3 — Dimensions of sockets of electrofusion fittings

Table A.6 — Dimensions of sockets of electrofusion fittings

Dimensions in millimetres

The mean inside diameter of the fitting in the middle of the fusion zone (see D₁ in Figure A.3) shall be not less than d_n.

• • • • 1. Other dimensions

Other dimensions of electrofusion fittings shall be specified by the manufacturer.

• • • 1. Flange adaptors and loose backing flanges
         1. General

Flange adaptors and loose backing flanges shall conform to the following clauses.

Mating dimension for flange adaptors and backing ring drilled with different pattern are deemed to be in line with this document, example ASME B16.5^[14].

• • • • 1. Dimensions of flange adaptors for socket fusion

The dimensions of flange adaptors for socket fusion (see Figure A.4) shall conform to Table A.7.

Key

D_f1 outside diameter of flange adaptor

D_f2 outer diameter of the chamfer on shoulder

r_f radius of chamfer on shoulder

d_n nominal outside diameter of the corresponding pipe

h_f height of the flange adaptor shoulder

1 upper part of the figure: Jointing face of flat seal

2 lower part of the figure: Jointing face with O-ring grove

Figure A.4 — Dimensions of flange adaptors for socket fusion

Table A.7 — Dimensions of flange adaptors for socket fusion

Dimensions in millimetres

• • • • 1. Dimensions of loose backing flanges for use with flange adaptors for socket fusion

The dimensions of loose backing flanges for use with flange adaptors for socket fusion (see Figure A.5) shall conform to Table A.8.

Key

d_f1 inside diameter of flange

d_f2 pitch circle diameter of bolt holes

d_f3 outside diameter of flange

d_f4 diameter of bolt holes

r radius of flange

h thickness of backing ring

NOTE The thickness, h, of the loose backing flange is dependent on the material used.

Figure A.5 — Dimensions of loose backing flanges for use with flange adaptors for socket fusion

Table A.8 — Dimensions of loose backing flanges for use with flange adaptors for socket fusion

Dimensions in millimetres

• 1. Mechanical characteristics
     1. Mechanical characteristics of pipes and fittings

When tested as specified in Table A.9 using the indicated parameters, the components shall withstand the hydrostatic stress without bursting or leaking under the test conditions given in Table A.10.

Table A.9 — Requirements for internal pressure testing

Table A.10 — Test conditions for internal pressure testing

• • 1. Mechanical characteristics of valves

The valves shall conform to the requirements of ISO 16135, ISO 16136, ISO 16137, ISO 16138, ISO 16139 or ISO 21787, as applicable, depending on the valve type.

• 1. Physical characteristics
     1. Physical characteristics of pipes

When tested in accordance with the test methods as specified in Table A.11 using the indicated parameters, the pipe shall have physical characteristics conforming to the requirements given in Table A.11.

Table A.11 — Physical characteristics of pipes

• • 1. Physical characteristics of fittings

When tested in accordance with the test method as specified in Table A.12 using the indicated parameters, the fitting shall have physical characteristics conforming to the requirements given in Table A.12.

Table A.12 — Physical characteristics of fittings

• • 1. Physical characteristics of valves

In addition to the requirements of ISO 16135, ISO 16136, ISO 16137, ISO 16138, ISO 16139, or ISO 21787, as applicable, depending on the valve type, the physical characteristics of valves shall conform to A.5.2.

• 1. Fitness for purpose of the system

Fitness for purpose of the system shall be demonstrated on test pieces assembled.
These test pieces shall be assembled in accordance with the manufacturer quality plan and in accordance with clause 12.

Requirements for testing are specified in Table A.13.

Table A.13 — General requirements for fitness for purpose of the system

1. 
   (normative)
   
   Specific characteristics and requirements for industrial piping systems made from polyethylene (PE)
   1. Material
      1. General

This Annex is applicable to the following polyethylene designations:

— polyethylene (PE 80);

— polyethylene (PE 100):

— polyethylene raised crack resistance (PE 100-RC).

• • 1. Material classification and designation

The compound as defined in Clause 3.2 shall be evaluated in accordance with ISO 9080 on pipes. Compounds shall be designated by the type of PE material. The minimum required strength (MRS) shall conform to Table B.1 when tested in the form of pipe.

The compound shall be evaluated in accordance with ISO 9080 on pipes at least at three temperatures, where the first temperature is either 20 °C or 23 °C and the second temperature at 80 °C, and the third temperature is free between 30 °C and 70 °C, to find the σ_LPL. The MRS value shall be derived from the σ_LPL and the compound shall be classified by the compound manufacturer in accordance with ISO 12162.

At 80 °C, there shall be no knee detected in the regression curve at t < 5 000 h.

NOTE Testing has shown that for many compounds, no knee is detected before 1 year (8 760 h) at 80 °C.

The conformity of the designation of the compound to the classification given in Table B.1 shall be demonstrated.

The applicable PE shall have a minimum required strength, MRS, as given in Table B.1.

Table B.1 — MRS values of designated PE

• • 1. Material verification of conformity to reference curves

To prove conformance to the reference curves, one of the following methods shall be used:

— mathematical method (ISO 9080):

the σ_LPL values, as determined in B.1.2, shall at least be as high as the corresponding values of the reference curves at all temperatures and times of relevance;

— graphical method.

The material shall be tested in accordance with 5.2 at 20 °C or 23 °C, between 30 °C and 70 °C and 80 °C, as well as at various hydrostatic (hoop) stresses in such a way that at each temperature, at least three failure times fall in each of the following time intervals:

— 10 h to 100 h;

— 100 h to 1 000 h;

— 1 000 h to 8 760 h;

— > 8 760 h.

In tests lasting more than 8 760 h, any time which is reached at a certain stress on or above the relevant reference curve is considered as failure time.

Conformance with the reference curves is demonstrated by plotting the individual experimental results on the graph. At least 97,5 % of them shall lie on or above the following reference curves.

The mathematical description of the reference curves are given by Formula (B.1) to Formula (B.2) for the temperature range 10 °C to 80 °C, the graphical representations are given in Figure B.1 (PE 80), and Figure B.2 (PE 100 and PE 100-RC ) also for the temperature range of 10 °C to 80 °C.

First branch (i.e. the left hand portion of the curves as shown in Figure B.1 and Figure B.2,).

— PE 80: (B.1)

— PE 100 and PE 100-RC: (B.2)

Key

X₁ time to failure, in hours (h)

X₂ time to failure, in years

Y hoop stress, in megapascal (MPa)

Figure B.1 — Minimum required hydrostatic strength curves for PE 80

Key

X₁ time to failure, in hours (h)

X₂ time to failure, in years

Y hoop stress, in megapascal (MPa)

Figure B.2 — Minimum required hydrostatic strength curves for PE 100 and PE 100-RC

The endpoints of curves in the graphs (Figures B.1 to B.2) are given just as an example; the extrapolation time limit for a specific material (endpoints in the regression lines) shall be determined based on the method given in ISO 9080.

• • 1. Material characteristics

The material from which the components are manufactured shall conform to the requirements given in Table B.2 and Table B.3.

Table B.2 — Characteristics of the material in the form of granules

Table B.3 — Characteristics of the material in the form of pipe

• • 1. Type of pipe

The following two types of pipe are covered:

— PE pipe (outside diameter d_n), including any identification;

— PE pipes with co-extruded layers on either or both the outside and/or inside of the pipe (total outside diameter d_n) where all PE layers shall have the same MRS rating and the same PE designation (see Table B.1).

• 1. General characteristics — Colour

Components made from PE should preferably be black using compound. Other colours shall be agreed upon between the manufacturer and purchaser. National regulations can apply.

• 1. Geometrical characteristics
     1. Dimensions of pipes
        1. Diameters and related tolerances

The mean outside diameter, d_em, and the related tolerances shall conform to Table B.4, appropriate to the tolerance grade, whereby the average value of the measurements of the outside diameter made at a distance of d_n and 0,1d_n, from the end of the test pieces, shall be within the tolerance range for d_em as specified in Table B.4.

For socket fusion and electrofusion joints where the peeling/scaping techniques is used to prepare the pipe end for fusion, pipes with tolerances of Grade A given in ISO 11922‑1 shall be used.

For socket fusion joints where the peeling technique is not used, pipes with tolerances of Grade B given in ISO 11922‑1 shall be used.

• • • 1. Out-of-roundness

The out-of-roundness for straight lengths shall conform to Table B.4 when measured at the point of manufacture. If other values for the out-of-roundness than those given in Table B.4 are necessary, they shall be agreed upon between the manufacturer and purchaser.

For coiled pipes, the maximum out-of-roundness shall be specified by agreement between the manufacturer and purchaser.

Table B.4 — Mean outside diameters, related tolerances and out-of-roundness of pipes

Dimensions in millimetres

• • • 1. Wall thicknesses and related tolerances

The wall thickness, e, and the related tolerances shall conform to Table B.5.

Table B.5 — Wall thicknesses and related tolerances<Tbl_--></Tbl_-->

Dimensions in millimetres

• • 1. Dimensions of fittings
       1. General

Annex B is applicable for the following types of fittings:

— butt fusion fittings;

— socket fusion fittings;

— electrofusion fittings;

— flange adaptors and loose backing flanges;

— mechanical fittings.

• • • 1. Butt fusion fittings
         1. Outside diameters

The mean outside diameter, d_em, of the spigot end (see Figure B.4) over the length, L_b2 (see Table B.6) shall conform to B.3.1.1, except between the plane of the entrance face and the plane parallel to it, located at a distance not greater than 0,01d_n + 1 mm where a reduction of the outside diameter is permissible (e.g. for circumferential reversion).

• • • • 1. Out-of-roundness

The out-of-roundness of the spigot end (see Figure B.4) over the length, L_b2 (see Table B.6) shall conform to B.3.1.2.

• • • • 1. Wall thickness of the spigot end

The wall thickness, e, of the spigot end (see Figure B.3) over the length, L_b1, (see Table B.6) shall conform to B.3.1.3 except between the plane of the entrance face and the plane parallel to it, located at a distance not greater than 0,01d_n + 1 mm where a thickness reduction is permissible (e.g. for chamfered edge).

Key

L_b1 cut-back length of fusion end piece – it comprises the initial depth of the spigot end necessary for butt fusion or reweld and can be obtained by joining a length of pipe to the spigot end of the fitting provided that the wall thickness of the pipe is equal to E1 for its entire length.

L_b2 outside tubular length of fusion end piece – it comprises the initial length of the fusion end piece and shall allow the following (in any combination): the use of clamps required in the case of butt fusion; assembly with an electrofusion fitting; assembly with a socket fusion fitting; the use of a mechanical scraper.

Figure B.3 — Dimensions of spigot end for butt fusion fittings

Table B.6 — Dimensions of spigot ends for butt fusion fittings

Dimensions in millimetres

The minimum tubular lengths given in Table B.6 are too short for electrofusion joints, see clause B.3.2.4.1.

• • • • 1. Wall thickness of fitting body

The wall thickness, e, of the fitting body shall be at least equal to the minimum wall thickness of the corresponding pipe (see B.3.1.3).

• • • • 1. Other dimensions

Other dimensions of butt fusion fittings shall be specified by the manufacturer.

• • • 1. Socket fusion fittings
         1. Types of socket fusion fittings

Socket fusion fittings (see Figure B.5) shall be classified into the following two types.

— Type A: Fittings intended to be used with pipes having dimensions as given in B.3.1 where no external machining of the pipe is required.

— Type B: Fittings intended to be used with pipes having dimensions as given in B.3.1 where machining of the outside surface of the pipe is necessary in accordance with the instructions of the manufacturer.

Socket fitting PN rating is declared by the manufacturer and based on own technical documentation.

• • • • 1. Diameters and lengths of sockets

The nominal diameter(s), d_n, of a socket fusion fitting shall correspond to, and be designated by, the nominal outside diameter(s) of the pipe(s) for which it is designed. B.3.2.5.1

The diameters and lengths of sockets for socket fusion fittings of type A shall conform to Table B.7. For socket fusion fittings of type B, the diameters and lengths of sockets shall conform to Table B.8.

Key

D₁ inside diameter of the socket mouth which comprises the mean diameter of the circle at the inner section of the extension of the socket with the plane of the socket mouth

D₂ mean inside diameter of the socket root which comprises the mean diameter of the circle in a plane parallel to the plane of the socket mouth and separated from it by a distance of L_1 min

D₃ minimum diameter of the flow channel (bore) through the body of a fitting

L_1 min minimum socket length which comprises the distance from the socket mouth to the shoulder

L_2 min minimum insertion length which comprises the depth of penetration of the heated pipe end into the socket;

R maximum radius at socket root

Figure B.4 — Diameters and lengths of socket fusion fittings

Table B.7 — Diameters and lengths of sockets for socket fusion fittings of type A

Dimensions in millimetres

Table B.8 — Diameters and lengths of sockets for socket fusion fittings of type B

Dimensions in millimetres