ISO/TS 16422-3:2023

TECHNICAL ISO/TS
SPECIFICATION 16422-3
First edition
2023-06
Pipes and joints made of oriented
unplasticized poly(vinyl chloride)
(PVC-O) for the conveyance of water
under pressure —
Part 3:
Fittings
Tubes et assemblages en poly(chlorure de vinyle) non plastifié orienté
(PVC-O) pour le transport de l'eau sous pression —
Partie 3: Raccords
Reference number
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Symbols . 3
5 Material. 5
5.1 General . 5
5.2 Density . 5
5.3 Orientation factor . 5
6 General characteristics . 5
6.1 Appearance . 5
6.2 Colour . 5
6.3 Opacity . 6
6.4 Classification of fittings . . 6
7 Geometrical characteristics . 6
7.1 Design lengths, bend radii and angles . 6
7.2 Measurement of dimensions . 6
7.3 Nominal outside diameters and wall thickness . 6
7.4 Fittings with integral sockets with elastomeric sealing ring type . 6
8 Pressure and operating temperature . 7
8.1 Selection of nominal pressure for water up to and including 25 °C . 7
8.2 Determination of the allowable operating pressure for water up to 45 °C . 7
9 Mechanical characteristics — Resistance to hydrostatic pressure .7
10 Physical characteristics .7
11 Sealing rings .8
12 Performance requirements . .8
13 Marking . . 8
13.1 General . 8
13.2 Minimum required marking . . 8
13.3 Additional marking. 9
Annex A (normative) Determination of long-term hydrostatic strength .10
Annex B (normative) Determination of circumferential orientation factor .12
Annex C (informative) Recommended dimensions of PVC-O fittings .14
Bibliography .19
iii
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for
the transport of fluids, Subcommittee SC 2, Plastics pipes and fittings for water supplies.
A list of all parts in the ISO 16422 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.
iv
Introduction
Molecular orientation of thermoplastics results in the improvement of physical and mechanical
properties. Orientation is carried out at temperatures well above the glass transition temperature.
Orientation of PVC-U pipe-material can be induced by different processes.
In general, the following production process is common. A thick-wall tube is extruded (feedstock) and
conditioned at the desired temperature. The orientation process is activated in circumferential and
axial directions under controlled conditions.
After the orientation process, the pipe is cooled down quickly to ambient temperature.
The orientation of the molecules creates a laminar structure in the material of the pipe wall. This
structure gives the ability to withstand brittle failure emanating from minor flaws in the material
matrix or from scratches at the surface of the pipe wall.
Improved hoop strength allows reduced wall thickness with material and energy savings. Improved
resistance to impact and fatigue also result.
The classification depends on the material compound/formulation and stretch ratios used. Therefore,
with the classification, these characteristics can be specified or determined.
The ISO 16422 series, of which this document is Part 3, specifies the requirements for a piping system
made from oriented unplasticized poly(vinyl chloride) (PVC-O) and its components. The piping system
is intended to be used for water supply, pressurized drainage and sewerage and irrigation systems to
be used underground or above ground where protected to direct sunlight.
In respect of potential adverse effects on the quality of water intended for human consumption, caused
by the products covered by this document, the following points are relevant:
— this document provides no information as to whether or not the products can be used without
restriction;
— requirements and test methods for PVC-O material and components, other than fittings, are specified
in ISO 16422-1 and ISO 16422-2. For other components (not manufactured from PVC-O) reference is
made to the following documents: ISO 1452-3 (PVC-U) and EN 12842 (Cast Iron). Characteristics for
fitness for purpose (mainly for joints) are specified in ISO 16422-5.
The future documents ISO 16422-1, ISO 16422-2 and ISO 16422-5 are intended to cancel and replace
ISO 16422:2014.
This document is a completely new part of the ISO 16422 series since PCV-O fittings were not included
in ISO 16422:2014.
This document is specifically focussed on fittings, as opposed to more general specifications, which are
now covered in the various other parts of the ISO 16422 series.
v
TECHNICAL SPECIFICATION ISO/TS 16422-3:2023(E)
Pipes and joints made of oriented unplasticized poly(vinyl
chloride) (PVC-O) for the conveyance of water under
pressure —
Part 3:
Fittings
1 Scope
This document specifies the characteristics of solid-wall oriented unplasticized poly(vinyl chloride)
(PVC-O) fittings for piping systems intended to be used underground or above ground where protected
from direct sunlight, for water supply, buried drainage, sewerage, treated wastewater and irrigation
under pressure. This document is applicable to double sockets, repair couplings, reducers and to non-
end load bearing elbows only. This document is not applicable to tees, flange adaptors, etc.
NOTE For double sockets, repair couplings, and reducers, there are no special fittings designs for end-load
bearing applications. However, restrained gaskets can be used for end-load bearing applications. In this case, the
requirements of ISO 16422-5 are applicable.
This document also specifies the test parameters for the test methods referred to in this document.
In conjunction with ISO 16422-1 and ISO 16422-5, this document is applicable to oriented PVC-O pipes
with or without an integral socket, intended to be used for the following:
a) water mains and services lines;
b) conveyance of water for both outside and inside buildings;
c) drainage, sewerage and treated wastewater under pressure;
d) irrigation under pressure.
This document is applicable to piping systems intended for the supply of water under pressure up to
and including 25 °C (cold water), intended for human consumption and for general purposes as well as
for wastewater
...