Plastics piping systems for the supply of gaseous fuels - Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing — Part 5: Fitness for purpose of the system

ISO 16486-5:2012 specifies the requirements of fitness for purpose of the unplasticized polyamide (PA-U) piping system, intended to be buried and used for the supply of gaseous fuels. It also specifies the definitions of electrofusion and butt fusion joints. ISO 16486-5:2012 specifies the method of preparation of test piece joints and the tests to be carried out on these joints for assessing the fitness for purpose of the system under normal and extreme conditions. It also specifies the test parameters for the test methods to which it refers. ISO 16486 is applicable to PA-U piping systems the components of which are connected by fusion jointing and/or mechanical jointing. In conjunction with the other parts of ISO 16486, ISO 16486-5:2012 is applicable to PA-U fittings, their joints and to joints with components of PA-U.

Systèmes de canalisations en matières plastiques pour la distribution de combustibles gazeux — Systèmes de canalisations en polyamide non plastifié (PA-U) avec assemblages par soudage et assemblages mécaniques — Partie 5: Aptitude à l'emploi du système

General Information

Status
Withdrawn
Publication Date
03-Jun-2012
Withdrawal Date
03-Jun-2012
Current Stage
9599 - Withdrawal of International Standard
Completion Date
11-May-2021
Ref Project

Relations

Buy Standard

Standard
ISO 16486-5:2012 - Plastics piping systems for the supply of gaseous fuels - Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing
English language
20 pages
sale 15% off
Preview
sale 15% off
Preview

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 16486-5
First edition
2012-06-01
Plastics piping systems for the supply of
gaseous fuels — Unplasticized polyamide
(PA-U) piping systems with fusion
jointing and mechanical jointing —
Part 5:
Fitness for purpose of the system
Systèmes de canalisations en matières plastiques pour la
distribution de combustibles gazeux — Systèmes de canalisations
en polyamide non plastifié (PA-U) avec assemblages par soudage et
assemblages mécaniques —
Partie 5: Aptitude à l’emploi du système
Reference number
ISO 16486-5:2012(E)
©
ISO 2012

---------------------- Page: 1 ----------------------
ISO 16486-5:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 16486-5:2012(E)
Contents Page
Foreword .iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms, definitions, symbols and abbreviated terms . 2
3.1 Terms and definitions — General . 2
3.2 Terms and definitions for preparation of test assemblies by electrofusion . 2
4 Fitness for purpose . 5
4.1 Method of preparation of assemblies for testing . 5
4.2 Requirements for fitness for purpose . 5
Annex A (normative) Preparation of test assemblies by butt fusion .10
Annex B (normative) Preparation of test assemblies by electrofusion .13
Annex C (normative) Test methods for the assessment of fitness for purpose of transition fittings .18
Bibliography .20
© ISO 2012 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO 16486-5:2012(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 16486-5 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the
transport of fluids, Subcommittee SC 4, Plastics pipes and fittings for the supply of gaseous fuels.
This first edition of ISO 16486-5 cancels and replaces the first edition of ISO 22621-5:2010 which has been
technically revised.
ISO 16486 consists of the following parts, under the general title Plastics piping systems for the supply of
gaseous fuels — Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing:
ISO 16486 consists of the following parts, under the general title Plastics piping systems for the supply of
gaseous fuels — Unplasticized polyamide (PA-U) piping systems with fusion jointing and mechanical jointing:
— Part 1: General
— Part 2: Pipes
— Part 3: Fittings
— Part 5: Fitness for purpose of the system
— Part 6: Code of practice for design, handling and installation
iv © ISO 2012 – All rights reserved

---------------------- Page: 4 ----------------------
ISO 16486-5:2012(E)
Introduction
Thin wall thickness unplasticized polyamide (PA-U) pipes and solvent cement joints are used typically for low
pressures, while thicker wall thickness pipes and butt fusion, electrofusion or mechanical joints are typically
used for high pressures.
For technical and safety reasons, it is not possible to mix the components of the two types of piping system
(thin wall thickness pipes cannot be jointed by butt fusion or mechanical joints and vice versa). In particular,
solvent cement joints must not be used for jointing for high pressure piping systems.
So for the time being, the standardization programme dealing with unplasticized polyamide (PA-U) piping
systems for the supply of gaseous fuels is split into two series of International Standards, with one series
(ISO 17467) covering piping systems the components of which are connected by solvent cement jointing and
the other (ISO 16486) the components of which are connected by fusion jointing and/or mechanical jointing.
When more experience will be gained from the field, it might be reasonable to merge the ISO 17467 series and
the ISO 16486 series in one single series applicable to PA-U piping systems.
A similar series (ISO 17135) for fusion and mechanically jointed plasticized polyamide (PA-P) piping systems
is in preparation.
© ISO 2012 – All rights reserved v

---------------------- Page: 5 ----------------------
INTERNATIONAL STANDARD ISO 16486-5:2012(E)
Plastics piping systems for the supply of gaseous fuels —
Unplasticized polyamide (PA-U) piping systems with fusion
jointing and mechanical jointing —
Part 5:
Fitness for purpose of the system
1 Scope
This part of ISO 16486 specifies the requirements of fitness for purpose of the unplasticized polyamide (PA-U)
piping system, intended to be buried and used for the supply of gaseous fuels. It also specifies the definitions
of electrofusion and butt fusion joints.
This part of ISO 16486 specifies the method of preparation of test piece joints and the tests to be carried out
on these joints for assessing the fitness for purpose of the system under normal and extreme conditions. It also
specifies the test parameters for the test methods to which it refers.
ISO 16486 is applicable to PA-U piping systems the components of which are connected by fusion jointing
and/or mechanical jointing.
In conjunction with the other parts of ISO 16486, it is applicable to PA-U fittings, their joints and to joints with
components of PA-U.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are indispensable
for its application. For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
ISO 291, Plastics — Standard atmospheres for conditioning and testing
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 1167-4, Thermoplastics pipes, fittings and assemblies for the conveyance of fluids — Determination of the
resistance to internal pressure — Part 4: Preparation of assemblies
ISO 6259-1, Thermoplastics pipes — Determination of tensile properties — Part 1: General test method
ISO 13953, Polyethylene (PE) pipes and fittings — Determination of the tensile strength and failure mode of
test pieces from a butt-fused joint
ISO 13954, Plastics pipes and fittings — Peel decohesion test for polyethylene (PE) electrofusion assemblies
of nominal outside diameter greater than or equal to 90 mm
ISO 13955, Plastics pipes and fittings — Crushing decohesion test for polyethylene (PE) electrofusion assemblies
ISO 13956:2010, Plastics pipes and fittings — Decohesion test of polyethylene (PE) saddle fusion joints —
Evaluation of ductility of fusion joint interface by tear test
ISO 16486-1, Plastics piping systems for the supply of gaseous fuels — Unplasticized polyamide (PA-U) piping
systems with fusion jointing and mechanical jointing — Part 1: General
ISO 16486-2, Plastics piping systems for the supply of gaseous fuels — Unplasticized polyamide (PA-U) piping
systems with fusion jointing and mechanical jointing — Part 2: Pipes
© ISO 2012 – All rights reserved 1

---------------------- Page: 6 ----------------------
ISO 16486-5:2012(E)
ISO 16486-3, Plastics piping systems for the supply of gaseous fuels — Unplasticized polyamide (PA-U) piping
systems with fusion jointing and mechanical jointing — Part 3: Fittings
3 Terms, definitions, symbols and abbreviated terms
For the purposes of this document, the terms, definitions, symbols and abbreviated terms given in ISO 16486-1
and the following apply.
3.1 Terms and definitions — General
3.1.1
electrofusion joint
joint between a PA-U electrofusion socket or saddle fitting and a pipe or a spigot end fitting
NOTE The electrofusion fittings are heated by the Joule effect of the heating element incorporated at their jointing
surfaces, causing the material adjacent to them to melt and the pipe and fitting surfaces to fuse.
3.1.2
butt fusion joint (using heated tool)
joint made by heating the planed ends the surfaces of which match by holding them against a flat heating plate
until the PA-U material reaches fusion temperature, removing the heating plate quickly and pushing the two
softened ends against one another
3.1.3
fusion compatibility
ability of two unplasticized polyamide materials of the same type to be fused together to form a joint which
conforms to the performance requirements of this part of ISO 16486
3.1.4
transition fitting
fitting that makes a transition joint between a unplasticized polyamide (PA-U) piping and a metallic pipe
3.1.5
transition joint
joint at which two different piping materials (the PA-U and metal piping) are connected
3.1.6
anodeless riser
type of transition fitting which is designed to transport gas from an underground unplasticized polyamide (PA-
U) service line to above-ground steel piping
NOTE In an anodeless riser, the PA-U pipe is always the gas carrier, at least, in the below ground section.
3.2 Terms and definitions for preparation of test assemblies by electrofusion
3.2.1
reference time
t
R
theoretical fusion time indicated by the fitting manufacturer for the reference ambient temperature
NOTE See Annex B.
3.2.2
fusion energy
electrical energy supplied during the fusion-jointing cycle as measured at the terminals of the fitting at a given
ambient temperature, T , and for electrical parameters whose values lie within the tolerance ranges declared
a
by the manufacturer
NOTE 1 The fitting manufacturer is generally required to state in the technical file any variations in fusion energy input
required as a function of the ambient temperature in the range T to T .
min max
2 © ISO 2012 – All rights reserved

---------------------- Page: 7 ----------------------
ISO 16486-5:2012(E)
NOTE 2 Where applicable, energy measurement should exclude the effect of terminal contact resistance.
NOTE 3 See Annex B.
3.2.3
reference energy
energy supplied to a fitting having a nominal electrical resistance and using the nominal fusion parameters
defined by the manufacturer at the reference ambient temperature, T
R
NOTE See Annex B.
3.2.4
maximum energy
maximum value of the fusion energy supplied for jointing at a given ambient temperature, T
a
NOTE See Annex B.
3.2.5
minimum energy
minimum value of the fusion energy supplied for jointing at a given ambient temperature, T
a
NOTE See Annex B.
3.2.6
nominal energy
nominal energy supplied for jointing at given ambient temperature, T
a
NOTE See Annex B.
3.2.1 Symbols
Application Symbol Description Unit
Symbols used in more than one e nominal pipe wall thickness mm
n
a
phase of the fusion-jointing cycle
d nominal external diameter of the pipe
n
p pressure applied to the butt fusion joint interface
t duration of each phase in the fusion cycle
T normal temperature (23 ± 2) °C °C
nor
T maximum permissible ambient temperature °C
max
T minimum permissible ambient temperature °C
min
a
Symbols for joint geometry Δ misalignment between the pipes or fittings to be mm
a
butt fused, expressed in terms of the difference, in
millimetres, between, the external diameters
Δ clearance between the fusion faces, expressed in terms mm
w
of the gap, in millimetres, between the prepared faces
ab
Symbols for ambient temperature T ambient temperature at which the joint is made °C
a
T
Symbols butt fusion cycle heater-plate temperature, measured in the zone of the °C
a
parameters heater-plate surface in contact with the pipe or spigot
ends to be butt fused
— General
— Phase 1: heating p interface pressure during the heating phase, i.e. the MPa
1
pressure applied in the contact zone
B initial bead width taken as the bead width at the end of mm
1
the heating phase
t heating time, taken as the time necessary to obtain a s
1
bead of width B in the joint region during the heating
1
phase
© ISO 2012 – All rights reserved 3

---------------------- Page: 8 ----------------------
ISO 16486-5:2012(E)
Application Symbol Description Unit
— Phase 2: heat soak p pressure between the heater plate and the pipe or spigot MPa
2
ends during the heat soak phase
t duration of internal heating during the heat soak phase s
2
— Phase 3: withdrawal of heater t time between the moment when the heater plate is s
3
plate removed from the pipe and/or spigot ends and the
moment when the pipe and/or spigot ends are placed in
contact with each other
— Phase 4: pressure increase t time required to establish the butt fusion pressure s
4
— Phase 5: butt fusion p pressure applied to the contact zone during the butt MPa
5
fusion phase
t time during which the assembly remains under the butt s
5
fusion pressure in the machine
— Phase 6: cooling t cooling time during which the butt fused assembly is not min
6
subjected to any rough handling; this cooling can take
place outside the machine
B bead width obtained at the end of the cooling phase mm
2
Symbols for the preparation of test D mean inside diameter of the fusion zone of a fitting in the mm
im
c
assemblies by electrofusion radial plane located a distance L + 0,5L from the face
3 2
of the fitting socket
D maximum theoretical value of D as declared by the mm
im,max im
fitting manufacturer
D maximum inside diameter of the fusion zone of the fitting mm
i,max
D minimum inside diameter of the fusion zone of the fitting mm
i,min
d outside diameter of a pipe or fitting spigot mm
e
d mean outside diameter of a pipe or fitting spigot in mm
em
conformance with ISO 16486-2 and ISO 16486-3,
as applicable, and calculated from the measured
circumference
d mean outside diameter of a pipe or fitting spigot mm
emp
after preparation for assembly with the outer layer
removed by scraping or peeling and calculated from the
circumference measured in a radial plane coincident
with the centre of the fusion zone at a distance
L + 0,5L from the face of the fitting socket after
3 2
assembly
e nominal wall thickness of the pipe mm
n
e depth of scraping or the thickness of material removed mm
s
from the pipe surface by peeling
L nominal length of the fusion zone as indicated by the mm
2
fitting manufacturer
L nominal distance from the face of the fitting socket to the mm
3
leading edge of the fusion zone
a
See Annex A.
b
The ambient temperature may vary from the minimum temperature, T , to the maximum temperature, T , as defined by
min max
agreement between the manufacturer and the purchaser.
c
See Figure B.1; see Annex B.
4 © ISO 2012 – All rights reserved

---------------------- Page: 9 ----------------------
ISO 16486-5:2012(E)
4 Fitness for purpose
4.1 Method of preparation of assemblies for testing
4.1.1 General
The joints shall be made by using pipes conforming to ISO 16486-2 or fittings conforming to ISO 16486-3.
Test pieces for pressure test shall be closed with pressure-tight, end-load-bearing end caps, plugs or flanges,
which shall be provided with connections for the entry of water and release of air.
4.1.2 Butt fusion joints
PA-U pipes and spigot end fittings intended to be used for jointing by butt fusion shall be prepared and
assembled in accordance with Annex A.
4.1.3 Electrofusion jointing
PA-U pipes and fittings intended to be used for jointing by electrofusion shall be prepared and assembled in
accordance with Annex B.
For joints with electrofusion socket fittings and joints with electrofusion saddle fittings, test joints shall be
prepared to check the fitness for purpose of the fittings under extreme jointing conditions.
For joints with electrofusion saddle fittings, the electrofusion saddle fitting shall be fused to the pipe, while it
is pneumatically pressurized to the allowable maximum operating pressure. The pipe shall be cut immediately
after the manufacturer-prescribed cooling time has elapsed.
These joints with electrofusion saddle fitting should be prepared taking national safety regulations into
consideration.
For straight equal electrofusion socket fittings (couplers), test joints on selected diameters out of the product
range shall be prepared with a gap of 0,05d between the pipe end and the maximum theoretical depth of
n
penetration of the fitting, where for diameters greater than 225 mm, the adjoining pipes shall be arranged to
provide the maximum angular deflection possible for the fitting, limited to 1,5°.
4.2 Requirements for fitness for purpose
4.2.1 Fitness for purpose for butt fusion joints
4.2.1.1 Under normal conditions — Ambient temperature 23 °C
For the assessment of fitness for purpose under normal conditions, butt fusion joints shall have the characteristic
of tensile strength conforming to the requirement given in Table 5, using the parameters as specified in Annex
A, Table A.2 and Table A.3, at an ambient temperature of (23 ± 2) °C and the scheme listed in Table 1.
© ISO 2012 – All rights reserved 5

---------------------- Page: 10 ----------------------
ISO 16486-5:2012(E)
Table 1 — Scheme for butt fusion joints
Pipe
Pipe/spigot end fitting
PA-U 11 160 PA-U 11 180 PA-U 12 160 PA-U 12 180
a
PA-U 11 160 X X Jointing not allowed Jointing not allowed
a
PA-U 11 180 X X Jointing not allowed Jointing not allowed
a
PA-U 12 160 Jointing not allowed Jointing not allowed X X
a
PA-U 12 180 Jointing not allowed Jointing not allowed X X
The table should be interpreted as follows: as an example, for a pipe or a spigot end fitting made from a PA-U 11 160
compound, a joint should be tested with a pipe made from PA-U 11 160 compound. When requested by the purchaser
or end user, for mixed compound joints, test pieces should be used incorporating PA-U 11 160 and PA-U 11 180
compounds.
a
Only when requested by the purchaser or end user.
The pipe manufacturer shall declare, according to 4.2.1.1, which pipes from his own product range conforming
to ISO 16486-2 are compatible to each other for butt fusion.
The fitting manufacturer shall declare, according to 4.2.1.1 the SDR range and MRS values of pipes conforming
to ISO 16486-2 to which his fittings conforming to ISO 16486-3 can be fused by using the same procedures
(e.g. times, temperatures, fusion pressures) to conform to this part of ISO 16486. If there is a need for deviation
in fusion procedures the fitting manufacturer shall state this clearly.
4.2.1.2 Under extreme conditions
For butt fusion joints, the characteristics to be examined for fitness for purpose under extreme conditions shall
conform to Table 2.
Table 2 — Relation between the joints and fitness for purpose characteristics
Butt fusion joint Associated characteristics
Both components of the joint: same MRS and same SDR Hydrostatic strength
a
Joint: minimum and maximum condition (80 °C, 165 h)
Both components of the joint: same MRS and same SDR Tensile strength for butt fusion joint
Joint: minimum and maximum condition
a
As specified in Annex A concerning misalignment [A.5 a)] and the limit values of fusion parameters (Table A.4).
When tested in accordance with the test methods as specified in Table 5 using the indicated parameters, the
joints shall have characteristics conforming to the requirements given in Table 5.
The fitting manufacturer shall declare according to Table 2, as applicable, the fitness for purpose under extreme
conditions of his fittings.
The pipe manufacturer shall declare according to Table 2 the fitness for purpose under ex
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.