ISO 8085-3:2001
(Main)Polyethylene fittings for use with polyethylene pipes for the supply of gaseous fuels — Metric series — Specifications — Part 3: Electrofusion fittings
Polyethylene fittings for use with polyethylene pipes for the supply of gaseous fuels — Metric series — Specifications — Part 3: Electrofusion fittings
Raccord en polyéthylène pour utilisation avec des tubes en polyéthylène pour la distribution de combustibles gazeux — Série métrique — Spécifications — Partie 3: Raccords électrosoudables
General Information
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Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 8085-3
First edition
2001-09-01
Corrected version
2004-09-15
Polyethylene fittings for use with
polyethylene pipes for the supply of
gaseous fuels — Metric series —
Specifications —
Part 3:
Electrofusion fittings
Raccords en polyéthylène pour utilisation avec des tubes en polyéthylène
pour la distribution de combustibles gazeux — Série métrique —
Spécifications —
Partie 3: Raccords électrosoudables
Reference number
ISO 8085-3:2001(E)
©
ISO 2001
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ISO 8085-3:2001(E)
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ii © ISO 2001 – All rights reserved
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ISO 8085-3:2001(E)
Contents Page
Foreword . iv
1 Scope. 1
2 Normative references. 1
3 Terms and definitions. 3
4 Symbols. 5
5 Material. 6
6 General requirements. 10
7 Geometrical characteristics. 11
8 Mechanical characteristics. 13
9 Physical characteristics. 16
10 Technical file. 16
11 Marking. 16
12 Packaging. 17
Annex A (informative) Examples of typical connector sockets for electrofusion fittings . 18
Annex B (normative) Formulae for calculating the equivalent dimensions of non-metric fitting series . 21
Annex C (normative) Short-term pressure test method . 22
Annex D (normative) Tensile test for fitting/pipe assemblies. 24
Bibliography. 25
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ISO 8085-3:2001(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 3.
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 part of ISO 8085 may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
International Standard ISO 8085-3 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.
ISO 8085 consists of the following parts, under the general title Polyethylene fittings for use with polyethylene pipes
for the supply of gaseous fuels — Metric series — Specifications:
— Part 1: Fittings for socket fusion using heated tools
— Part 2: Spigot fittings for butt fusion, for socket fusion using heated tools and for use with electrofusion fittings
— Part 3: Electrofusion fittings
Annexes B, C and D form a normative part of this part of ISO 8085. Annex A is for information only.
In this corrected version of ISO 8085-3:2001, the reference to Table 5 in 7.2.2.2 b) has been corrected to read
“conform to Table 4…”.
In addition, Clause 2 (normative references) has been updated by inserting the years of publication of ISO 9080,
ISO 18553 and EN 682.
Users should further note that normative reference ASTM D 4019-94 (cited in Table 1) has been withdrawn without
replacement.
iv © ISO 2001 – All rights reserved
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INTERNATIONAL STANDARD ISO 8085-3:2001(E)
Polyethylene fittings for use with polyethylene pipes for the supply
of gaseous fuels — Metric series — Specifications —
Part 3:
Electrofusion fittings
1 Scope
This part of ISO 8085 specifies the requirements for polyethylene (PE) electrofusion fittings intended to be used
with PE pipes and fittings for the supply of gaseous fuels.
In addition, it specifies some general properties of the material from which these fittings are made.
This part of ISO 8085 also lays down requirements for dimensions and performance of such fittings.
It is applicable to electrofusion fittings designed to be fusion-jointed to PE pipes conforming to ISO 4437, and to
spigot fittings conforming to ISO 8085-2.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this part of ISO 8085. For dated references, subsequent amendments to, or revisions of, any of these publications
do not apply. However, parties to agreements based on this part of ISO 8085 are encouraged to investigate the
possibility of applying the most recent editions of the normative documents indicated below. For undated
references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain
registers of currently valid International Standards.
ISO 3:1973, Preferred numbers — Series of preferred numbers
ISO 497:1973, Guide to the choice of series of preferred numbers and of series containing more rounded values of
preferred numbers
ISO 1133:1997, Plastics — Determination of the melt mass-flow rate (MFR) and the melt volume-flow rate (MVR) of
thermoplastics
ISO 1167:1996, Thermoplastics pipes for the conveyance of fluids — Resistance to internal pressure — Test
method
ISO 1183 (all parts), Plastics — Methods for determining the density of non-cellular plastics
ISO 1872-1:1993, Plastics — Polyethylene (PE) moulding and extrusion materials — Part 1: Designation system
and basis for specifications
1)
ISO 3126:— , Plastics piping systems — Plastics piping components — Measurement and determination of
dimensions
1) To be published. (Revision of ISO 3126:1974)
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ISO 8085-3:2001(E)
ISO 4437:1997, Buried polyethylene (PE) pipes for the supply of gaseous fuels — Metric series — Specifications
ISO 6964:1986, Polyolefin pipes and fittings — Determination of carbon black content by calcination and pyrolysis —
Test method and basic specification
ISO 8085-2:2001, Polyethylene fittings for use with polyethylene pipes for the supply of gaseous fuels — Metric
series — Specifications — Part 2: Spigot fittings for butt fusion, for socket fusion using heated tools and for use
with electrofusion fittings
ISO 9356:1989, Polyolefin pipe assemblies with or without jointed fittings — Resistance to internal pressure — Test
method
ISO 9080:2003, Plastics piping and ducting systems — Determination of the long-term hydrostatic strength of
thermoplastics materials in pipe form by extrapolation
ISO/TR 10837:1991, Determination of the thermal stability of polyethylene (PE) for use in gas pipes and fittings
ISO/TS 10839:2000, Polyethylene pipes and fittings for the supply of gaseous fuels — Code of practice for design,
handling and installation
ISO 11413:1996, Plastics pipes and fittings — Preparation of test piece assemblies between a polyethylene (PE)
pipe and an electrofusion fitting
ISO 12162:1995, Thermoplastics materials for pipes and fittings for pressure applications — Classification and
designation — Overall service (design) coefficient
ISO 12176-2:2000, Plastics pipes and fittings — Equipment for fusion jointing polyethylene systems — Part 2:
Electrofusion
ISO 13477:1997, Thermoplastics pipes for the conveyance of fluids — Determination of resistance to rapid crack
propagation (RCP) — Small-scale steady-state test (S4 test)
ISO 13478:1997, Thermoplastics pipes for the conveyance of fluids — Determination of resistance to rapid crack
propagation (RCP) — Full-scale test (FST)
ISO 13479:1997, Polyolefin pipes for the conveyance of fluids — Determination of resistance to crack propagation —
Test method for slow crack growth on notched pipes (notch test)
ISO 13951:2001, Plastics piping systems — Test method for the resistance of polyolefin pipe/pipe or pipe/fitting
assemblies to tensile loading
ISO 13954:1997, Plastics pipes and fittings — Peel decohesion test for polyethylene (PE) electrofusion assemblies
of nominal outside diameter greater than or equal to 90 mm
ISO 13955:1997, Plastics pipes and fittings — Crushing decohesion test for polyethylene (PE) electrofusion
assemblies
ISO 13957:1997, Plastics pipes and fittings — Polyethylene (PE) tapping tees — Test method for impact resistance
ISO 18553:2002, Method for the assessment of the degree of pigment or carbon black dispersion in polyolefin
pipes, fittings and compounds
ASTM D 4019-94, Standard Test Method for Moisture in Plastics by Coulometric Regeneration of Phosphorus
Pentoxide
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ISO 8085-3:2001(E)
EN 682:2002, Elastomeric seals — Materials requirements for seals used in pipes and fittings carrying gas and
hydrocarbon fluids
EN 12117:1997, Plastics piping systems — Fittings, valves and ancillaries — Determination of gaseous flow
rate/pressure drop relationships
IEC 60529:2001, Degrees of protection provided by enclosures (IP Code)
3 Terms and definitions
For the purposes of this part of ISO 8085, the following terms and definitions apply.
3.1 Geometrical definitions
3.1.1
nominal diameter of a fitting
d
n
the nominal diameter of a fitting is taken as the nominal diameter of the corresponding pipe series
3.1.2
nominal wall thickness of a fitting
e
n
the nominal wall thickness of a fitting is taken as the nominal wall thickness of the corresponding pipe series
3.1.3
mean inside diameter
arithmetic mean of at least two inside diameters measured at right angles to each other in transverse planes
3.1.4
out-of-roundness of a socket
maximum inside diameter minus the minimum inside diameter of the socket, measured in the same plane, parallel
to the plane of the mouth
3.1.5
maximum out-of-roundness of a socket
greatest value of the out-of-roundness between the plane of the mouth and a plane separated from it by a distance
L (the design penetration depth)
1
3.1.6
standard dimension ratio of a fitting
SDR
quotient of the nominal outside diameter and the nominal wall thickness
d
n
SDR =
e
n
3.1.7
wall thickness of a fitting
E
wall thickness at any point of the body of the fitting which could be subjected to the full stress induced by the
pressure of the gas in the piping system
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ISO 8085-3:2001(E)
3.2 Material definitions
3.2.1
virgin material
thermoplastics material in a form such as granules or powder which has not been previously processed other than
for compounding and to which no reprocessable or recyclable materials have been added
3.2.2
reprocessable material
thermoplastics material prepared from clean unused rejected pipes, fittings or valves, produced in a manufacturer’s
plant by a process such as injection-moulding or extrusion, which will be reprocessed in the same plant
NOTE Such material may include trimmings from the production of such pipes, fittings and valves.
3.2.3
compound
homogenous mixture of base polymer (PE) and additives, e.g. anti-oxidants, pigments and UV-stabilizers, at
concentrations necessary for the particular application
3.3 Definitions related to material characteristics
3.3.1
lower confidence limit
s
lcl
quantity with the dimensions of stress, in megapascals, which can be considered as a property of the material and
represents the 97,5 % lower confidence limit of the mean long-term hydrostatic strength at 20 °C for 50 years
determined by pressurizing internally with water
3.3.2
overall service (design) coefficient
C
overall coefficient, with a value larger than 1,0, 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
NOTE For gas applications, C can have any value equal to or greater than 2,0.
3.3.3
minimum required strength
MRS
the value of s rounded down to the next lower value in the R 10 series when s is less than 10 MPa, or to the
lcl lcl
next lower value in the R 20 series when s is greater than or equal to 10 MPa
lcl
NOTE The R 10 and R 20 series are the Renard number series as defined in ISO 3 and ISO 497.
3.3.4
melt mass-flow rate
MFR
value relating to the viscosity of molten thermoplastic material at a specified temperature and rate of shear
3.4 Definitions related to service conditions
3.4.1
gaseous fuel
2)
any fuel which is in the gaseous state at a temperature of + 15 °C and a pressure of 1 bar
5 2
2) 1 bar = 10 N/m = 0,1 MPa
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ISO 8085-3:2001(E)
3.4.2
maximum operating pressure
MOP
maximum effective pressure of the gas in a piping system, expressed in bars, which is allowed in continuous use
NOTE It takes into account the physical and the mechanical characteristics of the components of a piping system and is
given by the equation:
20¥ MRS
MOP =
C¥-(SDR 1)
3.5 Definitions specific to the design of electrofusion fittings
3.5.1
electrofusion socket fitting
polyethylene (PE) fitting which contains one or more integral heating elements that are capable of transforming
electrical energy into heat to produce a fusion joint with a spigot-end or a pipe
3.5.2
electrofusion saddle fitting
polyethylene (PE) fitting (top-loading or wrap-round) which contains one or more integral heating elements that are
capable of transforming electrical energy into heat to produce a fusion joint with a pipe
3.5.3
tapping tee
electrofusion saddle fitting which contains an integral cutter designed to cut through the pipe wall
NOTE The cutter remains in the body of the saddle after installation.
3.5.4
branch saddle
electrofusion saddle fitting which requires an ancillary cutting tool to drill a hole in the adjoining main pipe
3.5.5
U-regulation
control of the energy supplied, during fusion-jointing of an electrofusion fitting, by regulating the voltage
3.5.6
I-regulation
control of the energy supplied, during fusion-jointing of an electrofusion fitting, by regulating the current
4 Symbols
4.1 Symbols for electrofusion socket fittings
The dimensions and the main symbols used in this part of ISO 8085 are shown in Figure 1, where
D is the mean inside diameter in the fusion zone, i.e. the mean inside diameter measured in a plane parallel to
1
the plane of the mouth at a distance of L + 0,5L from the plane of the mouth.
3 2
D is the minimum bore, i.e. the minimum diameter of the flow channel through the body of the fitting.
2
L is the design penetration depth of the pipe or of the male end of a spigot fitting.
1
L is the nominal length of the fusion zone, corresponding to the heated length.
2
L is the nominal unheated entrance length of the fitting, i.e. the distance between the mouth of the fitting and the
3
near end of the fusion zone.
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ISO 8085-3:2001(E)
Figure 1 — Socket dimensions
4.2 Symbols for electrofusion tapping tees
The main symbols used for tapping tees are shown in Figure 2, where
h is the height of the service pipe, i.e. the distance between the axis of the main pipe and the axis of the service
pipe.
L is the width of the tapping tee, i.e. the distance between the axis of the main pipe and the plane of the mouth
of the service pipe.
H is the height of the tapping tee, i.e. the distance from the top of the main pipe to the top of the tapping tee.
5 Material
5.1 Technical data
The technical data referred to in Table 1 concerning the materials used shall be made available by the fitting
manufacturer.
Any change in the choice of materials affecting the quality shall require fresh type-testing of the fitting in
accordance with clause 8.
5.2 Compound
The compound from which the fitting is produced shall be polyethylene which shall be made by adding only those
additives necessary for the manufacture and end use of fittings conforming to this specification and for their fusion
jointing.
All additives shall be uniformly dispersed. The additives shall not have a negative influence on the performance
with respect to fusability.
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ISO 8085-3:2001(E)
Figure 2 — Tapping tee dimensions
5.3 Reprocessable material
Only clean reprocessable material generated from a manufacturer’s own production of fittings to this specification
may be used, and it shall be derived from the same resin as used for the relevant production.
5.4 Characteristics of the compound
The fittings shall be made of
a) virgin material,
b) reprocessable material or
c) a combination of virgin and reprocessable material.
The PE compound from which the fitting is manufactured shall conform to the requirements given in Table 1.
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ISO 8085-3:2001(E)
a)
Table 1 — Characteristics of the PE compound
Property Units Requirement Test parameters Test method
3
Density W 930 (base polymer) 23 °C ISO 1183, ISO 1872-1
kg/m
Melt mass-flow rate g/10 min 190 °C/5 kg ISO 1133:1997
± 20 % of value declared by compound
(set of conditions T)
producer
b
Thermal stability minutes > 20 ISO/TR 10837
200 °C
Volatile-matter content mg/kg u 350 ISO 4437:1997, annex A
c
Water content mg/kg u 300 ASTM D 4019
d
% (m/m) 2,0 % to 2,5 % ISO 6964
Carbon black content
d
grade u 3 ISO 18553
Carbon black dispersion
e
grade u 3 ISO 18553
Pigment dispersion
Resistance to gas h W 20 80 °C, 2 MPa ISO 4437:1997, annex B
constituents
Resistance to rapid crack
f
propagation (RCP):
Full-scale (FS) test: MPa The critical pressure in the FS test shall be 0 °C ISO 13478
d > 250 mm greater than or equal to the value of the
n
MOP of the system multiplied by 1,5
or
g
S4 test MPa The critical pressure in the S4 test shall be 0 °C ISO 13477
greater than or equal to the value of the
MOP of the system divided by 2,4, minus
h
0,72 (expressed in bars)
i
Resistance to slow crack h 165 80 °C, 8,0 bar ISO 13479
f
growth, e > 5 mm
n
j
80 °C, 9,2 bar
a
Non-black compounds shall conform to the weathering requirements of ISO 4437.
b
Test may be carried out at 210 °C provided that there is a clear correlation with the results at 200 °C. In cases of dispute the reference
temperature shall be 200 °C.
c
Only applicable if the compound does not conform to the requirement for volatile-matter content. In cases of dispute, the requirement
for water content shall apply.
d
For black compounds only.
e
Pigment dispersion method for non-black compounds only.
f
Only applicable to material in pipe form.
g
Shall be performed on pipe with a wall thickness W 15 mm.
h
If this requirement is not met, then retesting using the full-scale (FS) test shall be performed (the calculation formula is still under study).
i
Test parameters for PE 80, SDR 11.
j
Test parameters for PE 100, SDR 11.
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ISO 8085-3:2001(E)
5.5 Classification
PE compounds shall be classified by MRS as specified in Table 2.
Table 2 — Classification of PE compounds
s (20 °C, 50 years, 97,5 %)
MRS
lcl
Designation
MPa
MPa
8,00 u s u 9,99
PE 80 8,0
lcl
10,00 u s u 11,19
PE 100 10,0
lcl
The classification shall be established by the producer of the compound using the ISO 9080 extrapolation method
and stated in accordance with ISO 12162.
5.6 Compatibility
Conformity to clause 8 shall be established by the fitting manufacturer to ensure compatibility of the fittings with PE
pipes conforming to ISO 4437. The PE pipe compound(s) used for this demonstration, the fusion condition(s) and
the tooling shall be as detailed in the fitting manufacturer's technical file (see clause 10).
5.7 Materials for non-polyethylene parts
5.7.1 General
All materials shall conform to the relevant International Standards, except where suitable International Standards
do not exist in which case alternative standards may be utilized. In all cases, however, fitness for purpose of the
components shall be established.
All materials used in making the fitting (including rubber, greases and any metal parts which may be used) shall be
as resistant to the external and internal environment as the other elements of the piping system and shall have a
life expectancy, under the following conditions, at least equal to that of the PE piping, conforming to ISO 4437, with
which they are intended to be used:
a) during storage;
b) under exposure to the gas conveyed therein;
c) under exposure to the service environment under the operating conditions.
The requirements for the level of material performance of non-polyethylene parts shall be at least as stringent as
those for the PE compound used for the piping system.
Fitting materials in contact with the PE pipe shall not adversely affect pipe performance or initiate stress cracking.
5.7.2 Metal parts
All parts susceptible to corrosion shall be adequately protected.
When dissimilar metallic materials which may be in contact with moisture are used, steps shall be taken to avoid
galvanic corrosion.
All metal parts shall conform to the relevant International Standards, if such exist, for quality and grade.
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ISO 8085-3:2001(E)
5.7.3 Elastomers
Elastomeric seals shall conform to EN 682.
Other sealing materials intended for gas supply service may be used.
5.7.4 Other materials
Greases and lubricants shall not exude onto fusion areas, and shall not affect the long-term performance of fitting
materials.
Any other material conforming to 5.7.1 may be used, provided that it is established that the fittings containing these
materials conform to this part of ISO 8085.
6 General requirements
6.1 Multiple connections
If a fitting includes one or more spigot ends, these shall conform to the relevant product standard.
6.2 Appearance of the fitting
When viewed without magnification, the internal and external surfaces shall be smooth, clean and free from
scoring, cavities and other surface defects which might prevent conformity to this part of ISO 8085.
6.3 Design
The design of the fitting shall be such that, when the fitting is assembled with a pipe or with another fitting, electrical
coils and/or seals are not displaced.
6.4 Appearance of the joint (factory-made)
When viewed without magnification, the internal and external surfaces of the pipe and fitting after fusion-jointing
shall be free from melt exudation outside the confines of the fitting, apart from that which may be declared
acceptable by the fitting manufacturer.
Any such exudation shall not cause wire movement which could result in short-circuiting when the fitting is jointed
in accordance with the manufacturer’s instructions. There shall be no excessive deformation of the internal
surfaces of the adjoining pipes.
6.5 Electrical characteristics (electrofusion fittings)
The electrical protection provided will depend on the voltage and current used and on the characteristics of the
electrical-power source.
For voltages greater than 25 V, direct human contact with live parts shall not be possible during the fusion-jointing
cycle when jointing is carried out in accordance with the instructions of the fitting manufacturer and assembly
equipment manufacturer.
NOTE During the fusion-jointing process, the fitting is part of an electrical system as defined in IEC 60335-1, IEC 60364-1
and IEC 60449.
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ISO 8085-3:2001(E)
The resistance of the wire at 23 °C shall be as stated by the manufacturer to within the following tolerance limits:
maximum limit: stated value + 10 % + 0,1 W
minimum limit: stated value - 10 %
The 0,1 W added to the maximum limit is to allow for any contact resistance which may exist during measurement.
The protection against direct contact with live parts shall conform to IEC 60529. This protection will depend on
worksite conditions (see ISO/TS 10839).
NOTE See annex A for examples of typical connector sockets.
The surface finish on the connector pins shall ensure minimum contact resistance.
7 Geometrical characteristics
7.1 General
The dimensions of the fittings shall be measured, not less than 24 h after manufacture, in accordance with
ISO 3126, after being conditioned for at least 4 h without any support for re-rounding of the fusion ends.
This part of ISO 8085 concerns only fittings and assemblies and is not concerned with the fusion-jointing
equipment.
The fittings are designated by the nominal diameter of the socket or saddle, which corresponds to the nominal
outside diameter d of the pipe with which they are to be used.
n
7.2 Electrofusion socket fittings
7.2.1 Diameters and lengths of sockets
The depth of penetration L and the minimum length of the fusion zone are given in Table 3. The values of L are
1 1
given for both I- and U-regulation.
In addition to the values given in Table 1, the following requirements apply:
L W 5 mm
3
D W d - 2e
2 n min
where e is the minimum wall thickness specified for corresponding pipe conforming to ISO 4437.
min
Formulae for calculating the equivalent dimensions of non-metric fitting series are given in annex B.
The mean inside diameter of the fitting in the middle of the fusion zone, D , shall not be less than d .
1 n
The manufacturer shall decla
...
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