kSIST FprEN 17415-2:2021

District cooling pipes - Bonded single pipe systems for directly buried cold water networks - Part 2: Factory made fitting assemblies of steel or plastic service pipe, polyurethane thermal insulation and a casing of polyethylene

This document specifies requirements, design and test methods for factory made thermally insulated bonded fitting assemblies for directly buried district cooling distribution systems, comprising a service fitting from DN 15 to DN 1200, rigid polyurethane foam insulation and a casing of polyethylene.
The fitting assembly may also include the following additional elements: measuring wires, spacers and diffusion barriers.
This document covers the following fitting assemblies: bend, tee, reducer, cap, single use compensator and anchor.
This document applies only to insulated fitting assemblies, for continuous operation with water at various
temperatures (1 to 30)°C and a maximum operation pressure of 25 bar. The design is based on an expected service life with continuous operation of a minimum 50 years.

Fernkühlungsrohre - Werkmäßig gedämmte Verbundmantelrohrsysteme für direkt erdverlegte Fernkältenetze - Teil 2: Werkmäßig gedämmte Verbund-Formstücke bestehend aus Stahl-oder Plastik-Mediumrohr, Polyurethan-Wärmedämmung und Außenmantel aus Polyethylen

Fernkälterohre — Einzelrohr-Verbundsysteme für direkt erdverlegte Fernkältenetze — Teil 2: Werkmäßig gefertigte Verbundformstücke, bestehend aus Stahl- oder Kunststoff-Mediumrohr, einer Wärmedämmung aus Polyurethan und einer Ummantelung aus Polyethylen

Réseaux d’eau glacée - Systèmes bloqués de tuyaux pour les réseaux d'eau glacée enterrés directement - Partie 2 : Assemblages de raccords manufacturés pour tubes de service en acier ou en plastique, isolation thermique en polyuréthane et tube de protection en polyéthylène

Le présent document spécifie les exigences, la conception et les méthodes d’essai pour des assemblages manufacturés de raccords bloqués préisolés thermiquement pour les réseaux de distribution d’eau glacée urbains enterrés directement, constitués d’un raccord de DN 15 à DN 1200, d’une isolation en mousse de polyuréthane rigide et d’un tube de protection en polyéthylène.
Le raccord préisolé peut également comprendre les éléments supplémentaires suivants : des câbles de mesure, des entretoises et les barrières anti diffusion.
Le présent document couvre les raccords préisolés suivants : coude, té, réducteur, bouchon, compensateur à usage unique et pièce d’ancrage.
Le présent document ne concerne que les assemblages de raccords préisolés, destinés à un usage continu avec de l’eau à diverses températures (de 1 °C à 30 °C) et à une pression de service maximale de 25 bar.
La conception est fondée sur une durée utile prévue en fonctionnement continu d’au moins 50 ans

Cevi za daljinsko hlajenje - Spojeni enocevni sistemi za neposredno vkopana hladnovodna omrežja - 2. del: Tovarniško izdelana armatura iz jeklene ali plastične delovne cevi, poliuretanske toplotne izolacije in polietilenskega plašča

General Information

• Status: Not Published
• Public Enquiry End Date: 30-Sep-2020
• ICS: 23.040.99 - Other pipeline components
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 09-Sep-2021
• Due Date: 14-Nov-2021
• Ref Project: EN 17415-2:2021 - District cooling pipes - Bonded single pipe systems for directly buried cold water networks - Part 2: Factory made fitting assemblies of steel or plastic service pipe, polyurethane thermal insulation and a casing of polyethylene

Standards Content (sample)

SLOVENSKI STANDARD
oSIST prEN 17415-2:2020
01-september-2020
Cevi za daljinsko hlajenje - Spojeni enocevni sistemi za neposredno vkopana
hladnovodna omrežja - 2. del: Tovarniško izdelan cevni sestav iz jeklene ali

plastične delovne cevi, poliuretanske toplotne izolacije in polietilenskega plašča

District cooling pipes - Bonded single pipe systems for directly buried cold water

networks - Part 2: Factory made fitting assemblies of steel or plastic service pipe,

polyurethane thermal insulation and a casing of polyethylene
Fernkühlungsrohre - Werkmäßig gedämmte Verbundmantelrohrsysteme für direkt
erdverlegte Fernkältenetze - Teil 2: Werkmäßig gedämmte Verbund-Formstücke
bestehend aus Stahl-oder Plastik-Mediumrohr, Polyurethan-Wärmedämmung und
Außenmantel aus Polyethylen
Réseaux d’eau glacée - Systèmes bloqués de tuyaux pour les réseaux d'eau glacée

enterrés directement - Partie 2 : Assemblages de raccords manufacturés pour tubes de

service en acier ou en plastique, isolation thermique en polyuréthane et tube de
protection en polyéthylène
Ta slovenski standard je istoveten z: prEN 17415-2
ICS:
23.040.99 Drugi sestavni deli za Other pipeline components
cevovode
oSIST prEN 17415-2:2020 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
oSIST prEN 17415-2:2020
---------------------- Page: 2 ----------------------
oSIST prEN 17415-2:2020
DRAFT
EUROPEAN STANDARD
prEN 17415-2
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2020
ICS 23.040.99
English Version
District cooling pipes - Bonded single pipe systems for
directly buried cold water networks - Part 2: Factory made
fitting assemblies of steel or plastic service pipe,
polyurethane thermal insulation and a casing of
polyethylene

Réseaux d'eau glacée - Systèmes bloqués de tuyaux Fernkühlungsrohre - Werkmäßig gedämmte

pour les réseaux d'eau glacée enterrés directement - Verbundmantelrohrsysteme für direkt erdverlegte

Partie 2 : Assemblages de raccords manufacturés pour Fernkältenetze - Teil 2: Werkmäßig gedämmte

tubes de service en acier ou en plastique, isolation Verbund-Formstücke bestehend aus Stahl-oder Plastik-

thermique en polyuréthane et tube de protection en Mediumrohr, Polyurethan-Wärmedämmung und

polyéthylène Außenmantel aus Polyethylen

This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee

CEN/TC 107.

If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations

which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other

language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC

Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,

Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,

Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and

United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are

aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without

notice and shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels

© 2020 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 17415-2:2020 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

Introduction .................................................................................................................................................................... 4

1 Scope .................................................................................................................................................................... 5

2 Normative references .................................................................................................................................... 5

3 Terms and definitions ................................................................................................................................... 7

4 Requirements ................................................................................................................................................... 7

4.1 General requirements ................................................................................................................................... 7

4.2 Service pipe parts ............................................................................................................................................ 7

4.3 Casing ............................................................................................................................................................... 15

4.4 Polyurethane (PUR) foam thermal insulation ................................................................................... 15

4.5 Fitting assemblies ........................................................................................................................................ 15

4.6 Surveillance system ..................................................................................................................................... 19

5 Test methods ................................................................................................................................................. 19

5.1 General ............................................................................................................................................................. 19

5.2 Test specimens .............................................................................................................................................. 19

5.3 Steel service pipe parts .............................................................................................................................. 20

5.4 Plastics service pipe fittings ..................................................................................................................... 21

5.5 Casing ............................................................................................................................................................... 21

5.6 Polyurethane (PUR) foam thermal insulation ................................................................................... 21

5.7 Fitting assemblies ........................................................................................................................................ 21

5.8 Surveillance system ..................................................................................................................................... 22

6 Marking ............................................................................................................................................................ 22

6.1 General ............................................................................................................................................................. 22

6.2 Service pipe .................................................................................................................................................... 23

6.3 Casing ............................................................................................................................................................... 23

6.4 Fitting assembly ............................................................................................................................................ 23

6.5 Single use compensators ........................................................................................................................... 24

Annex A (informative) Guidelines for inspection and testing ................................................................... 25

Annex B (informative) Procedures for casing welding ................................................................................ 29

Annex C (informative) Waste treatment and recycling ............................................................................... 33

Bibliography ................................................................................................................................................................. 34

---------------------- Page: 4 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
European foreword

This document (prEN 17415-2:2020) has been prepared by Technical Committee CEN/TC 107

“Prefabricated district heating and district cooling pipe system”, the secretariat of which is held by DS.

This document is currently submitted to the CEN Enquiry.
---------------------- Page: 5 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
Introduction

Factory made bonded single pipe systems for directly buried district cooling networks are of common

technical usage. In order to ensure quality including product-related service life, to assure safety in use,

economical energy usage and to facilitate comparability in the market, CEN/TC 107 decided to set up

standards for these products.

This document is one of a series of standards which form several parts of EN 17415, District cooling pipes –

Bonded single pipe systems for directly buried cold water networks:

— Part 1: Factory made pipe assembly of steel or plastic service pipe, polyurethane thermal insulation and a

casing of polyethylene (this document) ;

— Part 2: Factory made fitting assemblies of steel or plastic service pipe, polyurethane thermal insulation and

a casing of polyethylene ;

— Part 3: Factory made steel valve assembly for steel or plastic service pipe, polyurethane thermal insulation

and a casing of polyethylene ;
The other standards from CEN/TC 107 covering this subject are:

— EN 17414-1, District cooling pipes – Factory made flexible pipe systems – Part 1: Classification, general

requirements and test methods ;

— EN 17414-2, District cooling pipes – Factory made flexible pipe systems – Part 2: Bonded system with

plastic service pipes; requirements and test methods ;

— EN 17414-3, District cooling pipes – Factory made flexible pipe systems – Part 3: Non bonded system with

plastic service pipes; requirements and test methods ;

— EN ZZZZZ-1, District cooling pipes – Design and installation of thermal insulated bonded single and twin

pipe systems for directly buried cold water networks – Part 1: Design ;

— EN ZZZZZ-2, District cooling pipes – Design and installation of thermal insulated bonded single and twin

pipe systems for directly buried cold water networks – Part 2: Installation ;

— EN 489-1, District heating pipes – Bonded single and twin pipe systems for buried hot water networks –

Part 1: Joint casing assemblies and thermal insulation for hot water networks in accordance with

EN 13941-1;

— EN 14419, District heating pipes – Bonded single and twin pipe systems for directly buried hot water

networks – Surveillance systems;
1) Under development.
---------------------- Page: 6 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
1 Scope

This document specifies requirements, design and test methods for factory made thermally insulated

bonded fitting assemblies for directly buried district cooling distribution systems, comprising a service

fitting from DN 15 to DN 1200, rigid polyurethane foam insulation and a casing of polyethylene.

The fitting assembly can also include the following additional elements: measuring wires, spacers and

diffusion barriers.

This document covers the following fitting assemblies: bend, tee, reducer, cap, single use compensator and

anchor.

This document applies only to insulated fitting assemblies, for continuous operation with water at various

temperatures (1 to 30) °C and a maximum operation pressure of 25 bar.

The design is based on an expected service life with continuous operation of a minimum 50 years.

2 Normative references

The following documents are referred to in the text in such a way that some or all of their content constitutes

requirements of this document. For dated references, only the edition cited applies. For undated references,

the latest edition of the referenced document (including any amendments) applies.

EN 10204, Metallic products — Types of inspection documents

EN 10253-2, Butt-welding pipe fittings — Part 2: Non alloy and ferritic alloy steels with specific inspection

requirements

EN 12201-2, Plastics piping systems for water supply, and for drainage and sewerage under pressure –

Polyethylene (PE) – Part 2: Pipes

EN 12201-3, Plastics piping systems for water supply, and for drainage and sewerage under pressure –

Polyethylene (PE) – Part 3: Fittings

EN 12201-5, Plastics piping systems for water supply, and for drainage and sewerage under pressure –

Polyethylene (PE) – Part 5: Fitness for purpose of the system

EN 12814-1, Testing of welded joints of thermoplastics semi-finished products — Part 1: Bend test

EN 13018, Non-destructive testing —Visual testing — General principles

EN 13067, Plastics welding personnel – Qualification testing of welders – Thermoplastics welded assemblies

EN 14419, District heating pipes – Bonded single and twin pipe systems for directly buried hot water networks

– Surveillance systems

EN 14870-1, Petroleum and natural gas industries — Induction bends, fittings and flanges for pipeline

transportation systems — Part 1: Induction bends (ISO 15590-1:2009 modified)

EN 17415-1:2020, District cooling pipes — Bonded single pipe systems for directly buried cold water

networks — Part 1: Factory made pipe assembly of steel or plastic service pipe, polyurethane thermal insulation

and a casing of polyethylene
2) Under development.
---------------------- Page: 7 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)

EN 13941-1, District heating pipes - Design and installation of thermal insulated bonded single and twin pipe

systems for directly buried hot water networks - Part 1: Design

EN 13941-2, District heating pipes - Design and installation of thermal insulated bonded single and twin pipe

systems for directly buried hot water networks - Part 2: Installation

EN ISO 3452-1, Non-destructive testing — Penetrant testing — Part 1: General principles (ISO 3452-1)

EN ISO 5579, Non-destructive testing — Radiographic testing of metallic materials using film and X- or gamma

rays - Basic rules (ISO 5579)

EN ISO 5817, Welding — Fusion-welded joints in steel, nickel, titanium and their alloys (beam welding

excluded) — Quality levels for imperfections (ISO 5817)

EN ISO 8501-1, Preparation of steel substrates before application of paints and related products — Visual

assessment of surface cleanliness — Part 1: Rust grades and preparation grades of uncoated steel substrates

and of steel substrates after overall removal of previous coatings (ISO 8501-1)

EN ISO 9606-1, Qualification testing of welders — Fusion welding — Part 1: Steels (ISO 9606-1)

EN ISO 9692-1:2013, Welding and allied processes — Types of joint preparation — Part 1: Manual metal arc

welding, gas-shielded metal arc welding, gas welding, TIG welding and beam welding of steels

(ISO 9692-1:2013)

EN ISO 9934-1, Non-destructive testing — Magnetic particle testing — Part 1: General principles (ISO 9934-1)

EN ISO 10675-1, Non-destructive testing of welds — Acceptance levels for radiographic testing — Part 1: Steel,

nickel, titanium and their alloys (ISO 10675-1)

EN ISO 11666, Non-destructive testing of welds — Ultrasonic testing — Acceptance levels (ISO 11666)

EN ISO 13760, Plastics pipes for the conveyance of fluids under pressure – Miner’s rule – Calculation method for

cumulative damage (ISO 13760)

EN ISO 14732, Welding personnel — Qualification testing of welding operators and weld setters for

mechanized and automatic welding of metallic materials (ISO 14732)

EN ISO 15607, Specification and qualification of welding procedures for metallic materials — General rules

(ISO 15607)

EN ISO 16810, Non-destructive testing — Ultrasonic testing — General principles (ISO 16810)

EN ISO 17636-1, Non-destructive testing of welds — Radiographic testing — Part 1: X- and gamma-ray

techniques with film (ISO 17636-1)

EN ISO 17636-2, Non-destructive testing of welds — Radiographic testing — Part 2: X- and gamma-ray

techniques with digital detectors (ISO 17636-2)

EN ISO 17637, Non-destructive testing of welds — Visual testing of fusion-welded joints (ISO 17637)

EN ISO 17638, Non-destructive testing of welds — Magnetic particle testing (ISO 17638)

Under development.
---------------------- Page: 8 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)

EN ISO 17640, Non-destructive testing of welds — Ultrasonic testing — Techniques, testing levels, and

assessment (ISO 17640)

EN ISO 23277, Non-destructive testing of welds — Penetrant testing — Acceptance levels (ISO 23277)

EN ISO 23278, Non-destructive testing of welds — Magnetic particle testing — Acceptance levels (ISO 23278)

3 Terms and definitions

For the purposes of this document the terms and definitions given in EN 17415-1 apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
4 Requirements
4.1 General requirements

Unless otherwise specified, the requirements shall be valid for each single measurement.

For information on suitable guidelines for inspection of factory made fitting assemblies, see Annex A.

4.2 Service pipe parts
4.2.1 Steel service pipe parts
4.2.1.1 General

The material of the fitting steel parts shall be certified in accordance with EN 10204. If traceability on

material is required by the end user it shall be specified at the time of ordering. Corresponding material

certificates shall be delivered to the end user if specified at the time of ordering.

4.2.1.2 Specification

The fitting steel material shall be in accordance with the steel grade specification in EN 17415-1.

All steel pipes and components used for manufacturing of pipe assemblies under the scope of this document

shall as a minimum be delivered to the manufacturer with an inspection certificate 3.1 according to

EN 10204. The inspection certificate shall on request be passed on to the client who orders the fitting

assemblies.

In case a material related inspection certificate 3.1 according to EN 10204 is required by the client who

orders the fitting assemblies, this request shall be given whilst placing the order with the manufacturer of

the fitting assemblies.

Any later request for provision of such documentation could be too late and possibly can't be met by the

manufacturer, since the manufacturer has to organize the assignment of 3.1 certificates to pipes and part of

pipes before starting the production.
4.2.1.3 Wall thickness and diameter

According to the scope of this document, all components shall be designed for a minimum operating

pressure of 16 bar.

If the fitting assemblies are intended to be used in situations with pressures higher than 16 bar, extra

calculations will be necessary.
---------------------- Page: 9 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)

The minimum nominal wall thickness of all components shall prior to processing be at least the same as for

the service pipes in accordance with EN 17415-1.

The nominal diameter, the outside diameter, the tolerances on the diameter of the pipe ends and the wall

thickness shall be the same as for the service pipes in accordance with EN 17415-1.

Subject to design considerations other wall thicknesses than those given in EN 17415-1 may be used, but in

no case shall these be less than the minima indicated in EN 17415-1.

All components shall be designed in accordance with EN 13941-1 for the actions and stresses that

normally occur during the service life of the fitting assembly (or of the component).

4.2.1.4 Bends
4.2.1.4.1 Butt welding bends

The dimensions shall be in accordance with EN 10253-2 with the exception that the bend radius shall

be ≥ 1,5 times the outer diameter.
4.2.1.4.2 Cold formed bends

Cold formed bends shall be produced from seamless pipe or longitudinal welded pipes. At cold formed bends

made of longitudinal welded pipes the weld bead shall be welded to factor V = 1 (calculation stress = 100 %).

After bending, the minimum wall thickness of the bent pipe shall be not less than 85 % of the wall thickness

of the straight pipe (see EN 17415-1).
The maximum ovality in the bent area shall not exceed 6 %.
The formula for the calculation of the ovality is:
D − D
( )
s max s min
o ×100 (1)
where
o is the ovality, in %;
D is the maximum outside diameter;
s max
D is the minimum outside diameter in the same cross section in the bended
s min
area;
D is the specified outside diameter.

There shall be no folding in the bent area. Waves may be accepted, when the maximum height between

trough and crest of the wave does not exceed 25 % of the nominal wall thickness of the bent pipe.

4.2.1.4.3 Hot-formed bends

For hot-formed bends manufactured from straight pipes by means of inductive heating (induction bends), no

heat treatment is necessary as far as this method is applied with unalloyed or low-alloyed steel with

[Mo] < 0,65 %. Hot-formed bends shall be supplied in conformity with EN 14870-1.

If for the bending other heating methods are applied, heat treatment following the bending of the pipes is

required.
Under development.
---------------------- Page: 10 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)

If a hot-formed bend has to be made from line pipe, this shall be specified to the pipe manufacturer at the

time of ordering so that the pipe manufacturer can take this into account when selecting the (chemical)

composition of the pipe material and the welding filler material.

It is recommended to determine per batch, diameter, wall thickness and bend radius, through mechanical

testing, that the bends comply with the applicable material specifications. It is customary that a

representative bend or an (additional) section of a bend of adequate length will be manufactured during the

production process and that 10 % of the bends will be tested.
4.2.1.4.4 Tolerances of bending angles

The deviation from the nominal bending angle shall not exceed the tolerances given in Table 1.

Table 1 — Deviations from nominal bending angle
Nominal diameter of Deviation
service pipe
≤ DN 200 ±2,0°
> DN 200 ±1,0°
4.2.1.5 T-pieces
4.2.1.5.1 Forged T-pieces

The wall thickness t and t (see EN 10253-2) shall be at least the same as those for the straight pipes (see

EN 17415-1). All other dimensions shall be in accordance with EN 10253-2.
4.2.1.5.2 Welded T-pieces

Welded T-pieces shall be manufactured by drawing a collar on which the branch pipe is welded or by

welding the branch pipe directly to the main pipe. The wall thickness of the collar shall be at least the same

as that for the branch pipe (see EN 17415-1). The collar shall be drawn opposite the welding seam in the

main pipe. When using branch pipe directly welded to the main pipe, compensating (reinforcement) plates

may be used according to EN 13941-1 requirements.
4.2.1.5.3 Tolerances of angles between branch pipes and main pipes

The branch pipes shall be perpendicular to the main pipes within a tolerance of ± 2,0°.

4.2.1.6 Reducers

Reducers shall be in accordance with EN 10253-2, except for the wall thicknesses t and t (see EN 10253-2)

which shall be at least the same as for the straight pipes (see EN 17415-1) to be welded to the fittings.

4.2.1.7 Anchors

The anchors shall be marked with the information concerning maximum loads for which the construction

was designed and calculated. The lifetime of the system shall not be influenced by the anchors construction.

4.2.1.8 Single use compensators
A single use compensator shall comply with the requirements of EN 13941-1 .
4.2.1.9 Caps

Caps (dished ends) shall be in accordance with EN 10253-2 and comply with the requirements of EN 13941-

1 .
Under development.
---------------------- Page: 11 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
4.2.1.10 Fusion welding of steel fittings
4.2.1.10.1 Filler material

Filler material shall after welding have mechanical characteristics comparable with the parent metal.

4.2.1.10.2 Welding process

All types of fusion welding are acceptable but arc welding with covered electrodes and gas-shielded metal-

arc welding are preferred. The welding process shall be specified and approved in accordance with

EN ISO 15607.
The method of approval may be chosen by the manufacturer.
Fittings of wall thickness ≥ 5,6 mm shall be welded in more than one pass.
4.2.1.10.3 Preparation for welding

Pipe ends shall be prepared in accordance with the welding procedure used. When using covered electrodes

or gas-shielded metal-arc welding, pipe ends and fittings with equal wall thickness shall be prepared in

accordance with EN ISO 9692-1.

Table 2 of this document is derived from EN ISO 9692-1:2013, Table 1 and gives the relation between wall

thickness and reference number.

Table 2 — Preparation of ends of pipes and fittings for weldings according to EN ISO 9692-1:2013

Symbol Type of preparation Wall thickness t of steel service Reference to
pipe fittings or fitting end EN ISO 9692-1:2013, Table 1
II Square preparation t < 3 mm 1.2.1
V Single V preparation 3 mm ≤ t ≤ 10 mm 1.3
Y Single Y preparation with t > 10 mm 1.5
broad root face
NOTE Symbols are in accordance with EN ISO 2553.

Pipe ends and fittings with different wall thicknesses shall be prepared and adapted for misalignment in

accordance with Table 3 and Figure 1 of this document.
Table 3 — Adaptation of misalignment and difference in wall thickness
Adaptation Required action
Misalignment
Misalignment h ≤ 0,3 t, max. 1 mm Figure 1 detail A
Misalignment 1 mm < h ≤ 10 mm Adaptation of pipe ends
Misalignment h > 10 mm Extra fitting Extra prepared steel fitting minimum
length.
The seam spacing shall be such that the
heat-affected zones do not overlap or
interact. A spacing of 100 mm or more is
recommended. The minimum spacing is
50 mm.
Difference in wall thickness

Differences in wall thickness: t' ≤ 1,5 tn Figure 1 detail B Adaptation of thicker wall t'

Differences in wall thickness: t' > 1,5 tn Figure 1 detail C Adaptation of both sides

---------------------- Page: 12 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
Key
h misalignment
tn smallest wall thickness
t’ largest wall thickness

Figure 1 — Misalignment, difference in wall thickness and steel service pipe end preparation, in

accordance with EN 13941-2

When manufacturing T-pieces with the branch pipe welded directly to the main pipe, preparations shall

comply with Figure 2.
Under development.
---------------------- Page: 13 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-2:2020 (E)
Key

a Section X at crotch of right angle branch c Section Y at flank of unequal branch. Ratios of

b Section Y at flank of unequal branch. Ratios of diameters > 2/3
diameters ≤ 2/3 d Section W at flank of equal branch
Figure 2 — Preparation of set-on branches
4.2.1.10.4 Inspection of welds

When visual surface examination is carried out, it shall be in accordance with 5.3.1. The examinations

include a check of surface, internal, joint geometry and multiple imperfections. The welding shall comply

with “quality level B” of EN ISO 5817.

When a leak-tightness test is carried out in accordance with 5.3.2 or 5.3.3, the welds shall fulfil the

conditions stated there.

When non-destructive test is carried out, it shall be in accordance with 5.3.4. The weld shall comply with

“quality level B” of EN ISO 5817.
4.2.1.10.5 Competence of the welder

The welder shall have a valid certificate according to EN ISO 9606-1 for the techniques, material groups,

dimension ranges and welding position concerned. Welding personnel operating mechanized welding

equipment shall be qualified in accordance with EN ISO 14732.
---------------------- Page: 14 ----------------------
oSIST prEN 17415-2:2020
prEN 17415-
...