SIST EN 14628:2006

SLOVENSKI STANDARD
SIST EN 14628:2006
01-marec-2006
Litoželezne cevi, fazonski kosi in pribor – Zunanji polietilenski premaz cevi za zelo
agresivna tla – Zahteve in preskusne metode
Ductile iron pipes, fittings and accessories - External polyethylene coating for pipes -
Requirements and test methods
Rohre, Formstücke und Zubehörteile aus duktilem Gusseisen - Polyethylenumhüllung
von Rohren - Anforderungen und Prüfverfahren
Tuyaux, raccords et accessoires en fonte ductile - Revetement extérieur en polyéthylene
pour tuyaux - Exigences et méthodes d'essai
Ta slovenski standard je istoveten z: EN 14628:2005
ICS:
23.040.10 Železne in jeklene cevi Iron and steel pipes
23.040.40 Kovinski fitingi Metal fittings
25.220.01 Površinska obdelava in Surface treatment and
prevleke na splošno coating in general
SIST EN 14628:2006 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 14628:2006

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SIST EN 14628:2006
EUROPEAN STANDARD
EN 14628
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2005
ICS 23.040.10; 23.040.40

English Version
Ductile iron pipes, fittings and accessories - External
polyethylene coating for pipes - Requirements and test methods
Tuyaux, raccords et accessoires en fonte ductile - Rohre, Formstücke und Zubehör aus duktilem Gusseisen -
Revêtement extérieur en polyéthylène de tuyaux - Polyethylenumhüllung von Rohren - Anforderungen und
Exigences et méthodes d'essai Prüfverfahren
This European Standard was approved by CEN on 29 August 2005.
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. Up-to-date lists and bibliographical references concerning such national
standards may be obtained on application to the Central Secretariat or to any CEN member.
This European Standard exists 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 Central Secretariat has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2005 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14628:2005: E
worldwide for CEN national Members.

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SIST EN 14628:2006
EN 14628:2005 (E)
Contents Page
Foreword .3
Introduction.4
1 Scope .5
2 Normative references .5
3 Terms and definitions.5
4 Ordering information .7
5 Technical Requirements.7
6 Performance requirements.9
7 Test Methods.11
Annex A (informative) Quality assurance .16
Annex B (informative) Application process.19
Annex C (informative) Coating material.21
Bibliography.23

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SIST EN 14628:2006
EN 14628:2005 (E)
Foreword
This European Standard (EN 14628:2005) has been prepared by Technical Committee CEN/TC 203 “Cast iron
pipes, fittings and their joints”, the secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an identical text or
by endorsement, at the latest by April 2006, and conflicting national standards shall be withdrawn at the latest by
April 2006.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark,
Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
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SIST EN 14628:2006
EN 14628:2005 (E)
Introduction
This European Standard is in conformity with the general requirements already established by CEN/TC 164 in the
field of water supply (e.g. potable water) and CEN/TC 165 in the field of waste water.
In respect of potential adverse effects on the quality of water intended for human consumption, caused by the
product covered by this standard:
a) this European Standard provides no information as to whether the product may be used without restriction in
any of the member states of the EU or EFTA;
b) it should be noted that, while awaiting the adoption of verifiable European criteria, existing national regulations
concerning the use and/or the characteristics of this product remain in force.
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SIST EN 14628:2006
EN 14628:2005 (E)
1 Scope
This European Standard defines the requirements and test methods applicable to factory applied extruded
polyethylene coatings for the external corrosion protection of ductile iron pipes conforming to EN 545, EN 598 and
EN 969 for use at operating temperatures up to 50 °C.
This European Standard does not cover ductile iron pipes protected with thin PE sleeve. Special works at site like
drilling, tapping etc. may influence the corrosion protection properties. Those job steps shall be included in the
instructions of pipe saddle and accessory manufacturers and all other essential installation instructions. These
instructions are not part of this European Standard.
2 Normative references
The following referenced documents are indispensable for the application 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 545, Ductile iron pipes, fittings, accessories and their joints for water pipelines – Requirements and test
methods.
EN 598, Ductile iron pipes, fittings, accessories and their joints for sewerage application – Requirements and test
methods.
EN 969, Ductile iron pipes, fittings, accessories and their joints for gas pipelines – Requirements and test methods.
EN 1238, Adhesives – Determination of the softening point of thermoplastic adhesives (ring and ball).
EN ISO 527-1, Plastics – Determination of tensile properties - Part 1: General principles (ISO 527-1:1993 including
Corr 1:1994).
EN ISO 527-2, Plastics – Determination of tensile properties - Part 2: Test conditions for moulding and extrusion
plastics (ISO 527-2:1993 including Corr 1:1994).
EN ISO 1133, Plastics – Determination of the melt mass - flow rate (MFR) and the melt volume - flow rate (MVR) of
thermoplastics (ISO 1133:1997).
EN ISO 3681, Binders for paints and varnishes – Determination of saponification value – Titrimetric method (ISO
3681:1996).
EN ISO 4892-2, Plastics – Methods of exposure to laboratory light sources – Part 2: Xenon-arc sources (ISO 4892-
2:1994).
3 Terms and definitions
For the purposes of this European Standard, the following terms and definitions apply.
3.1
ductile iron
cast iron used for pipes, fittings and accessories in which graphite is present substantially in spheroidal form
3.2
elongation at break
relative change in length of the specimen of the polyethylene material when it breaks in a tensile test
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SIST EN 14628:2006
EN 14628:2005 (E)
3.3
heat ageing
artificial ageing of the polyethylene under the effects of hot air at a given temperature and over a given period
3.4
impact strength
impact energy which a coating can withstand without damage under defined test conditions
3.5
indentation resistance
resistance of the coating to the penetration of a punch under defined test conditions
3.6
light ageing
artificial ageing of the polyethylene under the effects of xenon arc radiation at an elevated temperature and at a
given level of atmospheric humidity using a xenon test apparatus
3.7
minimum coating thickness
lower limit specified for the polyethylene coating thickness
3.8
non-porosity
absence of holidays in a high voltage test under defined test conditions
3.9
peel resistance
force required to peel off a strip of polyethylene coating over a defined peeling path under defined test conditions
3.10
polyethylene coating
coating which generally consists of two factory applied layers:
 an adhesive layer applied by extrusion or by hot spraying; and
 an extruded polyethylene compound outer layer applied either by the tubular extrusion method (cross head
extrusion) or by the flat die wrapping extrusion method.
3.11
specific coating resistance
surface related electric resistance of the coating perpendicular to the pipe wall
3.12
performance test
test which is done once and is repeated only after change of polymer supplier, polymer material or relevant change
in process application
3.13
routine test
test carried out to control the manufacturing process with a frequency defined by the manufacturer
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EN 14628:2005 (E)
4 Ordering information
4.1 General The following information shall be supplied to the manufacturer by the purchaser:
4.2 Mandatory
Ductile iron pipes according to EN 545, EN 598 or EN 969, but coated in accordance with this European Standard
shall be specified in the purchasers enquiry and order by reference to this standard:
EXAMPLE 5 000 m of ductile iron pipe DN 300 according to EN 545;
external polyethylene coating according to EN 14628.
4.3 Options to be indicated by the purchaser
One of the following options shall be specified by the purchaser:
a) standard thickness, pipe not zinc-coated: PE-A;
b) increased thickness, pipe not zinc-coated: PE-B;
c) standard thickness, pipe zinc-coated: PE-C;
d) increased thickness, pipe zinc-coated: PE-D.
In the event that no option is stipulated option a) shall apply.
5 Technical Requirements
5.1 Surface preparation
The polyethylene coating shall be applied to the works' standard oxide skin surface, blast cleaned surface or zinc
coated surface of ductile iron pipes. Immediately prior to application the surface of the pipes shall be substantially
free of rust (individual incipient rust spots are permissible), loose constituent materials, dirt, oil, grease and
moisture.
5.2 Material properties
5.2.1 Polyethylene
Only the use of virgin material is permitted.
5.2.2 Adhesive
The adhesive consists generally of a blend of rubber and high molecular weight resins and its physical properties
shall conform to the values specified in Table 1.
Table 1 — Adhesive physical properties
Property Standard Requirements
Softening point EN 1238 70 °C to 112 °C
Saponification value EN ISO 3681 < 3 mg KOH/g
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EN 14628:2005 (E)
5.3 Finished polyethylene coating
5.3.1 Appearance and continuity
The polyethylene coating shall be of:
 uniform colour, except for permitted marking;
 uniform appearance and smoothness, except admissible repairs.
5.3.2 Minimum coating thickness
The minimum coating thickness shall comply with the values given in Table 2 for the standard thickness or for the
increased thickness (see 4.2.).
Table 2 — Polyethylene thickness
Minimum coating thickness mm
Nominal size
Increased
DN
Standard thickness
thickness
80 to 100 1,8 2,5
125 to 250 2,0 2,5
300 to 450 2,2 3,0
500 to 700 2,5 3,5
800 to 1 400 3,0 3,5
1 500 to 2 000 3,5 4,0
The polyethylene coating thickness shall be measured in accordance with the method defined in 7.2.
Localised areas where the minimum coating thickness is not attained are permissible if these do not exceed a total
2
area of 5 cm over one metre length of pipe and the thickness of the coating is not less than 90 % of the specified
minimum coating thickness.
5.3.3 Ends of pipes
The spigot shall be not covered by the polyethylene coating over a free length “a” (see Figure 1).

Key
1 Push in socket
Figure 1 — Ends of pipe
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EN 14628:2005 (E)
The uncoated spigot length “a” depends on the type of joint. It is the responsibility of the manufacturer to define the
appropriate uncoated length for each type of joint.
The front end of sockets may be uncoated on a length “b” depending on the application method (see Annex B):
 tubular extrusion: < 5 mm, (15 mm after storage outside);
 flat die wrapping extrusion: < 50 mm.
The pipe ends surfaces not covered by the polyethylene coating (spigot, front end of socket and internal section of
socket) shall be coated with filled bituminous paint or other suitable coating(s). Where such coatings are in contact
with water intended for human consumption, these shall comply with the relevant requirements stated in the
introduction of this European Standard.
NOTE The pipe parts not covered by PE will be protected after laying using appropriate measures, e.g. heat shrinkable
sleeves, which are in compliance with EN 545, EN 598 or EN 969.
5.4 Repairs
In case of holidays or damage, repairs shall be carried out in accordance with the manufacturer’s written
instructions. All repairs shall subsequently meet the non-porosity test requirements.
5.5 Marking
All pipes shall be marked legibly and durably according to the pipe standard EN 545, EN 598 or EN 969 with the
addition: PE-A, PE-B, PE-C or PE-D (see 4.3). The transported medium can be denoted by appropriate markings,
e.g. by coextruded coloured stripes.
5.6 Peeling strength
Experience with the transport, laying and operation of polyethylene-coated pipes and pipelines has shown that
good bonding is necessary in order to avoid mechanical damage. It is, however, not necessary to ensure the
corrosion protection properties of polyethylene coating if the thickness and the quality of the coating comply with
the requirements of this European Standard.
When tested in accordance with method 1 as defined in 7.1.2, the adhesive shall be selected in order to provide a
mean peel resistance of at least 10 N per cm strip width (zinc coating) or 20 N per cm strip width (oxide skin) of
polyethylene coating.
When tested in accordance with method 2 defined in 7.1.3, the peeling time shall be at least 0,04. DN in minutes.
The mean peeling rate is thus 10 mm/min.
5.7 Non-porosity
The polyethylene coating shall be free from pores extending through the coating, so, no electrical puncture shall
occur according to the test method defined in 7.3.
6 Performance requirements
6.1 Impact strength
The minimum impact strength shall be determined in accordance with the test method defined in 7.4.
The number of electrical punctures in the test shall be confined to range A as defined in Figure 2.
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Key
X Number of punctures
Y Number of impacts
A Range A Test passed
B Test to be continued
C Test failed
Figure 2 — Test ranges of impact resistance
6.2 Indentation resistance
The indentation resistance shall be assessed by testing in accordance with the test method defined in 7.5.
The indentation depth of the polyethylene coating shall not exceed 0,3 mm.
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EN 14628:2005 (E)
6.3 Elongation at break
The elongation at break shall be assessed by testing in accordance with the test method defined in 7.6.
The elongation at break for polyethylene coating shall be at least 200 %.
Ten specimens taken from at least five different pipes shall be subjected to this test.
The maximum allowable failure rate shall be one specimen out of ten. If the result does not comply with the
requirements, a second test with ten specimens shall be carried out without any failure allowed.
6.4 Specific coating resistance
The specific coating resistance of the polyethylene coating shall be assessed by testing in accordance with the test
method defined in 7.7.
The specific coating resistance of the polyethylene coating after immersion in a 0,1 M NaCl solution for 100 days
8 2
shall be at least 10 Ω m .
The ratio (resistance after 100 days)/(resistance after 70 days) shall not be less than 0,8 if the surface resistance of
the coating is only one decimal power above the minimum permissible value for 100 days.
6.5 Heat ageing
The heat ageing shall be assessed in accordance with the test method defined in 7.8.
The change in the melt-flow rate of the specimens after being subjected to the effects of heat shall not
exceed ± 35 % of the initial value.
6.6 Light ageing
The light ageing shall be assessed in accordance with the test method defined in 7.9.
The change in the melt-flow rate of the specimens after exposure to xenon arc radiation shall not exceed ± 35 % of
the initial value.
7 Test Methods
7.1 Peel resistance of the adhesive
7.1.1 General
Test methods 1 and 2 are comparative tests to assess the resistance to peeling of the polyethylene coating on
ductile iron pipes. They do not provide absolute bonding strength values. Therefore, a direct comp
...