SIST EN ISO 14713-2:2020

Zinc coatings - Guidelines and recommendations for the protection against corrosion of iron and steel in structures - Part 2: Hot dip galvanizing (ISO 14713-2:2019)

This document gives guidelines and recommendations for the general principles ofdesign appropriate to articles to be hot dip galvanized after fabrication (e.g.in accordance with ISO 1461) for the corrosion protection of, for example,articles that have been manufactured in accordance with EN 1090-2. This documentdoes not apply to hot dip galvanized coatings applied to continuous wire orsheet (e.g. to EN 10346).

Zinküberzüge - Leitfäden und Empfehlungen zum Schutz von Eisen- und Stahlkonstruktionen vor Korrosion - Teil 2: Feuerverzinken (ISO 14713-2:2019)

Dieses Dokument gibt Leitfäden und Empfehlungen für die allgemeinen Grundlagen der Gestaltung von Bauteilen, die zum Schutz gegen Korrosion einen Überzug durch Feuerverzinken nach der Fertigung (z. B. nach ISO 1461) erhalten, z. B. für Bauteile, die nach EN 1090 2 hergestellt wurden.
Dieses Dokument gilt nicht für Feuerverzinkungsüberzüge, die im kontinuierlichen Verfahren auf Stahldraht oder -band aufgebracht werden (z. B. nach EN 10346).

Revêtements de zinc - Lignes directrices et recommandations pour la protection contre la corrosion du fer et de l'acier dans les constructions - Partie 2: Galvanisation à chaud (ISO 14713-2:2019)

Le présent document donne des lignes directrices et des recommandations concernant les principes généraux de conception appropriés pour les pièces à galvaniser à chaud après fabrication (par exemple conformément à l'ISO 1461) utilisées pour la protection contre la corrosion, par exemple, de pièces qui ont été fabriquées conformément à l'EN 1090‑2.
Le présent document ne s'applique pas aux revêtements galvanisés à chaud appliqués sur fil ou sur tôle en continu (par exemple selon l'EN 10346).

Cinkove prevleke - Smernice in priporočila za zaščito železnih in jeklenih konstrukcij proti koroziji - 2. del: Vroče pocinkavanje (ISO 14713-2:2019)

Ta dokument vsebuje smernice in priporočila za splošna načela oblikovanja izdelkov, ki se jih za zaščito pred korozijo po izdelavi vroče pocinka (npr. v skladu s standardom ISO 1461), na primer izdelkov, ki so bili izdelani v skladu s standardom EN 1090-2. Ta dokument se ne uporablja za vroče pocinkane prevleke, ki se nanašajo na neprekinjeno žico ali pločevino (npr. v skladu s standardom EN 10346).

General Information

• Status: Published
• Public Enquiry End Date: 19-May-2019
• Publication Date: 13-Feb-2020
• ICS: 25.220.40 - Metallic coatings
• ICS: 91.080.10 - Metal structures
• ICS: 91.080.13 - Steel structures
• Technical Committee: IPKZ - Protection of metals against corrosion
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 22-Jan-2020
• Due Date: 28-Mar-2020
• Completion Date: 14-Feb-2020
• Ref Project: EN ISO 14713-2:2020 - Zinc coatings - Guidelines and recommendations for the protection against corrosion of iron and steel in structures - Part 2: Hot dip galvanizing (ISO 14713-2:2019)

Relations

• Replaces: SIST EN ISO 14713-2:2010 - Zinc coatings - Guidelines and recommendations for the protection against corrosion of iron and steel in structures - Part 2: Hot dip galvanizing (ISO 14713-2:2009)
• Effective Date: 01-Mar-2020

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 14713-2:2020
01-marec-2020
Nadomešča:
SIST EN ISO 14713-2:2010
Cinkove prevleke - Smernice in priporočila za zaščito železnih in jeklenih
konstrukcij proti koroziji - 2. del: Vroče pocinkavanje (ISO 14713-2:2019)

Zinc coatings - Guidelines and recommendations for the protection against corrosion of

iron and steel in structures - Part 2: Hot dip galvanizing (ISO 14713-2:2019)
Zinküberzüge - Leitfäden und Empfehlungen zum Schutz von Eisen- und
Stahlkonstruktionen vor Korrosion - Teil 2: Feuerverzinken (ISO 14713-2:2019)

Revêtements de zinc - Lignes directrices et recommandations pour la protection contre

la corrosion du fer et de l'acier dans les constructions - Partie 2: Galvanisation à chaud

(ISO 14713-2:2019)
Ta slovenski standard je istoveten z: EN ISO 14713-2:2020
ICS:
25.220.40 Kovinske prevleke Metallic coatings
91.080.10 Kovinske konstrukcije Metal structures
91.080.13 Jeklene konstrukcije Steel structures
SIST EN ISO 14713-2:2020 en

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

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SIST EN ISO 14713-2:2020
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SIST EN ISO 14713-2:2020
EN ISO 14713-2
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2020
EUROPÄISCHE NORM
ICS 25.220.40 Supersedes EN ISO 14713-2:2009
English Version
Zinc coatings - Guidelines and recommendations for the
protection against corrosion of iron and steel in structures
- Part 2: Hot dip galvanizing (ISO 14713-2:2019)

Revêtements de zinc - Lignes directrices et Zinküberzüge - Leitfäden und Empfehlungen zum

recommandations pour la protection contre la Schutz von Eisen- und Stahlkonstruktionen vor

corrosion du fer et de l'acier dans les constructions - Korrosion - Teil 2: Feuerverzinken (ISO 14713-2:2019)

Partie 2: Galvanisation à chaud (ISO 14713-2:2019)
This European Standard was approved by CEN on 20 December 2019.

This European Standard was corrected and reissued by the CEN-CENELEC Management Centre on 12 February 2020.

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 CEN-CENELEC Management Centre 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 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.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATIO N
EUROPÄISCHES KOMITEE FÜR NORMUN G
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. EN ISO 14713-2:2020 E

worldwide for CEN national Members.
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SIST EN ISO 14713-2:2020
EN ISO 14713-2:2020 (E)
Contents Page

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

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SIST EN ISO 14713-2:2020
EN ISO 14713-2:2020 (E)
European foreword

This document (EN ISO 14713-2:2020) has been prepared by Technical Committee ISO/TC 107

"Metallic and other inorganic coatings" in collaboration with Technical Committee CEN/TC 262

“Metallic and other inorganic coatings, including for corrosion protection and corrosion testing of

metals and alloys” the secretariat of which is held by BSI.

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 July 2020, and conflicting national standards shall be

withdrawn at the latest by July 2020.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 14713-2:2009.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: 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 the

United Kingdom.
Endorsement notice

The text of ISO 14713-2:2019 has been approved by CEN as EN ISO 14713-2:2020 without any

modification.
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SIST EN ISO 14713-2:2020
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SIST EN ISO 14713-2:2020
INTERNATIONAL ISO
STANDARD 14713-2
Second edition
2019-10
Zinc coatings — Guidelines and
recommendations for the protection
against corrosion of iron and steel in
structures —
Part 2:
Hot dip galvanizing
Revêtements de zinc — Lignes directrices et recommandations
pour la protection contre la corrosion du fer et de l'acier dans les
constructions —
Partie 2: Galvanisation à chaud
Reference number
ISO 14713-2:2019(E)
ISO 2019
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Design for hot dip galvanizing ................................................................................................................................................................ 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Surface preparation ............................................................................................................................................................................ 2

4.3 Procedures related to design considerations ............................................................................................................... 2

4.4 Design features ....................................................................................................................................................................................... 3

4.5 Tolerances ................................................................................................................................................................................................... 3

5 Design for storage and transport ........................................................................................................................................................ 3

6 Effect of article condition on quality of hot dip galvanizing .................................................................................... 4

6.1 General ........................................................................................................................................................................................................... 4

6.2 Material composition ........................................................................................................................................................................ 4

6.3 Castings ......................................................................................................................................................................................................... 5

6.4 Surface condition .................................................................................................................................................................................. 6

6.5 Influence of steel surface roughness on the hot dip galvanized coating thickness ...................... 6

6.6 Influence of thermal cutting processes and welding ............................................................................................. 6

6.6.1 Thermal cutting ................................................................................................................................................................ 6

6.6.2 Welding .................................................................................................................................................................................... 6

6.6.3 Free edges .............................................................................................................................................................................. 6

6.7 Effect of internal stresses in the steel article ................................................................................................................ 7

6.7.1 General...................................................................................................................................................................................... 7

6.7.2 Distortion cracking ........................................................................................................................................................ 7

6.7.3 Hydrogen embrittlement .......................................................................................................................................... 7

6.7.4 Strain age embrittlement .................. ........................................................................................................................ 7

6.7.5 Liquid metal assisted cracking or liquid metal embrittlement ............................................... 8

6.8 Large objects or thick steels ........................................................................................................................................................ 8

6.9 Hot dip galvanizing practice ........................................................................................................................................................ 8

7 Effect of hot dip galvanizing process on the article .......................................................................................................... 8

7.1 Dimensional tolerances on mating threads ................................................................................................................... 8

7.2 Effect of process heat ......................................................................................................................................................................... 9

8 After-treatments ................................................................................................................................................................................................... 9

Annex A (informative) Preferred designs of articles for hot dip galvanizing ..........................................................10

Bibliography .............................................................................................................................................................................................................................21

© ISO 2019 – All rights reserved iii
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso

.org/iso/foreword .html.

This document was prepared by Technical Committee ISO/TC 107, Metallic and other inorganic coatings,

Subcommittee SC 4, Hot dip coatings (galvanized, etc.).

This second edition cancels and replaces the first edition (ISO 14713-2:2009), which has been technically

revised. The main changes compared with the previous edition are as follows:

— minor technical changes have been made and two new notes have been added to Table 1;

— improvements have been made to the clarity of recommendations throughout Clause 6;

— extensive revisions have been made to the figures in Annex A;
— Tables A.1, A.2 and A.3 have been added in Annex A.
A list of all parts in the ISO 14713 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
Introduction

The protection afforded by the hot dip galvanized coating to the article will depend upon the method

of application of the coating, the design of the article and the specific environment to which the article

is exposed. The hot dip galvanized article can be further protected by the application of additional

coatings (outside the scope of this document), such as organic coatings (paints or powder coatings).

When applied to hot dip galvanized articles, this combination of coatings is often known as a “duplex

system”.

Specific product-related requirements, for which specific standards could exist (e.g. for hot dip

galvanized coatings on tubes or fasteners), take precedence over these general recommendations.

© ISO 2019 – All rights reserved v
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SIST EN ISO 14713-2:2020
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SIST EN ISO 14713-2:2020
INTERNATIONAL STANDARD ISO 14713-2:2019(E)
Zinc coatings — Guidelines and recommendations for
the protection against corrosion of iron and steel in
structures —
Part 2:
Hot dip galvanizing
1 Scope

This document gives guidelines and recommendations for the general principles of design appropriate

to articles to be hot dip galvanized after fabrication (e.g. in accordance with ISO 1461) for the corrosion

protection of, for example, articles that have been manufactured in accordance with EN 1090-2.

This document does not apply to hot dip galvanized coatings applied to continuous wire or sheet (e.g. to

EN 10346).
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.

ISO 8044, Corrosion of metals and alloys — Basic terms and definitions
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 8044 and the following apply.

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

— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
hot dip galvanizing

formation of a coating of zinc and/or zinc-iron alloys on iron and steel products by dipping prepared

steel or cast irons in the zinc melt
3.2
hot dip galvanized coating
coating obtained by hot dip galvanizing (3.1)

Note 1 to entry: The term “hot dip galvanized coating” is subsequently referred to as the “coating”.

3.3
duplex system
hot dip galvanized coating (3.2) with an additional paint or powder coating
© ISO 2019 – All rights reserved 1
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
4 Design for hot dip galvanizing
4.1 General

It is essential that the design of any article required to be galvanized should take into account not

only the function of the article and its method of manufacture, but also the limitations imposed by the

finish. Annex A illustrates some of the important design features, some of which are specific to hot dip

galvanizing.

Some internal stresses in the articles to be galvanized will be relieved during the hot dip galvanizing

process and this can cause deformation or damage to the coated article. These internal stresses arise

from the finishing operations at the fabrication stage, such as cold forming, welding, oxy-cutting or

drilling, and from the residual stresses inherited from the rolling mill.

The purchaser should seek the advice of the galvanizer before designing or making a product that is

subsequently to be hot dip galvanized, as it can be necessary to adapt the construction of the article for

the hot dip galvanizing process.
4.2 Surface preparation

The design and the materials used should permit good surface preparation. This is essential for the

production of a high-quality coating (see 6.4).

Graphite exposed at the surface of iron castings interferes with wetting by molten metal and those

castings that have been annealed can have silica particles in the surface layers that have to be removed

in order to obtain a good-quality coating. Grit blasting is recommended both before and after annealing.

4.3 Procedures related to design considerations

The hot dip bath and associated plant should be of adequate capacity to process the articles to be hot dip

coated with zinc. Preferably, articles should be designed to enable coating in a single dipping operation.

Articles that are too large for the available baths may be partially immersed and then reversed for

length or depth, so that a complete coating is obtained. Partial immersion (and then dipping for a second

time to complete the coating) is less common than the single, complete immersion operation.

All work is secured during immersion in the baths. Arrangements for lifting and handling should be

made before articles are delivered to the galvanizer. When necessary, the customer should consult

the galvanizer and advise of any limitations (e.g. on the use of existing holes). Lifting lugs are often

incorporated to assist general handling.

Articles may be held in racks or jigs. Some contact marks can be visible after hot dip galvanizing in such

cases. The dipping operation involves vertical movement out of the bath, but the parts being withdrawn

may be inclined at an angle.

The processing sequence requires the circulation of air, pretreatment liquids and zinc to all surfaces

of the article. Air pockets prevent local surface preparation and give uncoated surfaces. Liquids in

enclosed air vaporize at the hot dip galvanizing temperature of about 450 °C and the force generated

can cause buckling or explosions. Excess zinc can adhere poorly, can look unattractive and is wasteful.

Suitable articles, e.g. heat exchangers and gas cylinders, can, if required, be hot dip galvanized on the

outside only. This involves special techniques and equipment (e.g. to push the article into the bath

against the buoyancy of the molten zinc) and a specialist galvanizer should be consulted in advance.

Hot dip galvanizing of hollow sections ensures protection of both internal and external surfaces. Small

amounts of trapped zinc ash can be unavoidable within hollow sections and, for certain shapes and

designs, cannot be removed.
2 © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
4.4 Design features

Preferred design features for articles to be hot dip galvanized are shown in Annex A.

WARNING — It is essential that sealed compartments be avoided or be vented, otherwise there

is a serious risk of explosion that could cause serious injury to operators. This aspect of design

shall be given careful consideration and is essential in order to maintain satisfactory standards

of health and safety for operators.

In addition to provision for venting and draining of tubular fabrications, holes also allow a coating to

be formed on the inside surfaces and therefore ensure better protection for the article. Occasionally, at

sufficiently high levels of residual stress in the article, stress relief can occur at the hot dip galvanizing

temperature. This is one of the main causes of unexpected distortion or cracking of the steel article.

Symmetrical sections are preferred and, as far as possible, large variations in thickness or cross-section,

e.g. thin sheet welded to thick angles, should be avoided. Welding and fabrication techniques should be

chosen to minimize the introduction of unbalanced stresses. Differential thermal expansion should be

minimized during welding and processing. Heat treatment can be desirable before hot dip galvanizing.

The purchaser should discuss with the galvanizer the requirements for coating and assembly of

fabricated articles before galvanizing. Compact sub-assemblies (which occupy minimum bath space)

are the most economical to galvanize. Welding is preferable before hot dip galvanizing, to ensure a

continuous hot dip galvanized coating over the weld.

Articles should be designed so as to assist the access and drainage of molten metal and so that air locks

are avoided. A smooth profile, avoiding unnecessary edges and corners, assists hot dip galvanizing.

This, combined with bolting after galvanizing, improves long-term corrosion resistance.

Holes that are necessary in structures for the hot dip galvanizing process are preferably made before

assembly and by cutting or grinding off corners of sections; this facilitates the absence of “pockets” in

which excess molten zinc can solidify. When already assembled, burning could be the optimum method

of producing holes, as the space available for drilling may not allow the hole to be close enough to the

edge or corners.

Internal venting of hollow sections should be avoided. If internal venting is unavoidable, it should

be agreed in advance with the galvanizer [see also ISO 1461:2009, A.2, e)] and the customer should

ensure that:
a) the holes are of maximum possible size;

b) provision for internal venting is adequately documented (e.g. by photography) before assembly.

4.5 Tolerances

The thickness of the coating is determined mainly by the nature and thickness of the steel. On mating

surfaces and at holes, extra tolerance should be provided to allow for the thickness of the coating metal.

For coatings on flat surfaces, an allowance of at least 1 mm has been found satisfactory. See ISO 1461

for definitions of significant surfaces and acceptance criteria for the coating. For threaded work, for

example, for hot dip galvanized and centrifuged nuts and bolts, current practices differ according to the

country. See 7.1.
5 Design for storage and transport

Hot dip galvanized articles should be stacked securely so that the articles can be handled, stored and

transported safely.

Where there is a specific need to minimize the development of wet-storage staining (primarily basic

zinc oxide and zinc hydroxide, formed on the surface of the galvanized coating during storage of articles

in humid conditions), this should be communicated by the purchaser to the galvanizer at the time of

ordering and any relevant control measures should be agreed upon.
© ISO 2019 – All rights reserved 3
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)

Such measures can include, for example, storage of articles such that free movement of air across the

surfaces of the article is allowed, the use of spacers to minimize contact areas on the work, chemical

post-treatment or avoidance of close nesting of work (where the design allows this). Shrink wrapping

can lead to water retention within the articles and subsequent wet-storage staining.

In accordance with ISO 1461, the presence of wet-storage staining is not a cause for rejection, provided

the coating thickness remains above the specified minimum requirements at the time of acceptance

inspection.
6 Effect of article condition on quality of hot dip galvanizing
6.1 General

Most steels can be hot dip galvanized in accordance with ISO 1461. This includes unalloyed carbon

steels (see, e.g., EN 10025-2), fine-grained steels (see, e.g., EN 10025-3 and EN 10025-4), quenched

and tempered steels, hollow sections that are hot finished (see, e.g., EN 10210-1), hollow sections that

are cold finished (see, e.g., EN 10219-1), reinforcement steels (see, e.g., EN 10080 and EN 10348-2),

fastener grade steels [see, e.g., ISO 898 (all parts)], grey cast iron (see, e.g., EN 1561) and malleable cast

iron (see, e.g., EN 1562). Where other ferrous metals are to be galvanized, adequate information or

samples should be provided by the purchaser for the galvanizer to decide whether these steels can be

satisfactorily galvanized. Sulfur-containing free-cutting steels are normally unsuitable. Stainless steels

are unsuitable.
6.2 Material composition

Certain elements, in particular silicon (Si) and phosphorus (P), in the steel surface can affect hot

dip galvanizing by prolonging the reaction between iron and molten zinc. Therefore, certain steel

compositions can achieve more consistent coatings with regard to appearance, thickness and

smoothness. The prior history of the steel (e.g. whether hot rolled or cold rolled) can also affect its

reaction with molten zinc. Where aesthetics are important or where particular coating thickness

or surface smoothness criteria exist, specialist advice on steel selection should be sought prior to

fabrication of the article or hot dip galvanizing.

Table 1 gives simplified guidance on steel compositions that are associated with certain typical coating

characteristics when galvanizing is carried out at temperatures of 440 °C to 460 °C.

4 © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14
...

SLOVENSKI STANDARD
SIST EN ISO 14713-2:2020
01-marec-2020
Nadomešča:
SIST EN ISO 14713-2:2010
Cinkove prevleke - Smernice in priporočila za zaščito železnih in jeklenih
konstrukcij proti koroziji - 2. del: Vroče pocinkavanje (ISO 14713-2:2019)

Zinc coatings - Guidelines and recommendations for the protection against corrosion of

iron and steel in structures - Part 2: Hot dip galvanizing (ISO 14713-2:2019)
Zinküberzüge - Leitfäden und Empfehlungen zum Schutz von Eisen- und
Stahlkonstruktionen vor Korrosion - Teil 2: Feuerverzinken (ISO 14713-2:2019)

Revêtements de zinc - Lignes directrices et recommandations pour la protection contre

la corrosion du fer et de l'acier dans les constructions - Partie 2: Galvanisation à chaud

(ISO 14713-2:2019)
Ta slovenski standard je istoveten z: EN ISO 14713-2:2020
ICS:
25.220.40 Kovinske prevleke Metallic coatings
91.080.10 Kovinske konstrukcije Metal structures
91.080.13 Jeklene konstrukcije Steel structures
SIST EN ISO 14713-2:2020 en

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

---------------------- Page: 1 ----------------------
SIST EN ISO 14713-2:2020
---------------------- Page: 2 ----------------------
SIST EN ISO 14713-2:2020
EN ISO 14713-2
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2020
EUROPÄISCHE NORM
ICS 25.220.40 Supersedes EN ISO 14713-2:2009
English Version
Zinc coatings - Guidelines and recommendations for the
protection against corrosion of iron and steel in structures
- Part 2: Hot dip galvanizing (ISO 14713-2:2019)

Revêtements de zinc - Lignes directrices et Zinküberzüge - Leitfäden und Empfehlungen zum

recommandations pour la protection contre la Schutz von Eisen- und Stahlkonstruktionen vor

corrosion du fer et de l'acier dans les constructions - Korrosion - Teil 2: Feuerverzinken (ISO 14713-2:2019)

Partie 2: Galvanisation à chaud (ISO 14713-2:2019)
This European Standard was approved by CEN on 20 December 2019.

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 CEN-CENELEC Management Centre 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 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.
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. EN ISO 14713-2:2020 E

worldwide for CEN national Members.
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SIST EN ISO 14713-2:2020
EN ISO 14713-2:2020 (E)
Contents Page

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

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SIST EN ISO 14713-2:2020
EN ISO 14713-2:2020 (E)
European foreword

This document (EN ISO 14713-2:2020) has been prepared by Technical Committee ISO/TC 107

"Metallic and other inorganic coatings" in collaboration with Technical Committee CEN/TC 262

“Metallic and other inorganic coatings, including for corrosion protection and corrosion testing of

metals and alloys” the secretariat of which is held by BSI.

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 July 2020, and conflicting national standards shall be

withdrawn at the latest by April 2020.

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. CEN shall not be held responsible for identifying any or all such patent rights.

This document supersedes EN ISO 14713-2:2009.

According to the CEN-CENELEC Internal Regulations, the national standards organizations of the

following countries are bound to implement this European Standard: 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 the

United Kingdom.
Endorsement notice

The text of ISO 14713-2:2019 has been approved by CEN as EN ISO 14713-2:2020 without any

modification.
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SIST EN ISO 14713-2:2020
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SIST EN ISO 14713-2:2020
INTERNATIONAL ISO
STANDARD 14713-2
Second edition
2019-10
Zinc coatings — Guidelines and
recommendations for the protection
against corrosion of iron and steel in
structures —
Part 2:
Hot dip galvanizing
Revêtements de zinc — Lignes directrices et recommandations
pour la protection contre la corrosion du fer et de l'acier dans les
constructions —
Partie 2: Galvanisation à chaud
Reference number
ISO 14713-2:2019(E)
ISO 2019
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2019

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting

on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address

below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction ..................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ...................................................................................................................................................................................... 1

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Design for hot dip galvanizing ................................................................................................................................................................ 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Surface preparation ............................................................................................................................................................................ 2

4.3 Procedures related to design considerations ............................................................................................................... 2

4.4 Design features ....................................................................................................................................................................................... 3

4.5 Tolerances ................................................................................................................................................................................................... 3

5 Design for storage and transport ........................................................................................................................................................ 3

6 Effect of article condition on quality of hot dip galvanizing .................................................................................... 4

6.1 General ........................................................................................................................................................................................................... 4

6.2 Material composition ........................................................................................................................................................................ 4

6.3 Castings ......................................................................................................................................................................................................... 5

6.4 Surface condition .................................................................................................................................................................................. 6

6.5 Influence of steel surface roughness on the hot dip galvanized coating thickness ...................... 6

6.6 Influence of thermal cutting processes and welding ............................................................................................. 6

6.6.1 Thermal cutting ................................................................................................................................................................ 6

6.6.2 Welding .................................................................................................................................................................................... 6

6.6.3 Free edges .............................................................................................................................................................................. 6

6.7 Effect of internal stresses in the steel article ................................................................................................................ 7

6.7.1 General...................................................................................................................................................................................... 7

6.7.2 Distortion cracking ........................................................................................................................................................ 7

6.7.3 Hydrogen embrittlement .......................................................................................................................................... 7

6.7.4 Strain age embrittlement .................. ........................................................................................................................ 7

6.7.5 Liquid metal assisted cracking or liquid metal embrittlement ............................................... 8

6.8 Large objects or thick steels ........................................................................................................................................................ 8

6.9 Hot dip galvanizing practice ........................................................................................................................................................ 8

7 Effect of hot dip galvanizing process on the article .......................................................................................................... 8

7.1 Dimensional tolerances on mating threads ................................................................................................................... 8

7.2 Effect of process heat ......................................................................................................................................................................... 9

8 After-treatments ................................................................................................................................................................................................... 9

Annex A (informative) Preferred designs of articles for hot dip galvanizing ..........................................................10

Bibliography .............................................................................................................................................................................................................................21

© ISO 2019 – All rights reserved iii
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www .iso .org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to the

World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso

.org/iso/foreword .html.

This document was prepared by Technical Committee ISO/TC 107, Metallic and other inorganic coatings,

Subcommittee SC 4, Hot dip coatings (galvanized, etc.).

This second edition cancels and replaces the first edition (ISO 14713-2:2009), which has been technically

revised. The main changes compared with the previous edition are as follows:

— minor technical changes have been made and two new notes have been added to Table 1;

— improvements have been made to the clarity of recommendations throughout Clause 6;

— extensive revisions have been made to the figures in Annex A;
— Tables A.1, A.2 and A.3 have been added in Annex A.
A list of all parts in the ISO 14713 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www .iso .org/members .html.
iv © ISO 2019 – All rights reserved
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
Introduction

The protection afforded by the hot dip galvanized coating to the article will depend upon the method

of application of the coating, the design of the article and the specific environment to which the article

is exposed. The hot dip galvanized article can be further protected by the application of additional

coatings (outside the scope of this document), such as organic coatings (paints or powder coatings).

When applied to hot dip galvanized articles, this combination of coatings is often known as a “duplex

system”.

Specific product-related requirements, for which specific standards could exist (e.g. for hot dip

galvanized coatings on tubes or fasteners), take precedence over these general recommendations.

© ISO 2019 – All rights reserved v
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SIST EN ISO 14713-2:2020
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SIST EN ISO 14713-2:2020
INTERNATIONAL STANDARD ISO 14713-2:2019(E)
Zinc coatings — Guidelines and recommendations for
the protection against corrosion of iron and steel in
structures —
Part 2:
Hot dip galvanizing
1 Scope

This document gives guidelines and recommendations for the general principles of design appropriate

to articles to be hot dip galvanized after fabrication (e.g. in accordance with ISO 1461) for the corrosion

protection of, for example, articles that have been manufactured in accordance with EN 1090-2.

This document does not apply to hot dip galvanized coatings applied to continuous wire or sheet (e.g. to

EN 10346).
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.

ISO 8044, Corrosion of metals and alloys — Basic terms and definitions
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 8044 and the following apply.

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

— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
3.1
hot dip galvanizing

formation of a coating of zinc and/or zinc-iron alloys on iron and steel products by dipping prepared

steel or cast irons in the zinc melt
3.2
hot dip galvanized coating
coating obtained by hot dip galvanizing (3.1)

Note 1 to entry: The term “hot dip galvanized coating” is subsequently referred to as the “coating”.

3.3
duplex system
hot dip galvanized coating (3.2) with an additional paint or powder coating
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
4 Design for hot dip galvanizing
4.1 General

It is essential that the design of any article required to be galvanized should take into account not

only the function of the article and its method of manufacture, but also the limitations imposed by the

finish. Annex A illustrates some of the important design features, some of which are specific to hot dip

galvanizing.

Some internal stresses in the articles to be galvanized will be relieved during the hot dip galvanizing

process and this can cause deformation or damage to the coated article. These internal stresses arise

from the finishing operations at the fabrication stage, such as cold forming, welding, oxy-cutting or

drilling, and from the residual stresses inherited from the rolling mill.

The purchaser should seek the advice of the galvanizer before designing or making a product that is

subsequently to be hot dip galvanized, as it can be necessary to adapt the construction of the article for

the hot dip galvanizing process.
4.2 Surface preparation

The design and the materials used should permit good surface preparation. This is essential for the

production of a high-quality coating (see 6.4).

Graphite exposed at the surface of iron castings interferes with wetting by molten metal and those

castings that have been annealed can have silica particles in the surface layers that have to be removed

in order to obtain a good-quality coating. Grit blasting is recommended both before and after annealing.

4.3 Procedures related to design considerations

The hot dip bath and associated plant should be of adequate capacity to process the articles to be hot dip

coated with zinc. Preferably, articles should be designed to enable coating in a single dipping operation.

Articles that are too large for the available baths may be partially immersed and then reversed for

length or depth, so that a complete coating is obtained. Partial immersion (and then dipping for a second

time to complete the coating) is less common than the single, complete immersion operation.

All work is secured during immersion in the baths. Arrangements for lifting and handling should be

made before articles are delivered to the galvanizer. When necessary, the customer should consult

the galvanizer and advise of any limitations (e.g. on the use of existing holes). Lifting lugs are often

incorporated to assist general handling.

Articles may be held in racks or jigs. Some contact marks can be visible after hot dip galvanizing in such

cases. The dipping operation involves vertical movement out of the bath, but the parts being withdrawn

may be inclined at an angle.

The processing sequence requires the circulation of air, pretreatment liquids and zinc to all surfaces

of the article. Air pockets prevent local surface preparation and give uncoated surfaces. Liquids in

enclosed air vaporize at the hot dip galvanizing temperature of about 450 °C and the force generated

can cause buckling or explosions. Excess zinc can adhere poorly, can look unattractive and is wasteful.

Suitable articles, e.g. heat exchangers and gas cylinders, can, if required, be hot dip galvanized on the

outside only. This involves special techniques and equipment (e.g. to push the article into the bath

against the buoyancy of the molten zinc) and a specialist galvanizer should be consulted in advance.

Hot dip galvanizing of hollow sections ensures protection of both internal and external surfaces. Small

amounts of trapped zinc ash can be unavoidable within hollow sections and, for certain shapes and

designs, cannot be removed.
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
4.4 Design features

Preferred design features for articles to be hot dip galvanized are shown in Annex A.

WARNING — It is essential that sealed compartments be avoided or be vented, otherwise there

is a serious risk of explosion that could cause serious injury to operators. This aspect of design

shall be given careful consideration and is essential in order to maintain satisfactory standards

of health and safety for operators.

In addition to provision for venting and draining of tubular fabrications, holes also allow a coating to

be formed on the inside surfaces and therefore ensure better protection for the article. Occasionally, at

sufficiently high levels of residual stress in the article, stress relief can occur at the hot dip galvanizing

temperature. This is one of the main causes of unexpected distortion or cracking of the steel article.

Symmetrical sections are preferred and, as far as possible, large variations in thickness or cross-section,

e.g. thin sheet welded to thick angles, should be avoided. Welding and fabrication techniques should be

chosen to minimize the introduction of unbalanced stresses. Differential thermal expansion should be

minimized during welding and processing. Heat treatment can be desirable before hot dip galvanizing.

The purchaser should discuss with the galvanizer the requirements for coating and assembly of

fabricated articles before galvanizing. Compact sub-assemblies (which occupy minimum bath space)

are the most economical to galvanize. Welding is preferable before hot dip galvanizing, to ensure a

continuous hot dip galvanized coating over the weld.

Articles should be designed so as to assist the access and drainage of molten metal and so that air locks

are avoided. A smooth profile, avoiding unnecessary edges and corners, assists hot dip galvanizing.

This, combined with bolting after galvanizing, improves long-term corrosion resistance.

Holes that are necessary in structures for the hot dip galvanizing process are preferably made before

assembly and by cutting or grinding off corners of sections; this facilitates the absence of “pockets” in

which excess molten zinc can solidify. When already assembled, burning could be the optimum method

of producing holes, as the space available for drilling may not allow the hole to be close enough to the

edge or corners.

Internal venting of hollow sections should be avoided. If internal venting is unavoidable, it should

be agreed in advance with the galvanizer [see also ISO 1461:2009, A.2, e)] and the customer should

ensure that:
a) the holes are of maximum possible size;

b) provision for internal venting is adequately documented (e.g. by photography) before assembly.

4.5 Tolerances

The thickness of the coating is determined mainly by the nature and thickness of the steel. On mating

surfaces and at holes, extra tolerance should be provided to allow for the thickness of the coating metal.

For coatings on flat surfaces, an allowance of at least 1 mm has been found satisfactory. See ISO 1461

for definitions of significant surfaces and acceptance criteria for the coating. For threaded work, for

example, for hot dip galvanized and centrifuged nuts and bolts, current practices differ according to the

country. See 7.1.
5 Design for storage and transport

Hot dip galvanized articles should be stacked securely so that the articles can be handled, stored and

transported safely.

Where there is a specific need to minimize the development of wet-storage staining (primarily basic

zinc oxide and zinc hydroxide, formed on the surface of the galvanized coating during storage of articles

in humid conditions), this should be communicated by the purchaser to the galvanizer at the time of

ordering and any relevant control measures should be agreed upon.
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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)

Such measures can include, for example, storage of articles such that free movement of air across the

surfaces of the article is allowed, the use of spacers to minimize contact areas on the work, chemical

post-treatment or avoidance of close nesting of work (where the design allows this). Shrink wrapping

can lead to water retention within the articles and subsequent wet-storage staining.

In accordance with ISO 1461, the presence of wet-storage staining is not a cause for rejection, provided

the coating thickness remains above the specified minimum requirements at the time of acceptance

inspection.
6 Effect of article condition on quality of hot dip galvanizing
6.1 General

Most steels can be hot dip galvanized in accordance with ISO 1461. This includes unalloyed carbon

steels (see, e.g., EN 10025-2), fine-grained steels (see, e.g., EN 10025-3 and EN 10025-4), quenched

and tempered steels, hollow sections that are hot finished (see, e.g., EN 10210-1), hollow sections that

are cold finished (see, e.g., EN 10219-1), reinforcement steels (see, e.g., EN 10080 and EN 10348-2),

fastener grade steels [see, e.g., ISO 898 (all parts)], grey cast iron (see, e.g., EN 1561) and malleable cast

iron (see, e.g., EN 1562). Where other ferrous metals are to be galvanized, adequate information or

samples should be provided by the purchaser for the galvanizer to decide whether these steels can be

satisfactorily galvanized. Sulfur-containing free-cutting steels are normally unsuitable. Stainless steels

are unsuitable.
6.2 Material composition

Certain elements, in particular silicon (Si) and phosphorus (P), in the steel surface can affect hot

dip galvanizing by prolonging the reaction between iron and molten zinc. Therefore, certain steel

compositions can achieve more consistent coatings with regard to appearance, thickness and

smoothness. The prior history of the steel (e.g. whether hot rolled or cold rolled) can also affect its

reaction with molten zinc. Where aesthetics are important or where particular coating thickness

or surface smoothness criteria exist, specialist advice on steel selection should be sought prior to

fabrication of the article or hot dip galvanizing.

Table 1 gives simplified guidance on steel compositions that are associated with certain typical coating

characteristics when galvanizing is carried out at temperatures of 440 °C to 460 °C.

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SIST EN ISO 14713-2:2020
ISO 14713-2:2019(E)
Table 1 — Coating characteristics related to steel composition
Category Typical levels of reactive Additional
...