oSIST prEN ISO 14713-2:2026

• Abstract:

  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).

• Status: Not Published
• Public Enquiry End Date: 30-Jul-2026
• 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: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 27-May-2026
• Due Date: 14-Oct-2026
• Completion Date: 03-Aug-2026
• Ref Project: prEN ISO 14713-2 - Zinc coatings - Guidelines and recommendations for the protection against corrosion of iron and steel in structures - Part 2: Requirements and recommendations for articles to be hot dip galvanized (ISO/DIS 14713-2:2026)

• Revises: 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)
• Effective Date: 02-Oct-2024

Overview

oSIST prEN ISO 14713-2:2026:2026 provides essential guidelines and recommendations for the design and manufacture of iron and steel articles that will be hot dip galvanized after fabrication. This European and International Standard, developed under CEN (European Committee for Standardization) and ISO, serves to help manufacturers, designers, and specifiers ensure optimal corrosion protection for steel structures through hot dip zinc coatings. The document focuses on practical aspects of design, material selection, and fabrication to facilitate high-quality hot dip galvanizing and long-term durability.

This standard specifically addresses batch galvanizing of fabricated steel products, as outlined in standards such as ISO 1461 and for articles produced according to EN 1090-2. It does not apply to hot dip galvanized coatings on continuous wire or sheet (e.g., those covered by EN 10346).

Key Topics

• Design Principles for Hot Dip Galvanizing

  • Recommendations for article geometry, venting, and drainage to facilitate proper zinc flow and coating consistency.
  • Advises early consultation with the galvanizer to resolve requirements and potential constraints.

• Process and Handling Considerations

  • Guidance for ensuring articles are sized and constructed for efficient handling during galvanizing.
  • Requirements for lifting lugs, jigs, or other attachments for safe movement throughout the process.

• Material and Surface Preparation

  • Assessing steel composition (silicon, phosphorus) for optimal coating thickness and appearance.
  • Recommendations on surface cleanliness, including removal of oils, paints, and welding residues that may impede coating adhesion.

• Effect of Fabrication on Galvanized Coating

  • Discussion of the impact of welding, cutting, and residual stresses on final coating quality.
  • Mitigation of risks such as distortion, cracking, and embrittlement during galvanizing.

• Post-treatment, Storage, and Transport

  • Guidance for minimizing wet storage staining and ensuring coatings are not damaged during transportation or long-term storage.

Applications

oSIST prEN ISO 14713-2:2026:2026 is essential for a wide range of industries where hot dip galvanized coatings are crucial for protection against corrosion, especially in construction, civil engineering, infrastructure, and industrial manufacturing. Typical applications include:

• Structural Steelwork: Beams, columns, and frameworks that demand high corrosion resistance, especially in outdoor or aggressive environments.
• Bridges and Infrastructure: Large-scale fabricated components such as trusses, railings, and barriers.
• Architectural and Building Components: Facades, canopies, support structures, stairways, and fixtures.
• Utility and Industrial Installations: Poles, towers, pipe supports, and machinery bases.

Following the recommendations in this standard helps ensure that the hot dip galvanizing process delivers uniform coating, robust performance, and compliance with both project requirements and related standards.

Related Standards

To achieve the best results in corrosion protection and ensure compatibility, reference the following standards alongside oSIST prEN ISO 14713-2:2026:2026:

• ISO 1461: Hot dip galvanized coatings on fabricated iron and steel articles - Specifications and test methods
• EN 1090-2: Execution of steel structures and aluminium structures - Technical requirements for steel structures
• EN 10346: Continuously hot-dip coated steel flat products
• ISO 8044: Corrosion of metals and alloys - Basic terms and definitions

Manufacturers and project specifiers should consult these and other relevant standards for comprehensive guidance on materials, processes, and quality control throughout the lifecycle of galvanized steel structures.

By adhering to oSIST prEN ISO 14713-2:2026:2026, stakeholders can significantly enhance the durability and lifespan of steel structures, reduce maintenance costs, and ensure optimal performance in corrosive environments.

SLOVENSKI STANDARD
01-julij-2026
Cinkove prevleke - Smernice in priporočila za zaščito železnih in jeklenih
konstrukcij proti koroziji - 2. del: Zahteve in priporočila za izdelke, namenjene
vročemu pocinkanju (ISO/DIS 14713-2:2026)
Zinc coatings - Guidelines and recommendations for the protection against corrosion of
iron and steel in structures - Part 2: Requirements and recommendations for articles to
be hot dip galvanized (ISO/DIS 14713-2:2026)
Zinküberzüge - Leitfäden und Empfehlungen zum Schutz von Eisen- und
Stahlkonstruktionen vor Korrosion - Teil 2: Feuerverzinken (ISO/DIS 14713-2:2026)
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/DIS 14713-2:2026)
Ta slovenski standard je istoveten z: prEN ISO 14713-2
ICS:
25.220.40 Kovinske prevleke Metallic coatings
91.080.10 Kovinske konstrukcije Metal structures
91.080.13 Jeklene konstrukcije Steel structures
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
International
Standard
ISO/DIS 14713-2
ISO/TC 107/SC 4
Zinc coatings — Guidelines
Secretariat: BSI
and recommendations for the
Voting begins on:
protection against corrosion of iron
and steel in structures —
2026-05-15
Part 2:
Voting terminates on:
Requirements and
recommendations for articles to be 2026-08-07
hot dip galvanized
ICS: 25.220.40
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENTS AND APPROVAL. IT
IS THEREFORE SUBJECT TO CHANGE
AND MAY NOT BE REFERRED TO AS AN
INTERNATIONAL STANDARD UNTIL
PUBLISHED AS SUCH.
This document is circulated as received from the committee secretariat.
IN ADDITION TO THEIR EVALUATION AS
BEING ACCEPTABLE FOR INDUSTRIAL,
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
ISO/CEN PARALLEL PROCESSING
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS.
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.
Reference number
ISO/DIS 14713-2:2026(en)
ISO/DIS 14713-2:2026(en)
© ISO 2026
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.
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Published in Switzerland
ii
ISO/DIS 14713-2:2026(en)
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 Process considerations .2
4.2.1 Size and handling of articles .2
4.2.2 Venting and draining of articles .2
4.3 Design features .3
4.3.1 General .3
4.3.2 Minimising residual stress .3
4.3.3 Providing adequate venting and draining .3
4.4 Tolerances .4
5 Storage and transport . 4
6 Effect of article condition . 4
6.1 General .4
6.2 Steel composition .4
6.3 Castings .5
6.4 Surface condition .6
6.4.1 Surface cleanliness .6
6.4.2 Influence of steel surface roughness on the galvanized coating thickness .6
6.5 Influence of thermal cutting processes and welding .6
6.5.1 Thermal cutting .6
6.5.2 Welding .6
6.5.3 Free edges.7
6.6 Effect of internal stresses in the steel article .7
6.6.1 Distortion .7
6.6.2 Distortion cracking .7
6.6.3 Hydrogen embrittlement .7
6.6.4 Strain age embrittlement .8
6.6.5 Liquid metal assisted cracking or liquid metal embrittlement .8
6.7 Large objects or thick steels .8
6.8 Hot dip galvanizing .8
7 Dimensional tolerances on mating threads . 9
8 After-treatments . 9
Annex A (informative) Design of articles for hot dip galvanizing .10
Annex B (informative) Checklist for the purchaser when ordering articles to be hot dip
galvanized .21
Bibliography .23

iii
ISO/DIS 14713-2:2026(en)
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 third edition, which has been technically revised, cancels and replaces the second edition
(ISO 14713-2:2019). The main changes compared with the previous edition are as follows:
— Title has been amended to clarify the purpose of document
— Clause 3 has been aligned to ISO 1461 with definitions of ‘galvanizer ’ and ‘wet storage stain ’ now
included
— Clause 4 has been extensively edited to make requirements on designers/manufacturers clearer and
avoid repetition of information
— Clause 6 has been extensively revised
— Information on castings has been consolidated into 6.3
— A new diagram (Figure 1 ) and explanation of the k-area of beams has been added in 6.5
— Significant revisions made to Clause 6.6 (now 6.5 )
— Small technical correction has been made to Table A.2
— Sub-clauses have been added to Annex A to better organise the information provided
— New Annex B added to provide a simplified checklist of actions for designers/manufacturers.
— Editorial changes to simplify language and apply a consistent use of terms.
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/DIS 14713-2:2026(en)
Introduction
Hot dip galvanized coatings are applied to fabricated iron or steel articles through immersion in a bath
of molten zinc to apply a highly durable and abrasion resistant protective coating that is metallurgically
[1]
bonded to the substrate (see ISO 1461 ).
Application of a galvanized coating after fabrication or manufacture of the steel article ensures that the
galvanized coating provides complete coverage for the article. It is therefore necessary to optimize design
and fabrication of steel articles to ensure their suitability for the batch hot dip galvanizing process. This
includes aspects such as design detailing to allow access or drainage of molten zinc and venting of air; choice
of steel grades and methods of fabrication.
This document provides requirements and recommendations for the design, fabrication and manufacture of
iron or steel articles to be hot dip galvanized.

v
DRAFT International Standard ISO/DIS 14713-2:2026(en)
Zinc coatings — Guidelines and recommendations for the
protection against corrosion of iron and steel in structures —
Part 2:
Requirements and recommendations for articles to be hot dip
galvanized
1 Scope
This document gives requirements and recommendations for the general principles of design of articles to
[1]
be hot dip galvanized after fabrication (e.g. in accordance with ISO 1461 ) for the corrosion protection of,
[2]
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
[3]
10346 ).
2 Normative references
There are no normative references in this document.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 8044and 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 galvanized coating of either zinc or zinc iron alloys, or both, on fabricated iron or steel articles
by dipping in a zinc melt
3.2
hot dip galvanized coating
galvanized coating
coating obtained by hot dip galvanizing (3.1)
3.3
duplex system
hot dip galvanized coating (3.2) with an additional liquid paint or powder coating
3.4
galvanizer
company or organization that operates a plant for the hot dip galvanizing (3.1) of batches of fabricated iron
or steel articles
ISO/DIS 14713-2:2026(en)
3.5
wet storage stain
surface stain resulting from the formation of zinc corrosion products (usually zinc hydroxide and zinc oxide)
when freshly galvanized steel is stored or transported in moist or humid conditions
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 the function of
the article, its method of manufacture and also the limitations imposed by the finish. Annex A gives guidance
that should be followed for a selection of important design situations. The principles of providing venting for
enclosed areas and adequate access and drainage for molten zinc that are given in Annex A can be extended
to other design situations.
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 article. These internal stresses arise from 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 manufacturing an article that is
to be hot dip galvanized, as it can be necessary to adapt the design or manufacture of the article for the hot
dip galvanizing process.
The design and the materials used should permit good surface preparation during galvanizing to ensure a
reaction between the steel and molten zinc. This is essential for the production of the galvanized coating
(see 6.4).
4.2 Process considerations
4.2.1 Size and handling of articles
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
galvanized coating is obtained.
NOTE Partial immersion and then dipping for a second time to complete the coating is termed 'double-dipping'
and can result in increased handling. It is less common than the single, complete immersion operation.
The galvanizing bath and associated plant should be of adequate lifting capacity and dimensions to process
the articles to be hot dip galvanized.
Articles are secured, for example to jigs, then usually moved through the process by overhead cranes.
Arrangements for lifting and handling should be made before articles are delivered to the galvanizer. The
purchaser 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. Lifting lugs or existing holes to be used for
handling purposes shall be of an appropriate size and strength.
Articles may be suspended by chains, hooks or wires. Articles may also be held in racks or jigs. In each
case, some contact marks can be visible after hot dip galvanizing. The dipping operation involves vertical
movement out of the bath, but the parts being withdrawn may be inclined at an angle.
4.2.2 Venting and draining of articles
The galvanizing process requires the circulation of air, pretreatment liquids and molten zinc to all surfaces of
the article. Air pockets prevent local surface preparation and give uncoated surfaces. Liquids and moisture
in enclosed spaces vaporize at the hot dip galvanizing temperature of approximately 450 °C and the force
generated can cause buckling of the article or explosions and, in extreme cases, a safety hazard for operators

ISO/DIS 14713-2:2026(en)
of the galvanizing process. Optimal drainage of molten zinc improves appearance and improves resource
efficiency.
Hot dip galvanizing of hollow articles 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.
Certain 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.
4.3 Design features
4.3.1 General
Recommended design features for articles to be hot dip galvanized are given in Annex A. Articles should be
designed so as to assist the access and drainage of molten metal and so that air locks are avoided 4.2.2
WARNING — This aspect of design shall be given careful consideration and is essential to maintain
satisfactory standards of health and safety for operators of the galvanizing process.
A smooth profile, avoiding unnecessary edges and corners, assists hot dip galvanizing. This, combined with
bolting after galvanizing, improves long-term corrosion resistance.
4.3.2 Minimising residual stress
The hot dip galvanizing process involves dipping fabricated steel articles in a bath of molten zinc at a
temperature of approximately 450 °C and withdrawing them when the metallurgical reaction, that develops
the coating, is complete. Residual stress may be present in articles due to manufacturing processes or
fabrication procedures. At sufficiently high levels of residual stress in the article, stress relief can occur at
the hot dip galvanizing temperature (see 6.6.1) . This is one of the main causes of unexpected distortion or
cracking of a steel article. Symmetrical sections are recommended 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 to reduce residual stress in the article.
Before galvanizing, the purchaser should discuss with the galvanizer the requirements for coating and
subsequent assembly of fabricated articles. Compact sub-assemblies (which occupy minimum bath space),
that are assembled, by bolting, after galvanizing, are preferable. Welding is preferable before galvanizing, to
ensure a continuous galvanized coating over the weld.
4.3.3 Providing adequate venting and draining
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, thermal cutting could be the optimum method of
producing holes, for example when the space available for drilling does not allow the hole to be close enough
to the edge or corners (see also 6.5.1).
Internal venting of hollow sections should be avoided. If internal venting is unavoidable, it should be agreed
[1]
in advance with the galvanizer (see also ISO 1461 ) and the purchaser 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.

ISO/DIS 14713-2:2026(en)
4.4 Tolerances
The thickness of the galvanized 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 galvanized coatings on flat surfaces, an allowance of at least 1 mm has been found satisfactory.
[1]
See ISO 1461 for definitions of significant surfaces and acceptance criteria for the galvanized coating. For
threaded work, for example, for hot dip galvanized and centrifuged nuts and bolts, current practices differ
according to the country. See Clause 7.
5 Storage and transport
Hot dip galvanized articles should be stacked securely so that the articles can be handled, stored and
transported safely. Normally, articles should not be stacked together while hot or wet. Long term storage in
flat contact with certain types of porous wood should be avoided.
Where there is a specific need to minimize the development of wet-storage staining, this should be
communicated by the purchaser to the galvanizer at the time of order and any relevant control measures
should be agreed.
Such measures can include, for example, storage of articles to allow free movement of air across the surfaces
of the article, 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.
[1]
In accordance with ISO 1461 the presence of wet-storage staining is not a cause for rejection, provided the
galvanized coating thickness remains above the specified minimum requirements at the time of acceptance
inspection.
6 Effect of article condition
6.1 General
Most steels and cast irons can be hot dip galvanized . This includes unalloyed carbon steels (see, e.g. EN
[4] [5] [6]
10025-2 ), fine-grained steels (see, e.g. EN 10025-3 and EN 10025-4 ), quenched and tempered steels,
[7]
hollow sections that are hot finished (see, e.g. EN 10210-1 ), hollow sections that are cold finished (see, e.g.
[8] [9] [10]
EN 10219-1 ), reinforcement steels (see, e.g. EN 10080:2005 and EN 10348 ), fastener grade steels
[11] [12]
[see, e.g. ISO 898 (all parts) ], grey cast iron (see, e.g. EN 1561 ) and malleable cast iron (see, e.g. EN
[13]
1562 ). Where other ferrous metals are to be galvanized, adequate information or samples should be
provided by the purchaser to the galvanizer for an assessment to be made whether these steels can be hot
dip galvanized. Sulfur-containing free-cutting steels are normally unsuitable. Stainless steels are unsuitable.
Most steels are not adversely affected by the heat of the hot dip galvanizing bath. For steels whose mechanical
properties may be affected by the heat of the hot dip galvanizing bath, e.g. heat treated or cold worked steels,
the purchaser should assess their suitability for galvanizing
Information on the composition and properties of steels to be galvanized may be required to be provided by
the purchaser to the galvanizer, for example when steel articles of yield strength above 460 MPa are to be
galvanized (see ISO 1461, 4.3 and A.2(a)).
6.2 Steel 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 galvanized 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 galvanized 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.
ISO/DIS 14713-2:2026(en)
Table 1 gives simplified guidance on steel compositions that are associated with certain typical galvanized
coating characteristics when galvanizing is carried out at temperatures of 440 °C to 460 °C.
Table 1 — Galvanized coating characteristics related to steel composition
Category Typical levels of reactive Additional information Typical galvanized coating
elements characteristics
% (mass fraction)
A ≤ 0,03 % Si and < 0,02 % P See NOTE 1 and NOTE 4 Galvanized coating has a shiny
appearance with a finer texture.
Galvanized coating structure
includes outer zinc layer.
B ≥ 0,14 % Si to ≤ 0,25 % Si Other elements can also affect Galvanized coating can have
steel reactivity. In particular, shiny or matt appearance. Gal-
phosphorus levels greater than vanized coating structure can
0,035 % will give increased reac- include outer zinc layer or zinc-
tivity. iron alloy can extend through to
the galvanized coating surface
depending on steel composition.
C > 0,03 % Si to < 0,14 % Si Excessively thick galvanized coat- Galvanized coating has a darker
ings can be formed. appearance with a coarser tex-
ture. Zinc-iron alloys dominate
D > 0,25 % Si Galvanized coating thickness
galvanized coating structure
increases with increasing silicon
and often extend to the gal-
content.
vanized coating surface, with
reduced resistance to handling
damage.
NOTE 1 Steels with compositions satisfying the formula Si ≤ 0,03 % and Si + 2,5P ≤ 0,09 % are also expected to exhibit these
characteristics. For cold rolled steels, these characteristics are expected to be observed when the steel composition satisfies the
formula Si + 2,5P ≤ 0,04 %.
NOTE 2 The presence of alloying elements (e.g. nickel or aluminium) in the zinc melt can have a significant effect on the
galvanized coating characteristics indicated in this table. This table does not provide relevant guidance for high-temperature
galvanizing (i.e. immersion in molten zinc at 530 °C to 560 °C).
NOTE 3 The steel compositions indicated in this table will vary under the influence of other factors (e.g. hot rolling) and the
boundaries of each range will vary accordingly.
NOTE 4 Steels with compositions < 0,01 % silicon that also have aluminium contents > 0,035 % can exhibit lower reactivity
that could result in a lower than expected galvanized coating thickness. These steels can exhibit reduced levels of galvanized
[1]
coating cohesion. See ISO 1461 .
NOTE 5 The design of the article to be galvanized can also influence galvanized coating characteristics.
6.3 Castings
Castings should be as free as possible from surface porosity and shrinkage holes and should be cleaned
by grit blasting, electrolytic pickling or by other methods especially suitable for castings. Conventional
hydrochloric acid pickling does not remove mould-sand deposits, graphite or temper carbon from the surface
of cast iron. Grit blasting is necessary to remove these contaminants. Surface cleaning of complex shapes can
be undertaken by specialist galvanizing companies using hydrofluoric acid. Care needs to be exercised in the
design of cast iron sections. Small castings of simple shape and solid cross-section do not present problems
for galvanizing, provided that the material and surface condition are suitable. Larger castings should have
a balanced design with uniform section thicknesses to avoid distortion and cracking due to thermal stress.
Large fillet radii and pattern numbers should be used and sharp corners and deep recesses avoided.
The rough surface finish that castings tend to possess can result in thicker galvanized coatings than on
rolled articles.
Graphite exposed at the surface of iron castings interferes with wetting by molten metal and those castings
that have been annealed can have silica partic
...