The following three European standards apply to hot-dip galvanizing. They are complementary and for this reason form an inseparable whole.
EN ISO 1461 (2022) “Coatings applied by hot-dip galvanizing to iron and steel objects – Specifications and tests.”
EN ISO 14713 (2010) “Zinc coatings” – Part 1: “Guidelines and recommendations for the protection of iron and steel in structures against corrosion” and Part 2: “Hot dip galvanizing”
EN ISO 10684 (2004; currently under revision) “ Fastener articles – Coatings applied by hot-dip galvanizing”
Apart from the above standards, there is another separate standard for pipe materials (transport pipes) that are galvanized in an automated process, the EN 10240 (1998).
EN ISO 1461 specifies the general properties of hot-dip galvanized coatings and test methods for hot-dip galvanized coatings applied by dipping fabricated iron and steel articles (including certain castings) in a zinc melt (containing not more than 2% other metals).
Every five years, in accordance with international requirements, a vote is required by all member national committees, asking whether the existing standard can be extended unchanged for five years, or whether a revision is needed. In 2019, it was concluded that a change was necessary because of the feedback gathered on the standard.
Thus, each revision is the result of comments on the content during the application of the standard. In particular, changes have been made to aspects such as appearance, layer thickness and damage repair. These modifications have created more clarity on what is or is not permissible.
Developments in the field of chemical steel compositions also gave rise to changes in the text. The description of the method of layer thickness measurements has been changed. This was not always clear, resulting in occasional discussions that were actually unnecessary.
The coating thickness table, containing the requirements of coating thicknesses linked to a particular steel section thickness, has remained unchanged. However, some comments have been added because of changing steel alloys and steel fabrications. For example, steels with a very low silicon content may not be able to meet the requirements of layer thicknesses associated with the relevant steel section thickness. In that case, the values of a lower section thickness are retained as required values.
It is also important to note that, for example, head and foot plates on longer profiles no longer need to be included in layer thickness measurements. Often such welded parts are less thick or less reactive during zinc coating.
Obtaining an optimal galvanizing result cannot and should not be separated from the design of the object and choice of material. EN 14713-2 provides information on this.
The standards series EN ISO 14713 consists of 3 parts:
Part 1 provides guidelines on the degree of corrosion resistance provided by zinc coatings when applied to iron and steel objects in various environments. These guidelines and recommendations cover aspects of importance for choosing the proper treatment method and characteristics of importance for design, material to be chosen, composition and corrosion.
Part 2 presents the general design principles applicable to products to be galvanized for corrosion protection. Herein, the influence of the condition of the item to be galvanized on the quality of galvanizing is cited, as well as the influence of the hot-dip galvanizing process on the item to be galvanized. Recommendations on transportation and storage have also found a place in the text.
This standard deals with fasteners made of steel with metric threads. These threads range from M8 to M64. The strength class applies up to 10.9 for bolts, screws and studs, and up to 12 for nuts. This standard also includes item markings and zinc coating thickness.
The following two European standards apply to duplex systems. In addition to the standards related to hot-dip galvanizing or sherardizing apply:
EN 15773 (2018) “Industrial application of organic powder coatings on hot-dip galvanized or sherardized steel (duplex systems) – Specifications, recommendations and guidelines.”
EN 13438 (2013) “Paints and varnishes – Organic powder coatings for galvanized and steel products for construction purposes.”
NEN 5254 (2003) “The industrial application of a wet paint system on hot-dip galvanized or sherardized products (duplex system).”
Code of Practice Powder and Wet Paint on Galvanized Surfaces (2021)
In addition to the above standards, there are also quality labels such as Qualisteelcoat and GSB International. Both are a type of quality assurance where a member organization records its processes and has them periodically reviewed.
This standard for powder coating systems provides requirements for all parties, which determine the quality of the final duplex system. It is important that parties are informed about design and purpose of the final product. Afterwards, it must be clear that this exchange of information took place.
This standard specifies requirements for powders to be used for duplex systems and tests for these powders.
This reworked standard with guidelines can be used for duplex systems with organic coatings other than powder coatings, being wet paint systems.
