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ISO 1461 – which is the British standard for hot dip galvanized coatings on iron and steel articles – has recently been updated. The new version was released in August 2022 and supersedes the 2009 version.
The standard will be adopted by CEN (the European Standards Organization) and subsequently by National Standards Bodies, including BSI in UK and the National Standards Authority of Ireland.
Several important changes have been made to the document. As the changes affect both us and you – our customers – we’ve listed them below:
Summary of Major Changes
The most significant changes to the document concern the galvanizing of ultra-low reactive steels, coating thickness measurements on ancillary elements, removal of flux residues and zinc ash, and the renovation of galvanized steelwork.
There has been no fundamental change to the method of assessment of coating thickness, but allowances for measurements on ancillary elements and ultra-low reactive steels have been introduced. The revised standard states that thickness measurements should not be taken on ancillary elements (e.g. brackets) unless specifically requested by the customer. Recognition that certain steel compositions can exhibit ultra-low reactivity during galvanizing (i.e., cannot satisfy the standard minimum coating thickness requirements) has been introduced. Articles produced from steel with a section thickness greater than 3mm which have a composition of ≤0.01 % silicon AND an aluminium content >0.035 %, that exhibit ultra-low reactivity during galvanizing, can now be subject to lower coating thickness requirements (see 6.5 below). The variation to the standard requirements must be included in the Declaration of Compliance if one is to be provided.
An important change has been made with regards to removal of flux residues. In the 2009 version, flux staining/residues were not permitted anywhere on the article, but the updated version now acknowledges that removal (including zinc ash) in some fabrications is practically impossible. Therefore, if ‘access is restricted, for example inside hollow sections’ flux residues and zinc ash are permissible.
The key changes to the content on renovation of galvanized steelwork are the requirement for the pigment in a zinc-rich paint to conform to ISO 3549 ‘Zinc dust pigments for paints — Specifications and test methods’ which has been removed but must still offer sacrificial protection to the steel; and also, more comprehensive information within Annex C – Renovation of uncoated or damaged areas.
Changes in ISO 1461:2022 vs 2009 edition
1 Scope – No significant changes were made to the scope, however clarification to clearly state the standard specifies the general properties of, and test methods for, ‘hot dip galvanized’ coatings were incorporated.
2 Normative references – There has been slight changes to the standards contained within the normative references to reflect their status within the document. Notably, ISO 14713-2 ‘Zinc coatings — Guidelines and recommendations for the protection against corrosion of iron and steel in structures — Part 2: Hot dip galvanizing’ has been included.
3 Terms and definitions – Five new terms, galvanizer (3.3), after-treatment (3.18), additional coating (3.19), wet storage stain (3.20), duplex system (3.21) have been introduced to allow for simplification of the main text.
4 General Requirements – No significant changes.
5 Acceptance inspection and sampling – No significant changes, except the minimum number of articles in a control sample can be subject to deviation following agreement within the supply chain. The new text now reads ‘Unless otherwise agreed, the minimum number of articles from each inspection lot that forms the control sample shall be in accordance with Table 1.’
6.1 Galvanized coating properties – Appearance – Clarification has been made that only the visible significant surfaces are subject to the appearance acceptance inspection. Flux residues and zinc ash shall be removed where they can affect the intended use of the HDG article, or its corrosion resistance requirement, unless access is restricted, for example inside hollow sections. Previously, flux residues were not permitted anywhere on the article.
The coating, when first examined by normal vision from a distance of not less than 1m shall be free from blisters (i.e. raised areas without solid metal beneath), roughness and sharp points (if either that roughness or sharp point can cause injury) and uncoated areas. The 2009 version also included ‘Nodules’, however this has now been omitted from the list of prohibited coating features.
6.2 Galvanized coating properties – Thickness – The greater relevance of ISO 2178 ‘Non-magnetic coatings on magnetic substrates — Measurement of coating thickness — Magnetic method’ amongst the other coating thickness measurement standards has now been acknowledged.
6.2.3 – Reference areas – now states that ‘Unless otherwise agreed, reference areas shall not be chosen from ancilliary elements, when they are significantly smaller than the main elements of a larger article’ due to being thinner or less reactive. Acceptance that flame-cutting, laser-cutting and plasma-cutting can lead to the steel being more unreactive during galvanizing and decreased cohesion of the coating has been made. The 2022 edition now reads ‘In order to obtain the required coating thicknesses more reliably and to ensure adequate cohesion or adhesion of the coating, flame-cut, laser-cut and plasma-cut surfaces should have been ground off and sharp edges should have been removed during fabrication and prior to delivery to the galvanizer.’
The minimum size of a reference area is now clearly defined as being 10cm2.
6.3 – Galvanized coating properties – Renovation – The circumstances where a lower (than 100μm) minimum repair coating thickness can be agreed, has been expanded to account for thinner galvanized coatings around the damaged area, for example, where aesthetics may be important.
6.4 – Galvanized coating properties – Adhesion – No significant changes, however a new ‘note’ has been added which recognises that cohesion of the galvanized coating can be affected by a steel being ultra-low reactive – as defined in ISO 14713-2 Table 1, Note 4. There is still not a suitable international standard for testing the adhesion of galvanized coatings.
6.5 – Galvanized coating properties – Acceptance Criteria – It is within this section where the adjustment for ultra-low reactive steels has been introduced. The new text reads:
‘For articles with steel section thicknesses greater than 3 mm, produced from steels with compositions ≤0,01 % silicon that also have aluminium contents >0,035 %, that exhibit ultra-low reactivity during galvanizing and therefore cannot satisfy the minimum galvanized coating thickness in Table 3, the next lowest category of steel article section thickness given in Column 1 of Table 3 shall be applied. In such cases, if a declaration of compliance must be provided then it shall state this variation including the adjusted minimum mean galvanized coating thickness requirement that has been applied to the inspection lot.
NOTE – Certain steels, including but not limited to, either steels suitable for laser cutting with chemical compositions as given in ISO 14713-2:2019, Table 1, Note 4 or steels with high surface smoothness, or both, can exhibit ultra-low reactivity during galvanizing (see ISO 14713-2) and the coating thickness achieved on such steel articles can possibly not be dependent on steel section thickness. These factors are beyond the control of the galvanizer and can also result in even lower coating thicknesses than given in the next lowest category of steel article section thickness given in Table 3.’
7 – Declaration of Compliance – The terminology has been modified, in ISO 1461:2009 this was referred to as a ‘Certificate of compliance’ whereas now it is called a ‘Declaration of compliance’. Clarification that this must meet the requirements of ISO 10474 ‘Steel and steel products — Inspection documents’ has been incorporated.
Annex A (normative) – Information to be supplied – An important sentence has been added to A.2– Additional information for provision by the purchaser, which states that ‘an indication of any ancillary elements within the article that must be considered as part of the significant surfaces from which reference areas might be taken (e.g. if the ancillary elements are safety critical).’ This is to account for the default procedure of not taking coating thickness measurements on ancillary components.
Annex B (normative) – Safety and process requirements – Venting and Drainage of Articles – Verification has been incorporated into this Annex that states the work presented for galvanizing should be in accordance with ‘either the guidance given in ISO 14713-2 or any further specific guidance for the articles to be processed that may arise from consultations with the galvanizer, or both.’
Annex C (informative) – Renovation of uncoated or damaged areas – Annex C contains considerably more guidance on the requirements for a zinc-containing paint used for repair than the previous version (Annex C.1 – Zinc-containing paints). See new guidance below.
‘A dry paint film that is capable of conducting electricity and which is in electrical contact with the basis metal will ensure that sacrificial protection is provided.
Other things being equal, sacrificial protection increases with increases in metallic zinc content in the dried film but does not increase further above approximately 94% by weight of zinc for paints containing zinc dust. However, other factors can be important.
A zinc-containing paint with a zinc dust content that is equal to or greater than 80% by mass in the dry film can be considered suitable for renovation of uncoated or damaged areas. Conformity of the zinc dust pigment, within a zinc-containing paint, with ISO 3549 is a further indication of suitability.
Zinc-containing paints based on lamellar shaped, rather than spherical, zinc particles may achieve adequate protection at lower contents of zinc in the dry film than for zinc dust paints with spherical particles.
Zinc-containing paints may also include an aluminium content for aesthetic purposes.’
Annex D (informative) – Determination of thickness – No significant changes.
Annex E (informative) – Corrosion resistance of galvanized coatings – Annex E has been updated to include supplementary information regarding the long-term, steady-state zinc corrosion rates given in ISO 9224 ‘Corrosion of metals and alloys — Corrosivity of atmospheres — Guiding values for the corrosivity categories.’ This is in appreciation that ISO 14713-1 ‘Zinc coatings — Guidelines and recommendations for the protection against corrosion of iron and steel in structures — Part 1: General principles of design and corrosion resistance’ provides first year exposure corrosion rate data and is therefore conservative guidance.
Further information and support
If you have any queries regarding the updated standard, please contact the Widnes Galvanising Technical Team. You can also contact GA Technical department regarding the updated standard or its interpretation. In the first instance, call their free ServiceLine on tele: +44 (0)121 355 8838 or email Dr Desmond Makepeace at d.makepeace@hdg.org.uk.
Next pageJoseph Ash Limited is delighted to announce the acquisition of Widnes Galvanising Ltd.
Founded over 20 years ago, Widnes Galvanising has been an independent hot dip galvaniser in the northwest. It is the perfect match for Joseph Ash Ltd; not only do both companies share similar values, Joseph Ash is now able to broaden its geographic coverage into Cheshire to service customers in Lancashire, Cheshire, Merseyside and beyond.
The acquisition is also good news for Widnes Galvanising customers, who will benefit from the additional services Joseph Ash Ltd provides such as extra transport, storage, spin galvanizing, and powder coating.
Existing Widnes Galvanising employees will also benefit as they will be able to capitalise on the opportunities that being part of a larger group brings, such as career progression, training, and learning new skills.
The Managing Director of Joseph Ash Ltd, said: “Widnes Galvanising is a welcome addition to our Joseph Ash family, and we are thrilled to have them onboard. The acquisition has been smooth, ensuring a seamless transition for the future. While initially trading as a subsidiary company, Widnes will share and exchange technology and expertise with our eight other plants.
“The acquisition is a wonderful opportunity for all parties involved: the existing Joseph Ash team, our new colleagues from Widnes, our suppliers and customers.”
Further announcements about the acquisition will be made in due course.
For more information, please contact the Joseph Ash Head Office on 0121 504 2573.
Joseph Ash Ltd provides hot dip galvanizing, spin galvanizing, shot blasting, powder coating and duplex coatings. As a UK leader of steel finishing services, with a long heritage dating back to 1857, the company is proud to galvanize the UK.
With nine plants across the country – serving many types of customers from large construction companies and fabricators to housebuilders, architects and developers – we’re pleased to provide the highest standards of corrosion protection available.
We also offer a one-stop-shop service from our Joseph Ash Medway plant, supplying all metal finishing treatments from a single location.
Tel: 0121 504 2573
Email: sales@josephash.co.uk
Galvanized lift innovation enables safe hoof care
Nestled amongst the rolling hills between Tregaron and Lampeter in Wales is an animal sanctuary called Beneath the Wood. Set up by Sasha Bennett in 2009, it provides a permanent home for dogs, sheep, cats, horses and – as of 2019 – a sounder of pigs.
The pigs (and their subsequent offspring) found safety at Beneath the Wood after they were rescued from an illegal and horrific slaughterhouse in Pembrokeshire. The 53 pigs were living in appalling conditions amongst carcasses and surviving on the entrails of the other slaughtered animals. Some were so desperate they began cannibalising. Some ate car parts, batteries, car doors… anything to avoid starvation.
After being rescued by authorities, the pigs became the subject of a court destruction order as they were not fit for consumption. There was a public outcry, so Beneath the Wood decided to fight for them. After a nine-month legal battle, the pigs (numbering 91 because the males were kept in a DEFRA isolation unit with the females!) were allowed to move to their forever home at the animal sanctuary.
Victory for Beneath the Wood and the pigs! But not without its problems.
Because the pigs had been kept in dreadful conditions at the slaughterhouse, their hooves had grown and, in some cases, become curved and uneven, making it difficult for them to stand and walk. As a result, the pigs needed a much-needed pedicure. But foot care on such heavy and strong animals is challenging. Especially when the biggest pig – Gandalf – is 7ft in length and weighs over half a tonne!
Beneath the Wood turned to Designeering in Leicestershire for help.
Designeering is a design and engineering company which helps people/companies to develop product ideas and bring them to life. The team at Beneath the Wood explained their problem. They told Designeering about animal lifting equipment such as cow hoists. A good idea, but unfortunately not suitable for the pigs. They needed lifting equipment that was strong and modular enough to accommodate different size pigs.
Designeering rose to the challenge and designed, engineered, and manufactured an innovative Pig Lift that can lift the pigs in the air with their feet dangling so they can be treated and trimmed.
They opted for a modular design that can accommodate animals ranging from 150 kg to over 600 kg. The unit is also mobile, electrically operated, and safe for the operator and animal.
As the Pig Lift consists of steel sections, tubes, and laser-cut sheet metal fabrication welded together to form a heavy-duty structure, it needed to be galvanized.
Hot dip galvanizing is imperative because it provides a long-life, low-maintenance corrosion protection, which safeguards the steel from atmospheric attack, which causes rust and weakens steel.
Designeering sent the Pig Lift to the Joseph Ash Group (our sister plant at Walsall) to be treated with a galvanized coating to prolong the life of the equipment. The team at Joseph Ash were delighted to help such a good cause and donated their time and service free of charge, including collection and delivery.
The Pig Lift was delivered to the animal sanctuary just before Christmas: designed, manufactured, protected from corrosion with a galvanized finish, and ready to enable hoof trimming. The giant boars need hoof trimming first, so they’re being treated, and it’s onto the other pigs.
Sébastien de La Hamayde, Creative Director at Designeering said “We’ve loved working on this project! Sasha Bennett and her team at Beneath the Woods do a fantastic job providing a safe home for all the animals they look after. As for the pigs, despite experiencing trauma at the illegal slaughterhouse where they were found, they are now well looked after and comfortable in their new surroundings. We are proud to have designed equipment to help the Sanctuary continue looking after them.”
Paul Hudson, Sales and Technical Manager at Joseph Ash, said “Wow! What an amazing project to be involved in. Thanks to Designeering for contacting us and sending the steel to our plant. We were happy to donate our services for such a worthwhile cause. We hope the pigs thrive in their new home and the new lifting equipment gives them some much-needed care.”
Beneath the Wood Sanctuary is a not-for-profit organisation. They run solely on public donations, mainly through their Twitter, Facebook, and Instagram social media accounts. They have around 140 animals in their care, ranging from dogs, cats, pigs, horses, and sheep, all rescued from difficult circumstances. They are a small team of dedicated volunteers, just five people keeping the animals fed and cared for, along with occasional volunteer days for extra help on larger projects.
To support the Beneath the Wood team, contact Sasha Bennett via email at sasha@beneaththewood.co.uk.
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