The A-Z of Galvanizing

Welcome to Galvanizing Today's A-Z of Galvanizing – everything you’ve ever wanted to know about galvanizing if you work with steel.

A for Acid

Pre-treating steel to ensure it is free from surface contaminants is a fundamental part of the hot dip galvanizing process, as the zinc in the galvanizing bath will not react to unclean metal. As part of the pre-treatment stage, steel is pickled in acid to remove mill scale and rust, producing a chemically clean surface suitable for galvanizing.

B for Bath Sizes

Different bath sizes suit varied steel fabrications, from the smallest to the largest of jobs.

Joseph Ash Galvanizing owns both the widest and the deepest galvanizing kettles in the UK, at Telford and Bilston respectively.

C for Circular Economy

A circular economy encourages materials to be remade and recycled, rather than throwing them away after use. Hot dip galvanizing fits perfectly into a circular economy because it optimises the durability of steel and facilitates the ease of reuse. It can also be recycled if there’s no immediate need to repurpose it. This makes hot dip galvanizing a sustainable choice.

D for Design

Good steel design helps prevent any processing problems at the galvanizing plant and ensure the best steel coating possible. Designing steel for galvanizing also includes creating adequate vent holes to ensure it remains safe for the process, avoiding a chemical reaction of super-heated steam. More on this can be found in V- Venting.

If in doubt, always contact your galvanizer's Technical Support Team for help. We also have several resources to assist you with the design process, including our Safe Design for Hot Dip Galvanizing guide. It's always best to ask beforehand if you're not sure.

E for Environment

At Joseph Ash Galvanizing we are committed to preventing pollution and minimising environmental impacts. For every process of our operations, we take a proactive approach to controlling emissions and ensuring the highest protection for the environment.

You can follow how we do this in Our Green Future – a fun, interactive graphic showing all our service steps, from collecting steelwork from a customer to its delivery at the end destination, and all our environmental processes along the way.

F for Fettling

Once steel has been hot dip galvanized, a small amount of surface finishing may be required to smooth, clean or condition the metal. This is known as fettling.

G for Galvanizers Association

The Galvanizers Association has been providing free, authoritative advice on hot dip galvanizing since 1949. Visit their website for a wealth of steel and coatings information.

H for Health and Safety

The health and safety of our people is of the utmost importance at Joseph Ash Galvanizing, and we have committed to ensuring our plants are safe environments to work and visit. This includes regular personal and atmospheric checks to ensure that our teams are operating in conditions below workplace exposure limits.

I for ISO Standards

ISO standards dictate ways of doing things, whether making a product or providing a service. They are the distilled wisdom of people with expertise in their subject matter.

There are many different standards that Joseph Ash Galvanizing complies with to ensure we provide the best service and product for our customers. Examples include the Coatings Requirements of BS EN ISO 1461, the Quality Management System of ISO 9001, and the Environmental Management System of ISO 14001.

J for Jigging

A jig holds steel in place in the correct orientation throughout the galvanizing process. This is usually done with hooks or wires.

K for Kettle

Galvanizing baths are also known as galvanizing kettles. They are large rectangular structures made from steel plates welded together, and they come in many sizes.

Galvanizing kettles are filled with zinc, which becomes a liquid state when heated around 450°C. Steel that needs to be galvanized is lowered into a kettle at an angle so that the zinc can coat the steel and the excess zinc can run off it.

L for Lifespan

Steel is a tough, durable metal; it can last for decades when appropriately treated, such as through hot dip galvanizing. The total potential lifespan of galvanized steel depends on the environment and the thickness of the galvanized finish. Galvanized steel has a much longer lifespan than painted or ungalvanized steel.

M for Microns

A micron is equal to one thousandth of a millimetre. To be ISO compliant, the galvanized finish should be a minimum of 85 microns thick but in reality hot dip galvanizing produces much thicker coatings than this.

N for Non-ferrous Metals

A non-ferrous metal is one that does not contain iron in significant amounts. Zinc, which is used in the galvanizing bath, is an example of a non-ferrous metal.

The reason why steel can be hot dip galvanized is because it is a ferrous metal. Non-ferrous metals such as brass, copper and aluminium are not suitable for hot dip galvanizing because iron is needed for the process to happen.

O for Operatives

Hot dip galvanizing is a chemical process, carried out by highly skilled operatives. At Joseph Ash Galvanizing, many of our valued colleagues have been honing their skills over periods of 20, 30 and 40 years, which means your steel is in safe hands.

P for Powder Coating

Powder coating is a paint mainly applied to metals to provide a more durable finish than traditional liquid paint. The paint is applied as a powder electrostatically from a spray gun and is cured in an oven under high heat to form a tough, durable skin. Powder coating paints come in many colours and can be used to create different finishes, such as textured or metallic.

When used in conjunction with hot dip galvanizing, an incredibly durable finish known as a duplex coating is made.

Joseph Ash Medway is the ideal place for powder coating your steel, being among only a handful of approved AkzoNobel paint applicators.

Q for Quenching

Quenching is the process where steel is rapidly cooled after it has been lifted from the galvanizing bath by immersion in water and/or a dilute chromate or phosphate solution.

R for Rust

Steel is made from iron, which rusts when exposed to water and oxygen. To prevent rust from forming, hot dip galvanizing coats steel in zinc. The zinc reacts with oxygen and carbon dioxide to form zinc carbonate. This becomes a protective barrier, stopping water and oxygen from reaching the steel.

S for Spin Galvanizing

Small items such as nails, chains, nuts, bolts and screws need to be as rust resistant as the steel structures they support. However, they are too small to galvanize in a hot dip galvanizing bath. With spin galvanizing, small items can be placed in a perforated basket and immersed in molten zinc. Once the zinc/alloy layers form, the basket is centrifuged at high speed so that the spinning action removes the excess zinc and creates a clean profile.

Our specialist spin galvanizing facility can be found at Joseph Ash Telford.

T for Transport

Wherever you are, or wherever the end destination for your fabrications is, Joseph Ash can transport them for you using our large fleet of specially equipped lorries.

The ability to collect and deliver steel is vital as we like to make life as easy as possible for customers.

U for Ultrasounds

Galvanizing baths are necessary for the galvanizing process to protect steel from corrosion. But galvanizing baths need protection, too, so they can continue to be used for galvanizing. Non-destructive testing is used for this purpose.

The testing involves ultrasounds which determine the thickness of a bath over time. If the bath becomes too thin, it could crack. Not only would this put the bath out of action for many months, but it would also be perilous for colleagues if molten zinc leaked onto the floor of the plant.

V for Venting

To achieve the best quality zinc coating, it is important to ensure that the molten zinc can flow freely over all surfaces, externally and internally. So, where there are sealed hollow sections or cavities, vent and drain holes are essential.

Our educational YouTube series shows different examples of what can go wrong when inadequately venting various steel fabrications.

W for Waste

Plants at Joseph Ash Galvanizing galvanizing plants are self-contained, with steel going in at one end and the final product coming out at the other. This means we can control the amount of waste we produce.

Our interactive animation shows how we aim to capture waste at all stages of the galvanizing process.

X for Xtra Services

At Joseph Ash, we want to make our customers’ lives easier. We do this by providing a range of additional services which aim to make the process as seamless as possible for all involved.

These include collection and delivery options; bundling, packing and labelling of steel; on-site storage facilities; and full technical support at every stage of the process.

Y for You – Our Customers

There's a reason we've been trusted to galvanize steel for over 165 years - longer than any other UK galvanizing company. We hear your requests and treat your steel according to your needs. Whether you need hot dip galvanizing at a certain level of microns, or a duplex coating with a particular colour and finish, we will help.

We also conduct monthly customer surveys to gather feedback on our performance, which we take on board and use to further better our services.

Z for Zinc

Last, but certainly not least; molten zinc is the primary material in hot dip galvanizing. Zinc is a chemical element with the symbol Zn and atomic number 30. It is found in mineral deposits along with other base metals, such as copper and lead.

The galvanizing process coats steel in zinc, which acts as a protective barrier against water, the leading cause of rust. The zinc in a galvanizing bath is molten at 450°C. Once the steel has reached this temperature, it is ready to be lifted from the bath.

Has our A-Z of galvanizing been insightful? Let us know in the comments.