If you’re a metalworker, you’re probably familiar with the process of galvanizing. It’s a simple way to protect metal surfaces from rust (corrosion) and wear and tear. In fact, the first patent for the process of galvanising was taken out in 1836 so it has been around for quite some time. In mid-nineteen century Britain, sheets of galvanised corrugated iron were seen to be exciting and glamorous. The concept of adding rigidity to iron sheets not only allowed for the construction of wide-span roofs without the need for cumbersome load bearing walls but they also looked new in an environment dominated by stone and timber. The silvery reflective material was a sign of progress and success of industry. At KidZplay, we love seeing the shiny truckloads of equipment arrive back from the galvanising firm we use. All our rental equipment is put through this process because we are all about long term sustainability.
But what is galvanising, exactly?
Galvanising is a process that involves coating a metal surface with a protective layer of zinc. This layer of zinc helps to protect the metal from corrosion, rust, and other damage caused by water, air, and other environmental factors. It’s a great way to extend the life of metal components and make them more durable over time. Some of our rental jungle gym stock is over 20 years old and once given a fresh coat of paint, looks brand new!
At KidZplay, we use the process of Hot-dip galvanising for our gyms.
The hot-dip galvanising process starts by cleaning the metal surface. This is done using a chemical solution that removes any dirt and debris from the surface. Once the surface is clean, it is then submerged in a bath of molten zinc at approximately 450°C. As the zinc cools and hardens, it forms a protective layer around the metal. This layer of zinc helps to protect the metal from corrosion, rust, and other damage caused by water, air, and other environmental factors. It is vital, especially in coastal areas as well as where it is misty or experiences snow.
The galvanising process can be used on a variety of metals (including steel, aluminium, copper, and brass). It‘s an ideal choice for protecting Jungle Gyms that are exposed to harsh weather conditions or moisture. One of the most important things to consider when it comes to galvanising is the thickness of the zinc layer. The thicker the layer, the better the protection against corrosion and wear and tear. According to UK Galvanizers Association, an average coating thickness of 85 microns (the same thickness as a sheet of A4 paper) can protect a steel structure for the better part of 100 years!
The galvanising process is relatively quick and easy to complete. Once the metal component has been submerged in the zinc bath, it is then allowed to cool and harden. This process usually takes just a few minutes. After the component has cooled and hardened, it can then be removed from the bath and inspected for any flaws or imperfections.
You may also hear the term cold galvanising. This is the application of a paint-like (zinc-rich) coating to steel. The difference between the two types of galvanising is that Hot dip galvanising is a chemical treatment in which an where an electrochemical reaction takes place, whereas with cold galvanisation, a physical treatment takes place in which a layer of zinc just gets brushed on the base metal. Because cold galvanizing is simply a coating, it cannot bond with the metal on a chemical level and, as such, does not have the same durability, abrasion resistance and protection capabilities as hot-dip galvanizing. At KidZplay, we have therefore chosen to use the Hot-dip method.
To summarise, galvanizing protects from rust in a number of ways:
1. It forms a barrier that prevents corrosive substances from reaching the underlying steel.
2. The zinc serves as a sacrificial anode so that even if the coating is scratched, the exposed steel will still be protected by the remaining zinc.
3. The zinc protects its base metal by corroding before the steel.
4. The zinc surface reacts with the atmosphere to form a compact, adherent patina that is insoluble in rainwater.
Galvanising is an effective way to extend the life of Jungle Gyms and make them more durable over time. If you’re looking for an easy way to protect your playground equipment, galvanising is the perfect solution.