The Galvanizing Process at Forfar is like that of none other, each step of the galvanising process is meticulously controlled by experienced and highly skilled supervisors and operatives. Applying the hot dip galvanizing process to steelwork provides products with a robust, durable and corrosion protective finish that will last for many years without maintenance of any sort. The process itself has a number of stages that are required to achieve the galvanised finish.
Forfar Galvanisers are able to omit 2 stages of the traditional galvanising process due to the advanced technolgy in our plant.
This makes the whole process more time efficient and making the experience smoother for the customer.
- Degreasing - The process of producing a surface which is not contaminated with oil, or grease based products. This may be carried out by coating the ungalvanising products with either an acid or alkaline based proprietory product.
- Rinse - This stage of the Galvanizing process can be omitted within the Forfar plant, making the whole galvanizing process smoother and time efficient.
- HCl - Or the Pickling process as it is also sometimes known consists of the product being dipped in Hydrochloric acid or sulfuric acid to remove oxidation (rust) from the metal surface, making the surface clean and able to react with the molten zinc.
- Rinse - This part of the process is vital to the Galvanizing process as the rinse removes and possibility of contamination in the next chemical bath.
- Flux - This may be done by dipping the work in a solution of zinc ammonium chloride, or by using a layer of this chemical which floats on the surface of the molten zinc bath. This is normally used at between 50C and 70C, which helps the steelwork to dry after it is withdrawn. Drying is important as it helps prevent zinc splash and a separate drying stage is sometimes employed.
- Dry - The second process that does not need to be carried out due to the advances in technology within the Forfar plant.
- Zinc - Finally, the prepared article is dipped into a bath of molten zinc which is kept at a temperature of approximately 450°C. The clean steel is immersed in the zinc and while it is submerged it alloys with the iron in the steel to form zinc/iron alloy layers. These layers form the basis of the coating, which is then covered with free zinc, as it is withdrawn from the galvanizing bath.
- Water - After dipping, the product is cooled by quenching in water, inspected for defects, and stored until ready for collection or delivery by our very own fleet of vehicles.
When the reaction between iron and zinc has virtually ceased and the article is taken out of the galvanizing bath complete with its outer coating of free zinc, the process is complete. In reality there is no demarcation between steel and zinc but a gradual transition through the series of alloy layers which provide the metallurgical bond.
Shotblasting and Powder Coating can be arranged by request.