What is Powder Coating, Hot Zinc Spray, Wet Spray and Shot Blasting?

Powder coating, hot zinc spray, wet spray and shot blasting are all methods of protecting metal products. You likely come across metals that have been affected by one or more of these processes in your day-to-day life. For example, many cars are powder coated to give them their colour and protect them from corrosion.

Here is everything you need to know about these industrial coatings, how they’re used and how they help you.

What is a Powder Coating Finish?

The Industrial coating process can involve covering a metal in a zinc primer coating. This coating contains small amounts of zinc. This zinc acts sacrificially, so rain and cold weather affect the zinc rather than affecting the metal underneath, which helps prevent it from rusting.

There is also paint powder coating. Paint powder coating used electro statically charged powder paint and when it is sprayed onto an earthed metal it is attracted and sticks. Powder coating comes in every colour you can imagine either British standard or the common scale of RAL.

What is Wet Spray?

Wet spray, also known as wet paint spraying, is the process of applying a liquid to a metal surface. This liquid is typically available in all colours and wet paint spraying is typically undertaken on large items where a skilled operator will use a spray gun.

What is Hot Zinc Spray?

Hot zinc spraying is an alternative method to hot dip galvanising. It involves coating the surface of a metal by spraying it with molten zinc. Hot dip galvanising is where metal is dipped in a bath of molten zinc rather than having the zinc sprayed on with a spray gun.

Zinc spraying is often chosen over galvanising because it gives the best finish for a smooth surface. HZS requires no fettling and is able to be applied evenly. Like all the coating methods mentioned in this article, hot zinc spraying is something we specialise in at NSP Coatings.

What is Shot Blasting?

Shot blasting is sometimes referred to as abrasive shot blasting or grit blasting. Shot blasting and grit blasting follow the same process, but grit blasting involves firing grit at a metal’s surface whereas shot blasting uses steel shot.

The shot or grit is fired at the surface of a metal to make it even and remove any paint or bumps in the metal. Grit blasting or shot blasting is typically undertaken on a metal product before hot zinc or powder coat is applied.

Which is Better, Powder Coating or Spray Painting?

There isn’t a definitive winner, it depends on your item, its size, its use and the finish you want.

What we can say is that its best to speak to an expert about your items needs and we can advise you with the best product to protect it with.