Shot blasting

No other process is more suited to removing undesired layers or coatings.

About shot blasting

There are times when material comes in for hot dip galvanizing that is contaminated with paint or grease. If the contaminants are not removed prior to galvanizing they will prevent the steel being pickled by the acid. And if material isn’t acid pickled correctly then hot dip galvanizing will not take place. The only way to remove contaminants prior to galvanizing is to shot blast the material. 

Shot blasting is also essential when trying to achieve a thicker galvanized coating. The British standard for hot dip galvanizing (BS EN ISO 1461) states that if 140microns is required, the material should be shot blasted to sa2.5 using chilled iron grit.

When shot blasting with chilled iron grit, the steel becomes keyed, which helps the zinc adhere to the steel. Chilled iron grit is a better option than bead blasting as it creates a better key and a rougher surface.

Once steel has been shot blasted, it is important to hot dip galvanize it as soon as possible afterwards, to maximise its effect on coating thickness.

Whilst we do not provide shot blasting from our Hull or Corby plants, we can arrange for your steel to be collected for galvanizing direct from the shot blaster.

For an additional transport cost we can also collect from the customer, deliver to the shot blaster, and re-collect once shot blasted to be galvanized and delivered back to the customer.

Alternatively, our sister site in Medway – Joseph Ash Medway – is our one-stop shop location for shot blasting, galvanizing, and powder coating, all under one roof. As part of the Joseph Ash Group, you can expect the same great quality without waiting for multiple service providers.