How to choose right Steel Shots / Grits for Shot Blasting Machine?

Steel shot is very important for shot blasting machine.

The working principle of the shot blasting machine is a kind of metal surface treatment technology. Steel shot or grits are thrown on work piece metal surface by centrifugal force. Linear speed can reach more than 70m/s.

Wrong steel shot selected will affect shot blasting machine performance and may also cause machine damage.

So, how to choose the right steel shots?

First of all, the type and size of the steel shot should be based on the work pieces to be cleaned:

Nonferrous metals generally use aluminum shots or stainless steel shots;

Ordinary steels, castings, and fabricated jobs use carbon steel shots or grits. S290 and S330 are mostly used.

 Silica sands, plastics, glass and ceramic abrasives can be used on shot blasting machine.

Secondly, steel shot with larger diameter will get rougher surface. And cleaning efficiency is also higher.

Irregular-shaped steel abrasives like steel grits, cut wire also have rougher surface higher efficiency than round steel shots. But irregular-shaped steel abrasives wear the equipment relatively quickly. Anyway this additional wear can be accepted considering efficiency at some specific condition.

Finally, hardness is proportional to the cleaning speed, but inversely proportional to consumable part life. It means that the hardness is higher, the cleaning speed is faster, but consumable part life is shorter, and the cost will increase. Hardness should be moderate . Mesblate recommends HRC40-50 . At this hardness, balance is achieved among moderate hardness and excellent resilience, and reduced processing time.