How to Choose Abrasive Blasting Nozzle Size

As an essential component of the blasting equipment, the abrasive blasting nozzle has a direct influence on how economical and efficient your work is. So selecting a suitable blast nozzle is an important step before you start the abrasive blasting working.

Selecting the right nozzle often starts with the air compressor. Once you understand how the size of your compressor affects production capabilities, then you will want to look at nozzle size.

When we talk about the nozzle size, generally it is referred to as the nozzle bore size (Ø), which is also called the path inside of the nozzle. Choose a nozzle with too small of a bore and you will be leaving some blasting capacity on the table. Too big of a bore and you will lack the pressure to blast productively. 

The most commonly-used nozzle bore sizes range from 1/8" inner diameter to 3/4", increasing by increments of 1/16".

Nozzle selection depends on the size of the blast pattern you are looking for. If you are blasting large sheets of metal and require a larger blast pattern, a 3/8”(9.5mm) -1/2”(12.7mm) nozzle will suit your application. However, if you are blasting steel structures and require a smaller blast pattern then it is recommended a 1/4”(6.4mm)– 3/8” (7.9mm) nozzle. In addition to the area to be blasted, the choice of the nozzle bore size must also be based on the compressed air available from the compressor. Depending on the available air, it is better to use the largest nozzle possible to achieve the greatest possible coverage at the same time. This is vital for economical work in terms of blast media costs, compressor costs, labor costs, and costs for set-up time.

The chart below shows the correlation between the nozzle bore size, the volume of air, and nozzle pressure which are often used in the industry, which will give you guidance to select a suitable nozzle bore size and maximize your blasting job.

Attention: It is important that when you double the diameter of the bore, you quadruple the size of the bore and the volume of air and abrasive that can pass through the nozzle.

Besides, you also need to consider the abrasion of nozzles. Over time due to wear, the nozzle diameter will increase, which also then requires more compressed air at the same time. Therefore, the user should inspect the nozzle diameter regularly (e.g. with a drill bit with the appropriate diameter) and the nozzle should be replaced if necessary. If this is not done, the compressor may not produce the required power, and the nozzle will lose its effectiveness. 

BSTEC provides a wide variety of abrasive blasting nozzles, welcome to contact us for more details.