Pros and Cons of Wet Blasting

Wet blasting involves mixing a dry abrasive with water, it is an industrial process in which pressurized wet slurry is applied to a surface for various cleaning or finishing effects. Though it is popular nowadays, there are still different voices for wet blasting. In this article, let us get to know the Pros and Cons of Wet Blasting.

Pros of Wet Blasting

1.     Dust Reduction

 It is the key advantage of wet blasting. Due to the use of water, wet blasting reduces the amount of dust produced by the abrasive blasting process, therefore no dust collectors or extra environmental precautions are required. It protects the operative, adjacent working parties and any dust sensitive plant from fine, abrasive, airborne particulates and this has huge advantage in open environments.

2.     Reduce media consumption

The presence of water means that there is more mass at the point of impact. This means that you may require less abrasive. When you switch from dry blasting to the wet blasting, you can see an immediate savings in media consumption and may save by 50% or more.

3.     Deep surface cleaning

Some types of wet blasting provides deep surface cleaning by removing and immediately washing away any dirt and contaminants adhering to the work pieces. You can strip the surface and clean it at the same time. This negates the need for a separate rinsing process to remove media fragments and soluble salts.

4.     No fire/explosion risk

Abrasive blasting can cause sparking, which can cause fire/explosion where flammable gasses or materials are present. Wet blasting does not completely remove sparks, but does create ‘cold’ sparks, essentially removing the static and thus reducing the risk of explosion during operation.

5.     Exceptionally fine, uniform finishes

In wet blasting, the water cushions the impact of the media, leaving only slight or no deformation on the surface of the work piece. This produces a lower surface roughness than dry blasting without jeopardizing the overall cleaning effect.

6.     Save space and create a more efficient workflow

With no dust, no chemical exposure and low noise, the wet blasting systems can be placed near sensitive equipment and environments.

Cons of Wet Blasting

1.     Water Consumption

A level of valuable water resource is consumed during the process, even more so depending on which method of Wet Blasting is used.

2.     Water Mist reduced visibility

Although visibility can be increased due to the lack of airborne dust, visibility is still reduced somewhat due to the presence of return spray mist from the water.

3.     Wet Waste

The water has to go somewhere. And so does the wet abrasives. This waste can be heavier and much more difficult to remove than its dry equivalent.

4.     Higher Costs 

Water pumping, mixing and reclamation systems, plus the requirement for containment and drainage can increase the costs of wet blasting and the amount of equipment required.

5.     Flash Rusting 

Exposure to water and oxygen increases the speed at which a metal surface will corrode. To avoid this, the surface must be quickly and sufficiently air dried afterwards. Alternatively a rust inhibitor can be used to ‘hold’ the blasted surface from flash rusting, but is not always recommended and the surface is still required to be dried before painting.

Final Thoughts

If you want to obtain perfect finishing results and need to significantly protect an open environment or adjacent dust sensitive plant, then wet blasting is a good choice for you. However, most other applications where the adequate environmental controls, containment and equipment are more than suitable for dry abrasive blasting.