Wet sandblasting


Sandblasting is a technique widely used in industry for cleaning, preparing and restoring surfaces. Among the various methodologies available, wet blasting has gained increasing popularity due to its effectiveness and the many advantages it offers over other techniques.

Wet blasting is a technique that involves using an abrasive, usually sand or grit, mixed with water to create a mixture which is blasted at high speed onto the surface to be treated. This process is done through a device called wet sandblaster, which sprays the wet abrasive using compressed air.

The wet sandblaster consists of:

  • Abrasive tank: A special tank holds the abrasive, usually sand or grit. It can be of variable size depending on the needs of the application. The abrasive is supplied to the mixing chamber through a controlled feed system.
  • Water Tank: Water is introduced into the system to create the abrasive mix. The amount of water can be adjusted according to the specific needs of the job.
  • Mix Chamber: This is where the abrasive and water combine to form the wet mix. This chamber is designed to ensure adequate and homogeneous mixing of the two components. The abrasive and water are mixed together to form a slurry that can be projected onto the surface.
  • Feed system: It is responsible for supplying the abrasive from the sandblaster to the point of projection. There are several types of feed systems, including gravity feed systems or compressed air systems that push the abrasive through a tube into the mixing chamber.
  • Projection nozzle: The projection nozzle is the part from which the mixture of abrasive and water is expelled towards the surface to be treated. The nozzle is designed to allow for precise adjustment of mixture flow and spray angle. This allows the process to be adapted to the specific needs of the application.
  • Air compressor: it is required to generate the pressure necessary to project the mixture onto the surface to be treated.
  • Controls and Adjustments: A wet sandblaster has controls and adjustments that allow you to manage the flow of abrasive and water, air pressure and other parameters. These controls can include control valves, gauges and switches to allow for precise control of the process.

The exact configuration and components of a wet sandblaster can vary by manufacturer and specific model. However, the basic principles and functionality generally remain the same, allowing for effective and controlled cleaning of surfaces. Wet sandblasting, just like the traditional one, can also take place inside special chambers, suitable for operating on small-medium sized items.

The benefits of wet blasting

Less dust production: One of the main problems of traditional sandblasting is the generation of large quantities of dust in the air during the process, which is particularly harmful for operators (especially due to the presence of silica). Wet blasting significantly reduces dust generation, making the working environment safer and improving air quality.

Less damage to surfaces: Unlike dry sandblasting, wet sandblasting is less aggressive towards the treated surfaces. The water present in the mixture reduces the direct impact of abrasives on the material, minimizing damage such as scratches or unwanted marks.

Greater control: The presence of water in the wet blasting process allows for greater control over the speed and intensity of the abrasion. This allows you to precisely adjust the pressure and quantity of abrasive used, adapting the technique to the specific cleaning and surface preparation needs.

Effective Contamination Removal: The combination of abrasive and water in wet blasting offers greater effectiveness in removing contaminants such as oxides, rust, paint, coatings, dirt and material residues. Wet mix penetrates surface irregularities better, cleaning them more thoroughly than dry blasting.

Applications of wet blasting

Wet sandblasting finds various applications in various industrial sectors, including:

Metal surface restoration: It is widely used in the restoration of metal surfaces, such as bridges, tanks, ships and machinery components. Effectively removes rust, old paint and coatings, preparing surfaces for new finishes or protective applications.

Cleaning of stone and concrete surfaces: widely used for cleaning and restoring stone, marble and concrete surfaces. Removes stains, efflorescence and material residues, restoring a clean and uniform appearance to the surface.

Graffiti Removal: Offers an effective option for removing graffiti from surfaces such as walls, monuments and building facades. The combination of abrasive and water allows you to completely remove unwanted paint marks without damaging the underlying surface.

Wet sandblasting chamber
Wet sandblasting chamber