Description of the wet blast process


The machine sump is filled with a mixture of water and blasting medium.

Depending on the machine size and type normally 40 – 60 kg of blast media are filled in.
This mixture is transported via our own developped, extremely wear resistant wet blast pump via rigid and thick walled pipes and tubes to the blast guns.

A bypass whirling up nozzle, which is installed in the lower sump unit, ensures that the blast media is whirled up immediately (with the starting of the blast pump) and is always available in the necessary concentration level.

For most applications compressed air is being added at the blast guns, which accelerates the blast media / water mixture.

The compressed air is adjusted either via a manual or via an electronical pressure regulator. Therefore the control of the correct air pressure is easy und precise.

Also with different air pressure, different results can be achieved. The wet blast jet hits the workpiece and flows back into the sump. This results in a continuous high volume circulation. At the back of the machine there is an overflow to the filter tank, which is also installed at the back. So the dirt and grease, which is cleaned from the workpieces or moulds is separated and processed in this filter unit.

There, dirt is being collected by a filter sac. The filtered water is then pumped back into the cabinet via a robust air dipahragm rinse pump. This is necessary to use the cleaned water for rinsing the blasted tools, in a closed loop.

The wet-blasting machines of Graf Technik can be used for different tasks:

Depending of the choice of blast media and its size, workpieces, moulds and parts can be cleaned, activated, edge honed, deburred, descaled, degreased or polished.