Spray equipment
The following solutions are distinguished in spraying devices:
1. Manual spray pump: the necessary air pressure is generated by means of a hand pump, and the spray pressure is 5-20 bars.
2. Spray nozzle: the spray pressure is generated by the propellant; it amounts to 3-4 bars (1 bar = 0,1 MPa).
3. Urządzenie natryskowe niskociśnieniowe: the necessary air pressure is generated by a blower with a paddle blade (vacuum cleaner principle). The spray pressure is 0,2-1 only.
4. Urządzenie natryskowe wysokociśnieniowe: in this solution, the required air pressure is achieved using a compressor; normally the spray pressure is within the range 1 + 6 bars.
5. Urządzenie do ciśnieniowego natrysku materiału (typu Air-less): fluid pressure is achieved using a diaphragm or pneumatic piston pump; the spray pressure is 110-220 bars.
6. Urządzenie do ciśnieniowego natrysku materiału będącego pod ciśnieniem. It is a spray device, wherein the pressurized fluid is additionally atomized with compressed air. The necessary pressure is obtained using a compressor and a pneumatic piston pump. The pressure of the liquid is 40-50 bars, and the air pressure is approx. 1 only.
The hand-held spray pumps are suitable for the application of lime paints, silicate, impregnating agents and wood preservatives (you must wear a respiratory mask).
Low pressure sprayers are quite comfortable to use. With such a spray, less fog is formed, than with high-pressure spraying, while the performance of the device is very limited. Low pressure spraying is mainly suitable for painting small areas. Multi-purpose varnishes must be sprayed using a low pressure device and this is one of the most important applications of this type of spraying.
When the air is compressed, water vapor condenses in the compressor and in the air line. Otherwise, residual oil may appear in the air tube. Oil and condensate residues create bubbles and craters in the paintwork. Oil and condensate separators can prevent these defects from occurring. These devices should be mounted as close as possible to the spray gun.
It is also recommended to add oil and condensate to the main separator, Additionally, a smaller condensate separator directly on the spray gun.
In high-pressure spraying, there are three ways to supply the spray material:
1) przez pistolet z pojemnikiem przepływowym,
2) przez pistolet z pojemnikiem do zasysania,
3) przez zbiornik ciśnieniowy na pistolecie ciśnieniowym.
The nozzle size for a gun with a flow-through reservoir should be 1,2 the 1,5 mm.