Spray painting is the process of atomising a stream of paint into tiny droplets and these atomised droplets of paint travel from the spray painting equipment to the surfaces being spray painted..
Traditionally one of the most common spray painting equipment types is the conventional air spray gun which uses compressed air from an air compressor. This compressed air travels through the conventional air spray gun and is directed against the stream of paint exiting the spray gun fluid nozzle to break this stream up into tiny droplets and blow these droplets away from the spray gun towards the surface being spray painted. In these types of air spray guns paint may be delivered to the fluid nozzle by way of a siphoning effect caused by the compressed air flowing through the spray gun, or by gravity affect where the paint reservoir is mounted above the spray gun fluid nozzle or by pressure delivery of the paint from a pump or pressure displacement pot.
Typically HVLP, high volume low pressure and LVLP, low volume low pressure operate on the same principles as conventional air spray guns with the main difference being differences in the ratios of compressed air pressure, compressed air volume and paint fluid delivery which in the correct ratios can often increase paint transfer efficiency meaning more of the atomised paint is deposited onto the intended surface rather than being lost in the atmosphere is over spray.
Airless spray painting operates on the principle of paint being forced through a very small orifice shaped like an acute ellipse with the corners cut at varying angles to widen or narrow the spray fan pattern. Paint being forced through an airless spray tip by a airless spray pump is atomised as it hits the atmosphere and the introduced velocity carriers the atomised paint droplets through the atmosphere onto the surface.
Air assisted airless spray painting is a hybrid combining air spray and airless spray to achieve faster production rates, often higher atomisation of heavier coatings and generally higher transfer efficiencies. Electrostatic spray painting is where atomised droplets of paint are electrically charged and the object to be painted is negatively grounded so the atomised particles of paint are attracted to the grounded object.
Electrostatic spray painting systems are available for dry powder application or wet coating application. Wet electrostatic spray painting systems are available as conventional air spray, high-volume low-pressure, HVLP, or even airless and air assisted airless spray electrostatic spray painting systems.