In spraying one can distinguish between the air atomization(pneumatic spraying) and the airless (hydraulic spraying) processes.In the atomization process, distinction is based on thepressure used: low-pressure (0.7 bar, HVLP), medium pressure(1.3 bar, HVLPplus) and conventional (high-pressure air atomizationat 4 to 6 bar). The painting process starts with choosingthe appropriate material and placing it in the material container.From that point it is moved to the material nozzle in thespray gun. Locatedalongtheroute taken by the material is the material needle valve; it regulates the flow of material. Theatomization air flows around the material as it exits the nozzleand divides it into miniature droplets. The spray jet is created.
The source of energy for atomization is the pressurized airwhich enters the pistol through the air connector. The amountof air is controlled by the air volume regulator while the widthof the spray jet is controlled at the round and broad spray regulator.The spray gun is now ready for use. To initiate atomization,the trigger is first retracted slightly. Thus the air valve(poppet valve) built into the air regulation system is opened.The path for the air is now free (preparatory air flow). When thetrigger is pulled further, the material needle valve retracts fromthe material nozzle. The path for the material is also free.
Matching the pattern of the spray jet to the object beingpainted is handled with infinite regulation between round andbroad spray. The application speed will have to be matchedto the spray width. When the round/broad spray regulator isopened, pressurized air is passed through the two horns on theair cap; this air widens the round spray. This regulating screwis closed when the round spray pattern is desired. Additionalparameters (material quantity) can be determined by selectingthe nozzle size.