HVLP (High Volume, Low Pressure, German: high air volume, low pressure) is an internationally recognized low pressure process in painting technology. It is a variant of pneumatic spraying.
When spraying with HVLP paint spray guns, the sprayed material is atomized with a low nozzle internal pressure of 0.7 bar maximum. Here, a material transfer rate of up to 65 % is achieved.
This process reduces the speed difference between material and air flow, resulting in larger droplets and correspondingly less spray mist.
In order to produce an acceptable coating result when painting with HVLP paint spray guns, a higher volume of air is needed to atomize the injection molding material than with high-pressure guns.
The required air volume of 600 to 2,000 L / min can be generated either by a turbine or by a compressor.
HVLP painting is particularly suitable for highly fluid, low-viscosity materials. Even if more compressed air is consumed when painting with HVLP paint spray guns, the saving of the required paint usually outweighs the costs for the higher air consumption.
When painting the HVLP spraying is a slightly higher time than the conventional pneumatic spraying.
The HVLP standard was developed in the US in California and is the strictest environmental law in this regard. The air pressure under the air cap may not exceed 0.7 bar.