Tips on how to select the appropriate painting nozzle
28.11.2017
The nozzle – a small element of the entire painting equipment – becomes extremely relevant for the overall quality of the painting operations.
In principles, the airless painting pumps are spraying the paint under high pressure (up to 550 bars) through the nozzle, pulverizing it onto the surface to be coated. The nozzle is, under these circumstances, crucial for the way in which the pump is working and for maintaining the same pressure level during the entire application. It is also responsible for the atomization of the paint, which should take place at a specific spraying angle and at a specific flow speed.
While the pump is responsible for the working pressure, the nozzle determines the spraying angle and its force.
Why is it so important to choose the right nozzle for each application in part?
The suitable nozzle is the one able to ensure the appropriate consumption of paint and a clear control of costs and quality. As a consequence, not only that one would use less material, but also the works will be finished better and sooner.
A variety of nozzles’ types and sizes
Choosing the right nozzle is similar to opting for the appropriate drill for your drilling machine. There are special drills for wood, others for metal, and others for concrete. Each drill’s type comes in different sizes. Evidently, using the wrong drill with the wrong material will affect the results of the operation. The same is valid in case of nozzles too.
Not all nozzles look alike
The color of the nozzle is the one letting you know for which type of application it was designed. There are 4 types of nozzles:
- Green ones – guaranteeing the best quality of the finish when working at low pressure. It’s recommended for finishing works and for wall paintings.
- Blue ones – to be used for wall painting and actually for any type of spray applications
- Brown ones – to be used for thin blasters and for less fluid paints
- Yellow ones – for road marks
Each nozzle is inscribed with a 3 numbers code. The first number indicates the footprint of the operation, which corresponds to the spraying angle. If this number is 5, than the spraying angle is 500. If you multiple this number with 5 than you will determine the footprint for the situation in which the paint would be applied from 30m away from the surface to be processed.
The last 2 numbers from the code offer indications about the spraying orifice of the nozzle. The bigger the number, the stronger the paint spray will be.
3 steps for choosing the right nozzle
For which application will you use it?
As mentioned before, the nozzles have been designed for different types of application. The materials to be used when willing to obtain a high quality finish are to be sprayed with a nozzle with small pulverizing orifice. For more dense materials such as latex the spraying orifice has to be bigger. Considering the nozzle’s color, it is very simple to establish what’s more suitable for each application in part.
How big should be the footprint of the painting operation?
The footprint is determined by the spray angle when the paint is applied from 30m away from the surface to be covered. The bigger the angle, the faster the coating will be finished. Still, this will be achieved while consuming a supplementary amount of paint. When the angle is smaller, one uses less material, the final result is easily controllable, but the operation itself will take longer.
Choosing the size of the footprint and dividing it to 5 will help you to determine the first number from the code, which is inscribed on the nozzle.
Which is the maximum spray flow you can achieve during the painting operation?
The size of the nozzle’s orifice determines the quantity of the paint that will go through it during application. The maximum flow of the paint should always be bigger than the one of the nozzle.
Get all from the nozzle you use!
Replacing the nozzle at the right moment ensures the quality of the painting operation and saves supplementary costs generated by eventual repair works that might be necessary in case of overusing this consumable.
