Commissioning of paint spray gun

August 22, 2022

The debugging content of the paint spray gun is as follows:

(1) Pressure adjustment. Adjust the pressure of the spray gun strictly according to the construction parameters provided in the paint manual
For any paint system, there is only one most suitable air pressure, which is the lowest air pressure that can obtain the best atomization of the paint. The optimum pressure is the minimum pressure required to obtain proper atomization, evaporation rate and spray fan width.
If the pressure is too high, a lot of paint will be wasted due to flying paint, and the solvent will evaporate quickly before reaching the surface of the component, resulting in poor fluidity and prone to defects such as orange peel.

Too low pressure results in poor drying performance due to too much solvent retention, and the paint film tends to blister and sag. There are optimum values for the air pressure required when spraying different paints.

(2) Adjust the size and direction of the fog beam
A. Size: screw the knob of the fog control valve all the way in to get the smallest circular fog beam, and screw out the knob all the way to get the largest fog shape.

B. Direction: Adjust the air cap to change the direction of the fog beam. Adjust the angle of the air cap to be parallel to the ground, and the spray mist is flat and perpendicular to the ground.

(3) Paint flow adjustment: Use the paint flow control valve to adjust the paint flow according to the selected fog shape. When the control valve is screwed out, the paint flow increases, and when the control valve is screwed in, the paint flow decreases.

(4) Paint distribution test: Through the fog test, see the sagging situation and check whether the adjustment is correct. Loosen the air cap retaining ring and rotate the air cap so that the bell mouth is in a vertical position and the spray pattern is horizontal. Spray again, hold the trigger until the paint starts to flow down, i.e. sag. Check the sag condition, all adjustments are correct, and the length of each sag should be approximately equal.
(If the sag is split, it is because the jet is too wide or the air pressure is too low. Turn the mist control valve a half turn in, or increase the air pressure a bit, alternating between these two adjustments until the sag length is even. If the hanging middle is long and the two sides are short, it is because there is too much paint sprayed, and the paint flow control valve should be tightened until the sagging length is uniform.)

Author:

Mr. Michael Mok

E-mail:

michael@nichiyopt.com

Phone/WhatsApp:

8613822492111