Adjust Spray Pattern - Graco AUTOMATIC XT SPAY GUNS 311051D Instructions - Parts Manual

Adjust Spray Pattern

Do not exceed 100 psi (0.7 MPa, 7 bar) maximum fluid
and air pressure. Higher pressures can cause parts to
rupture and result in serious injury.
The spray gun fluid flow is controlled by the fluid pres-
sure regulator and the fluid control knob. Use the fluid
pressure regulator to adjust the general fluid flow and
the fluid control knob to make precise fluid flow adjust-
ments.
CAUTION
Use caution when operating the fluid control valve
near the closed position. The plastic needle tip may
be damaged if forced too hard against the nozzle seat
by the fluid control valve.
Follow these steps to establish the correct fluid flow and
air flow:
1. To achieve desired flow, adjust the fluid flow using
the fluid pressure regulator (L) installed in the gun
fluid line. Typical industrial flow rates will vary with
regulator pressures from 5 to 30 psi (34 to 210 kPa,
0.3 to 2.1 bar). If the fluid pressure is too low at the
desired flow rate, install a smaller nozzle. If the fluid
pressure is too high, install a larger nozzle.
For spray guns equipped with the fluid control knob,
you can make flow rate changes at the spray gun.
Rotate the fluid control knob clockwise to reduce the
flow.
L
F . 12: Fluid Pressure Regulator
IG
311051D
A larger fluid nozzle at a reduced fluid pressure will
maintain the same flow rate, but the fluid stream
(velocity) will slow down. When air is applied, this
allows air to act on the fluid longer and improve the
atomization.
2. Using the air pressure regulator (F), set the fan and
atomizing air supply pressure per Table 1. Use
these suggested settings as a starting point.
Table 1: Suggested Starting Settings
Airspray
HVLP
Compliant
HVLP and Compliant Gun Limits
HVLP Guns: local laws may limit the maximum
pressure to 10 psi (70 kPa, 0.7 bar) at the air cap
for compliance. 35 psi (25 kPa, 2.5 bar) inlet air
yields 10 psi (70 kPa, 0.7 bar) at the air cap. To
measure pressure at the air cap, use the accessory
tapped air cap. See Accessories, page 33.
Compliant Guns: the maximum inlet pressure to the
manifold is 30 psi atomizing air.
TI7019a
Atomization Air
Fan Air (psi)
35
25
18
Setup
(psi)
35
25
25
15