HP AUTOMATIC XT SPAY GUNS 311051D - Manual (Page 15)

Setup
311051D 15
Adjust Spray Pattern
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.
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.
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
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.
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.
F IG . 12: Fluid Pressure Regulator
L
TI7019a
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.
Fan Air (psi)
Atomization Air
(psi)
Airspray 35 35
HVLP 25 25
Compliant 18 25
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.