Proper needle/nozzle selection, Gun selection, Air caps – HP AUTOMATIC XT SPAY GUNS 311051D User Manual
Page 8
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Selection Charts
8
311051D
Proper Needle/Nozzle Selection
The spray gun's needle/nozzle kits range in size to pro-
vide different fluid flow rates.
As a general guideline, use the fluid nozzle that will give
the required flow with the needle fully triggered at a fluid
pressure of 5-20 psi (0.035 MPa, 3.5 bar - 0.14 MPa. 14
bar)
For low flow rates or light viscosity fluid, select the
smaller nozzle sizes.
For high flow rates or high viscosity fluid, select the
larger nozzle sizes.
For thicker, abrasive fluids, hardened SST needle tips
and nozzles are recommended.
Gun Selection
HVLP Guns
An HVLP gun is a high transfer efficiency gun that limits
the air pressure at the air cap to 10 psi (0.07 MPa, 0.7
bar) maximum. In some areas, an HVLP gun is required
for compliance with environmental standards.
Compliant Guns
A compliant gun is a high transfer efficiency gun that has
been tested to have a transfer efficiency greater than or
equal to HVLP guns. In addition, the compliant air cap
consumes much less air than the HVLP air cap.
The Graco compliant guns have no restrictions on air
cap pressures, but the gun inlet pressure must remain
under 30 psi (0.21 MPa, 2.1 bar) to remain in compli-
ance.
Airspray Guns
An airspray gun has excellent atomization and high pro-
duction rates typically with some reduction in transfer
efficiency.
Air Caps
The chart below lists the air caps available for pressure
feed, gravity, and siphon feed guns.
* Measured with gun nozzle 8 in. (203 mm) from target surface.
† Caps do not have alignment pin feature.
Spray Gun
Air Cap ID
Typical Pattern
Width*
in. (mm)
Gun Feed
Nozzle Orifice
in. (mm)
Part Number
HVLP
321A
15 (381)
Pressure Feed
.030-.070
(.75-1.8)
288134
HVLP
322
15 (381)
Pressure Feed
.086 (2.2)
234754†
HVLP
323
15 (381)
Pressure Feed
.110 (2.8)
234755†
Compliant
006A
11 (279)
All Models
.030-.070
(.75-1.8)
288132
Airspray
315A
13 (330)
Pressure Feed
.030-.070
(.75-1.8)
288133
Airspray
318
10 (254)
Pressure Feed
.086 (2.2)
234760†
Airspray
319
10 (254)
Pressure Feed
.110 (2.8)
234761†
Airspray
313
10 (254)
Pressure Feed
.030-.070
(.75-1.8)
234756†
Airspray
316
10 (254)
Pressure Feed
.030-.070
(.75-1.8)
234758†