Selection Charts
Selection Charts
TERMS
Light Fluid: Up to 18 seconds with No. 2 Zahn cup (20 centipoise)
Medium Fluid:19 to 28 seconds with No. 2 Zahn cup
Heavy Fluid: Greater than 28 seconds with No. 2 Zahn cup (greater than 64 centipoise)
2.8Volatile Organic Compounds,
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. See the Air Cap chart, page 8, for maximum inlet pressure.
LVMP Guns
An LVMP gun is a high transfer efficiency gun that has been tested to have a transfer effi- ciency greater than or equal to HVLP guns. In addition, the LVMP air cap consumes much less air than the HVLP air cap. Graco LVMP guns have no restrictions on air cap pressures.
Conventional Guns
A conventional gun has excellent atomization and high production rates typically with some reduction in transfer efficiency.
HiTEch Guns
A HiTEch gun is a high transfer efficiency gun with excellent atomization. Graco HiTEch guns have no restrictions on air cap pressures.
Proper Needle/Nozzle Selection
The spray gun's needle/nozzle kits range in size to provide different fluid flow rates. As a general guideline, use the fluid nozzle that will give the required flow with the needle fully trig- gered at a fluid pressure of
•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 abrasive fluids, the gun models with tungsten carbide needle tip and nozzle are recommended.
Orifice Size |
| Flow |
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in. | mm | Viscosity | oz/min |
| cc/min |
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0.020 | 0.5 | light |
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0.028 | 0.7 | light |
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0.035 | 0.9 |
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0.039 | 1.0 |
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0.043 | 1.1 |
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0.051 | 1.3 | medium |
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0.059 | 1.5 | medium |
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6 | 313869B |
