HVLP Spray Guns

Home

What is HVLP

HVLP Systems

Components

Accessories

F.A.Q

Webstore

Old Parts - Discontinued

WHAT IS HVLP?

To qualify under the term HVLP, air flowing through the Aircap must not exceed 10 psi. Generally speaking, HVLP turbine motors produce over 100 CFM (cubic feet per minute) at 3 - 8 psi. (pounds per square inch) depending on the model of motor. Compare this to a typical high pressure set-up where 45 - 60 psi at 8 CFM would be the norm. HVLP turbines supply air at a much lower velocity producing a softer, easier to control spray. This allows you to lay the paint on gently and not blast it on. Benefits of HVLP include less overspray and less paint wastage. Transfer efficiency can be as high as 85%. The quality of finish is identical to the best high pressure spray finishes.

In some areas of the USA. (Southern California for instance), high pressure q3_pro_hvlp_spray_system

spray systems are prohibited in certain industries. All HVLP turbine systems, (by any maker) automatically comply with all known regulations in North America.

There seems to be a lot of confusion about what kind of motor is used in the turbines. Standard built-in residential type vacuum motors are used by all HVLP makers. Although years ago a few systems were built with non-tangential motors, any industrial HVLP turbine made in North America today will use a tangential motor. Ametek-Lamb Electric (Ohio) is the premier maker of such motors and the main choice of HVLP makers.

HVLP makers typically give CFM specs unrestricted. The outlet on the motor itself is 1½" and this is where 100 CFM plus can be measured. But once the outlet is reduced, the air is restricted so that only a fraction of the unrestricted air can possibly pass through the air cap of the spraygun. If the area of the air holes (orifices) in a typical HVLP air cap are added together, the combined diameter will only be about 3/8". Although much is said about how high the CFM rating is on these motors, the fact remains that because the pressure is low, only around 12 - 20 CFM passes through the air cap anyway - the rest of the air is surplus. In fact, using a ‘Y’ connector, 2 sprayguns can be attached to the turbine and no real loss of power will be noticed. At very low pressures, with this type of turbine motor, psi becomes much more important than CFM. The more pressure that is used, the more CFM passes through the air cap. It is therefore the pressure that forces more air through the same air cap. The result is better atomization with the higher pressure.

Although sealed pressure can be measured with a gauge, it is often highly inaccurate. True pressure is calculated by a simple formula. H20 Inches X .036 = PSI. Ametek-Lamb Electric supplies accurate measurements of the H20 Inches (amount of inches of water the motor can push up a vertical tube) for all its motors. Another indication of motor power is the Operating Amperage. UL and CSA rate the motors under actual use (spraying water), to determine the true operating amperage. The Fuji Mighty-Mite Model (discontinued) used a 2-stage motor that produced 110 CFM at about 4 psi. The operating Amperage was rated at 8.7 amps. The Fuji Mini-Mite 3-stage motor produces less CFM than the 2 stage - 101 CFM at 6 psi but the operating amperage is rated at 11.5 amps. The Fuji Mini-Mite Model uses the Ametek-Lamb Electric 5.7" diameter, 3-stage motor that is the most powerful in its class. It is generally agreed that to spray the newer water-based/borne coatings a 3-stage (minimum) is required.