Owner`s manual

HVLP System Components

Air Source

As with most sprayers, three distinct components make up an HVLP system:

air source, air hose, and HVLP spray gun. There are several variations of

these components depending upon the manufacturer. We will deal primarily

with Sherwin-Williams CAPspray equipment.

The air source is the heart of the system. It provides the CFM and PSI required

to atomize coatings. Depending on the type of gun and the application

requirements, there are two types of air sources–air compressor and turbine.

Air Compressor

Air compressors are used as the air source when using either direct hook-up

guns or high-flow regulator systems. Because of high CFM requirements with

HVLP direct hook-up guns, the minimum compressor size recommended is

5 HP. Due to the overall size and electrical requirements of 5 HP air compressors,

portability is limited. In most cases, direct hook-up guns which require an air

compressor as the air source are confined to stationary applications.

Turbine

The turbine is the most common air source found in the painting contractor

market. A turbine is a high-speed centrifugal blower motor which provides

the gun with high CFM flow at low air pressures. Because of the high

RPM–20,000 RPM in some cases–the air is frictionally heated. This eliminates

all moisture from the atomizing air. The high RPM also increases the atomizing

air temperature by as much as 80 degrees, reducing flash time and helping

to minimize blushing. All CAPspray turbines are commercially rated,

heavy-duty and designed for continuous use.

By-Pass Turbine with Tangential Discharge

The tangential discharge turbine is used in the by-pass configuration, using

separate cooling and intake fans. This turbine comes from the manufacturer

with a built-in air outlet. This type of turbine is found in the 5100, 8100 and

9100 units.

Although there are many variations and uses, the main function of a turbine

in HVLP equipment is to generate a high volume of air at air pressures less

than 10 PSI. A critical element in determining the amount of air pressure that a

turbine can generate is the number of stages. A stage, within a turbine, can be

viewed as an individual compression chamber. The greater the number of

stages within a turbine, the higher the PSI the turbine is able to produce–the

more PSI the turbine produces, the heavier the viscosity of material that can

be sprayed.

Cooling Fan

Brush (2)

Motor

Air Exhaust

Air Intake

2 Stage Turbine