Ransburg, Brake air, Electrostatic voltage – Ransburg Aerobell (Std.) Rotary Atomizer A12381 User Manual
Page 40: Shaping air, Fluid flow rate control
BRAKE AIR
Brake air is used to slow the turbine speed. It is
advantageous for short color change cycle times,
and may be used for stopping the turbine. Use of
the brake involves (1) turning off turbine drive air,
and then (2) turning the brake air on for a short
duration. For example, the air brake will reduce the
turbine speed as shown in "Braking Time" chart.
ELECTROSTATIC
VOLTAGE
Depending upon the power supply model used,
the maximum output voltage of the power supply
can vary. The actual voltage setting will depend
upon various coating application requirements.
The level of voltage applied to the Aerobell plays
an important role with regard to pattern size,
efficiency (wrap), penetration into cavity areas,
and target distance.
SHAPING AIR
Shaping air is used to shape the spray pattern.
The lower the pressure, the wider the pattern, and
conversely, higher pressures result in narrower
patterns. Shaping air does not help atomize the
material, but does assist in the penetration of
atomized particles into cavity areas. Shaping
air should be kept at a minimum consistent with
coating requirements. Excessive shaping air will
cause some atomized particles to blow by the
target not allowing full “wrap,” or paint particles
to bounce back onto the atomizer.
FLUID FLOW RATE
CONTROL
Externally mounted fluid regulators or gear pumps
are typically used to control fluid flow.
The atomizer assembly is equipped with valves
which are pneumatically operated to direct the
flow of paint to either the feed tube or dump line
and to supply an intermittent solvent to clean the
interior of the bell cup.
Three (3) fluid tube sizes are available: 1/16",
3/32", and 1/8" (1.6mm, 2.4mm, and 3.2mm).
>
Electrical discharge of a high electrical
capacitance fluid/paint system can cause
fire or explosion with some materials. If
arcing occurs when a specific coating ma-
terial is used, turn the system off and verify
that the fluid is non-flammable. In these
conditions, the system is capable of releas-
ing sufficient electrical and thermal energy
to cause ignition of specific hazardous
materials in the air.
To Brake From
(RPM)
60,000 to 40,000
60,000 to 20,000
60,000 to 0
40,000 to 20,000
40,000 to 0
Seconds
(Approx.)
3.7
7.5
12.9
4.0
9.0
Braking Time (at 90 psi Brake
Air Pressure)
Brake air should be interlocked so that it is im-
posible for air to be applied to the braking system
while the turbine air is on.
W A R N I N G
!
Aerobell - Operation
36
LN-9264-08.2
Ransburg