Ransburg Aerobell Copes 75850 - Manual (Page 18)

> Operators must be fully trained in safe
operation of electrostatic equipment. Op-
erators must read all instructions and safety
precautions prior to using this equipment. (Ref.
NFPA-33 / 1995 edition, Ch 16.)
TURBINE SPEED
The speed of the turbine is determined by the
air inlet pressure. See Figure 4 “TURBINE AIR
PRESSURE/RPM/SCFM,” under Air Filtration
Requirements section for more information.
The desired speed will depend upon the type
of coating material and various application
requirements.
Turbine speed may be controlled by use of optional
Pulsetrack TM or eurocard atomizer module speed
monitor and control. Contact your Ransburg
representative for more information on this optional
equipment.
Bearing damage (and subsequent turbine failure)
caused by running the turbine without bearing air
will not be covered under Ransburg warranty.
When turning the turbine ON, bearing air must
OPERATION
BEARING AIR
> Air bearing air must be ON whenever the
turbine is operated. If not, severe bearing
damage will occur. It is recommended to leave
bearing air ON at all times. During mainte-
nance or disassembly, turbine air must be OFF
for at least 3 minutes before shutting OFF bear-
ing air or main line air.
Nominal bearing air pressure is 80 psi, with an
operating range of 60 psi minimum to 100 psi
maximum. Under no circumstances should the
turbine be operated with less than 60 psi bearing
air pressure.
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 Figure 7.
Figure 7: Braking Time
(At 90 psi Brake Air Pressure)
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
Aerobell Copes - Operation
14
be present. Likewise, bearing air must remain ON
when the turbine air is turned OFF until the turbine
stops spinning. Never turn OFF bearing air to cause
the turbine to stop spinning. Brake air can be used
to slow the turbine (see next section on Brake Air),
wait for the turbine to stop spinning before turning
bearing air OFF.
LN-9230-00.1
W A R N I N G !
> Never over brake allowing the bell cup to
spin the opposite direction of drive rotation
(CCW) facing the bell cup.
C A U T I O N !
C A U T I O N !
> Excessive speed will cause air turbine
damage. Do not exceed the maximum rated
intermittent speed of 60,000 rpm.
C A U T I O N !
> Operating the turbine with bearing air
pressure below 60 psi (measured at turbine
inlet) may cause bearing damage.
C A U T I O N !