CLASSIC BLAST MACHINE with TLR-100/300 REMOTE CONTROLS
Page 14
© 2018 CLEMCO INDUSTRIES CORP.
www.clemcoindustries.com
Manual No. 22501, Rev. I 02/18
3.5
Operation and Function of the Choke Valve
Figure 14
3.5.1
Always fully open the choke valve while blasting;
open is when the handle is vertical and aligned with the
piping as shown in Figure 14.
Figure
14
3.5.2
Closing the choke valve while blasting lowers
pressure in the pusher line from the pressure in the
vessel. Closing the valve forces abrasive through the
metering valve to clear minor blockage, such as damp
abrasive, or is used to rapidly empty the machine at the
end of the day.
NOTICE
Do not blast with choke valve closed or partially
closed. Prolonged blasting with the choke valve
partially closed will accelerate wear on the
metering valve.
3.6
Operation of the Optional Abrasive Cutoff
Switch (ACS) - Figure 15
3.6.1
The ACS closes the metering valve so that air
alone without abrasive exits the nozzle. Common uses
for this feature are:
1. Clearing abrasive from the blast hose when blasting
is finished. This is helpful in a lot of applications and
necessary when the blast hose is vertical to prevent
abrasive from collecting in low spots in the blast hose,
eliminating excessive abrasive slugging at startup.
2. Blowing abrasive off the blasted surface. Note:
Small amounts of residual abrasive may exit the nozzle
with the air, requiring blowing off or otherwise cleaning
surface outside the blasting area prior to painting.
3. When wet blasting with an injector or wetblast
attachment, it is used to assist in drying the surface after
it is washed down.
WARNING
OSHA sets exposure limits for people and the
environment. Airborne dust can increase the
exposure levels beyond permissible limits. OSHA
prohibits blowing with compressed air as a cleaning
method for lead-based paint dust or other hazardous
dust, unless the compressed air is used in
conjunction with a ventilation system designed to
capture the volume of airborne dust created by the
compressed air, 29 CFR 1926 (h). The ACS is for
blowing off abrasive from a blasted surface, NOT for
general area cleanup.
3.6.2
The abrasive cutoff switch is situated directly
behind the control handle. The switch may be flipped
open or closed at any time, but will not operate the
metering valve unless the control handle is pressed.
3.6.2.1 Blast Mode:
Moving the ACS toggle away from
the nozzle to the ON (CYL port) position sends control
air to the abrasive metering valve opens the valve so that
the blast machine operates normally with air and abrasive
coming out the nozzle.
Figure
15
3.6.2.2
Blowdown
Mode:
Moving the ACS toggle toward
the nozzle to the OFF position cuts off the control air to the
abrasive metering valve, closes the valve, and stops the
abrasive flow. This action allows air alone to exit the
nozzle, useful for clearing the blast hose before shutting
down, and blowing abrasive and water off the blasted
surface.
3.7 Stop
Blasting
3.7.1
To stop blasting, release the control handle
lever. The inlet valve closes, the outlet valve opens, and
the blast machine depressurizes. The pop-up valve
Choke Valve
Valve is shown open;
handle position is
aligned with the piping.
Blast Mode
Toggle pointing away from nozzle.
Blowdown Mode
Toggle pointing toward nozzle.
ON
OFF
