Schmidt AmphiBlast 120, Operation And Maintenance Manual

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Copyright © 2019 Axxiom Manufacturing, Inc.
5.9 Deadman Valve/Switch (blast control)
The deadman valve/switch is part of a system that controls the blast operation. The deadman
valve/switch (#12) allows the operator to remotely start and stop the blast operation. The
deadman is mounted at the end of the blast hose assembly (#10) close to the blast nozzle (#11)
to give the operator easy control of the blast operation.
The Deadman is either a pneumatic valve or an electric switch depending on the type of
abrasive blaster control system. When the deadman lever is pressed down it sends either a
pneumatic or electric signal to the blast control valves (#20 & #64). The control valves open
and send an air signal to the automatic air valve (#9), the water shut off valve (#52) and the
Thompson Valve (#14). See Sections 9.8 and 9.9.
5.11 Abrasive Cutoff
There are three uses for the abrasive cutoff feature. The first is to allow blasting air and water
without abrasive (wash down). This is useful for washing off abrasive from item that has been
wet blasted. See Section 7.7 for instructions on the wash down procedure.
The second is to allow blasting air without water and abrasive (blow off). This is useful for
blowing off abrasive from an item that has been dry blasted or drying off an item after it has
been washed down. See Section 7.8 for instructions on the blow off procedure.
The third use is to purge abrasive out of a blast hose. This prevents abrasive from collecting in
the blast hose when the blast operation has stopped. The abrasive at rest in the blast hose can
cause surges when restarting the blast operation. To purge the hose after blasting, turn the
abrasive cutoff valve/switch (#62) to the “OFF” position and continue blasting until abrasive no
longer comes out of the blast nozzle (#11). See Figure 5.3.
Figure 5.3
– Abrasive Cutoff Controls