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System Information
System Description
Systems 970056 (55 gallon) and 970071 (30 gallon)
include a dual supply unit with pneumatic crossover for
continuous material supply. System 970073 (30 gal-
lon) is a single supply unit with a low–level shutoff. See
Fig. 1.
Each system air–powered ram pushes a follower
plate (C) into a drum of material, while the pump (A)
removes material from the drum and pushes it through
a supply hose to a customer–supplied header. Material
flows through the header to individual dispense drops.
WARNING
A main air bleed valve (E) and pump air bleed
valve (H), are required. These accessories help
reduce the risk of serious injury, including fluid
injection and splashing of fluid in the eyes or on the
skin, and injury from moving parts if you are adjust-
ing or repairing the pump.
The main air bleed valve (E) shuts off and relieves
the air to the pump and ram. The ram will hold
pressure if the ram director valve (U) is in the
horizontal (neutral) position. To relieve air pressure
in the ram, close the main air bleed valve (E) and
move the director valve (U) to DOWN. The ram will
slowly drop.
The pump air bleed valve (H) relieves air trapped
between it and the pump after the air is shut off.
Trapped air can cause the pump to cycle unexpect-
edly. Locate the valve close to the pump.
The fluid drain valve assists in relieving fluid pres-
sure in the displacement pump, hose, and gun.
Triggering the gun to relieve pressure may not be
sufficient.
System Accessories and Modules
Before you install the system, you should be familiar
with the parts discussed in the following paragraphs.
NOTE:
Reference numbers and letters in parentheses
in the text refer to the callouts in the figures and the
parts drawing.
D
Main air bleed valve (E)
is required in your system
to shut off the air supply to the pump and ram
(Refer to the preceding
WARNING
). When closed,
the valve bleeds off all air in the ram and pump, and
the ram slowly lowers. Be sure the valve is easily
accessible from the pump, and is located
upstream
from the air manifold (F).
D
Pump air bleed valve (H)
is required in your
system to relieve air trapped between it and the air
motor when the valve is closed (Refer to the pre-
ceding
WARNING
). Be sure the valve is easily
accessible from the pump, and is located
down-
stream
from the air regulator (G).
D
Air regulator (G)
controls pump speed and outlet
pressure by adjusting the air pressure to the pump.
Locate the regulator close to the pump, but
up-
stream
from the pump air bleed valve.
D
Air manifold (F)
has a swivel air inlet. It mounts to
the ram, and provides ports for connecting lines to
air-powered accessories.
D
Air line filter (J)
removes harmful dirt and moisture
from the compressed air supply.
D
Second
bleed-type air valve (K)
isolates the air
line accessories for servicing. Locate upstream
from all other air line accessories.
D
Pneumatic (Models 970056 and 970071) cross-
over (L)
provides switching between dual rams to
provide a constant supply of material to the system.
The crossover controls the air supply to each of the
ram air motors.
A low–level shutoff (L) (Model
970073)
provides automatic shutdown of a single
ram system when only a small amount of material
remains. The shutoff controls the air supply to the
ram air motor.
D
Ram air regulator (T)
controls the air pressure to
the ram.
D
Ram director valve (U)
controls the raising and
lowering of the ram.
D
Air release valve (V)
opens and closes the flow of
air to assist raising the ram plate (C) out of an
empty drum.
D
Bleed handle (CC)
bleeds air from under the ram
plate (C) to assist in priming the pump and lowering
the ram plate into the drum.