Rhino
R
VE Bulk Unloaders, 125-mm Frame
13
Part 1608271-04
E
2019 Nordson Corporation
Theory of Operation
The following paragraphs provide a theory of operation for the unloader.
Basic Operation
A straight-sided container of adhesive or sealant material is centered
between the drum centering shoes and under the follower plate. The
elevator consists of two air-driven pistons that lower the follower plate into
the container of material. The rubber seals around the outer edge of the
follower plate create an airtight compartment below the follower plate.
Downward movement of the follower plate forces material into the hydraulic
section of the pump.
Pneumatic Controls
Refer to the
Pneumatic Schematics
section to see the applicable unloader
pneumatic schematic.
The operating controls for the unloader are completely pneumatic. Clean,
dry shop air filtered to 5 microns is supplied to two pressure regulators: one
for the pump air motor and one for the elevator cylinders and blow-off
supply.
Air Motor Supply
The regulated air supply flows through a shutoff valve before it enters the
pump air motor.
Unregulated air at full shop pressure is supplied to the pilot and
intermediate valves. These valves supply pilot air to the main motor control
valve. This higher pressure signal air enables the air motor to make rapid
directional changes regardless of the regulated supply air setting.
An optional pressure relief valve is used in line with the air motor supply to
limit the pump output pressure. The pressure relief valve is designed to
vent at a pre-determined setting whenever the air motor supply pressure
exceeds the air motor regulator setting. Lowering the air motor supply
pressure resets the relief valve.
NOTE:
System pressure requirements may need to be limited due to
component pressure ratings or other system requirements. A different
pressure relief valve of the desired pressure range can be selected to
prevent the system from being over pressurized.
