Wilkerson DE5 - Manual (Page 3)

DESCRIPTION OF OPERATION
Wilkerson DE series compact heatless air dryers employ the principles of pressure swing
adsorption (PSA). The operation is fully automatic and relatively little maintenance is required.
The dryers utilize two identical desiccant towers, a metering orifice, two shuttle valves, and two
2-way AC operated solenoid valves controlled by a solid state electronic timer. Wet air at line
pressure enters and flows through one of the towers where nearly all the water vapor is adsorbed
while the other tower is being regenerated. A repressurization period follows the regeneration
period. Every 60 seconds, the process is reversed, providing a continuous flow of dry air.
In the flow schematic shown below, Valve A (closed, de-energized) and Valve B (open, energized)
allow the inlet shuttle valve to direct the inlet air to flow into Tower A (drying). A portion of the dry
outlet air is allowed to flow through the outlet shuttle valve purge orifice into Tower B. This dry
purge air expands to nearly atmospheric pressure, sweeping the water out of the desiccant as it
flows through Tower B (regenerating) and out of the Valve B (energized) exhaust port. The timer
controls the cycling of normally closed solenoid valves.
The orifices are fixed and are sized by the factory based on flow, pressure and dew point required.
Flow Schematic
Figure 2
Instruction Manual / DE3, DE4 and DE5
Wilkerson Compact Heatless Air Dryers
EXHAUST
SOLENOID
VALVE A
INLET
SHUTTLE
VALVE
DESICCANT
TOWER A
OUTLET SHUTTLE
VALVE WITH
PURGE ORIFICE
DESICCANT
TOWER B
DRY AIR
TO APPLICATION
EXHAUST
SOLENOID
VALVE B
PURGE
AIR
EXHAUST
WET AIR IN
DE3, DE4 and DE5
DESICCANT
TOWER A
EXHAUST
SOLENOID
VALVE A
EXHAUST
SOLENOID
VALVE B
PURGE
AIR
EXHAUST
DESICCANT
TOWER B
DRY AIR
TO APPLICATION
OUTLET SHUTTLE
VALVE WITH
PURGE ORIFICE
INLET
SHUTTLE
VALVE
WET AIR IN