BENDIX SD-08-2414 用户手册

 oil coalescing air dryer.  The AD-IP air 

dryer alternates between two operational modes or “cycles” 

during operation: the Charge Cycle and the Purge Cycle. 

The following description of operation is separated into 

these “cycles” of operation.

When the compressor is loaded (compressing air) 

compressed air — along with oil, oil vapor, water and water 

vapor — flows through the compressor discharge line to the 

supply port of the air dryer body.

As air travels through the end cover assembly, its direction 

of flow changes several times, reducing the temperature, 

causing contaminants to condense and drop to the bottom 

or sump of the air dryer end cover.

After exiting the end cover, the air flows into the desiccant 

cartridge. Once in the desiccant cartridge the air first flows 

through an oil separator, located between the outer and 

inner shells of the cartridge. The separator removes water 

in liquid form as well as liquid oil and solid contaminants.

Air, along with the remaining water vapor, is further cooled 

as it exits the oil separator and continues to flow upward 

between the outer and inner shells. Upon reaching the top 

of the cartridge the air reverses its direction of flow and 

enters the desiccant drying bed. Air flowing down through 

the column of desiccant becomes progressively drier as 

water vapor adheres to the desiccant material in a process 

known as “ADSORPTION.” The desiccant cartridge using 

the adsorption process typically removes most of the water 

vapor from the pressurized air.

Dry air exits the bottom of the desiccant cartridge and flows 

through the center of the bolt used to secure the cartridge 

to the end cover. Air flows down the center of the desiccant 

cartridge bolt, through a cross drilled passage and exits 

the air dryer delivery port through the delivery check valve.  

DESICCANT 

BED

DELIVERY 

CHECK VALVE

PURGE 

VOLUME

DISCHARGE 

PORT

EXHAUST

PURGE 

VALVE

TURBO 

CUT-OFF VALVE

ENGINE 

TURBO

COMPRESSOR

GOVERNOR

PURGE 

CONTROL 

LINE

CONTROL 

PORT 

SUPPLY 

PORT

OIL 

SEPARATOR

PURGE 

ORIFICE

Note 1:
The Bendix

®

 AD-IP

® 

air dryer and reservoir 

system purge piston has a purge control 

channel drain. This allows any condensation 

in this area to flow past a diaphragm in the 

top of the purge piston and out through a 

channel in the middle of the central bolt of 

the purge assembly to be drained. During 

the purge cycle this drain is closed.