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DESICCANT
BED
OIL COALESCING FILTER
(BENDIX®
OIL COALESCING AIR DRYER)
DELIVERY
PURGE CHECK VALVE
CONTROL (OPEN)
CHANNEL
GOVERNOR
UNLOADER
PORT
Note 1:
The Bendix®
PURGE
PURGE RESERVOIR
ORIFICE
PRESSURE
PROTECTION
VALVES
SUPPLY | PURGE VALVE | A | B | C | D |
PORT |
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| (CLOSED) | PRIMARY |
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| TURBO |
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| SAFETY PORT (PRI) |
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| PURGE | ||
| VALVE |
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| VALVE |
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| SECONDARY |
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| RESERVOIR | |
| ENGINE (OPEN) |
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| DRAIN VALVE | ||
| TURBO | PORT (SEC) |
| PRIMARY |
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| COMPRESSOR | SEE | RESERVOIR | SECONDARY | |
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| NOTE 1 |
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| RESERVOIR | |
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| AUXILIARY PORTS | |
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| (TO ACCESSORIES) |
DIAGRAM SHOWS ALL PRESSURE
PROTECTION VALVES OPEN.
FIGURE 2 - BENDIX® AD-IS® AIR DRYER AND RESERVOIR SYSTEM CHARGE CYCLE
CHARGE CYCLE (Refer to Figure 2.)
When the compressor is running loaded (compressing air), compressed air flows through the compressor discharge line to the inlet (1/IN) port of the air dryer body. The compressed air often includes contaminates such as oil, oil vapor, water, and water vapor.
Traveling through the discharge line and into the air dryer, the temperature of the compressed air falls, causing some of the contaminants to condense and drop to the bottom of the air dryer and purge valve assembly. These contaminants are ready to be expelled at the next purge cycle. The air then flows into the desiccant cartridge, where it flows through an oil
Air then flows into the desiccant drying bed and becomes progressively more dry as water vapor adheres to the desiccant material in a process known as adsorption.
Dry air exits the desiccant cartridge, through the center of the base assembly, then flows to the delivery check valve and through an orifice and into the purge reservoir. The delivery check valve opens, supplying air to the pressure protection valves (A) through (D) simultaneously, the safety valve, and also to the reservoir port of the attached governor. The purge reservoir fills, storing air that will be used to regenerate the desiccant during the purge cycle. This air is available to supply downstream components during the charge mode.
When the air pressure reaches approximately 106 psi, the four pressure protection valves will open and air will be supplied to the primary reservoir, secondary reservoir, and
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