Gardner Denver DGH Series, Инструкция по эксплуатации

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3. Description
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3. Description
INLET
OUTLET
TOWER
4A
3A 9A
5C
1
8
7
6
2
3B 9B
TOWER
4B
5A 5B
5D
8
1
1. Tower Pressure Gauges
2. Purge Pressure Gauge
3. Inlet Switching Valves
4. Desiccant Drying Towers
5. Check Valves
6. Adjustable Purge Rate Valve
7. Purge Orifice
8. Safety Valves
9. Purge and Repres-
surization Valves
10. Purge Mufflers
11. Moisture Indicator
A & C Left Tower Suffixes
B & D Right Tower Suffixes
Process Stream
Purge Stream
INLET
OUTLET
4A
10A
9A 3A
TOWER
8
1
6
7
4B
3B 9B
TOWER
2
8
1
5C 5D
FIGURE 3-2a
TOWER 4A DRYING
TOWER 4B REGENERATING
FIGURE 3-2b
TOWER 4B DRYING
TOWER 4A REGENERATING
11
5A
11
5B
10B
10A 10B
3.3.2
Models 590 to 5
400 w/ Check Valves
(Refer to Fig. 3-2a.) Compressed air flows through inlet
switching valve (3A) (normally open) to tower (4A) where the air
is dried. After the air is dried it flows through outlet check valve
(5A) and then to the dryer outlet. A portion of the dry air, the
purge stream, branches off from the main air stream prior to the
outlet. The purge stream flow rate is controlled by the
adjustable purge rate valve (6) and the single purge orifice (7).
The purge flow, which has been throttled to near atmospheric
pressure, is directed through purge check valve (5D) to tower
(4B). As the purge flow passes over the desiccant in tower
(4B), it removes the water vapor which was deposited while the
tower was on-line drying. The purge air then passes through
purge and repressurization valve (9B) (normally closed) and
purge muffler (10B) to the atmosphere.
After regeneration, purge and repressurization valve (9B)
(normally closed) closes allowing tower (4B) to re-pressurize
slowly. Adequate repressurization time is allowed so that tower
(4B) is fully re-pressurized before switchover. After a controlled
time period, air inlet switching valve (3B) (normally open) opens
and inlet-switching valve (3A) (normally open) closes, purge
and repressurization valve (9A) (normally closed) then opens.
(Refer to Fig. 3-2b.) Tower (4B) is now drying the main air
stream while tower (4A) is being regenerated by the purge air
stream. The operation of the inlet switching (normally open) and
purge and repressurization (normally closed) valves is
sequenced by the control system located in the electrical
enclosure.