Gardner Denver DGH Series, Инструкция по эксплуатации

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3. Description
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3. Description
1. Tower Pressure Gauges
2. Purge Pressure Gauge
3. Inlet Switching Valves
4. Desiccant Drying Towers
5. Shuttle or Check Valve(s)
6. Adjustable Purge Rate Valve
7. Purge Orifice(s)
Purge Stream
Process Stream
8. Safety Valve(s)
9. Purge and Repres-
surization Valves
10. Purge Mufflers
11. Moisture Indicator
A & C Left Tower Suffix(es)
B & D Right Tower Suffix(es)
11
OUTLET
INLET
4A
10A
9A 3A
TOWER
8
1
5A
5C
6
7
4B
3B 9B
10B
TOWER
5B
2
5D
8
1
FIGURE 3-3b
Models 590 through 5400
TOWER 4A DRYING
TOWER 4B REGENERATING
A2
A1 B1
B2
4A 4B
3A
TOWER 4A DRYING
TOWER 4B REGENERATING
10A
9A
FIGURE 3-3a
10B
3B
INLET
9B
7
1
TOWER
1
2 6
8
7
TOWER
Models 40 through 450
A1
A2
B1
B2
OUTLET
11
5
3.4
Automatic P
urge Saving System
(Refer to Figure 3-3a for Models 40 through 450 and Figure
3-3b for Models 590 through 5400.)
Assume tower A is on-line drying while tower B has just gone off-
line to be regenerated. At the beginning of tower B’s
regeneration cycle a thermistor temperature measurement is
made at position B1. After the tower has been regenerated,
another measurement is made at B1. The drop in temperature
sensed during regeneration is an indirect measure of the water
vapor content of the inlet air. The Automatic Purge Saving
System’s microprocessor then uses this information to calculate
an allowable temperature rise in the bed during the drying cycle.
When tower B goes back on-line, a temperature probe at
position B2 measures the initial bed temperature at this point
and then monitors the bed until the calculated temperature rise
occurs. The temperature rise occurs as heat of adsorption is
released during the drying process. The time for the temperature
rise to occur depends on flow rate. At 100% flow the temperature
rise takes 5 minutes, at 50% flow it takes 10 minutes.
NOTE: If after 30 minutes, the bed temperature has not risen
to the calculated value, the dryer will automatically switch
towers.
When the calculated temperature rise is reached, the towers
switch with tower A now drying and tower B being regenerated.
Tower B regenerates for 3.9 minutes, re-pressurizes, and
remains idle until it is called upon for the next drying cycle.