Quincy Compressor QSB Series, Инструкция по эксплуатации

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Section VI - Servicing
28
Quincy Compressor ® - QSB/T ™
Differential Pilot Valve
WARNING!
Never adjust the pressure higher than the factory
setting. Death or serious injury and compressor
or property damage could result.
Open a manual vent valve to allow the compressor to
exhaust air to the outside and start the unit. By manual
regulation, slowly close the valve, allowing the unit to
build air pressure to the desired modulation point and
hold (100 PSIG standard). Adjust the screw on the
bottom of the differential pilot valve so that a slight
stream of air can be felt coming from the orifice adjacent
to the adjustment screw.
When the air is felt, air is beginning to pass through the
pilot valve to the air cylinder on the inlet valve, causing
the valve to modulate toward its closed position, thereby
reducing the volume of air being compressed.
To raise the pressure, turn the adjusting screw in
(clockwise). To lower the pressure, turn the screw out
(counter clockwise). Maximum full load pressure is 100
PSIG for standard QSB/T
™
units. Minimum full load
pressure with modulation and standard controls is 75
PSIG.
Pressure Switch
The pressure switch determines what pressure the
compressor will load and unload. Standard factory
settings are listed in the QSB/T Specifications. If a
lower setting is desired, adjust the differential pilot valve
first and set the pressure switch cut-out point to 15 PSIG
over the desired full load pressure. The range
adjustment is made by turning the screw clockwise to
increase the cut-in/cut out pressure. The pressure switch
should unload the compressor by the time it reaches the
20% load point. Raising the pressure without changing
the compressor speed above factory settings will result in
high amp draw and drive belt failures. Consult your parts
book for proper sheave and belt part numbers.
Water Temperature Regulating Valve
(Water-cooled units Only)
The water temperature regulating valve senses fluid
temperature and opens or closes, regulating water flow
from the unit. It is factory set to maintain 180°F
discharge temperature. Due to different incoming water
temperatures and/or pressures in various locations, valve
adjustment should be checked during start-up to
maintain 180°F discharge temperature. To increase fluid
temperature, decrease water flow by turning the
adjustment screw clockwise. To decrease fluid
temperature, increase water flow by turning the
adjustment screw counter clockwise. Water pressure
should be 40 psi minimum/100 psi maximum. Water
temperature should be 50°F minimum/90°F maximum.
V-belt Drive Maintenance
QSB/T
™
15 through 30 HP units are equipped with a
pivoting motor base with a spring tension belt tensioning
device. QSB/T
™
40 & 50 HP units are equipped with a
pivoting motor base with a jackbolt for tensioning the
belts. For the best belt life, factory-matched belt sets
must be used with these drive.
The most important factors in the successful operation of
a v-belt drive are proper belt tensioning and sheave
alignment. Too little tension can result in slippage,
causing rapid belt and sheave wear, too much tension
can result in excessive stress on belts, bearings, and
shafts. Misalignment causes wear and increases the
probability of belt turnover by decreasing stability.