Quincy Compressor 50093-103 - Manual (Page 58)

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Section 7 - Service Adjustments
Differential Pilot Valve
Open a manual vent valve on the inlet to the vacuum
pump and start the unit. By manual regulation slowly close
the valve, allowing the system pressure to reach the
desired vacuum level. Adjust the screw on the bottom of
the differential pilot valve so that a slight vibration can be
detected at the point of desired system modulation. When
this vibration 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 drawn in to the pump.
To raise pressure, turn the adjusting screw in (clockwise).
To lower pressure, turn the screw out (counterclockwise).
Maximum vacuum under modulation is 29.6' HgV. for the
QSVI vacuum pumps (29.9" HgV without modulation).
Vacuum Switch
The vacuum switch determines at what pressure the
vacuum pump will load and unload. Standard factory
settings are listed in the QSVI Specifications. If a lower
setting is desired, adjust the differential pilot valve first
and set the pressure switch cut-out point to no less than
2" HgV differential. That adjustment is made by turning
the wheel clockwise to increase the cut-in/cut-out
pressure and counterclockwise to lower the cut-in/cut-out
pressure. The vacuum switch should unload the vacuum
pump by the time it reaches the 20% load point.
Water Temperature Regulating Valve (water-cooled
units)
The water temperature regulating valve senses fluid
temperature and opens or closes, regulating water flow
from the unit. It is factory set to maintain 160°F fluid
injection temperature as shown by the fluid inlet
temperature gauge. Due to different incoming water
temperatures and/or pressures at the customer location,
valve adjustment should be checked during start-up to
maintain 160°F fluid inlet 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 counterclockwise.
Coupling Alignment
Compressor and motor bearing life can be maximized only
when both components are in alignment to each other.
Prior to new unit start-up or after any vacuum pump or
motor change the drive alignment must be checked. If the
vacuum pump is ever accidentally knocked out of place or
relocated, the drive alignment must be checked. Note!
Some QSVI models are permanently aligned and the
above statement will not apply to those models. Check
your machine for alignment type.
Drive Coupling Specifications
Model Angular
Alignment Specifications
Parallel Element
Bolt Size Element
Bolt
Torque
QSVI 75,
100 &
200
0.004 0.008 3/8" 30 ft./ lbs.
See instruction section prior to start up.
The Quincy QSVI series vacuum pumps utilize a 2
piece flexible element bolted to steel hubs on the pump
motor shafts. The following steps will insure a properly
aligned coupling:
1.) Disconnect all power to the unit. Lockout the main
power switch and hang a sign at the switch of the unit
being serviced.
2.) Remove the drive guard.
3.) Unbolt and remove one-half (1/2) of the flexible
element. Leave the remaining half, bolted to both steel
hubs.
4.) Using one of the existing 3/8" bolt holes in the
vacuum pump hub, screw a dial indicator mounting stud or
bolt in firmly.
5.) Attach a dial indicator to the mount with the
necessary hardware to allow the indicator plunger to
contact the motor hub.
NOTE: Four viewpoints need to be checked. Angular and
Parallel as viewed from the top. Angular and Parallel as
viewed from the side.