2201Q4JE-MY-C9-N_2018.01.
Chapter 6 Troubleshooting
Compound 2-stage Screw Compressor 4032**C
6-7
08: Leak from mechanical seal (continued)
Direct cause
Root cause
Action
Poor contact of sliding
surfaces
Foreign matter attached to
sliding surfaces, due to
contaminated lubricating oil.
Replace the whole quantity of
lubricating oil.
Install bypass filter to oil supply line.
Faulty assembly of parts
Human error
Disassemble, replace parts and
reassemble.
Use assembly check sheet to ensure
confirmation.
09: Squeaking of mechanical seal
Direct cause
Root cause
Action
During initial period after
exchange for new
mechanical seal, squeaks
may be heard from sliding
surfaces until they fit
together.
As the sliding surfaces are very
hard and dense, they need
time to fit together.
Squeaking itself does not cause leak
from seal or deterioration in sealing
function.
Normally, squeaking is heard for
several dozens of hours, however, it
may last longer in rare cases.
→In this case, contact our service
center.
10: Capacity control position is indicated incorrectly
Direct cause
Root cause
Action
Inaccurate reading of
compressor indicator
gauge.
Screw for securing indicator
needle is loose.
Manually operate the compressor's
capacity control to indicate 0 %
position, and tighten the screw again.
Indicator's bevel gears are
worn.
If deteriorated over time, replace.
If the wear is caused by excessive
vibration of the compressor, take
measures to reduce vibration and
then replace the bevel gears.
Inaccurate reading of
capacity control indicator
on the control panel.
The cam groove of
compressor's indicator cam is
worn.
Often caused by continued operation
with load on a certain point.
→Replace the indicator cam.
* The currently shipped indicator cam
has its grooved portion
strengthened.
The guide pin of the
compressor push rod is worn.
Currently, this pin is also improved in
resistivity against wear. If the indicator
cam is replaced with the improved
version, replace the pin with the
countermeasure part.
Failure of potentiometer
If the part is deteriorated over time or
loaded at a certain point during
operation for a long time, replace it.
If the wear is caused by excessive
vibration of the compressor, take
measures to reduce vibration and
then replace the potentiometer.
Improper zero span adjustment
of E/E positioner
Readjust.
