Fig. 2 Installation of oil mist trap
4. PERFORMANCE OF OIL MIST TRAP
4.1
Limit of Pump Operation Hours
The pump operating time is limited when the pump is operated continuously at a high
suction pressure.
Table 3 gives the relationship between the continuous operating time and the suction
pressure of the pump.
Stop the pump once for more than five minutes within this time so that oil returns to
the pump.
If the pump is continuously operated at a high pressure, oil may gush out through the
exhaust port.
Table 3
Relationship between Continuous Operating Time
and Suction Pressure of Vacuum Pump
Continuous suction pressure
Maximum operating time
13.3 to 12 KPa
Within 3 hours
12 to 10 KPa
Within 5 hours
10 to 8 KPa
Within 8 hours
8 to 6 KPa
Within 15 hours
6 to 4 KPa
Within 22 hours
4 to 2 KPa
Within 33 hours
2 to 1 KPa
Within 55 hours
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NOTE : This table gives reference values, which vary with the pump throughput and
operating conditions.
When the vacuum pump is pumped to below 40 Pa, the oil collected in the oil mist
trap automatically returns to the pump case. The time required for the oil to return to
the pump is more than 10 minutes.
5. INSPECTION AND MAINTENANCE
5.1 Maintenance
Check the following once a day during operation.
(1) Oil leak in the connection with the vacuum pump.
(2) Oil mist or oil gushing out from the case.
(3) Unusual
sound.
If any problem is found, take actions according to Table 6 Troubleshooting Checklist.
5.2 Scheduled
Inspection
Check items should be changed according to the operating conditions of the oil mist
trap, but check the following periodically. Scheduled inspection will serve to
prevent troubles and prolong the life of the oil mist trap.
!
NOTE
Be sure to turn off the power to the vacuum pump before inspection.
Never turn on the power during inspection. The vacuum pump may generate oil mist or
cause injury.
(1) Checking the oil mist trap
If there is an oil leak in the connection with the pump or a large volume of oil mist
or oil gush out from the case, stop the pump and restart it more than 30 minutes later.
If a large volume of oil mist or oil gush out from the case again, replace the element
with a new one.
(2) Scheduled replacement of element
The oil mist separating capacity of the element is limited. Replace the element
before it fails referring to Table 4. Scheduled replacement will serve to reduce oil
mist.
If gas containing dust, dirt water or the like is pumped for an extended time, the
element will be clogged and will not function.
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