Ulvac DIS-90, Instruction Manual

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CAUTION
Danger of exhaust disruption
Remove blank flange from inlet and outlet.
Operation with blank flange being fitted can disrupt exhaust or cause blank flange to fly by
exhaust impetus, resulting in accident, failure, or bodily injury from contact with flying
objects.
Remove blank
flange
Danger of vacuum break and pollution
Be sure to close isolation valve between vacuum pump and vacuum system
(chamber) during start-up and stop.
Start-up or stop with isolation valve in the open position can draw back gas and debris
attached to inside of pump to vacuum chamber due to pressure differential, resulting in
vacuum break and pollution on vacuum chamber side.
Start or stop after
closing isolation
valve
Danger of abnormal sound and failure
Open inlet to atmosphere for about 5 seconds before restarting vacuum pump.
If not, it can unbalance temperature inside vacuum pump, resulting in failure.
Open ai r in let
Danger of exceeding permissible temperature of intake gas
If intake gas temperature is over 50
℃ , be sure to install a chiller or trap
between vacuum pump and vacuum chamber so that gas intake temperature of
vacuum pump keeps below 50
℃ .
If not, vacuum pump temperature can increase, resulting in failure.
Bew are
temperat ure of
intake gas
Danger of remaining moisture
When evacuating moisture, be sure to open air-flush port (air-flush opened
operation).
If you evacuate vapor while air-flush port is closed, condensed water will remain inside
vacuum pump and cause failure.
Operate while opening
air-flush port
Danger of insufficient vapor exhaust
After evacuating vapor, do air-flush opened operation for at least one hour.
If you close air-flush port or stop vacuum pump soon after evacuating vapor, condensed
water will remain inside vacuum pump which will cause failure.
Caution after
exhausting vapor
Danger of exceeding permissible intake gas volume
When sending
N
2
gas or dry air into air-flush port, pressure should be the same
as atmospheric pressure and flow rate should be less than 9L/min.
If not, it can increase pressure inside vacuum pump, resulting in failure.
Beware of intake
gas volume
Risk of motor malfunction
Refrain from frequent start/stop operation.
It induces malfunction of motor such as burn out.
Please consult your distributor or factory representative for details.
Appropriate operating mode with adequate interval and frequency of start/stop is varies
owing to operating condition.
Caution for frequent
start/stop and short
interval
Important
If it takes time to reach ultimate pressure of pump during initial operation (also operation
after pump has not been used for a long time),
Close inlet, and continue operation for 6~8 hours while opening inlet for 3~5 seconds to atmosphere 2~3 times per
hour. During pump stoppage, moisture might have entered inside of pump and deteriorated performance to reach
ultimate pressure.
If pump has evacuated liquid such as water or high humid air (over 60%RH),
Moisture can deposit inside pump and cause pump failure. In that case, close isolation valve, and open inlet to
atmosphere for 3~5 seconds several times and exhaust moisture inside pump to outside.
If pump has continued operation around ultimate pressure or continuously evacuated high
humid gas
Moisture can be condensed and remains inside pump, causing insufficient ultimate pressure and failure.
In that case, do air-flush opened operation in accordance with 4.2 [page 21].