Ulvac DIS-90, Instruction Manual

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3.3 Connection to vacuum system (chamber)
Inlet is NW25 and outlet is NW16.
CAUTION
Danger of exhaust disruption
When connecting exhaust piping to vacuum pump and when combining piping
with another vacuum pump, pay attention to piping size and length so that it does
not cause exhaust resistance.
Exhaust resistance can disrupt air flow, resulting in failure and over-current.
Pay attention to
exhaust resistance
Important
Use isolation valve between vacuum system and inlet.
Isolation valve is necessary to prevent the drawback of debris attached to the inside of vacuum pump into the
vacuum chamber during start-up and shut-down. (We recommend the use of leak valve also). We recommend the
use of an
automatic valve as the isolation valve which closes during power failure in order to prevent
the drawback of debris inside pump into the vacuum chamber during power failure.
Use the clean connecting pipe between vacuum chamber and vacuum pump.
We recommend the use of a flexible tube between inlet of vacuum pump and vacuum chamber so that vibration of
pump does not transmit to vacuum chamber.
When connecting exhaust piping to outlet of vacuum pump, refer to the following size and length.
・ max. 30m direct pipe length for exhaust pipe size NW16 (inner dia.16)
But if pipe length becomes longer, use a larger size exhaust pipe.
Make sure that exhaust piping is not clogged during pump operation.
Make sure that pressure at outlet does not exceed atmospheric pressure at any conditions.
In order to keep condensation away from feeding into the exhaust port, take proper measure.
It causes exhaust disturbance. Drain condensations periodically by using valve separately arranged.
Chamber
Isolation valve
(Automatic valve)
Leak
valve
Vacuum pump
Outlet duct
Inlet Outlet
DIS-90
Drain
condensation