Ulvac PRC-003A Instruction Manual page 39

⑥ In the case of the process flowing combustible gas/susceptibility of
substances to burn gas, you are requested to introduce the diluent
gas.
Flow the diluent gas from the intake side so that the gas
concentration to be exhausted becomes lower than the explosion
limit.
If the pipe connected to the outlet had a small diameter or attached
foreign substance inside, it might raise the pressure inside the pipe and
impair the pump operation. A caution shall be required.
There is a risk that the pressure inside the Vacuum pump rises up to
cause break or oil leak of the casing or Oil level gauge resulting in
WARNING
overload of the motor.
① Wash sufficiently inside the Vacuum chamber, pipes, Vacuum valve
and so on to connect them to the Pump. If dirty unit were connected,
it would cause a trouble such like raise the ultimate pressure or
extend the depression time to the specified pressure. Wear a pair of
gloves to touch any vacuum section. Do not touch with the bare
hand.
② Pay attention not to give damage to the Flange sheet face, Gasket
slot or gasket itself.
CAUTION
③ Use a pipe having bellows between the backing pump and outlet of
the Mechanical Booster Pump so as to avoid any direct load to the
Pump flange.
④ Do not connect directly the backing pump inlet with the outlet of the
Mechanical Booster Pump.
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YO99-0874-DI-002-18