Pfeiffer Vacuum DUO 5 MC, Руководство по эксплуатации, Страница: 18 / 60

periodically as the rotor rotates. This causes the gas to be drawn in at the vacuum flange and com-
pressed in the suction chamber by the rotation of the rotor, until the exhaust valve opens against the
atmospheric pressure at the outlet and expels the gas. The exhaust valve is oil-sealed. When the valve
opens, a small quantity of oil penetrates into the suction chamber. In addition to lubrication, this also
causes the gaps between the rotor, stator and vanes to seal.
Vacuum safety valve
Depending on the pump type, rotary vane pumps are equipped with a vacuum safety valve. This sepa-
rates the rotary vane pump from the vacuum chamber in the event of intentional or unintentional stand-
still, and vents the pumping system with the displaced gas so that oil does not rise into the vacuum
chamber. After switching on, the valve opens after a delay.
Gas ballast valve
The gas ballast device is used to blend ambient air or inert gas with the process gas in the pumping
system. The increase of air content compresses and expels a pumped gas-vapor-mixture within specific
limits, without causing condensation in the suction chamber.
Operating fluid, oil
The pump oil, also known as operating fluid, fulfills various tasks in a rotary vane pump:
● lubrication of all moving parts
● filling part of the dead volume under the exhaust valve
● sealing the gap between the intake and exhaust channel, and between the vanes and the working
chamber
● ensuring an optimal temperature balance through heat transfer
3.3 Product features
Pump type Characteristics
Duo 5 M Standard version with magnetic coupling
Duo 5 MC MC version; differs compared to the standard version by:
● Operating fluid F4
● Magnetic coupling encapsulated on the pump side
● Vane material changed
● Hose connection on the gas ballast valve
● Leakage rate ≤ 1 × 10 -6
Pa m
3
/s
Tbl. 4: Features of the rotary vane pumps
3.4 Identifying the product
► To ensure clear identification of the product when communicating with Pfeiffer Vacuum, always
keep all of the information on the rating plate to hand.
► Observe the motor-specific data on the motor rating plate attached separately.
3.5 Scope of delivery
● Rotary vane vacuum pump with motor
● Operating fluid (other than F4, F5 and A113)
● Centering ring with cone sieve and O-ring for the connection flange
● Locking caps for both connection flanges
● Operating instructions
Product description
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