2
1
8
7
4
3
5
6
Fig. 3:
Functional diagram Okta G
1
Cooling gas connection I
5
Suction chamber
2
Slave rotor
6
Cooling gas connection II
3
Vacuum connection
7
Fore-vacuum connection (fore-vacuum flange)
4
Main rotor
8
Gas cooler
Cooling (optional)
Forced gas recirculation dissipates the heat of the gas, after it has undergone the compression and dis-
charge phases, via a gas cooler on the fore-vacuum connection. As a result, work conditions are ach-
ieved that are not possible with normal roots pumps.
A thermostat switches off the vacuum pump once the pump temperature has exceeded the limit value
(e.g. due to cooling water failure).
Shaft sealed with radial shaft seal ring (RSSR)
The drive shaft feedthrough is fitted with radial shaft seal rings or axial face seals.
The shaft seal with radial shaft seal ring made of FPM is used on standard roots pump versions. Alter-
natively, depending on the process medium, the inner radial shaft seal ring is also be made of PTFE. In
this case the housing seals are also equipped with PTFE covered O-rings.
Shaft sealed with an axial face seal
An improvement in terms of sealing - when pumping aggressive media - can be achieved with the aid of
axial face seals. Axial face seals belong to the seals for fluids and therefore require a supply of a seal-
ing agent and a coolant which are neutral in terms of the medium to be pumped. They offer a sealing
pressure of up to 10000 hPa.
3.2 Product identification
To ensure for a clear identification of the product when communicating with Pfeiffer Vacuum, always
keep all of the information on the rating plate to hand.
The following information is shown on the rating plate:
● Pump model
● Model number
● Type and quantity of the lubricant
● Max. allowable pump rotation speed
● Date of manufacture
● Input voltage range
Product description
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