5.10.1 Connecting sealing gas
WARNING
Risk of injury from reactive, explosive or other hazardous gas/air mixtures
Uncontrolled gas inlet of air or gases containing oxygen promotes formation of unexpected explosive
gas/air mixtures in the vacuum system. This results in severe injuries.
► Use only inert gases for supplying the sealing gas supply in order to avoid a potential ignition.
2
1
5
3
4
Fig. 14:
Sealing gas connection
1
Sealing gas connection on the bearing shield (motor side)
4
Gas cylinder (N
2
)
2
Sealing gas connection on the bearing shield (gear side)
5
Pressure reducer
3
Inferential meter with dosing valve
Required tools
● Open-end wrench, WAF 17
● Calibrated torque wrench (tightening factor ≤ 2.5)
Connecting sealing gas
The use of sealing gas in the area of the shaft feedthroughs prevents the contamination of the lubricant
when conveying solvents or reactive gases.
1. We recommend the use of sealing gas as nitrogen (N
2
) or another inert gas.
2. Connect the sealing gas pipe to both connections per bearing shield (4 × G 3/8").
3. Use the gas cylinder with pressure reducer and inferential meter.
4. Set the quantity of sealing gas.
5.10.2 Installing temperature monitoring
To protect the roots pump against thermal overload, a G 3/8" thread for connection of a thermometer
(optional) is provided at the fore-vacuum flange of the roots pump. Pfeiffer Vacuum recommends the
use of a head-mounted transmitter with 2 input channels.
Temperature monitoring
The max. permissible gas temperature in the discharge channel of the fore-vacuum
flange is 140°C.
Installation
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