4
Cap
8
Coupling I
5
Bore
9
Coupling II
6
Flushing gas pipe
10
Sealing ring
7
O-ring
11
Locking screw
Installing the flushing gas pipe
1. Install the flushing gas pipe from the inside of the cap, and insert it through the bore.
2. Slide the coupling I with the O-ring over the pipe end, and screw the coupling into the cap.
3. Tighten the coupling I lock nut.
4. Align the pipe so that it is positioned close to the cap base, but not touching the wall.
5. Push the coupling II downwards onto the pipe and tighten it. At the same time, secure with a sec-
ond key.
6. Seal the connecting thread with the locking screw and sealing ring.
7. Install the cap.
– Make sure that the sealing surfaces and O-rings are clean and undamaged.
The flushing gas pipe cannot be
dismantled
without destroying it. If necessary, we recommend that
you pull the pipe upwards slightly, and sever it above the coupling with a pipe cutter.
Carry out a leak test.
To make sure that the system is sealed, Pfeiffer Vacuum recommends that you car-
ry out a leak test prior to installing the gas supply.
Carrying out the leak test
In C, M, and MC version pumps, a helium leak test must be carried out after the flushing gas device has
been installed.
1. Carry out a leak test on the pump housing before filling the operating fluid.
– Helium leakage rate: < 1 · 10
-7
Pa m
3
/s
Installing the flushing gas supply
1. Unscrew the locking screw. Simultaneously secure coupling II.
– Be careful with the sealing ring.
2. Connect the flushing gas supply line (female thread, 1/8" NPT).
– Be careful with the seal.
Installation
30/66
