LEYBOLD TURBOVAC TW 250 S, Руководство по эксплуатации

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Connections
19
GA 05137_1102 - 12/2003
2.3 Forevacuum connection
As forevacuum pump we recommend using the dry
compressing ECODRY M15 piston pump or a TRIVAC
two-stage rotary vane vacuum pump, e.g. the D 2,5 E.
Connect the clean forevacuum line; see Fig. 9. The
connecting flanges must be clean an undamaged. The
cross section of this line must be so wide that safe ope-
ration of the pump can be ensured.
Remove the three screws and the clamping yoke.
Remove the shipping flange.
Slide the KF flange from the forevacuum line onto the
centering ring, slide the clamping yoke over the flange,
insert and tighten the three screws.
Warning
The forevacuum line must be tight. Hazar-
dous gases can escape at leaks or the
gases being pumped can react with air or
humidity.
Figure 14 is a schematic diagram of a pump system
incorporating a turbomolecular pump and a TRIVAC
forevacuum pump with an anti-suckback valve.
A separate safety valve is provided for oil-sealed foreva-
cuum pumps without an anti-suckback valve. The safety
valve prevents oil flowing back from the forevacuum
pump into the turbomolecular pump when the system is
not running.
To ensure that the forevacuum space at the turbomole-
cular pump is kept largely free of oil vapors during ope-
ration, as well, we recommend installing an adsorption
trap in the forevacuum line. An adsorption trap is not
required when using a dry compressing forevacuum
pump like the ECODRY M 15, for example.
Provide a roughing line to achieve the shortest cycle
times.
Ensure that the pump is sufficiently isolated against
resonances (vibrations) generated by the forevacuum
pump.
1 Clamping yoke
2 Screws
3 Centering ring
4 KF flange from
the forevacuum line
Fig. 9 Connecting the forevacuum line