You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
www.pfeiffer-vacuum.net<br />
This results in lower power consumption, quiet operating, uniform temperature distribution<br />
within the pump and low cooling water consumption. This makes these pumps extremely<br />
cost-effective, in spite of their robust design.<br />
Figure 2.9: HeptaDry rotors<br />
2.5.2 Application notes<br />
In recent years, screw pumps have been replacing oil-lubricated rotary vane pumps in the<br />
high pumping speed segment (100 – 600 m3 / h)<br />
Their advantages include:<br />
No lubricant in the gas displacement area<br />
No contamination of the medium to be pumped<br />
Higher efficiency thanks to internal compression<br />
Lower ultimate pressure p B < 10 - 1 mbar<br />
Virtually constant pumping speed between 1 and 1,000 mbar<br />
Good liquid and particulate matter tolerance<br />
Bearings and seals are protected through low gas pulsation as a result<br />
of internal compression<br />
High-quality axial face seals<br />
Low noise level thanks to standard-feature silencers and outlet valve<br />
Temperature-regulated cooling<br />
Low energy consumption<br />
Extensive use of standard components<br />
Mounted ready for connection on a frame with vibration dampers<br />
Ideal backing pump for Roots pumps<br />
This makes HeptaDry screw pumps very well suited for chemical applications or processes<br />
that generate dust, e.g. for semiconductor production, or if significant volumes of condensate<br />
are produced.<br />
Page 43<br />
<strong>Vacuum</strong><br />
<strong>Technology</strong>
Change language