Modern analytical methods like electron microscopy and mass spectrometry require extremely efficient and reliable components, and often involve suction rates of up to 2,000 l/s. In order to achieve such high performance, HiPace Turbopumps from Pfeiffer Vacuum are employed in combination with a rather special magnetic bearing system. Here, the rotor is protected against atmospheric influences by an RSG solenoid valve. At the end of the process, the valve is opened and the pump is flushed with gas for a predefined period of time. At the same time, the rotor speed of 15,000 rpm is slowed down. Of course, this rotor braking must not be an uncontrolled process, as this would otherwise shorten the operational life cycle of the pump. The requirements in this case were correspondingly demanding:

• Leakage rate testing up to 10^ –8 mbar l/s
• Low power-input requirements
• Compact size
• Comprehensive testing

A product solution to meet the highest standards was successfully developed in close partnership.