Agilent Technologies TPS-mobile 9698403, Руководство пользователя

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17 Technical Information
Description of the TPS mobile
342/400 TPS-mobile User Manual / 87-901-005-01 (F)
1 – Turbopump Description
The turbopump consists of a high frequency motor driving a turbine
fitted with many bladed stages and Twistorr drag stages. The turbine
rotates in an anticlockwise direction when viewed from the high
vacuum flange end.
The turbine is made of high-strength, light aluminium alloy, and is
machined from a single block of aluminium. The Twistorr stages are
in the form of discs.
The turbine rotor is supported by permanently lubricated high
precision ceramic ball bearings installed on the forevacuum side of
the pump.
The static blades of the stator are fabricated in stainless steel. These
are supported and accurately positioned by spacer rings.
The TwisTorr stators are in the form of selfpositioning machined
disks. On each disk there are parallel spiral pumping channels
designed to pump in centrifugal direction on one side and in
centripetal direction on the other side. These are made of aluminium
alloy.
During normal operation, the motor functions with a power feed at
54 Vac three-phase at 1167 Hz (74 FS), 1010 Hz (304 FS) or 700 Hz
(TV551). To reduce losses during start-up to a minimum, the
frequency increases according to a ramp with a higher initial
voltage/frequency ratio.
A thermistor sensor is mounted near the upper bearing to prevent
the pump from overheating.
The pump is balanced after assembly with a residual vibration
amplitude less than 0.01 µm.