Technical Information; Description Of The Turbopump - Varian Turbo-V70LP Manual De Instrucciones

DESCRIPTION OF THE TURBOPUMP

The Turbo-V70LP pump is available in four ver-
sions. The difference between the two versions
lies purely in the high vacuum connection. The
four versions are:
− Model 969-9365 with ISO 63 high vacuum
flange
− Model 969-9366 with ConFlat 4.5" external
diameter high vacuum flange
− Model 969-9367 with KF 40 NW high vacuum
flange
− Model 969-9368 with ConFlat 2.75" external
diameter high vacuum flange
Model 969-93651
Model 969-9367
The Turbo-V70LP pump consists of a high fre-
quency motor driving a turbine fitted with 10
bladed stages and 4 Macrotorr stages. The turbine
rotates in an anticlockwise direction when viewed
from the high vacuum flange end.
Model 969-9366
Model 969-9368
The turbine is made of high-strength, light alumin-
ium alloy, and is machined from a single block of
aluminium. The turbine blades have five different
angles, from 44° to 12°, while the Macrotorr stages
are in the form of discs.
The turbine rotor is supported by permanently lu-
bricated high precision ceramic ball bearings in-
stalled on the forevacuum side of the pump.
The static blades of the stator are fabricated in
stainless steel. These are supported and accu-
rately positioned by spacer rings.
The Macrotorr stators are in the form of self-
positioning machined discs with pumping channels
and an opening restricted by the corresponding
rotor discs. These are fabricated in aluminium al-
loy
During normal operation, the motor functions with
a power feed at 54 Vac three-phase at 1250 Hz.
To reduce losses during start-up to a minimum,
the frequency increases according to a ramp with
a higher initial voltage/frequency ratio.
The external body of the pump is fitted with fins
which allow the pump itself to function with natural
convection air cooling. Kits are available for water
cooling or forced air cooling to cool the pump in
the cases where it is used under heavy load or
when natural convection is insufficient for cooling
purposes.
A thermistor sensor is mounted near the upper
bearing to prevent the pump from overheating.
The thermistor sensor, the motor stator windings
and the earth are connected to a Turbo-V control-
ler through a 6 pin socket on the side of the pump.
The pump is balanced after assembly with a resid-
ual vibration amplitude less than 0.01 μm.
The pump can operate in any position and can be
supported on the high vacuum flange or on its
base. The connection of the forevacuum on the
side of the pump is a KF 16 NW flange.
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TECHNICAL INFORMATION

87-900-862-01(G)