Ulvac UTM3400 Series, Instruction Manual

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8.2 Turbo Molecular Pump Decontamination
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8
8.2
Turbo Molecular Pump Decontamination
All expenses incurred with the decontamination of the turbo molecular pump are the
responsibility of the customer.
8.3
Touch-down Bearing Replacement
The touch-down bearing (Fig. 3-1 (8)) is the only component of ULVAC's turbo molecular pump
that is subjected to friction and wear, normally occurring only during electrical power failure.
Repeated and/or frequent rotor touch down will cause wear and bigger rotational resistance and
require replacement of touch down bearings.
The replacement of the touch-down bearing is done only by ULVAC or an approved service
company.
8.4
Check of the Rotor Blades
Rotor blades of turbo molecular pump are high-speed rotor made of aluminum alloy. It has the
possibility that material strength deteriorates, specially when corrosive gas is evacuated. Regular
check (Customer is liable for the cost.) by ULVAC or a ULVAC approved/authorized service
center is suggested. (Every one year is recommended.) ULVAC and/or the service center
investigate rotor blades in every overhaul task and check and suggest a rotor replacement to
customers if any cracks are found out.