Maintenance; Bearing Maintenance - Edwards nEXT730D Instruction Manual

8. Maintenance

WARNING:
When removing the pump, ensure personal protective equipment is used to
safeguard against damage from failed components and possible accumulation of
hazardous material that may have been pumped. Check that the pump is vented to
atmosphere and at a safe temperature. Be wary of possible spillages, sharp edges
and debris. Removal of the pump inlet screen will always expose the risk of injury
from sharp edges.
WARNING:
Allow the pump rotor to stop and then disconnect the motor controller before you
remove the pump from your vacuum system for maintenance or fault finding
procedures.
Table 23 Maintenance

Bearing maintenance

on page 89 The bearing must be replaced when it reaches the end of its serv-
Rotor life on page 90
Cleaning the pump on page 90
Decoding service status words
page 90
Controller run time on page 92
Pump run time on page 92
Pump cycles on page 92
Bearing run time on page 93
8.1 Bearing maintenance
The bearing must be replaced when it reaches the end of its service life. This is typically
after 35,000 hours.
When the bearing needs replacing, Edwards recommends:
B8J200880_D
300812671_002_C3
B8J200880_D - Maintenance
ice life. This is typically after 35,000 hours.
The fatigue life of nEXT Turbomolecular pump rotors is typically
40,000 to 50,000 cycles. As a precautionary measure, Edwards rec-
ommends that pumps are returned for a major service (rotor re-
placement) after 20,000 cycles of acceleration to full speed and
back to a stop, or after ten years of use, whichever occurs first.
If the inside of the pump is contaminated, it may not be possible to
achieve the specified ultimate vacuum performance, or pump-
down times may increase.
on The service status may be accessed directly via the serial link. This
method of accessing service status will give the most complete pic-
ture of current and future service requirements and will allow pre-
ventative maintenance activities to be scheduled.
The run hours and recommended service time of the controller on
the nEXT pump can be monitored.
The run hours and recommended service time of the rotor in the
nEXT pump can be monitored.
The number of start-stop cycles completed and the number re-
maining until the next service is due can be monitored.
The run hours and recommended service time of the bearing in the
nEXT pump can be monitored.
Page 89 08/2021 - ©Edwards Limited