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ULVAC CRYOGENICS INCORPORATED
11. Maintenance and Inspection
11.1 Daily inspection
Check for the following items for daily inspection.
Pressure gauge reading record; below the pressure of 0.028MPa.
Level gauge record
The operation sound generated from each unit is normal.
The pressure and flow rate of nitrogen gas are 0.2 MPa and 20NL/min.
respectively.
He gas pressure of UW701N is within appropriate range.
When in operation:
1.90 – 2.30 MPa
The alarm light of MP-300K is off.
11.2 Maintenance/inspection intervals
Parts
10,000Hr
30,000Hr
40,000Hr
1 year
2 years 5 years
Coldhead cylinder
(2 units) *1
Adsorber (Compressor)
Helium line coupling
GN-20i air compressor
GN-20i filter *2
GN-20i solenoid valve *3
Check the total operation time of the system with the hour meter on UW701N.
*1…
Maintenance interval is normally 10,000 hours, however, even if 10,000
hours is not reached, replace them once every 5 years as the internal parts
may become deteriorated.
NOTE: When replacing the oil adsorber, it is requested to return the used set to us
after replacement.
*2
Clean the filter on the air intake port of GN-20i every month.
*3
Maintenance cycle differs depending on the frequency of operation.
In case GN-20i is operated continuously, the solenoid valve should be
replaced every two years.
