Series 65  MAINTENANCE 
 
963283EA  Edition 2019-05-03  105/
 
7.2  Maintenance procedures 
Two maintenance procedures are defined for this valve. These are: 
• 
Replacement of isolation seals (gate and body seal of sealing ring) and valve cleaning 
• 
Replacement of actuator shaft seals 
 
 
 
Required frequency of cleaning and replacement of seals is depending on process 
conditions. 
VAT can give the following recommendations for preventive maintenance: 
 
Replacement of  unheated 
1)
 
heated 
≤
 80 °C 
1)
 
heated > 80 °C 
1)
 
 (gate and 
body seal of sealing ring) 
12 month but max. 
200’000 cycles 
6 months but 
max. 200’000 cycles 
3 months but 
max. 200’000 cycles 
 
 
 
 
 Those figures are reference values for clean conditions under various temperatures. 
These values do not include any impact of the process. Therefore preventive maintenance 
schedule has finally to be checked for the actual process conditions. 
 
 
 
NOTICE 
Vacuum grease 
Vacuum grease may be distributed and contaminate the valve. 
Prevent gap between body and sealing ring from air gun cleaning. Do not clean the 
gap between body and sealing ring with compressed air. 
 
See figure below: 
 
 
 
 
 
Body 
 
 
 
Gap 
 
Sealing ring