VAT 651 Series - Maintenance Procedures

MAINTENANCE Series
651
74/99 Edition 2014-07-10 605451EC
7.2 Maintenance procedures
Two preventive maintenance procedures are defined for this valve. These are:
• Replacement of isolation seals (gate and body seal of sealing ring) and valve cleaning. Refer to
chapter: «Replacement of isolation seals and cleaning».
• Replacement of actuator and actuator shaft seals. Refer to chapter: «Replacement of actuator and
actuator shaft seals».
•
Required frequency of cleaning and replacement of seals is depending on process
conditions.
• A critical factor influencing the maintenance period is the lifetime of the vacuum
grease, being limited under increased temperature. In this case grease will
separate to PTFE and oil. The oil may flow and contaminate the valve parts.
VAT can give the following recommendations for preventive maintenance:
Replacement of unheated
1)
heated ≤
≤≤
≤ 80 °C
1)
heated > 80 °C
1)
isolation seals
(gate and
body seal of sealing ring)
200’000 cycles 6 months but
max. 200’000 cycles
3 months but
max. 200’000 cycles
actuator shaft seals
1’000’000 cycles
6 months
3 months
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
Plate