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Installation, Operating & Maintenance Instructions
Series 615 DN 40 (I.D. 1.5”), RS485
VAT Vakuumventile AG, CH-9469 Haag, Switzerland
Tel +41 81 771 61 61 Fax +41 81 771 48 30 [email protected] www.vatvalve.com
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2013-02-05
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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 with FKM seals under clean and unheated
condition:
Seals
Maintenance recommendation
Plate o-ring
Exchange a
fter 250‟000 isolation cycles or 2‟000‟000 control cycles
Shaft feedthrough seal
Exchange after 2‟000‟000 control cycles
These values do not include any impact of the process. Therefore preventive maintenance schedule has finally to be
checked for the actual process conditions.