Replacing The Diaphragm - GF 514 Betriebsanleitung

Operating Instructions
7.3

Replacing the diaphragm

The frequency for changing the diaphragm depends on the number of actuator cycles and the medium used. The diaphragm can be
checked by professionally disassembling the upper part.
NOTE!
The diaphragm is a consumable part!
With heavy usage the diaphragm is excessively worn and needs to be changed more frequently. Worn or damaged diaphragms can
cause personal injury or property damage.
► Diaphragms and gaskets should be checked and replaced depending on the load and intensity of use.
► Only replace the diaphragm that is compatible with the valve according to the type plate.
CAUTION!
Replacing the complete diaphragm set!
If PTFE diaphragms with EPDM or FKM are used then both diaphragms must be changed.
► Make sure that both diaphragms are changed.
1. Depressurize and empty the pipe.
2. Move valve to "OPEN" position.
3. Carefully unscrew the housing nut using a strap wrench (available separately).
CAUTION!
Incorrect tool for housing nut!
The use of incompatible tools can damage the housing nut. Escaping medium can cause personal injury and damage to property.
► Only open and close the housing nut with a strap wrench or hook wrench.
4. Make two turns with the handwheel while fixing the inner housing to release the diaphragm from the inner housing. Fix inner
housing and remove diaphragm from inner housing by turning counterclockwise.
NOTE!
Position indicator pin breakage!
If the spindle assembly is completely turned out via the handwheel, the position indicator pin may break. This means that the valve
position can no longer be displayed.
► Only make a maximum of two turns of the handwheel to detach the diaphragm from the inner housing.
► If the position indicator pin breaks, it must be replaced.
Diaphragm valve type 514, 515, 517, 519
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