Translation of the original operating instructions
Type 327
© 1994 - 2022 SED Flow Control
62
BA220002 Version:
a
Vo
rl
ag
e
: d
o
k360 (
c)
6.2. Diaphragm change
The diaphragm has to be controlled for wear after max. 100.000 (≥MA80 50.000) switching
operations. Depending on working load, the control period has to be reduced according to valid
regulations and rules.
Particles in the working media can be abrasive
–
reduce control period accordingly.
Only use diaphragms which are suitable for your application.
Don’t use higher control pressure than necessary. This helps to save the diaphragm.
Notice
Media leakage by wrong assembly!
Ensure correct assembly before startup!
Danger
Danger of injury through high pressure!
Pressure acting on lines and valves may cause severe injuries!
Before disconnecting any lines and valves, the pressure must be switched off and the lines must be vented.
Protect the facility from inadvertent operation!
Danger through media leakage (steam, hot media, acid, lye)
6.2.1. Change of one-piece diaphragms
→
Disassemble valve, see chapter 5.3.2.
→
Bring valve in close position.
→
Screw out diaphragm
anticlockwise (≥MA10).
→
Insert compressor and position it correctly.
→
Screw in diaphragm by hand up to the stop or respectively plug it in. Then position diaphragm
by turning it back anticlockwise in a way that the wholes of the diaphragm and valve body fit
together. Attention! Do not turn back more than 180°! Also take care for correct position of
the diaphragm flap. If the diaphragm isn’t assembled correctly, point loading can occur! This
can lead to leakage and damage of the diaphragm.
→
Bring valve in open position.
→
Place actuator on the valve body. Take care for correct orientation of diaphragm and weir.
→
Position screws and fasten hand-tight.
→
Close pneumatic actuator.
→
Fasten screws or nuts crosswise.
→
Tightening torques see chapter 5.3.1.
→
Check the valve at the pass and to the outside for tightness and function. Take care for equal
compression of the diaphragm
–
about 10% depending on material and version. Especially
PTFE diaphragms show a setting behavior. Check the valve after the first thermal load latest
and re-fasten screws if necessary.
