About pneumatic control valves
About pneumatic control valves
(OP)
Can anybody give me any advanced cause about the continuous damage of diaphragms(reinforced) of pneumatic control valve used for boiler feed water? (reverse acting,air quality good)





RE: About pneumatic control valves
You may have more luck with responses.
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RE: About pneumatic control valves
What are the conditions and specifics that apply to your situation?
Also, Ashereng is right that the valve or measurement forum may include more responses. Consider posting with the details at valve engineering.
RE: About pneumatic control valves
rmw
RE: About pneumatic control valves
Regards
Yousuf Ali
RE: About pneumatic control valves
RE: About pneumatic control valves
Now, I'm way out of my field here, a computer guy, but have
a little bit of knowledge in the area. I might suggest that
you incorporate a surge tank in the design to mitigate any
sudden pressure changes which I can envision would be
possible in a feed water system. Such surges in an air
controlled system could easily drive the instantanious
pressure in the system over spec.
Indeed, a small coupon in the circuit can help on the surge
tank can be used with various "delaying" properties easily
changed by choice of coupons on the input side of the tank.
Hope this helps. Again, sorry, I'm out of my area of
expertise, I'll go back and start suffling my "bits" about
again.......
Cheers,
Rich S.
RE: About pneumatic control valves
2. Assuming your valve has a positioner, no boosters and the filter/regulator is set for the correct air supply pressure, the diaphragm should last many years.
RE: About pneumatic control valves
Why not check the supply line to the positioner with a 2nd gauge and see what it reads? Just becuase that cheap little gauge says 50 psi from the regulator it isn't necessarily so.
I'd be curious how the diaphragm failed on a fairly new actuator. Pin hole leak? torn or ruptured fabric? where?
The valve isn't sitting on top of the uninsulated boiler shell at 260°F ambient or some such overlooked possibility?
Dan
RE: About pneumatic control valves