The valve stem of the control valve vibrates severely; how to solve this?
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This post was last edited by zyz8438 on 2010-11-1 10:23. The valve stem of the control valves in our factory vibrates greatly at certain valve positions, and there is also a lot of noise. How can this be resolved?
Reply to 2# kaixuanzz: Okay, thank you. I’ll give it a try first
Reply to 2# kaixuanzz: Hello, where should the noise reduction plates and flow control orifices be installed? ? On the pipe? ? It won’t disrupt the existing balance or settings such as opening degree, etc. ma??? I don’t know how to install it; please teach me
Reply 1# xuyong: Is the set valve position definitely the low valve position? Also, is your valve of the straight-stroke or angle-stroke type? If it’s a straight-stroke valve and this issue occurs only at low valve positions, it’s likely due to insufficient pre-tensioning of the spring! ! Take a look, shall we? Also, make it clear – don’t be so reluctant: lol
This post was last edited by jlszhoujidai on 2010-10-30 at 10:06. It’s possible that the selection of your control valve was inappropriate; the large pressure difference has led to cavitation. It is recommended to use a control valve designed for larger pressure differences~~~
OP, first of all, is the pressure difference before and after the control valve large? If the pressure difference is high and a regular single-seat control valve is used, try switching to a double-seat control valve. If the pressure difference is not significant, it is due to an incorrect selection of the valve; for example, if the CV value is too high, the valve operates at a low opening degree, which causes disruptions in the fluid dynamics and results in increased noise. So, installing a flow-limiting orifice plate about 10D in front of the valve improves the situation.
Recalculate the valve CV value based on the parameters; it’s possible that the valve diameter was not chosen appropriately. Try installing the valve in the reverse direction – sometimes, when the pipe diameter is too large, installing the valve in the opposite direction can reduce vibrations!
Reply 6# wow0011: Is it the spring of the locator? Isn’t that for adjusting the schedule’s zero point?
Reply to 7# jlszhoujidai: Oh, I haven’t thought about that yet. It’s impossible to change it; my boss is poor, hehe
Reply to 10# xuyong: What a great employee! ! By spring, I mean the spring of the actuator, that is, the spring of the diaphragm head, not the regulating valve of a pneumatic actuator. It should be as mentioned above! !
Sometimes this occurs when the valve and piping system are at the same resonance frequency; a slight change in the weight distribution of the valve can eliminate it