Quieting the operation of a hydraulic valve?

[ryandias]

Currently we are testing some equipment under hydraulic load using a valve as the load.

It is generating a lot of noise that is for lack of a better description, BUGGING everyone!

Anyhow. They system is running kind of hot. Any suggestions as to how we might quiet the operation of this valve? I suggested Pink insulation (I know there is a noise reduction type) losely around the valve.

It is generating a higher pitch squeeling noise.

From what I see online, The choice of valve should have been made with the noise in mind. But an electrical guy made the selection

 

[ScottyUK]

You'll find a better forum at forum1083. Sorry I can't be of any more help.


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Sometimes I only open my mouth to swap feet...

 

[IceStationZebra]

Anytime you drop pressure you are converting hydraulic energy to heat, noise and sometimes work. You can't get away from that fact. The best solution would be to get a proper pressure reducing valve.

I would be a little cautious with the "pink" insulation. It will become saturated with oil and pose a fire hazard. You should be thinking more like a wooden or plastic box with-in a box with some type of foam (ideally lead lined) in between with an air gap. The biggest problem here is that the sound will still be transmitted by the hydraulic lines on either side of the valve. So how much can you put into the box?

The machines that I deal with generally use 95+% hoses. But from what I have read the best solution from a noise perspective is a steel line with short pieces of hose on either end.

ISZ

 

[automatic2]

Audio is a byproduct of work. We use Dynos as our load, and we wear earplugs under earmuffs. I am going to guess that your 'load' is a pressure relief valve. Try submerging your valve in a bucket of hydraulic oil.

 

[KENAT]

automatic2, I nearly suggested earplugs under earmuffs.

The 'sound box' per IceStation sounds like a good idea, my only thougt is whether heat is an issue in your particular application?

If your valve is generating any significant heat while in operation you need to take that into account.

 

[ryandias]

It is generating some heat. I looked at the setup and a smaller bucket of oil might be possible to immerse the valve in.

I figure the oil will just aide in heat dissipation.

 

[KENAT]

Hmm, don't sound waves normally travel better through liquid than gas?

Isn't that why whales can be heard so far off and sonar works better under water than in the air?

That said as a kid we used to muck about trying to speak under water and I recal it damping the noise so maybe it is a good idea.

The forum scotty posted might be the way to go.

 

[JOJOMO]

Kenat,

I had a similar discussion this week about sound traveling better in a liquid. At first, I argued that it would travel better due to the sonar argument.
Then, I thought about myself talking under water and remembered that you can't hear worth a flip far away and convinced myself that the opposite is true. Now, I wonder if that is due to the production of sound by the mouth underwater, or the ability of the ear to work underwater.

 

[zeusfaber]

Sound travels really well underwater - the trouble is getting it to cross the air/water interface in either direction.

Immerse your eardrum in the water and you will hear someone hammering away underwater on a lump of metal a hundred yards away as if they were right next to you. Put a hood over your head and blow a little air into it, and you probably won't hear it at all.

It's all about impedance matching (which essentially boils down to differences in the speed of sound between the air and the water).

With this in mind, I wonder if there's any mileage in putting some other liquid in the bucket (perhaps something denser and more viscous than hydraulic oil) and maybe doing a hard pipe to hose swap before the pipes emerge from the bucket.

A.

 

[KENAT]

zeusfaber, you're right, it got me thinking and I figured getting it to cross the gas/liquid barrier would reduce the noise.

JohnJMoody

Nominally sound does travel better in water than air but crossing the barrier causes a problem. In fact If I recall things I've read about sonar the same can happen with different densities of water due to variance in temperature/salinity.

 

[meintsi]

<<< Currently we are testing some equipment under hydraulic load using a valve as the load. >>>

Are you testing a pump? and for what characteristic?
What kind of valve are you using for the load?
Where is the load valve installed?
GPM and Pressure? Fluid?
Valve and connection characteristcs?

In other words, we need the details.............

Remember...
[navy]"If you don't use your head,[/navy]
[navy]your going to have to use your feet."[/navy]