Washing Area dba to high

[mattski72]

Merry Holidays All!!!

I have a washroom of side loading industrial washer/extractors, nine in all. They are all hydraulically driven and at extract speeds run at 650 rpm. I do not have a frequency profile of the operation nor do I have the means to get one. I need to reduce ambient noise levels between 5 to 7 decibles.

Sound tubes have been suggested as well as sound absorbing mats hung from above.

Having read some of the other posts I get the feeling that more specific data will be required. But I am hoping this will be a good start.

Any help is greatly appreciated.

 

[BrianE22]

We lined the walls of our compressor room with acoustic foam panels. It made quite a difference although I can't give you a dB value.

 

[mattski72]

Thanks Brian.

I think that will work on the area I have a wall. Unfortunately, that only accounts for one forth of the overall set up. "Washroom" is industrial launderers lingo for the location of the washer/extractors. It usually is not a room at all. In my case it is open on three of the four sides. Sorry, one of those things I should have stated up front.

I will considere acoustical foam panels for that wall though.

Thanks.

 

[IRstuff]

You have two choices, either add sound insulation to the machines directly, or put some sort of sound barrier at the nominal boundaries of the "washroom." Even some sort of heavy drapery around the area would probably help.

TTFN

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[mattski72]

Thanks, IRstuff.

I have been looking at hanging quilted fiberglass with vinyl-coated fiberglass cloth on the front side. I can buy it in pre-fabricated pieces and hang it from the structure above. It is marketed as sound attenuating. Any comments on this?

I hesitate insulating on th machine itself though. I am in Florida and the washroom is not air conditioned. It would be something I do in a last effort if other avenues are not fruitful.

Thanks again.

 

[GregLocock]

6 dB is a mighty fine task. You need to eliminate direct radiation paths, get rid of leakage and add absorption, at a rough guess.

Cheers

Greg Locock


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[mattski72]

So, Greg, what you are saying is attack it at its source, right? Makes sense.

Looks like I should start by doing a detailed sound survey of the machines to determine the major contributor. Would my dba meter be adequate for that or would you recommend something else?

Also, I assume a sound attentuating foam would work best if I am looking at direct application to the machine motor and belt housing. Any suggestions there?

Thanks to all for your help.

 

[GregLocock]

If you can't build an enclosure around the washers (and I admit that seems unlikely) then treatment at source is probably the easiest way to get 6 dBA. If you do manage to get 6 dBA then you'll have done a good job.

A dBA meter, and perhaps an accelerometer to plug into it as well, is the bare minimum. I'm guessing the noise is impulsive and chaotic, hence over a wide frequency range. As such you might want to think about a frequency analyser.

Cheers

Greg Locock


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[hydtools]

Perhaps a sound attenuating curtain wall like was done for air compressors per this link:

http://www.enoisecontrol.com/air_compressor_noise_case_study.html

Any barrier material must have mass like lead-loaded vinyl. Simply using fabric or fiberglass will not work. If air can go through, so will sound.

Ted

 

[StrykerTECH]

I would focus on the machine itself. If you can find out where the noise is coming from, i.e. (specific component of the machine, then you can target that)
Is the machine bolted to the floor? Can you Isolate/dampend the machine itself. Can you upload a picture of what it is you are trying to quiet down?

StrykerTECH Engineering Staff

http://www.stryker-tech.com/

 

[SomptingGuy]

I think you need to persuade management to pay for a consultant to come in and sniff around. It's just too hard to describe enough about the environment in words for any of us here to be able to respond usefully.

- Steve

 

[GregLocock]

Good point

Perhaps I should add, just throwing solutions at a problem is a tried and trusted technique, but it is expensive and frustrating.

You really need to accurately characterise the problem, decide what the sound paths are, do the maths on possible solutions, and then implement them. Even then, you'll probably need a second stage of improvements, 6 dBA is a lot, the cure is unlikely to be cheap.



Cheers

Greg Locock


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