How to silence compressed air blasts

I started using a compressed air dryer. This dryer, as part of the operation, opens a valve every minute or so for a couple of seconds.
(it is my strong opinion that I should try to find a way to make it do so less often, but I digress).
This valve opening produces a very annoying noisy blast of air. To combat this, I routed the polyethylene tubing to the outside of the building, by drilling a hole in the masonry.
This "resolved" the problem by moving the blast from the inside to the outside. The outside is the back of the building and faces the railroad. So it is not bad. But, I would like those blasts to be quieter on the outside also. What can I do, realistically, to silence them?
i
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One or two of these will work:
http://www.ebay.com/itm/SMC-AN302-03-3-8-Pump-SILENCER-/150975096358?pt=LH_DefaultDomain_0&hash=item2326d12626
Best Regards Tom.
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That _style_ will work, but those are not large enough mufflers to serve the high pressure lines he's got.
Those are better as cylinder relief mufflers. Relatively low volume, relatively low pressure.
For point of reference, one about the size of the muffler on a small lawn mower would be about right -- say about 2" diameter and 5-6" long.
Common as dirt -- McMaster, Bailey, MSC, Adams Air... just about any pneumatic/hydraulic supplier has 'em.
LLoyd
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Ignoramus24985 wrote:

Well the cheap way is to simply run the end into a common turbo style car muffler. (not a straight through type) That is what we had in both shops.
There should be a sensor that trips the purge cycle based on collected water. Some use a humidistat as well.
--
Steve W.

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wrote:

Most use a simple timer.
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On Thu, 17 Jan 2013 23:20:48 -0600, Ignoramus24985 wrote:

...

Routing the blast of air through a baffle box would help. See eg <http://physics.stackexchange.com/questions/28441/can-sound-be-separated-from-air and <http://wiki.diyfaq.org.uk/index.php?title ffle_box> for some discussion, and also look for "sound baffle box" (without quotes) on google images. As shown in some pictures, the surfaces in a baffle box should have sound-absorbing stuff (eg fiberglass insulation) on them. The box could be outside, eg a tall thin box fastened to wall, with exit opening pointed down.
--
jiw

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On Thu, 17 Jan 2013 23:20:48 -0600, Ignoramus24985

Put on a muffler of course!
Gunner
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message

Perhaps a pipe-threaded lawnmower muffler would help?
I found a bin of air exhaust silencers similar to this in a second-hand store and use one on my vacuum pump: (Amazon.com product link shortened) The porous material inside resembles that used on chainsaw intake filters. The thread is more likely 1/4" NPT than 4".
I just tried it. While it doesn't "silence" the loud pump outlet it's quite effective for the price. It drops the sound level from 92 to 82dB and removes the annoying buzz from the vanes. jsw
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On Thu, 17 Jan 2013 23:20:48 -0600, Ignoramus24985

Run the blast through a tapered cone, up to about 2 or 3 inch diameter, and run that (enlarged) pipe up above roof level and discharge across the roof. The lowered velocity will decrease the noise significantly, the larger pipe will lower the pitch, and the height will dispurse the sound.(and attenuate it)
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On Jan 18, 12:20am, Ignoramus24985 <ignoramus24...@NOSPAM. 24985.invalid> wrote:

I would try routing the blast of air into a 30 lb propane tank with a tee on the tank so that the inlet has no restriction but have a valve on outlet that lets the air out slowly. The tank needs to be mounted so water does not accumulate in the tank.
Dan
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