anybody have any input on compressed air dryers? I need to pull the water out of the air lines and the cheapo Desiccant isn't cutting it.

How much air? Application? Piston or screw? Aftercooler on compressor? Dew point required?

[This message has been edited by txaggie02 (edited 9/21/2012 11:38p).]

As in an air dryer on an air compressor?

Media Blast Cabinet and small spray on finishes.

Piston in an unregulated environment.

I know we run them at the shop to prevent moisture from getting into the machines, but I won't be able to tell you what we use until Monday.

Downstream of the air compressor to remove moisture. Almost 100% of industrial air compressors have either a refrigerated or desiccant dryer downstream. Water isn't good in production equipment or the final manufactured product in a large majority of applications.

[This message has been edited by txaggie02 (edited 9/22/2012 12:20a).]

can't call tonight. everyone in the house is asleep but will call tomorrow and leave a message.


I am just looking for a good quality desiccant as I don't think I can afford a refrigerated unit.

Desiccant isn't going to work if you keep dumping oil onto the desiccant beads. Piston compressors pass a lot of oil downstream which will prevent your beads from being able to absorb water. Also, if you don't have a compressor with an aftercooler, the air will be too hot for desiccant beads. If you are just using desiccant filters and not dryers, you will be replacing them all the time as they are crappy. No way the purge the beads.

If you have a piston compressor without an aftercooler, you need a high-temp refrigerated dryer.

If you have a piston compressor with an aftercooler, then you need a standard refrigerated dryer.

[This message has been edited by txaggie02 (edited 9/22/2012 12:29a).]

What if it is 25 feet or so for the compressor with a trap before it?

so either way I am spending $500+ on a system..

25' is short compared to most facilities I've installed. I don't know how exactly much you are looking at since I don't know how many cfm you are using and at what psi.

[This message has been edited by txaggie02 (edited 9/22/2012 12:39a).]

But yes, more than $500.

Very basic system.

Compressor:
Manufacturers Number: VT6355
Brand: Campbell Hausfeld®
Tank Capacity: 60 gal.
PSI Rating: 135 Max PSI
Flow Rate: 11.8 SCFM @ 40 PSI, 10.2 SCFM @ 90 PSI
Power Rating: 3 HP
Length: 27 in.
Width: 30 in.
Height: 71 in.
Material: Steel
Voltage Rating: 230 V


Blast Cabinet:
37-1/8"W x 23-5/8"D x 22-1/2" H work volume
Clear reinforced media tube connects to bottom of hopper
Foot operated control switch
Large side load doors
Self-contained dust collection system with cartridge filter and convenient bottom gate clean-out
Heavy-duty blasting gun
Overhead, stationary blasting nozzle
Door-ajar switch keeps work environment safe
125 Max. PSI @ 5-25 CFM
16 Ga. cabinet panels
14 Ga. legs
Powder coat paint
Approximate shipping weight: 231 lbs.


Plus HVLP/airbrush paint booth and basic tools

I use a Harbor Freight refrig dryer on a compressor a bit larger than yours. This feeds all of our shop, but we needed the dryer specifically for a plasma system. It is cheap and we have to babysit it some because it doesn't always want to let-off the collected water, but it works. Surprisingly, it has lasted over 2 years now. If you absolutely cannot spend more, this might be an option (this was my case). We tried desiccants before this and nothing ever worked.

http://www.vanairsystems.com/

Check these guys out. We represent them here in Texas. They make high quality stuff at decent prices. They also have technical support staff who can help you spec in exactly what you need.

Send me a message if you would like help.

I have this one on my compressor. Actually a previous version. I have used it for blasting, automotive painting and general air tool use with no problems.

http://www.sears.com/craftsman-heavy-duty-air-line-filter/p-00916009000P?prdNo=6&blockNo=6&blockType=G6

If you're a DIY kind of guy, check out options like this.

http://www.dune-buggy.com/webs/Off-Road_Buggies/todd_kirkwood/compressor.html

I am just trying to figure out if I had 3 or 4 of the cheaper Desiccant if it would work well......

Unless you have a desiccant DRYER and not a desiccant FILTER, then you are wasting your time and money. Even if you have a dryer and the temp is too hot or you are passing oil downstream, then forget it. It will ruin the desiccant and quit absorbing water. Trust me on this.

If you stack 3-4 filters, you will need to account for 10-12 psi of pressure drop too.

Understand that a desiccant dryer is for critical applications (pharmaceuticals, chemicals, food industry, semiconductor, etc) where a -40 degree dew point is required. That's not what you are looking for.

[This message has been edited by txaggie02 (edited 9/22/2012 4:47p).]

Can't you easily remove oil from the air by using a coalescing filter?

Yes, you can use a high temp filter (since there is no cooler on the compressor) but how are you going to purge or dry the desiccant in the filter? The dryers use some of the dry air to purge the desiccant in the other chamber. A filter doesn't. Those filters suck.

Hell, buy a used refrig dryer. Anything but those filters.

[This message has been edited by txaggie02 (edited 9/22/2012 5:28p).]

quote:

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Can't you easily remove oil from the air by using a coalescing filter?

---

Yes, and the Ingersoll Rand ones come with float type drains to remove the moisture from them. If you don't care for the floats, you can replace them with timed electronic solenoid drains.


With the appropriate filters, there's no reason you cannot use a desiccant dryer with a recip compressor, but as stated earlier, the compressor must have an aftercooler.

Look, why would you spend more money on a desiccant dryer (plus a coalescing filter) that isn't needed for the application? You guys are making this WAY too difficult. Going from 36 degree dewpoint on a refrig dryer to -40 degrees on a desiccant dryer doesn't come at no additional cost. RB, do whatever you want to do. Whatever route you go, I will strongly recommend you check the equipment for max inlet temp compared to your compressors discharge temp. My recommendation to you is to buy a high inlet temp refrig dryer.

[This message has been edited by txaggie02 (edited 9/23/2012 12:48a).]

How often do you drain the receiver? They need to be drained regularly either manually or automaticaly. If you don't do this it doesn't make any difference whether you use any of the above mentioned dryers or not you are going get water in the lines. Is there a filter/regulator at each station?

As most will agree, desiccant FILTERS are rubbish. It's a waste of money.

Install a refrigerated air dryer. If your compressor doesn't have an after-cooler, get a high temperature rated dryer.

Desiccant dryers are used for special applications, like in hospitals or breathing air. If you do however decide to install a desiccant dryer, make sure to install a oil filter (coalescing filter) before it. Oil will ruin the desiccant in no time! Also, install a dust filter after the dryer to remove any desiccant particles.

Again, refrigerated dryers are much cheaper and better suitable for this application. Condensate water would normally be automatically be discharged by an automatic drain.

All you ever wanted to know about compressed air dryers can be found here: http://www.air-compressor-guide.com/compressed-air-dryer.html

Make sure to click through to the pages about desiccant dryers and refrigerated dryers.

Also, check that the drains (on your air receiver, on your dryer, etc) regularly. They are often full of dirt and stop working because of that..

[This message has been edited by air-compressor (edited 10/30/2012 4:19p).]

Depending on what the OP is trying to do,you guys might be trying to over sell the OP.

I am running a similar setup to what the op has.

For blasting, I have something similar to the craftsman filter at the compressor. If it is super humid and I am running it a lot, I will notice some moisture coming through the line but as long as it isn't enough to clump the beads, I don't care.

When I pull out the HVLP guns, I will add another regulator and a second air hose between the compressor and a disposable filter attached to the gun. It works well. I have been happy with the quality of finishes I have put down. Granted I have not tried to paint a car but equipment and machines have been fine. You would never produce a 100 point show car like this but then again, you probably don't have the talent and experience to do that anyway.

The idea behind the second regulator and hose is to let the air get as at as low of a pressure and as cool as possible before it goes through the second filter. I want it coming out of the second filter (and into the gun at around 20-25 psi, so that I am getting 8-10 at the tip.

it looks like this

compressor
|
regulator
|
filter
|
|
|
air hose
|
|
|
regulator (used to control air flow)
|
|
|
air hose
|
|
|
|
disposable filter
regulator (just used as an air gauge)
HVLP Gun