Setting up air dryer/filters

[corvairdad]

I bought a twenty-some foot long coil of 3/4 copper as the basis to get cooler, drier air. When I'm painting or blasting, I fill the tub with water and drop a couple blue ice packs in to keep the water cold.

 

[swharris]

Don't forget the disposable filter at the gun. Cheap insurance.

 

[TLCDino]

I think the use of the copper zig zag system is over rated.
If you simply use a some large copper pipe (2" or 3") in a two foot verticle set up with ability to enter this pipe from middle and exit out the top to the main run. the large copper pipe would come just after the air left the compressor tank. This air will be warm and with the pressure drop into the large copper pipe it will cool down thus dropping out liquids into the bottom of the pipe. cooler dry air will exit out the top and into the main run. Have a drain on the bottom of the larger pipe to remove liquids periodicaly.
I this set up and it works great. Simple, effective, and less space.

How exactly does the "cooler dry" air go out the top while the hot air stays at the bottom? Have you ever seen how those huge people carrying balloons use hot air to rise?

 

[pcmeiners]

Not sure it was mentioned...
Copper is a good conductor of heat but a very poor radiator of heat as compared to steel, that is why old radiators were cast iron and the new radiators have aluminum fins. For a cooler, on the technical side black pipe would be the way to go, on the practical side copper is so much easier. I checked Ebay/craigslist could not find a decent priced cooler.

 

[brats.n.harleys]

heres mine, made out of a 2 gal. compressor tank. the bottom bung was existing, welded the top one on. Has 10 pounds of desicant in it. every 6 months or so, i unscrew the top fitting, and lay all the desicant out on a cookie sheet and let it dry out for a few days, til its blue again.

 

[CARS]

heres mine, made out of a 2 gal. compressor tank. the bottom bung was existing, welded the top one on. Has 10 pounds of desicant in it. every 6 months or so, i unscrew the top fitting, and lay all the desicant out on a cookie sheet and let it dry out for a few days, til its blue again.

That is a great idea but I wonder what holding all the moist desicant will do to the metal in the tank? May not be a issue for quite some time.

I have to think about things like this because my air system gets inspected by the state every 2 years. 4 years ago they condemned my air compressor's tank. They use a sonic tester to determine the metal's thickness. The tank was dated 1948, so I wasn't surprised.

 

[Vicegrip]

It does not get moist. I have one made from an old steel scuba tank. Desiccant filters rock. Nothing gets the air as dry as a desiccant filter.

 

[1931S/X]

i dont really think it matters what material the cooling run is made out of, its the distance or time the air travels allowing it to cool and be separated. my small compressor, my dad gave me its about a 20 gallon, he used to wheel it around the warehouse to the car and put it away at night. he always had a filter water separator and regulator right on the compressor, when he gave it to me i noticed it never trapped water, water would be coming out of the tool if you were really using it. forget trying to media blast anything. i had a 3/8 50 air hose that i hated, it would always kink, i put the compressor in my garage attic ran the 50' hose to a 1/2" pipe dropdown with a ball valve, a T and a moisture trap ****** below the T, put the filter on that.i am able to shoot primer, paint, media blast for a while. that 50' hose made the world of difference. i broke my filter and the only thing i could find on the spot was one of the tiny ones from sears. that thing traps so much water i have to stay on top of it draining it. i have one of the big blue HF filters im going to chage it out with. i dont think im going to use regulator that came with it though. one thing, the hose is a bit of a restriction, it still works and ive had it this way for about 4 years. today i did price up some black pipe today to make a zigzag run and i might go that route. looks like about 100 bucks will give you a little more than a 50' run.

 

[1931S/X]

for some reason with that setup, when i open the drain on the tank, i dont get any water.

 

[pipsters]

How exactly does the "cooler dry" air go out the top while the hot air stays at the bottom? Have you ever seen how those huge people carrying balloons use hot air to rise?

The way you cool air down is to expand it. Read what he wrote. Also do some calculations, 25 cfm of air going thru a 1/2" pipe will take 0.17 secs. Going thru a 3/8" ID pipe will take 0.09 secs. Less than 1/10 of a second. I would like to know how much cooling you really think will take place in 0.09 to 0.17 seconds. I mean really, it's not going to happen. You have to laugh at all these zig zag wall tubes, such a waste and they do nothing.

The way industry cools air is by expanding it, cooling it, then taking out the moisture, then recompressing it. That is what you are doing by expanding it with a large open pipe with an attached drier before compressing it (shrinking the pipe) again.

Pull the blowoff valve on your compressor, right next to the tank. You will get water blowing right off that. Oh and what does it feel like? Is it cool? Yep, even if the tank has just been filled.

 

[CARS]

Also do some calculations

Why wouldn't it work?? A long run of 3/4" pipe and some "walls" for the water vapor to hit. I agree that a zig-zag wall of pipe will hurt air flow, but so does adding water separators. The longer the run, the cooler the air. A 50' hose is nothing like a 50' run of pipe (copper or iron). It will cool the air.

 

[pipsters]

Why wouldn't it work?? A long run of 3/4" pipe and some "walls" for the water vapor to hit. I agree that a zig-zag wall of pipe will hurt air flow, but so does adding water separators. The longer the run, the cooler the air. A 50' hose is nothing like a 50' run of pipe (copper or iron). It will cool the air.

The air is already cooled as it comes out of the compressor tank. You still don't get it. It's OK, you can't run from physics.

 

[CARS]

The air is already cooled as it comes out of the compressor tank. You still don't get it. It's OK, you can't run from physics.

Physics... ya, I don't remember ever taking that class, but I know for a fact that before I piped my air system in the shop, I just ran a hose off the compressor and it poured water out of my air tools. Rubber is an insulator, pipe is a radiator. 60' of iron pipe before my dryer fixed all of my moisture problems.

I have no idea what sort of compressor you have, but by the time I am done with a paint job, the tank and the air coming out of it is awfully hot.

 

[Falcon67]

The air is already cooled as it comes out of the compressor tank. You still don't get it. It's OK, you can't run from physics.

That must be the idea behind that (can't remember the name) hack job water separator that I found on the 'net. I plan to build one for the new shop. Basically, it's a 1/2 pipe feed that elbows into about the middle of a 2 1/2" x 5' pipe. Or 3" pipe, whatever is handy. The in feed runs from the compressor connection down to near the bottom of the 2 1/2" pipe where it's released into the big pipe. Pressure and velocity drops, condensing out the water. At the top of the 2 1/2" run there is a cap with a feed to the rest of the air system and at the bottom is a ball valve drain. Users claim simple to build and very effective.

 

[scott37300]

That must be the idea behind that (can't remember the name) hack job water separator that I found on the 'net. I plan to build one for the new shop. Basically, it's a 1/2 pipe feed that elbows into about the middle of a 2 1/2" x 5' pipe. Or 3" pipe, whatever is handy. The in feed runs from the compressor connection down to near the bottom of the 2 1/2" pipe where it's released into the big pipe. Pressure and velocity drops, condensing out the water. At the top of the 2 1/2" run there is a cap with a feed to the rest of the air system and at the bottom is a ball valve drain. Users claim simple to build and very effective.

I bought one of these for 32 bucks after 20% coupon, http://www.harborfreight.com/desiccant-air-dryer-97686.html. I have a 30 gallon 2 stage 175 PSI compressor and there is no water after the filter. I didn't get around to piping in my air lines so just have a hose going from compressor to the desiccant filter and then another hose on a reel. The housing on the filter is around 2" and almost three feet long filled with the desiccant pellets. Cheap and effective. This summer I am going to do the pipe work and get a couple more of the desiccant filter from HF. The filters are just a pipe with a cap on each end, the valve is cheap and will probably replace that sometime but other than that there isn't much to screw up so they are a good deal at 32 bucks.

 

[nonhog]

I bought one of these http://www.harborfreight.com/desiccant-air-dryer-97686.html. good deal at 32 bucks.

Has decent reviews, my thought would be there is really nothing there that a guy could not make in a few hours?
So the desiccant is trapped by a screen?

 

[PCO6]

Has decent reviews, my thought would be there is really nothing there that a guy could not make in a few hours?...

I have one too and it works well. You're right, I'll make the next one.

 

[mx842]

Anybody ever tried a toilet paper filter? I have one on my sand blast and paint gun line and it does a really good job. Before I put it on my air line I couldn't sand blast 5 minutes before it would gum up now I can sand blast all day and never have a problem. See here....http://www.tooltopia.com/motorguard-m45.aspx

When I moved my shop not too long ago I also added a copper line cooler like the one someone posted back at the beginning of this thread and I'm sure it helps a lot too, well hopefully it will be better on the compressor tank all that water that collects in there can't be good for the tank. I also added a pop off valve that operates every time the compressor starts or stops on the bottom of the air tank and that purges any water that still finds it's way into the tank as the compressor does it's work.

 

[CARS]

Anybody ever tried a toilet paper filter?

Yes, I have one from TP Tools (part of a set with the filter, separator, and regulator.)

I don't care for the aluminum housing. All the powder coat flaked off the inside and now the aluminum is corroding. I am plagued with chalky white residue every time I change the filter out.

Next time I am opening up the air line system I will replace it. Since it's been a year since I noticed the problem and haven't needed to change anything, I may as well just start taking the pipe apart

 

[scott37300]

Has decent reviews, my thought would be there is really nothing there that a guy could not make in a few hours?
So the desiccant is trapped by a screen?

Yes there is a screen with some stand-off legs on each end to keep the media from blowing out.

It is something that could be made fairly simple but for 32 bucks I didn't think it was worth the time. I'd figure over 20 bucks in material alone with the pipe, caps, valve, welding bungs on for the inlet/outlet, making the screens, buying desiccant median so in my opinion the 32 bucks was easier than making it.

 

[nonhog]

Yes, I have one from TP Tools (part of a set with the filter, separator, and regulator.)

I don't care for the aluminum housing. All the powder coat flaked off the inside and now the aluminum is corroding. I am plagued with chalky white residue every time I change the filter out.

Next time I am opening up the air line system I will replace it. Since it's been a year since I noticed the problem and haven't needed to change anything, I may as well just start taking the pipe apart

Is that a "motorguard"? brand or ?

Yes there is a screen with some stand-off legs on each end to keep the media from blowing out.

It is something that could be made fairly simple but for 32 bucks I didn't think it was worth the time. I'd figure over 20 bucks in material alone with the pipe, caps, valve, welding bungs on for the inlet/outlet, making the screens, buying desiccant median so in my opinion the 32 bucks was easier than making it.

Part of whats so cool about this thread is the do it yourself aspect.
I agree for the price its worth it. I'm down to a couple hundred projects so one more can't hurt.

 

[CARS]

Is that a "motorguard"? brand or ?

There is no identification on it other than what part number for filters to use, and yes. The replacement filters I received were motorgaurd filters.

 

[scott37300]

Part of whats so cool about this thread is the do it yourself aspect.
I agree for the price its worth it. I'm down to a couple hundred projects so one more can't hurt.

I agree with you and I always try to diy when I can. In this instance I just didn't think the 5 dollars or so you will save was worth the time to me, plus I didn't have any of the parts laying around or anyway to thread 2" pipe, not sure if HD or somewhere sells 3' sections of 2" pipe threaded already or not. If you have the pipe laying around then it might be worth it to diy but I'm like you with 100's of other projects I have going on or would rather spend my time on over this filter so I just bought it.

If you do make one please post some pics, and if you need any details of the HF one let me know.

 

[JohnJL]

Ya know, I just realized the AC condenser is designed for exactly this purpose...anyone repurpose a scavenged tube and fin setup from a car for this? I have two large condensors I pulled from the race cars when prepping them and they are just gathering dust. I wonder if I could adapt some fittings or de- and re-braze some fittings to one of them to cool the pressured air.

 

[THEFIX]

Yes there is a screen with some stand-off legs on each end to keep the media from blowing out.

Here is maybe a dumb question, I'm assuming you would want a filter on the secondary side of the media correct? I'm guessing potential media dust in my impact wrench would probably do a lot more damage than moisture would. I have not worked with the desiccant products before but I'm thinking they would have dust associated with them...or no?

 

[scott37300]

Ya know, I just realized the AC condenser is designed for exactly this purpose...anyone repurpose a scavenged tube and fin setup from a car for this? I have two large condensors I pulled from the race cars when prepping them and they are just gathering dust. I wonder if I could adapt some fittings or de- and re-braze some fittings to one of them to cool the pressured air.

What pressure rating do AC condensors have? I thought about using an intercooler I had from my diesel truck but they aren't rated for that high of PSI.

 

[akdiesel]

Physics... ya, I don't remember ever taking that class, but I know for a fact that before I piped my air system in the shop, I just ran a hose off the compressor and it poured water out of my air tools. Rubber is an insulator, pipe is a radiator. 60' of iron pipe before my dryer fixed all of my moisture problems.

I have no idea what sort of compressor you have, but by the time I am done with a paint job, the tank and the air coming out of it is awfully hot.

After the d/p lessons from the compressor to the tank (during pressure build up), the j/t effect is less also. The air temps in the tank will increase. For long periods of air use the metal the tank is made of will absorb the heat and start to heat the air as well.
The idea behind the k/o drums is to create another j/t to help lower the temps, thus droping out liquids.
Heat does rise as we know but the air is cooled due to the j/t when entering the tanks because of the pressure drop.
I have not had a drop of water in my system with my set up. I have an inadiquit (spelling) compressor compared to most so it does run more often.
For addtional removal I will add a small water trap after the k/o drum.
There are alot of good ideas to cool the air down get the liquids to drop out, but some of those don't have the means of removing the liquids once it is cooled off.

 

[zoomzoomjeff]

Can you explain what d/p, j/t effect, and k/o drums mean to
<----------this guy?



And does anyone have a link to this DIY device you're describing?

 

[akdiesel]

Sorry I work in this area so I figured it was known.

d/p= differential pressure. The pressure upstream and down stream of an oriface or simply a tight location in a line or vessel.
j/t= jewels thompson. A term used when a d/p is applied and temps drop on the downstream side. Just like when you blow on somthing to cool it down versus when you try to heat your hands. Your mouth act just the same way to how much open your mouth is creating a greater d/p. I know it is an odd annolgy.
k/o= knock out drum. A vessel, drum, or tank used to knock out liquids due to cooling. Usually entering in the side. Gas will then leave out the top and the liquids are then removed out the bottom via a bleed valve.
I hope I explained well enough.

Here is a link to when I just installed it. I has since been completed and the lines are all run.

http://www.garagejournal.com/forum/showthread.php?t=31555

 

[zoomzoomjeff]

Okay. Thanks, Ak!

 

[W-Cummins]

Here is maybe a dumb question, I'm assuming you would want a filter on the secondary side of the media correct? I'm guessing potential media dust in my impact wrench would probably do a lot more damage than moisture would. I have not worked with the desiccant products before but I'm thinking they would have dust associated with them...or no?

Not a dumb question at all. And yes you normally do want to run an after filter to remove any desiccant that passes over, from the air. Here is a picture of my new to me drier, and as you can see there are pre and post filters on the unit with differential pressure gage's

William....

 

[zoomzoomjeff]

William---WOW!! Do you run a business with that equipment or just for weekend warrior stuff? Either way, I like it.

Whereabouts in IA are you?

 

[W-Cummins]

William---WOW!! Do you run a business with that equipment or just for weekend warrior stuff? Either way, I like it.

Whereabouts in IA are you?

It's just for my own play pen/fun center at this point. Just about 110 klicks east of you.


here is a picture of the filter bank that is all most setup now

That setup should produce breathing quality air. I may remove the filter from the last unit as I really don't need that fine of filtration, but I may just see how long it takes to plug it up too. The filters should last a long time as I'm not putting much air through them compared to their rated 800-900cfm capacities.

William...

 

[ARAMP1]

It's just for my own play pen/fun center at this point. Just about 110 klicks east of you.


here is a picture of the filter bank that is all most setup now

That setup should produce breathing quality air. I may remove the filter from the last unit as I really don't need that fine of filtration, but I may just see how long it takes to plug it up too. The filters should last a long time as I'm not putting much air through them compared to their rated 800-900cfm capacities.

William...

Please explain what each one is/does. I'm in the process of setting mine up now and need some direction.

 

[W-Cummins]

Well from right to left they are
F35 5 micron pre-filter
M32 B1.0
M32 C.01
M32 D.003

“M” Series Coalescing Filters, with Type “B1” 1.0 micron elements:
All Wilkerson Type “M” Oil Removal (Coalescing) Filters with Type “B1”
1.0 micron elements exceed ISO Class 2 for maximum particle size and
concentration of solid contaminants, and exceed Class 3 on maximum
oil content (mg/m3 ).

“M” Series Coalescing Filters, with Type “C” 0.01 micron elements:
All Wilkerson Type “M” Oil Removal (Coalescing) Filters with Type “C”
0.01 micron elements exceed ISO Class 1 for maximum particle size and
concentration of solid contaminants, and exceed Class 1 on maximum
oil content (mg/m3 ).

“M” Series Adsorption Filters, with Type “D” 0.003 micron activated
carbon elements: All Wilkerson Type “M” adsorption filters with Type “D”
0.003 micron activated carbon elements exceed ISO Class 1 on maximum
oil content (mg/m3 ).

BTW I was wrong the max flow is 741cfm for the M32 filters, not 800cfm as I posted above
the F35 flows 970cfm ( this is for the 1 1/4" models I'm using)

William....

 

[vonhef]

Well from right to left they are
F35 5 micron pre-filter
M32 B1.0
M32 C.01
M32 D.003

“M” Series Coalescing Filters, with Type “B1” 1.0 micron elements:
All Wilkerson Type “M” Oil Removal (Coalescing) Filters with Type “B1”
1.0 micron elements exceed ISO Class 2 for maximum particle size and
concentration of solid contaminants, and exceed Class 3 on maximum
oil content (mg/m3 ).

“M” Series Coalescing Filters, with Type “C” 0.01 micron elements:
All Wilkerson Type “M” Oil Removal (Coalescing) Filters with Type “C”
0.01 micron elements exceed ISO Class 1 for maximum particle size and
concentration of solid contaminants, and exceed Class 1 on maximum
oil content (mg/m3 ).

“M” Series Adsorption Filters, with Type “D” 0.003 micron activated
carbon elements: All Wilkerson Type “M” adsorption filters with Type “D”
0.003 micron activated carbon elements exceed ISO Class 1 on maximum
oil content (mg/m3 ).

BTW I was wrong the max flow is 741cfm for the M32 filters, not 800cfm as I posted above
the F35 flows 970cfm ( this is for the 1 1/4" models I'm using)

William....

Question:

Why not use just the prefilter and the D.003?

 

[Blwnsln]

Sorry to bring up an old thread. But I'm wondering if I able to run a descant filter before an air drier?