Copper air line cooling question

[mcarroll_nz]

I'm about to start running copper air lines for my 5 hp 60 gal compressor around my shop. I've got a mix of 3/4 and 1/2 type L 10 ft pipes from HD and just waiting on the fittings to arrive from supplyhouse.

I'm working on the premise that 50 ft of 3/4 copper will cool the air sufficiently before it hits the separator and filter. I'm putting tee fittings every 10 ft with water drops - 30 ft on a gentle slope down, then loop around and 20 ft back, also on a gentle down slope, all starting out with a flexible hose fitting from the compressor.

My question is: I have read that adding tees and 90 degree elbows has an impact on psi. So I'm running 30 STRAIGHT feet with tees every 10 ft for water drops and the same for the 20 ft back to minimize the drop in psi. However, my compressor has plenty of psi to play with, so if I lose a few pounds then it's no problem. I've also read that when moisture laden air hits a barrier like a 90 degree bend then it's more efficient at dumping the moisture. So should I have the equivalent of 90 degree elbows going up a few inches every 10 ft (with water drops, thus being a tee) so the humid air has barriers to hit - or is a straight shot just as effective?

Thanks in advance.

 

[Warrenator]

I think in practice, you will find that it doesn't matter. If it were me I would simplify the layout as much as possible and maybe only have a drip leg at the beginning and end of your long run. Any moisture that didn't fall out in those drip legs will be caught in the moisture separator.

 

[mcarroll_nz]

Thanks for the advice - food for thought.

Cheers.

 

[sberry]

With 3/4 and a system this short there will not be any pressure loss. Absolutely not to worry about it at all. The losses will be thru the final hose, 2# down the main and 25 down a 3/8 hose with a heavy 1/2 air gun.

 

[engineer2]

Doesn't matter. Ball-park figures: If your humidity at the compressor inlet is above about 35% RH, your compressed air will be close to 100% RH by the time it is cooled down to room temperature. You may not notice any condensation when air is discharged, as it will be a fog that evaporates quickly. Not a problem for home shop use, unless you are spray painting in which case a desiccant cartridge is a good idea. The best solution is a refrigerated air dryer, but they are spendy for a problem most people don't notice.

 

[raferguson]

Living in a humid environment, you will get more water out of the air than I do in Colorado. 50 feet of black iron is usually considered adequate, so 50 feet of copper should be more than adequate. As others have mentioned, you would need a special filter for spray painting. Actually, a filter is a good idea regardless. Refrigerated air is overkill for most folks.

I would not worry about pressure drop in 3/4 or 1/2 inch pipe, it is likely to be less than 5 psi, but you can look it up. Worst case for my tools is about 15 scfm, higher than for most folks, but I run grinders continuously.

Keep it simple, but slope the lines at least 1 inch per 10 feet, and have a drip leg with a valve at any low spots.

 

[gerryw]

Sounds like a good plan.
As mentioned, practice and theory are two different things.
I have same compressor specs, run 1/2” copper (probably 50’ total)
a ton of 90’s and all sorts of “wrongs” and works amazing (over 20 yrs)
Enjoy

Gerry

 

[mcarroll_nz]

Thanks all, much appreciated. I'll keep it simple with 50 ft of straight 3/4 and two water drops at the low points.

 

[boosted-delslow]

In my opinion if it is general purpose air for running things like air tools and filling tires it is not worth all the thought, time and money to worry about a ton of dryers and drip legs. I know some guys on here have built some very elaborate air setups and they look great but do you really need them? If you are painting cars or supply air to sensitive instrumentation yeah. But for your shop I would keep it simple. This is my opinion of course.

 

[gtr1999]

Maybe someone can clarify how series of vertical lines would dry the air? I have seen some online that might be 4-5' long, with 4-6" in between and several parallel runs with drains on each low leg? I will be setting up my new compressor soon and haven't looked into this too much yet.

I might have access to a ZEKS 50hp drier in good shape but is it worth the power to run it?

 

[engineer2]

Maybe someone can clarify how series of vertical lines would dry the air?

It won't. An aftercooler will cool the air and moisture will drop out as the temperature drops. You can cool the air to room temperature, but it will still be saturated with moisture if the RH of the air going into your compressor is above approx 35%.

I might have access to a ZEKS 50hp drier in good shape but is it worth the power to run it?

I assume you mean 50 scfm. I would run it 20 minutes before you need it and only during humid weather or if you are painting or sandblasting.

 

[gtr1999]

The Zeks I can get is a HSF 200 that we used in our shop system with a 50hp compressor. So it is 200 scfm but won't do me any good since it is wired 460 3 phase and I don't think I want to add a phase convertor for that with my usage. I will be using a blast cabinet and tools, not sure about future painting but probably not.

 

[gtr1999]

Yes that is my concern. I don't want to hijack this thread from the OP question so once I get back to this I will start a fresh thread on the subject.

Thanks guys.

 

[sharpjes1]

Keep it simple.
Remove the oil with a coalescing filter.
Remove particulates with (at least) a 5 mcron filter
Dry the air with a dessicant dryer.
You'll have clean and dry air with a system that follow these guidelines.

 

[engineer2]

Zeks I can get is a HSF 200 ...200 scfm ... wired 460 3 phase an

Vastly oversized. Even though it will have a hot gas bypass system for lighter loads, it just ain't worth it.

Keep an eye open for used air dryers on CL. They come up now ant then. Most people don't know what they are, so they often linger.

 

[tcianci]

In a lot of cases, doing it elaborately equates to doing it right. Given different climates and usages, the only "ONE SIZE FITS ALL" air system is one that is overkill in 99% of the installations. Most guys would do well to concentrate on getting their air to the required locations as simply as possible and then see what type of circumstances they encounter.

I'm in Massachusetts and we get some severe humidity in the summer (fortunately not for months on end) I run an 80 gallon 17 CFM compressor and use air tools, a TP blast cabinet and automotive spray guns. There are 2 hose reels, one at each end of the garage fed by 1/2 inch copper and a couple of drain valves. Never experienced media clumping or water in the paint jobs and the only post compressor accommodations are a disposable desicant filter at the gun.

 

[csp]

It doesn't really have as much to do with the outside humidity.

Sure it does! Drier air going into the compressor has less water in it to begin with.

 

[sberry]

Mine is simple, no extra equipment other than a filter, I paint, I blast.

 

[steel 35]

Portland, Oregon, gets 44 inches of rain per year.

Maybe someone can clarify how series of vertical lines would dry the air?

The vertical lines, collect the moisture.
The first thirty feet cool the air in copper line enough to start separating condensation, a change in direction causes the moisture to hit something there for it is slowed down and if the flow is not fast enough to push the separated water up it goes down into the Collecting vertical line.

Think water separators same thing!

 

[Lelandwelds]

Portland, Oregon, gets 44 inches of rain per year.




The vertical lines, collect the moisture.
The first thirty feet cool the air in copper line enough to start separating condensation, a change in direction causes the moisture to hit something there for it is slowed down and if the flow is not fast enough to push the separated water up it goes down into the Collecting vertical line.

Think water separators same thing!

I'm about to start running copper air lines for my 5 hp 60 gal compressor around my shop. I've got a mix of 3/4 and 1/2 type L 10 ft pipes from HD and just waiting on the fittings to arrive from supplyhouse.

I'm working on the premise that 50 ft of 3/4 copper will cool the air sufficiently before it hits the separator and filter. I'm putting tee fittings every 10 ft with water drops - 30 ft on a gentle slope down, then loop around and 20 ft back, also on a gentle down slope, all starting out with a flexible hose fitting from the compressor.

My question is: I have read that adding tees and 90 degree elbows has an impact on psi. So I'm running 30 STRAIGHT feet with tees every 10 ft for water drops and the same for the 20 ft back to minimize the drop in psi. However, my compressor has plenty of psi to play with, so if I lose a few pounds then it's no problem. I've also read that when moisture laden air hits a barrier like a 90 degree bend then it's more efficient at dumping the moisture. So should I have the equivalent of 90 degree elbows going up a few inches every 10 ft (with water drops, thus being a tee) so the humid air has barriers to hit - or is a straight shot just as effective?

Thanks in advance.

Wow. Some slight misconceptions are out there.

I used to dump far more heat in 12" than you will in 30 feet with liquids harder to condense than plain old WATER. I used static jackets of water, dry ice, or LN. A simple radiator can approach 10°F above ambient in a space almost as compact without the liquid or phase change. However you get there, that is the best that can be done. Removing more water requires raising the pressure, dropping the temperature, or adsorbing the water on some media. Gravity or a properly sized coalescing filter will help collect the already separated out liquid water. If the water is in vapor form, it will zip through without being collected.

Bends and fittings drop pressure in a DYNAMIC system. A STATIC state will reach equilibrium at whatever your max pressure is. The pressure drop is too minor to be noticed in any system under any reasonable standard. ( so, run 3/4" and forget about it.) If extra volume from larger piping is easier than a larger tank, then go for it. If you build a weirdly complicated and restrictive system than I can picture, a second dry tank near your largest air hog will minimize any reasonable air starvation.

 

[Lelandwelds]

Maybe someone can clarify how series of vertical lines would dry the air? I have seen some online that might be 4-5' long, with 4-6" in between and several parallel runs with drains on each low leg? I will be setting up my new compressor soon and haven't looked into this too much yet.

I might have access to a ZEKS 50hp drier in good shape but is it worth the power to run it?

1. Dump the heat as simply as you can.
2. Separate the resulting liquid water by gravity, centrifical,etc.
3. Remove particulates to a reasonable level.
4. Remove all oil possible.
5. Eliminate leaks regularly.
6. Think of ways to reduce electricity use (reduce leaks. Lower excessive supply pressure. Lower excessive pressure at tools.)

Tools and processes of interest here do not appreciate liquid water. Water vapor is not a problem as long as it stays in gaseous form.

 

[JohnnyK81]

I'm about to start running copper air lines for my 5 hp 60 gal compressor around my shop. I've got a mix of 3/4 and 1/2 type L 10 ft pipes from HD and just waiting on the fittings to arrive from supplyhouse.

3/4" copper line in a home garage for a 60 gallon compressor sounds like someone who did their compressor plumbing research on internet forums!

That is extremely overkill, and you will see zero sort of any drop. You would see zero drop with 1/2" as well. As someone else stated, if you were to notice anything (You won't), it will be through the air hose fittings that are 1/4" npt.

 

[Lelandwelds]

3/4" copper line in a home garage for a 60 gallon compressor sounds like someone who did their compressor plumbing research on internet forums!

With scrap and surplus available, often overkill may be far cheaper than new and does no harm. Even with new material, the difference in cost between 1/2" and 3/4" is minor for BP, copper, and PEX. Extra capacity with minimal extra cost doesn't warrant much ridicule.

I knew a guy who checked for gas leaks with a bic lighter. He used to make fun of kids who "had some book learnin on them." He burned his trailer down.

 

[JohnnyK81]

With scrap and surplus available, often overkill may be far cheaper than new and does no harm. Even with new material, the difference in cost between 1/2" and 3/4" is minor for BP, copper, and PEX. Extra capacity with minimal extra cost doesn't warrant much ridicule.

I knew a guy who checked for gas leaks with a bic lighter. He used to make fun of kids who "had some book learnin on them." He burned his trailer down.

Wait, wouldn't we be the ones with book learning in this scenario?

But anyway, not ridiculing at all.! If it's cheaper especially, go for it. I'm just saying completely unnecessary. If you read up on hotrodders, or some other forums, you quickly come to understand there isn't an engineering degree to be found on any of the 'compressor experts' on that forum (for example).

 

[Markfothebeast]

I have about 25' of 3/4" copper after the tank, which has had very little impact in aiding in moisture separation. I did have 20' of copper tubing between the pump head and tank and this was hardly cooling the air (not even a drop of water in the separator before the tank). This copper tubing would exceed 220F during an 8 minute cycle while the pump head output would read up to 315F - 325F.

I'd found a central AC evaparator coil in the neighbors scrap pile which became an experimental cooler between the compressors pump head and tank. I had to do some cutting and copper sweating to set it up. The pump head output is right around 280f - 290f now towards the end of a tank fill cycle.

The input plumbing of the cooler is roughly around 200F. The output of the cooler at the copper fittings to the separator are about 80F - 90F. However, I had to use what I had at the time for fittings and put a couple black steel reducers in there - these become much hotter. The first obvious difference after installing the cooler before the tank is when I now drain the tank, the drain pipe becomes ICE cold - and the separators are now catching a lot of fluid.

After a 20 minute long cycle I will get a bit of moisture here and there. To help with this, I have two fans intended for use in the cooler but due to the winter, I have not finished this project. I do need a drain valve in the piping out of the tank as well. The pump output line is a hydraulic hose rated for 200F. I guess I'll be finding out how long it holds up.

Here's a quick look at how it's currently set up till the weather warms.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[Markfothebeast]

I ranted off from the subject a bit. My answer to the original post would be to have less concern about cooling after the tank. All of this should be taken care of before the tank. Than there is less worry about buying 3/4" drain valves and run the piping directly to the desired destination. And you'll also increase the life of your tank.

-Markfothebeast-
(www.youtube.com/markfothebeast)

 

[mcarroll_nz]

Well, for better or worse, this is where I'm at (see attached pic). About 50 ft of 3/4, then going into this guy (http://www.pneumaticplus.com/pneumaticplus-sau-series-three-stage-air-drying-system-1-2-npt/) then 1/2 inch after that.

All joints pressure and leak tested 100% so not so bad for a first-timer.

Keeping it simple for the time being with an outlet near the ceiling for a mounted hose reel and one more outlet; mostly for my blast cabinet and later, powder coating. Planning to extend the lines as I figure out my shop usage. If I get grief from moisture then I'll be installing a Hayden 1260 aftercooler.

Thanks for all the input and comments.

 

[bad_idea]

Do you have plans for the wall space above the air piping? If not, I would suggest you move your piping up close to the ceiling. I would be concerned about your piping getting banged up at that height. I'm a bit rough in my shop space though.

 

[Lelandwelds]

I have about 25' of 3/4" copper after the tank, which has had very little impact in aiding in moisture separation. I did have 20' of copper tubing between the pump head and tank and this was hardly cooling the air (not even a drop of water in the separator before the tank). This copper tubing would exceed 220F during an 8 minute cycle while the pump head output would read up to 315F - 325F.

I'd found a central AC evaparator coil in the neighbors scrap pile which became an experimental cooler between the compressors pump head and tank. I had to do some cutting and copper sweating to set it up. The pump head output is right around 280f - 290f now towards the end of a tank fill cycle.

The input plumbing of the cooler is roughly around 200F. The output of the cooler at the copper fittings to the separator are about 80F - 90F. However, I had to use what I had at the time for fittings and put a couple black steel reducers in there - these become much hotter. The first obvious difference after installing the cooler before the tank is when I now drain the tank, the drain pipe becomes ICE cold - and the separators are now catching a lot of fluid.

After a 20 minute long cycle I will get a bit of moisture here and there. To help with this, I have two fans intended for use in the cooler but due to the winter, I have not finished this project. I do need a drain valve in the piping out of the tank as well. The pump output line is a hydraulic hose rated for 200F. I guess I'll be finding out how long it holds up.

Here's a quick look at how it's currently set up till the weather warms.

-Markfothebeast-
(www.youtube.com/markfothebeast)

Well, that was different. Usually most people use a condenser. (It is made to dump heat and take pressure.) An 18" water jacket vented to atmosphere works. It is pretty easy to approach 10° F over ambient before the tank.

 

[2Big2Ride]

Well, for better or worse, this is where I'm at (see attached pic). About 50 ft of 3/4, then going into this guy (http://www.pneumaticplus.com/pneumaticplus-sau-series-three-stage-air-drying-system-1-2-npt/) then 1/2 inch after that.

All joints pressure and leak tested 100% so not so bad for a first-timer.

Keeping it simple for the time being with an outlet near the ceiling for a mounted hose reel and one more outlet; mostly for my blast cabinet and later, powder coating. Planning to extend the lines as I figure out my shop usage. If I get grief from moisture then I'll be installing a Hayden 1260 aftercooler.

Thanks for all the input and comments.

The motorcycles! (In the pic)

 

[Bretny]

I added a cooler between the pump and tank. I get almost 75 percent of my water out of the system there.
It uses a 3/8x20ft copper coil then into 4 3/4 Ts. Adding volume to your cooler will slow the air and allow it to properly cool. Cool air cant hold as much humidity. I have used this system for about 9 years. I paint, sand blast and use a plasma cutter with no extra water traps.

 

[Lelandwelds]

I added a cooler between the pump and tank. I get almost 75 percent of my water out of the system there.
It uses a 3/8x20ft copper coil then into 4 3/4 Ts. Adding volume to your cooler will slow the air and allow it to properly cool. Cool air cant hold as much humidity. I have used this system for about 9 years. I paint, sand blast and use a plasma cutter with no extra water traps.

This sounds like my experience. Do you own a laser temp gun? I bet you are 25°F over ambient temperature.

 

[Bretny]

I do own a temp gun but never checked it. I have a piece of cheap pvc air hose coming out of this cooler to the tank and it never melted. Same hose for 9yrs and its not even rubber.

 

[Milton Shaw]

One thing I can advise is that you make sure you remove the burs on the pipe ends after you cut the pipe. It effects the pressure under flow. Not the pressure in static conditions. The burs will also trap a drop or two of water and then release it when you increase flow rate. A smooth pipe will let the water flow to the traps for removal..

 

[mcarroll_nz]

I added a cooler between the pump and tank. I get almost 75 percent of my water out of the system there.
It uses a 3/8x20ft copper coil then into 4 3/4 Ts. Adding volume to your cooler will slow the air and allow it to properly cool. Cool air cant hold as much humidity. I have used this system for about 9 years. I paint, sand blast and use a plasma cutter with no extra water traps.

Interesting, so you don't use a proprietary oil cooler? Just the copper coil into a series of tees with no other cooling method? It sounds pretty effective. Do you have a pic or diagram? Thanks.

 

[mcarroll_nz]

The motorcycles! (In the pic)

Plenty of bike projects waiting to happen, just getting my shop finished first. Almost there so pretty soon I'll be out of excuses...

 

[Lelandwelds]

I do own a temp gun but never checked it. I have a piece of cheap pvc air hose coming out of this cooler to the tank and it never melted. Same hose for 9yrs and its not even rubber.

Just curious but if you are dropping a noticeable amount of water before the tank, you have nailed it

What brand of super duper hose lasts 9 years? Please share.

One thing I can advise is that you make sure you remove the burs on the pipe ends after you cut the pipe. It effects the pressure under flow. Not the pressure in static conditions. The burs will also trap a drop or two of water and then release it when you increase flow rate. A smooth pipe will let the water flow to the traps for removal..

You are being too subtle. Many people won't get the joke.

Interesting, so you don't use a proprietary oil cooler? Just the copper coil into a series of tees with no other cooling method? It sounds pretty effective. Do you have a pic or diagram? Thanks.

Lots of ways to get there. Coiled copper. Finned copper. Flattened copper. Stacked plate. Transmission coolers. A/C condensers. Water jacket. Auxiliary air tank. Just cool it, separate it, and drain it. How, where, or when doesn't matter much.

I wish more people put this kind of effort into fixing those expensive air leaks. This is like the old arguments over 327 vs. 350, coke vs pepsi, .30-06 vs .270, or charcoal vs propane.

 

[steel 35]

Wow. Some slight misconceptions are out there.

I used to dump far more heat in 12" than you will in 30 feet with liquids harder to condense than plain old WATER.

Think I will go out and shorten mine to less then 12" and plug all the ball valves just because you said so.

 

[Lelandwelds]

Think I will go out and shorten mine to less then 12" and plug all the ball valves just because you said so.

About a hundred years ago, I thought I wanted to be a chemistry major. I did lots of glasswork and distillation. I used co2 snow, LNI, and plain old water jackets . I did lots of other people's gruntwork, too. None were longer than 12".

I would stay with air to air exchangers. One or two square feet should finish about 10°F over ambient temperature. Easy peasy. Go look at an AC condenser. Same exact idea. No need to invent a Franzinator.

Why would you plug your balls? Once you make liquid water you need to dump it.