Plumbing Air Lines (Q's)

[OH-MAN]

This is great I used PVC when I set up my garage. My compressor is in the shed on the side of the garage, the PVC runs under the concrete floor, where it subs up about 2.5' I transistion to galvanized pipe. Should I rerun, which would **** as it would have to be surface or would I be OK with cutting the PVC at the floor and installing a coupling to transition to galvanized? I could even put a metal sleeve over the coupling for protection.

What do you guys recommend?

The underground will not kill you if it blows. Cut it about 3" above the floor then cut a sch 80 PVC ****** in the middle so you have a slip by male thread ******, Glue the slip end with a coupling to the pipe stubbed out of the floor. Thread your steel or copper adpt onto the sch. 80 ****** thread. Do this on both places where it comes out of the ground. If it blows under the ground you will just have to replace it anyway. The colder underground temps will drop water out of the compressed air so make sure you have some good quality filters above where it comes in to the garage.
Good luck

 

[js73751]

OI812 hit it dead on. Moisture is the biggest problem in air systems. The entire run should start up high and run downwards towards the last hookup with a water drain at bottom of each drop. If you ever plan on doing any painting, you will always have a moisture problem. If you are just running air tools just make sure you keep them well oiled. With your tank outside please make sure you drain the tank of moisture at the end of the day when in use. Check the diagram below for the basic concept.

www.sharpe1.com/dr-pipe.htm
Joe

 

[Double Venom]

You guys have proven you can teach old dogs new tricks! PVC...if you use it, please have someone around after the fact to take pictures, we want to see them. Now that we have beat PVC into th ground, lets move on. One more note though on PVC, in my old shop I was going to use PVC! I had estimates for over 1,000 feet of the stuff and all the fittings, ball valves to 'drops'. Whn a plumber/friend asked me what I was doing with that much PVC? Immediately after I told him what I had in mind I had to admisinister CPR to the guy! Well not quite but almost. He then showed me some very ugly pictures of what could happen.

So, at this point, and not wanting to do it again, or get someone hurt we used 3/4 black pipe through-out the entire shop including the booth. After ten years of this system without a problem we started getting very small black dots in our "HOK", (all) paint jobs! We tried everything to find out what the heck was gong on right to the point of calling the Dupont Rep. in and giving him a ton of grief about what was going on! Turned out, (as one of the guys mentioned) our black pipe was rusted (scaling) inside and the smallest particles where making it through THREE air/water filters making their way into and on our paint work!

I had no idea that copper was a viable solution! Now I know. Even on the link above to the "SHARPE" site they show copper being used. I suppose I should have known, on all large compressors that I know of every 'feed' tube coming off the compressor head into the tank is copper!

DV...I can do copper!

 

[Ken Greene]

hidy ho DV,
KG From DVSF III (the guy that gave you the discs of pictures the last day at the air field)
Yup Copper is the olny way to fly. Where i work we have Alomst a mile of Copper carring air everywhere. No specs, easy to add onto, cheap to buy, and fast to install

 

[OI812]

Sorry DV, I didn't mean to beat it to death. People kept on bringing it up so I thought I would be a little sarcastic. I was just trying to get the point across, I guess maybe I should have said nothing.

 

[Double Venom]

01812,
Sarcastic!? Did you not note sarcasm in my post? I think this is a good thing! Guys that were, aren't, guys that have, are now having second thoughts! I'm a heck of a preacher myself! I don't want anyone to get hurt... I think, for what that's worth, you did good!

KG, Yes I remember, and thank you! I still have that CD somewhere, and I do have all those pictures here on my computer. I hope you feel the 'Flings' were worth your time and effort. A truly valuable and worthy event. I loved every minute of every year.

DV...retired

 

[byrdman]

OK, so now that the PVC discussion is over, who can tell me what I need to join Schedule L copper? I've heard you need to use silver solder, and more of a torch than just a Benzomatic.

I'd also be interested in the GaragePak system that Roadster mentioned, but I'm just guessing it's much more expensive than copper? Their website gives no estimates on cost. Roadster, any comments? Or pictures!?

 

[OI812]

No need for silver solder unless you are going to extremely high PSI. Under 200 psi I believe regular solder would be just fine. I do commercial and industrial piping all week long and some jobs they require silver solder,and some require regular solder. It all comes down to how much money the Engineer wants to put in his pocket.

Silver solder requires temps in the 1500 to 1700 range. Regular solder is in the 500-750 range. Personally for an air line I would use regular solder. Silver soldering takes the temper out of the copper, and the copper becomes soft and bendable. I don't think you really want that. Don't quote me on this, but I believe silver solder is like $70/lb. A silver solder joint is stronger, but for your applications you don't need that much additonal strength. When you silver solder you have to heat the copper until it is cherry red, and let me tell you that is hot. You would need a turbo torch or an oxy-act. torch. Silver soldering is not like regular soldering either, it is a different animal. In the end stay with regular solder.

 

[Ken Greene]

use standard solder but let me recomend MAP gas instead of propane. Its hot, its fast and makes doing 3/4 pipe a brease. unless you have access to and acetalene plumbers torch MAP is the way to go.

 

[byrdman]

No need for silver solder unless you are going to extremely high PSI. Under 200 psi I believe regular solder would be just fine.

Where can I find out for sure if regular solder is enough for 175psi? Also, is schedule "K"(regular water pipe copper) enough for 175psi or do I have to use "L"? I'm planning to run 3/4".

Ken, how does map gas come? I mean, does it come in those small cylinders like for use with the little brass benzomatic torch, or is it something you need an oxy-acet rig for? I've heard of it, but I've never used it.

 

[Ken Greene]

yup MAP comes in small cylinders like propane. Bernzomatic makes a nice kit that comes witht the tank (yellow tank) and an auto lighter/torch head. You can find it at all theh big box lumber yards

 

[OI812]

byrdman

I will start working on your question of the ratings.

For your information Type L is a thinner wall then type K, L should be fine.

MAPP gas is hotter then propane, and is much better then propane. It can be used with benzomatic(sp?) torches. I'm not sure what you mean by little torches.

 

[byrdman]

OI812, I was thinking schedule "K" was regular old water pipe. I guess that must be "M". Got it backwards I guess.
Whatever schedule it is, is regular water pipe copper enough for 175psi compressed air, or do I have to run "L"?

Do you know where I can find out for sure if regular solder is rated for 175 psi?

Thanks to you and Ken also for the map info.

 

[OI812]

I took care of you, I asked the question from the experts--The copper institute. I can tell you this on one of the tables it has a listing of what tubing is good for. Type L was the last one to be listed for compressed air. As soon as I get the e-mail back from them I will post it. Hope this helps.

 

[OH-MAN]

OI812, I was thinking schedule "K" was regular old water pipe. I guess that must be "M". Got it backwards I guess.
Whatever schedule it is, is regular water pipe copper enough for 175psi compressed air, or do I have to run "L"?

Do you know where I can find out for sure if regular solder is rated for 175 psi?

Thanks to you and Ken also for the map info.

L is fine. Any solder will handle the pressure. What are you running that needs 175 psi?

 

[byrdman]

175 is the max psi of the compressor I want. I realize most tools don't require that much pressure, but it seemed to make sense to plan for it.

Looking forward to hearing back from the copper folks, OI812.

 

[OI812]

I e-mailed the Copper Development Association and asked the following questions and got the following answers.

Your question was: I am looking at installing a compressed air system in a garage with Type L copper (3/4") and lead-free solder. The system pressure would be 175 psi. What would be the burst pressure on the copper tube, and is regular lead free solder safe for the system. What would be the maximum safe working pressure for this system?

Response: FOR SOFT TEMPER,BURST PRESSURE IS 2935 PSI AND MAX SAFE W.P. IS 582PSI.FOR DRAWN TEMPER,THESE VALUES ARE 9300 PSI AND 1002 PSI.

Your question was: So for Type L drawn temper, and lead free solder would I be safe at installing this system? The system is compressed air at 175 psi.

Response: this should be satisfactory.

I figured you would be safe, I was sure the copper was rated for the PSI. Wasn't sure on the solder strength, but I was also sure that would be fine. So now you have it from the higher ups. Just make sure you don't use Type M. That is the thin wall copper. Thickness in copper from thinnest to thickest is M, L, K. There are some other grades, but you probably won't run across those. Hope this helps. If you want to know more about copper go to Copper Development Association

I just stopped by Canfield's site. They are a manufacture of lead free solder. Here is some info from there site that might be helpful on lead free solder.

Temperature Range - 440° - 660°
Purity - 99+%
Shear Strength - 10,000 PSI (Room Temperature); 6,000 PSI (at 250°)
Tensile Strength - 8,000 PSI (Room Temperature); 5,000 PSI (at 250°)
Density - 0.265 Pounds Per Cubic Inch

 

[byrdman]

wow! Now that's service. Thanks a million for the legwork there.

I have to say, I kinda wondered who copper.org was to be answering these questions. So, in looking around on their website, I found this under the "Mission" statement:

4. CDA represents the U.S. copper and brass industry as a central authoritative source of technical data and information on the selection, fabrication and use of copper and its alloys.

Guess that ought to do!

This is a relief. Using regular solder sounds a heck of a lot easier. Thanks to all who responded.

 

[sca037]

Great discussion!

Thanks to all the advice here, I've decided to go with 3/4" schedule L copper. Maybe I'll do the drops in 1/2".....or just do it all in 3/4" to simplify the hardware issues, since the co$t difference for my project would be small.
Now, I would really like to utilize the disconnect ports that have a line pressure release (like the Garage-Pak system has)...........where can I find these?

As the originator of this thread, I've gotta say you guys rock
Brian

 

[OH-MAN]

175 is the max psi of the compressor I want. I realize most tools don't require that much pressure, but it seemed to make sense to plan for it.

Looking forward to hearing back from the copper folks, OI812.

After you get everything setup, turn the pressure regulator down to the max pressure you will need. If you only need 80psi do not run the compressor up to 175. This will alow it to make more cfm and recover quicker. Shorter run times make the compressor happier.

 

[TuckinToyz]

My shop is just about to be built and I'm going with copper lines type L. I work in HVAC and mainly mechanical systems in hospitals. We used copper for all the medical gas lines (oxygen, etc), so it's safe enough for your shop. As for pressure, when I install new equipment at peoples homes, I 'leak test' the soft copper line set with Nitrogen at 350psi and it holds pressure, including the joints. I braze the copper with an oxygen/acetylene torch setup and stick solder-it's melting point is 840 degrees and it is strong if done properly. I do however have a buddy (who does the same work I do) with a 40x60 shop and he used 1" pvc running all around his shop and it seems to work fine. It has been in for several years. Dunno

 

[OI812]

I do however have a buddy (who does the same work I do) with a 40x60 shop and he used 1" pvc running all around his shop and it seems to work fine. It has been in for several years. Dunno

The PVC issue is dead, there is no reason to discuss it any further. I have posted pictures up of what CAN happen with PVC and compressed air. Most of all you should know being in the trades. I am also in the trade and only work on industrial, commercial buildings. I also know that just because something is done doesn't make it correct. The manufacture doesn't recommend it, the engineers don't recommend it, so who else do we need to contact to prove the point that it is not a good practice.

It might have been in for 2 years, and it might be fine for the next 20 years. Then again he might slip with a hammer in the cold, hit the line and it explodes send little pieces into his body. If he has PVC buried in his body, I bet he won't think the PVC was the way to go then.

I will say it one last time if you want to use PVC go ahead, it's your life.

 

[TuckinToyz]

My shop is just about to be built and I'm going with copper lines type L.

If you read my post, you see what my choice is. All I did was say I know someone who has done it-you don't have to act like a .... moderator.

 

[Luckydevil]

Please don't take it personal, he's just looking out for you and your friend with the pvc. A lot of people use pvc for airlines without knowing the risk associated. The last thing any of us want to hear is that someone got hurt by it. Good job doing it the right way and going with copper in your shop.

 

[Double Venom]

Luke,
Well explained!
DV...

 

[OI812]

If you read my post, you see what my choice is. All I did was say I know someone who has done it-you don't have to act like a .... moderator.

I apologize for sounding kind of harsh. As Luke said I don't want anyone getting hurt. That is my main goal. I did notice you used the proper material and I applauded you for that.

I actually do have a couple of questions for you. You said you are using and oxy-act. torch. Are you using a rose bud to solder with that? You said the solder you are using melts at 840. Most silver solders melt in excessive of 1000 degrees. Are you using stay silver or bridget solder? I know those solders have a higher melting point, not sure where they are at. Is there a reason you are using those solders? I know those type of solder are about 4 times the cost of regular solder.

 

[liquidneon]

What about buried lines? Im planning on putting my compressor in the yard tool shed about 100ft away from the garage and running a line underground. Being in michigan Ill have to deal with ground freeze issues. Any recommended depth to bury the line? L or K copper for the line be ok? What about temp change issues???

 

[GearHead_1]

Having worked in a shop that had buried lines I have an opinion to share. They are a moisture magnet and very difficult to clear the water out of. Sorry, I know that's probably not what you wanted to hear.

 

[OI812]

Having worked in a shop that had buried lines I have an opinion to share. They are a moisture magnet and very difficult to clear the water out of. Sorry, I know that's probably not what you wanted to hear.

I agree 110% with that. If you are going to bury the lines, you should go below the frost line. If you don't want to do that then you styrofoam over the top and on the sides of the line. In the end moisture will still be a problem.

 

[Wile1Coyote]

I agree buried lines will give you a moisture headache

 

[bdaz442]

I was planning using PVC in my new shop. I went to several web sites by typing in compressed air piping on google. these are the web addresses.
http://www.ecompressedair.com/library/piping.shtml
http://www.sharpe1.com/dr-pipe.htm
http://www.woodweb.com/knowledge_base/Compressed_air_delivery_system.html
IMHO I would not use PVC, I'm using 3/4" copper for my main line with 1/2" drops.

 

[Luckydevil]

Good links! I'm adding them to my other compressed air resources post.

 

[OI812]

bdaz442

Great links with good diagrams. This should help a lot of people out.

 

[rickairmedic]

For those of you's using copper for air lines in your garages wanting too know what type of solder too use I am in the HVAC industry and the standard today in that industry is a product called staybright #8 it is a soft solder and has a low melting temp but is far stronger than standard plumbing type solder .You wont find it in any box stores but if you look in your local yellow pages for HVAC suppliers you should be able too find someone local who sells it . We quit using stick silver years ago due too the impurities on the inside of the pipe that result from the higher temps needed too work with it . The average presure on the high side of a residential HVAC system is between 225 and 250 pounds of pressure although I have seen the little buggers running at 400 too 450 . THe new puron systems have a high pressure side reading in the 350 too 450 PSI mark and so far no problems with the staybright#8 with it either .I am getting ready too run air lines in my garage as well and its what I will be using on my copper .MOST important part of soldering copper pipes together is making sure the joints are CLEAN CLEAN CLEAN and tight

Rick

 

[OH-MAN]

Any standard solder will work . No need to braze it
Since it is not for water you can even use 50/50 with the deadly lead in it, if you can find it. Most solders you can get now are of the 95/5 type and they are fine as well .
Just use a good flux and clean the joints before you do it. If you insist on brazing it will oxidize the inside of the pipe and leave a black flakey **** in the pipe. To prevent this you can purge the line with nitrogen or argon. Not worth the trouble.
Just soft solder it.

 

[rickairmedic]

OH Man the staybright#8 I was refering too is a soft solder it is used primarily in HVAC work where we dont want any **** in the lines and have become too lazy too purge with nitrogen


Rick

 

[bmwpower]

Ok, this info is great!

One question: How do you slope the pipe and still maintain plumb drops? One diagram mentions 4" drop per 50 feet. Can you simply bend the copper pipe to maintain is plumbness? Or do they make angled tees for such an installation?

 

[OI812]

A tee and one 90 will get you a plumb drop. Tee into main, and pipe over to wall and drop with a 90. The 90 is what will allow it to go plumb again.

 

[bmwpower]

Ahh. OK, got it now.

 

[bdaz442]

i have ask about this on other forums. All I can say is I'm using copper. Its got to be better that galvanized, and much easier than Black pipe. Cheaper too. Thats My 2 cents. LOL.