PEX air lines?

[jack stand]

Sorry if this has been covered, I did not get any results searching, but that was before I signed up. In my last shop I used copper, but after using the PEX for my new home and for the radiant heat, I'm quite impressed with it. I'm thinking that I''ll stub into the shop (the compressor will be outside in a big "lean too" shed in an enclosure) with copper for a direct un-regulated (175psi) point of use, and bring another (regulated) line of 3/4" pex to feed the 1/2" drops for the regular quick connect fittings. I'll prolly transition back to either black pipe or copper to come thru the wall and support the connector. I know about pitching the lines for cond. and providing several "dip legs" in line and at the end. Any body used PEX?

 

[ratdoggy]

Sorry if this has been covered, I did not get any results searching, but that was before I signed up. In my last shop I used copper, but after using the PEX for my new home and for the radiant heat, I'm quite impressed with it. I'm thinking that I''ll stub into the shop (the compressor will be outside in a big "lean too" shed in an enclosure) with copper for a direct un-regulated (175psi) point of use, and bring another (regulated) line of 3/4" pex to feed the 1/2" drops for the regular quick connect fittings. I'll prolly transition back to either black pipe or copper to come thru the wall and support the connector. I know about pitching the lines for cond. and providing several "dip legs" in line and at the end. Any body used PEX?

Don't know about PEX but newer trucks use plastic tubing for their airlines. It's pretty cheap and is plenty strong. Look into that.

 

[mordantly]

PEX is only rated something like 100psi... my 2007 built house has PEX water lines and they don't like to freeze or UV exposure! why not 1/2" PVC? it's rated >300psi WP, and about 2000psi burst.

 

[tonycastec]

I suggest you research pex-al-pex. It has a working pressure of 200psi in 1/2". There is generic pex-al-pex and some proprietary version like Maxline from Rapid air.
The aluminum core (Hence the "AL" in pex-al-pex) gives it the extra strength. It also helps to straighten it from the coil.
One issue with the generic pex-al-pex is that it is very difficult to find online coils less than 300 ft in 1/2" .You can get 3/4" in 100' but not 1/2".
The fittings for the proprietary systems are usually push-fit ,so it goes together fast (legris?). I'd be inclined to use the generic compression fittings.
Let us know what you decide to use and how it goes?

 

[rburke65]

mordantly.......did you just say to use PVC for an airline!!!!!OMG!!!

 

[diggerrick]

Our shop uses a lot of 1/2" nylon tubing:

http://www.camozzi-usa.com/documents/fittings/tubing/nylon-11-tubing.pdf

with push lock fittings:

http://www.camozzi-usa.com/documents/fittings/fittings/nickel-plated-brass-push-in-fittings.pdf

for industrial pneumatic equipment.

It's way easier to work with than iron or copper pipe.

 

[jcp907]

I used pex in every junction in my attic (~60' worth or so). The research I did tells me that if we keep it shielded from UV it should be fine. I used the crimp ring connectors. Everything I could find shows that it's rated above the 90 psi that I run my lines at. If I recall correctly, it's marked 150.

I used Black pipe for everything in the shop. Primarily to try to pull as much water out of the air as possible. The shop is air conditioned so that should also help.

I also have Pex for my water, overhead. I figure if I trust it to hold water, I can trust it for air. And it in the case of a failure, it won't cause shrapnel unless it becomes brittle.

 

[G_P]

Just be aware that exposure to UV light will seriously weaken PEX pipe. I used to work at a place that sold it and the short sticks of it came packed in thick black bags with warnings all over it to avoid exposure.

Bad idea to use it for compressed air if you have a lot of windows in your shop or if you do a lot of welding in there.

Be wary if you pick any up off of craigslist too. If its not wrapped in black plastic you have no way of knowing if it has been sitting out in the sun or not.

 

[pattenp]

mordantly.......did you just say to use PVC for an airline!!!!!OMG!!!

Kinda hard to believe isn't it?

 

[mordantly]

mordantly.......did you just say to use PVC for an airline!!!!!OMG!!!

YES! i've had to run air 200 feet, so i buried sch 40 1/2". just checked.. it's rated 600psi WP.

 

[pattenp]

PVC under ground for air is probably okay. PVC is dangerous when used for air pressure because it can explode and throw pieces that can injure. The way PVC acts under water pressure vs air pressure when it ruptures is different. The manufacture of PVC states it is not to be used for air systems.

 

[DIC]

pvc?....here we go

 

[slip knot]

I've read a bit about Pex and its UV issues. But a few years ago we put in a gaurd house at the gate and ran pex out to it. We intended for this to be a temp situation so we just ran the pex up the back wall and into the building. No insulation or covering at all, its temporary rememeber. I was inventorying structures with the insurance last week and when we got to the back of the gaurd house I noticed the Pex was still there and still looked as good as new. Was kinda suprised that it was in as good shape as it was. I had completely forgotten about it!

 

[pattenp]

It's like throwing a piece of red meat into the lions den.

pvc?....here we go

 

[Alchymist]

...............................

 

[Will67]

Ibtl

 

[waltmcq]

The pex I just used for a water lines says 130psi on it.

 

[collmorgen]

We use pex in our plant for instrument air. We discovered the hard way that the clear is not UV stable but the black is.

 

[uncletater]

PEX is only rated something like 100psi... my 2007 built house has PEX water lines and they don't like to freeze or UV exposure! why not 1/2" PVC? it's rated >300psi WP, and about 2000psi burst.

100psi at 180 degrees. 160psi at 74 degrees

I also am planning on using pex. I spoke to the rep at the plumbing supply house. He claims it would be fine and he even uses it in his home shop. I asked about UV and he stated put it in the wall or use foam insulation. I think you will be fine. if it breaks it splits not explodes. Pex is easy and cheap just to add use the copper fittings not the new plastic ones. they ****.

 

[djjsr]

I checked with my local plumbing supply company and they told me Pex was not to be used for air.

The PexSupply.com website has a toolfree number and an online chat you could use to get accurate information.

http://www.pexsupply.com/resources

 

[jack stand]

Yep, i'm stuffing it in the wall and going for it. I already have the crimp tools for the rings after using it on my radiant and dom. water. The stuff is so cheap ($$) that if you were really worried, you could make "home runs" back to an acessable manifold (the typical plumbing set up) to have no, or few hidden fittings in the wall.
BTW, I'm folowing "WRIGHT TOOL's) therad from Aug. 09 on rebuilding cheapo chineese floor jacks. Just now ripping into one. Is he still around? for parts? 3 years too late but thanks for that generous detailed write up!

 

[ME87]

McMaster has a whole arrangement of poly and nylon tubing rated for pressures as high as 1,000 psi.

http://www.mcmaster.com/#vacuum-tubing/=gh3ilf

They carry every push connect fitting (better quality than Rapid Air) known to man, in an assortments of prices and qualities depending on your budget.

http://www.mcmaster.com/#catalog/118/185/=gh3jqk

Just finished getting my system useable

In the end it costs me a bit more than a rapid air kit would, but I feel the quality is better as all of their elbows and T's are plastic which inferior seals.

 

[djjsr]

I just got off a chat session with the tech guy at PexSupply. I told him that I assumed pex was not ok for air line and wanted him to confirm or deny.


You are now chatting with 'Mark'

Mark: Hi Don. You are correct. Pex is not rated or tested for use with air. I'm not sure if we have anything on our website stating that though.

Don: Do you know anything about pex-al-pex?

Mark: I have some knowledge on that tubing, how can I help?

Don: I understand it's reinforced with aluminum tubing and ok for air.

Mark: It is reinforced with aluminum. As with standard pex, Pex-al-pex is not rated or tested for use with air. It's possible it may work but since that is not the application it is made for I have no information on that.

Don: ok, thanks Mark.

end



Sooooooo, seems like pex is a lot like pvc. Probably safer though, I doubt it will throw plastic shrapnel if it blows.

 

[ME87]

Post 10 has some useful info for you directly related to PEX as well

http://www.sawmillcreek.org/showthread.php?46903-pex-tubing-for-compressed-air-lines

 

[Zick]

Just because PEX has not been "Rated" or "Tested" doesn't mean it won't work, it just means that nobody has tested it thoroughly enough to get a rating.

 

[tonycastec]

We need to be clear about our apples and pomegranates here.
Pex and pex-al-pex are not the same item. Pex-al-pex when branded as Duratec by Rapid Air is rated as having a working pressure of 200 psi at 70 degrees.
http://www.rapidairproducts.com/duratec.asp
Plain Pex is much lower.See the website for details.

 

[darkk]

I just did a new addition with pex for everything. Pex is rated for more than 100 psi. I had to test my water lines at 135psi for a week. Pex is almost impossible to break by freezing.....It is really really strong...

 

[tonycastec]

I just did a new addition with pex for everything. Pex is rated for more than 100 psi. I had to test my water lines at 135psi for a week. Pex is almost impossible to break by freezing.....It is really really strong...

But a 2 stage compressor produces 175psi +
Hence the advice to use pex-al-pex.

 

[Motofixxer]

A while back I seen some blue pex at Menards that was rated 200psi. It wasn't the regular stuff they normally carry that's why I noticed it. I didn't pay close attention if it was Pex-AL-Pex or just regular pex. Just that that it was 200 psi.

There are numerous threads on this subject though.

 

[ME87]

But a 2 stage compressor produces 175psi +
Hence the advice to use pex-al-pex.

and Rapid air says to regulate pressure to 150 psi max.

 

[jack stand]

I believe that the "not rated or tested" for comp. air, is lawyer talk. And it it werent for lawyers, we wouldn't need lawyers!
I've used the PexAlPex (for radiant heat) and it definetly is stronger but quite ridgid and much more difficult to work with, not to mention much more costly. I think using it would put you into the price range of the McMaster Carr or Northern tool type material. As for the somewhat limited psi, none of my tools (or any that I can think of) use over 125-130 psi. whitch is in the PEX range.

 

[tonycastec]

and Rapid air says to regulate pressure to 150 psi max.

No they do not ! the link above says "200 psi Operating pressure for Duratec ! Duratec is pex-al-pex. Plain pex has a lower rating. The rating also depends on temperature and diameter of the piping.

 

[ME87]

Just so we're clear on the 3 products at hand from Rapid Air 2 HDPE AL Systems and one Nylon.

Standard Rapid Air

Maxline

The advertised pressure of 200 Psi is at a relatively low 73 degrees. You can imagine the leader line being exposed to much higher temperatures near the head of the compressor so a hardline out through the dryer/cooler might be prudent in the design here.

Duratec

and standard Pex

PEX

 

[Alchymist]

J

The advertised pressure of 200 Psi is at a relatively low 73 degrees. You can imagine the leader line being exposed to much higher temperatures near the head of the compressor so a hardline out through the dryer/cooler might be prudent in the design here.

]

Not to mention those who might run a line through an attic.

 

[jhelrey]

I'd like to see someone with a high pressure air compressor test PEX. Get a section, cap it off, pressurize it to 175 PSI, beat it, etc. see if it explodes

 

[djjsr]

I find it really hard to believe that the manufacturers of PEX haven't done any testing for air. There's a pretty big market out there that they could supply. Maybe they tested but weren't happy with the results? Dunno.

 

[Motofixxer]

I'd like to see someone with a high pressure air compressor test PEX. Get a section, cap it off, pressurize it to 175 PSI, beat it, etc. see if it explodes

Somebody send me a piece I will do it and record it then upload it for all to see.

 

[jhelrey]

I have 1/2 and I can test it to 155

 

[darkk]

But a 2 stage compressor produces 175psi +
Hence the advice to use pex-al-pex.

Who runs a line pressure of 175 psi in a residential setting? If you do, why? I have a 2 stage 5hp commercial compressor, I am a professional body man,painter,fabricator and have done serious body and custom work in my garage and I sure as **** don't run anything that requires that kind of air pressure.

 

[indymx6]

IMHO rapid air *****. No offense to anyone who has used it. I have 3/4 steel pipe in my set up. the only other option i remotely thought about was this Maxline set up. ITs big enough to carry volume where you need it and has great reviews.