PEX marketed as COMPRESSED AIR line.

[fflintstone]

In my current issue of “farm show” I found an article about pex marketed specifically for compressed air. It is called DURATEC AIRLINE and sold by IPEX USA LLC. Sizes run from 3/8” to 1”.
100 feet of 3/8” is $120 and the fittings start @ $10 A little too pricy for me.
Still hoping to use copper.

http://www.ipexamerica.com/Content/Products/MarketSegment.aspx?MarketSegmentId=1#Compressed Air

in Canada: www.ipexinc.com

Generically this is called pex-al-pex if you want to look for a cheaper source.

I do not indorse this product or its installation, just providing information.

 

[Crusty Nut]

Even for 3/8" it is still expensive and way to small for any long runs. It also doesnt cool the air like a metal pipe will, so it won't pull any moisture.You can't get moisture out of warm compressor air.
It's interesting and I'm sure someone will buy it, but I'll stick with iron or copper.

 

[fflintstone]

Even for 3/8" it is still expensive and way to small for any long runs. It also doesnt cool the air like a metal pipe will, so it won't pull any moisture.You can't get moisture out of warm compressor air.
It's interesting and I'm sure someone will buy it, but I'll stick with iron or copper.

Well the aluminum in the line may help with condensation, I don’t know.
Before I new the evils of PVC I was going to run 3” pipe to have a “manifold” effect for extra volume. Now I have a much bigger compressor I don’t need extra volume. I will be dragging hoses along the floor for a while. I hope to one day have over 100’ of pipe and 4 drops in my shop.

Someone Recently asked about pex, and this article came up.

 

[romoman]

If you are worried about moisture you should have a drier, not count on the piping.

 

[PaulR]

When I do mine I think I'm going to start with 1/2 black pipe for around the compressor and along the center spine, then all the drops along the walls I'll switch over to pex al pex. It all looks really cool in my head.

 

[Mikea57]

fflintstone,
Farm Show magazine is GREAT!!! What an incredible collection of great, off the wall, DIY, pieces of equipment and ideas.

Sorry to digress, now back to your regularly scheduled conversation...

 

[darkk]

In my current issue of “farm show” I found an article about pex marketed specifically for compressed air. It is called DURATEC AIRLINE and sold by IPEX USA LLC. Sizes run from 3/8” to 1”.
100 feet of 3/8” is $120 and the fittings start @ $10 A little too pricy for me.
Still hoping to use copper.

http://www.ipexamerica.com/Content/Products/MarketSegment.aspx?MarketSegmentId=1#Compressed Air

in Canada: www.ipexinc.com

Generically this is called pex-al-pex if you want to look for a cheaper source.

I do not indorse this product or its installation, just providing information.

Pex is Pex you can use plumbing Pex for air line. Don't buy those kits for lots of money. Check out the prices at this vendor. IUt is where I purchased all my Pex for water and air plumbing. Look under plumbing. 100 foot of 3/4" is only $49.95 and the fitting are very cheap. You can buy the retainers/mounting brackets there also 100 pieces for $9.95
http://www.pexsupply.com/

 

[fflintstone]

Pex is Pex you can use plumbing Pex for air line. Don't buy those kits for lots of money. Check out the prices at this vendor. IUt is where I purchased all my Pex for water and air plumbing. Look under plumbing. 100 foot of 3/4" is only $49.95 and the fitting are very cheap. You can buy the retainers/mounting brackets there also 100 pieces for $9.95
http://www.pexsupply.com/

Pex IS NOT Pex!! Only PEX-AL-PEX (aluminum sandwiched by pex) is rated for compressed air.
I am not saying you cannot use regular pex, just that it is not RATED for or DESIGNED for air pressure.

 

[Charles (in GA)]

If you are worried about moisture you should have a drier, not count on the piping.

I agree, if you have moisture problems, do something about it, and don't expect piping to to do it for you.

Thanks to the OP for the IPEX links.

I am interested in the Dura-Plus "rigid" air line piping (ABS material) which is virtually identical to the discontinued Nibco ChemAir system. While it looks pricey, it really is not much more than iron pipe and much easier to install. I'm going to look more closely at this later in the year when the money catches up.

I downloaded and saved the manuals and price list. I'm sure I'll hear from them as you have to register to down load the manuals.

Charles

 

[keweenawbee]

Yikes, pex-al-pex is over six times more money at pexsupply.com. Are you saying it has a higher psi threshold, the oxygen barrier issue or what? Regular pex is tested and rated to 210 psi and 180 degrees. It has treated me just fine so far. I will probably take my chances with the regular stuff. I am especially thrilled with my direct burial cold climate results.

 

[fflintstone]

I agree, if you have moisture problems, do something about it, and don't expect piping to to do it for you.

Thanks to the OP for the IPEX links.

I am interested in the Dura-Plus "rigid" air line piping (ABS material) which is virtually identical to the discontinued Nibco ChemAir system. While it looks pricey, it really is not much more than iron pipe and much easier to install. I'm going to look more closely at this later in the year when the money catches up.

I downloaded and saved the manuals and price list. I'm sure I'll hear from them as you have to register to down load the manuals.

Charles

Keep us posted on the "ABS"! Since my air setup is 6 months or more down the line, I keep my options open. I like "easier" I don’t like “more expensive”.

 

[fflintstone]

Yikes, pex-al-pex is over six times more money at pexsupply.com. Are you saying it has a higher psi threshold, the oxygen barrier issue or what? Regular pex is tested and rated to 210 psi and 180 degrees. It has treated me just fine so far. I will probably take my chances with the regular stuff. I am especially thrilled with my direct burial cold climate results.

I don’t know why it is rated for compressed air and regular PEX is not.
There are many people on the board that get their ******* twisted about “rated for compressed air” I would guess that the aluminum is far less likely to burst if there was a manufacturing defect. It would give a bit more time in a fire setting.

 

[79firebird]

At my work we used the orange pex for infloor heating like 12 years ago and works fine a lot of outher shops now use the same came in looked at our setup and loved it. im running 1 1/2 from tank to tank and 3/4 drops at 200psi no probs

 

[mygarageone]

So can anyone tell me the difference between 120 lbs of water pressure and a 120 lbs of air pressure ? And if you have a water and oil separator at the discharge of compressor , why is oil in the lines a issue ?
So special air rated Pex is the only Pex that rated for air pressure and pressure is pressure correct ? Now tell me again what the difference is between 120 lbs of water pressure and 120 lbs of air pressure ?

 

[mygarageone]

I don’t know why it is rated for compressed air and regular PEX is not.
There are many people on the board that get their ******* twisted about “rated for compressed air” I would guess that the aluminum is far less likely to burst if there was a manufacturing defect. It would give a bit more time in a fire setting.

I'm with you on this . Now here 's a question , how many people us water ball valves for air lines . The valves are rated for wog water oil gas but I have never seen them rated for air , yet they use them for air all the time , why is that?

Nitch markets are popping up all the time and making it sound like they have the answer to what ever problem you have , when in fact they are using the same product like aluminum core Pex and calling it special Pex for air lines . This stuff has been around for years in the radiant heat industry but it's now blue in color and special for air only .
If anyone can show me the difference , I'm ok with that.

 

[tdkkart]

Now here 's a question , how many people us water ball valves for air lines . The valves are rated for wog water oil gas but I have never seen them rated for air , yet they use them for air all the time , why is that?

Because air is a gas??
It's AIR, what you use to valve it is not really all that critical, all you care is that it doesn't leak.

Some stuff gets way over-thunk around here.........

 

[C96]

All I can say is good luck all you Pex lovers.

Unless I’m missing something, I don’t know why you guys insist on using that **** for air lines. Just like years ago when people thought PVC was the way to go and guess what….

In my opinion, a shop is a harsh environment and no place for plastic plumbing of any kind especially compressed air. The Pex is to flimsy and would be impractical at service points unlike black pipe.

You would need to invest hundreds in a good air drying system as compared to what a good metal piping system will do. Without, you’ll be fighting an endless moisture battle with water sitting in all the sag points along the horizontal lines.

Bottom line, leave the Pex for connecting your ice maker and install a good quality metal piping system for the compressed air lines.

 

[DekeT]

So can anyone tell me the difference between 120 lbs of water pressure and a 120 lbs of air pressure ? And if you have a water and oil separator at the discharge of compressor , why is oil in the lines a issue ?
So special air rated Pex is the only Pex that rated for air pressure and pressure is pressure correct ? Now tell me again what the difference is between 120 lbs of water pressure and 120 lbs of air pressure ?

1 cubic foot of water at 120psi started out uncompressed at 1.00000001(edit;calculated @ 60F = 1.0004) cubic feet of water. 1 cubic foot of air at 120 psi started out as over 8 cubic feet of air. Now picture for yourself the energy stored in that 1 cubic foot of water versus the 8 cubic foot air compressed to 1 cubic foot. Now imagine a crack in the pipe of water. psssst.
Now imagine a crack in the pipe of air. BOOOOM!

Or look at it another way. It is very easy to compress a cubic foot of liquid to 120 psi. Think grease gun. It takes how many minutes of electric power to compress air to 120 psi? Now reverse that energy in a fraction of a second. That is your difference in gas pressure v liquid pressure.

 

[raddksn]

1 cubic foot of water at 120psi started out uncompressed at 1.00000001 cubic feet of water. 1 cubic foot of air at 120 psi started out as over 8 cubic feet of air. Now picture for yourself the energy stored in that 1 cubic foot of water versus the 8 cubic foot air compressed to 1 cubic foot. Now imagine a crack in the pipe of water. psssst.
Now imagine a crack in the pipe of air. BOOOOM!

Or look at it another way. It is very easy to compress a cubic foot of liquid to 120 psi. Think grease gun. It takes how many minutes of electric power to compress air to 120 psi? Now reverse that energy in a fraction of a second. That is your difference in gas pressure v liquid pressure.

We'll done!!!

 

[Kevin54]

Water pressure vs. air pressure.....Here you go....water is incompressible vs. air which is very compressible http://www.ejprescott.com/media/reference/PresTestwAirvsWaterR-25.pdf

ANd for the heck of it, another discussion on another site about the same thing http://www.brewcitymuscle.com/forum/showthread.php?23117-Stupid-question-Water-PSI-vs-Air-PSI

 

[littletoes]

For those of you who think "black" pipe was/is used in air piping because it helps remove moisture.....well let me say-you are WRONG.

We use black pipe in commercial applications because its CHEAP. Or...it WAS. And when engineers use black pipe, they ALWAYS oversize it at least ONE SIZE because Rust will block at least ONE THIRD of the cross section of the pipe in less than 20 years....depending upon if you use an air dryer or not (refrigerated that is).

I try and use galv. piping in commercial air piping (threading isn't a problem for us), but copper is better, if you can afford it. We have miles upon miles upon miles of copper in over 67 buildings....or I should say we "had"....everything is going DDC these days. Of course that is a different application....

 

[LS6 Tommy]

I think someone probably already said this, but I'll post anyway. That stuff in the magagzine link is PEX-AL-PEX. It's been around a long time and it's the ONLY PEX product certified for compressed air, period.

Tommy

 

[914wilhelm]

Biggest problems I've seen with plastic airlines is the first 20' from the compressor. This first 20' is subject to some vibration but more importantly heat. In one application a plastic airline was growing blisters right after the compressor and popping. That initial line was exceeding 200 degrees. Use 20' of metal line to shed some heat first.

 

[DangerousDan55]

The difference between water pressure & air prissure.

When water in a vessel or pipe is under pressure, the voulmn is the same. and where is a break, the "stored" pressure drop to zero is instant. resulting in no personal injury.


When air in a vessel or pipe is under pressure, the voulmn is increased. and where is a break, the "stored" pressure drop to zero is a long time period. resulting in a continued pressure & voulmn release which acts upon the pipe to further open the weakend break area. this produces fragmentation of the pipe\vessel & personal injury is increased.

thus the reason for the "HYDRO TEST" on piping & vessels before they areput into service.
Hydo test is used with water for the exact reason stated above.

 

[jpinca]

I see many discussions get wound around the axle here about whether something is "rated" for this or that. I've been doing global certifications in a particular (not really garage-related) industry for 15 years, so I have a little behind the scene experience.

I can tell you 100% that "not-rated for" and "not suitable for/ dangerous" are not necessarily the same.

A rating only means that the manufacture has evaluated an item for a particular application and sometimes has gotten specific certifications for that application. Often the inside lawyers will require a certification and those aren't free. I can easily spend $100k on all the testing and documentation for one product model; then another $5-10k for annual fees.

There are many reason why a manufacture would or would not rate their product, not all of them are technical.

Using the "non-rated for" argument doesn't advance, IMHO, the garage sciences.

The PCV topic is a good example. It has been covered well and the risks should be easily understood at this point.

 

[cat06]

if you go to the link, also listed is Duraplus airline. Rated for 185 psi compressed air. and it's cheap

http://www.ipexamerica.com/Content/...?ProductId=60&SubMarketId=9&MarketSegmentId=1

sold here

http://www.alscoplastics.com/ipex_duraplus_s/57.htm

 

[Skyjack]

I guess I missed the evils of pvc, what is the problem with using pvc for air lines?
Thanks

 

[jwith68]

1 cubic foot of water at 120psi started out uncompressed at 1.00000001(edit;calculated @ 60F = 1.0004) cubic feet of water. 1 cubic foot of air at 120 psi started out as over 8 cubic feet of air. Now picture for yourself the energy stored in that 1 cubic foot of water versus the 8 cubic foot air compressed to 1 cubic foot. Now imagine a crack in the pipe of water. psssst.
Now imagine a crack in the pipe of air. BOOOOM!

Or look at it another way. It is very easy to compress a cubic foot of liquid to 120 psi. Think grease gun. It takes how many minutes of electric power to compress air to 120 psi? Now reverse that energy in a fraction of a second. That is your difference in gas pressure v liquid pressure.

Water pressure vs. air pressure.....Here you go....water is incompressible vs. air which is very compressible http://www.ejprescott.com/media/reference/PresTestwAirvsWaterR-25.pdf

ANd for the heck of it, another discussion on another site about the same thing http://www.brewcitymuscle.com/forum/showthread.php?23117-Stupid-question-Water-PSI-vs-Air-PSI

For those of you who think "black" pipe was/is used in air piping because it helps remove moisture.....well let me say-you are WRONG.

We use black pipe in commercial applications because its CHEAP. Or...it WAS. And when engineers use black pipe, they ALWAYS oversize it at least ONE SIZE because Rust will block at least ONE THIRD of the cross section of the pipe in less than 20 years....depending upon if you use an air dryer or not (refrigerated that is).

I try and use galv. piping in commercial air piping (threading isn't a problem for us), but copper is better, if you can afford it. We have miles upon miles upon miles of copper in over 67 buildings....or I should say we "had"....everything is going DDC these days. Of course that is a different application....

I see many discussions get wound around the axle here about whether something is "rated" for this or that. I've been doing global certifications in a particular (not really garage-related) industry for 15 years, so I have a little behind the scene experience.

I can tell you 100% that "not-rated for" and "not suitable for/ dangerous" are not necessarily the same.

A rating only means that the manufacture has evaluated an item for a particular application and sometimes has gotten specific certifications for that application. Often the inside lawyers will require a certification and those aren't free. I can easily spend $100k on all the testing and documentation for one product model; then another $5-10k for annual fees.

There are many reason why a manufacture would or would not rate their product, not all of them are technical.

Using the "non-rated for" argument doesn't advance, IMHO, the garage sciences.

The PCV topic is a good example. It has been covered well and the risks should be easily understood at this point.

Excellent posts, all! Best discussion of compressed air piping and the science/engineering behind it that I have seen on this forum. I will add one point concerning PEX: regular plumbing PEX is not UV resistant. It comes with a warning about leaving new coils out in the sun for any length of time during construction. I don't know if the IPEX air line or regular PEX-Al-PEX is made UV resistant or not, but I would hope the air line rated material is. Many air lines are exposed, not run inside walls (mine included) and a couple of mine do catch direct sunlight at times.

I guess I missed the evils of pvc, what is the problem with using pvc for air lines?
Thanks

Not touching this one with a specially constructed 11 foot pole. Do a search on here for "PVC air lines" and you will find the most contentious arguements you have ever seen on here. Bottom line: don't do it.

 

[mygarageone]

1 cubic foot of water at 120psi started out uncompressed at 1.00000001(edit;calculated @ 60F = 1.0004) cubic feet of water. 1 cubic foot of air at 120 psi started out as over 8 cubic feet of air. Now picture for yourself the energy stored in that 1 cubic foot of water versus the 8 cubic foot air compressed to 1 cubic foot. Now imagine a crack in the pipe of water. psssst.
Now imagine a crack in the pipe of air. BOOOOM!

Or look at it another way. It is very easy to compress a cubic foot of liquid to 120 psi. Think grease gun. It takes how many minutes of electric power to compress air to 120 psi? Now reverse that energy in a fraction of a second. That is your difference in gas pressure v liquid pressure.

So how does that alter the pressure ? There still the same pressure and you are talking about stored energy , pressure is still the same . If the pipe is rated for
x #' s . Stored energy will not effect the pressure rating.
You are stating what would happen with a crack with stored energy , pressure doesn't 't change . The resulted of stored energy is what your concerned about.
The arguments against any new product has gone on for yrs. when PVC first was introduced by the industry for drainage piping , the plumbing industry went nuts , claiming that all kind of calamities would result because of it , yes that was when it first came out , none of it ever materialized . The na Sayers have always tried to hinder progress.
Taking risks is what built this nation to what is today , if not for risk takers we would never have made it to the moon.
Trail and error , it will shake it out one way or the other. I for one am glad the people who didn't want the horseless carriage built didn't get there way. And the list goes on and on.

 

[Mr onetwo]

All I can say is good luck all you Pex lovers.

Unless I’m missing something, I don’t know why you guys insist on using that **** for air lines. Just like years ago when people thought PVC was the way to go and guess what….

In my opinion, a shop is a harsh environment and no place for plastic plumbing of any kind especially compressed air. The Pex is to flimsy and would be impractical at service points unlike black pipe.

You would need to invest hundreds in a good air drying system as compared to what a good metal piping system will do. Without, you’ll be fighting an endless moisture battle with water sitting in all the sag points along the horizontal lines.

Bottom line, leave the Pex for connecting your ice maker and install a good quality metal piping system for the compressed air lines.

Amen brother!!! Why can't you guys just do it the correct way! Type L copper 1st choice and black iron 2nd.

 

[MP&C]

Plastic lines will not stand up well in the event of a fire, like the THREADED fittings on steel will. Let your plastic line melt, and the compressed air that escapes will soon have an inferno going. See this for a sample.

http://www.project33.com/article.cfm?ID=69

 

[buddyboy]

So how does that alter the pressure ? There still the same pressure and you are talking about stored energy , pressure is still the same .

it doesn't alter the pressure.

would you rather get sprayed by a firehose @ 10lbs of pressure and 10 gallons of water? or 10 lbs of pressure with 1000 gallons of water.

think of it as the pressure being the same but the volume is more.

another example is if you had 2 springs, one with tight coils one with loose coils... to compress both springs to the max might take the same amount of pressure but one spring will decompress 1 foot, the other 10 feet. (well something like that lol)

 

[rlitman]

Plastic lines will not stand up well in the event of a fire, like the THREADED fittings on steel will. Let your plastic line melt, and the compressed air that escapes will soon have an inferno going. See this for a sample.

So will a rubber hose. It get's pretty difficult to use an impact gun when it's screwed into your steel pipe. Even if you use a lot of elbows to make swing joints. Or are you suggesting I replace my air hoses with CSST stainless corrugated tubing?

Your argument is not realistic.

 

[finn]

Quite a few people didn't pay attention in physics class in high school

 

[MP&C]

So will a rubber hose. It get's pretty difficult to use an impact gun when it's screwed into your steel pipe. Even if you use a lot of elbows to make swing joints. Or are you suggesting I replace my air hoses with CSST stainless corrugated tubing?

Your argument is not realistic.

My post and the link provided discussed residual pressure in the lines and possible fires in the shop. For my shop practices, I disconnect all my rubber hoses when not in use, and especially when leaving the shop, so for me I feel that the black steel pipe and threaded fittings give me the best scenario at maintaining an intact air system in the unfortunate event of a fire. I don't know how you run your operation, so only you can determine if the corrugated stainless tubing will help you or not..

 

[DekeT]

So how does that alter the pressure ? There still the same pressure and you are talking about stored energy , pressure is still the same . If the pipe is rated for
x #' s . Stored energy will not effect the pressure rating.
You are stating what would happen with a crack with stored energy , pressure doesn't 't change . The resulted of stored energy is what your concerned about.
The arguments against any new product has gone on for yrs. when PVC first was introduced by the industry for drainage piping , the plumbing industry went nuts , claiming that all kind of calamities would result because of it , yes that was when it first came out , none of it ever materialized . The na Sayers have always tried to hinder progress.
Taking risks is what built this nation to what is today , if not for risk takers we would never have made it to the moon.
Trail and error , it will shake it out one way or the other. I for one am glad the people who didn't want the horseless carriage built didn't get there way. And the list goes on and on.

I don't see how my simple pressure versus potential energy story has anything to do with what you are talking about as far as scientific progress and what this nation is today. Save the rant for a more applicable topic.

Drainge is open channel flow subject only to the pressures of elevation head and kinetic energy. That is an entirely unrelated and different book on hydraulics. Like apples to elephants difference. The whole point of this pvc thing is NOT that the pressure is the same. We all know the pressure is the same. The POINT is the consequences of using the incorrect material for storing it.

By all means if you want to use pvc for airlines go ahead it's your choice. Cooler heads will use a safer material. Even the industry manufactures warn against the use of pvc for alr pressure so your trial and error assertion is groundless in this case.

 

[Kevin54]

In a way also, and i may be way off base on this, but figure the pressure on a garden hose. If a garden hose is coming out at 30lbs. PSI, you can put your thumb over the end and stop the flow. If you have 30 lbs. PSI coming out of an air hose, you can't stop the flow without leaks.

Now look at a lot of wide tires on a lot of the off terrain vehicles. They only run maybe 10 lbs. of pressure. A lot of the vehicles in the Arctic, run very low pressure. They can use a little bit of spray, light it, it pops the bead back on, and they are good to go.

I know I'm not explaining it right, but possibly if there are any railroaders on here, they can explain some of it. I remember my dad years and years ago having to learn all about air pressure because of the brakes on trains.

Damn i wish i had studied some stuff in school a little bit more. It starts to get a little complicated when it starts to get into hydraulic pressure using hydraulic oil, verses water pressure, verses air pressure and the compressible difference between all three.

If I remember right from what my dad explained to me was that air can be compressed faster than hydraulics and with that is one reason it builds up heat. Hydraulics using oil has a higher viscosity and can compress more but does not generate the heat that air does and is slower because of the viscosity. Water falls in between the two.

And with air having a pressure that is high, but not much viscosity, the release of it is more powerful than water or air.

Like i said, I wish I had paid way more attention years back and these are just bits and pieces of what I sort of remember my dad telling me when he had to study it. I may be way off.

 

[mygarageone]

I don't see how my simple pressure versus potential energy story has anything to do with what you are talking about as far as scientific progress and what this nation is today. Save the rant for a more applicable topic.

Drainge is open channel flow subject only to the pressures of elevation head and kinetic energy. That is an entirely unrelated and different book on hydraulics. Like apples to elephants difference. The whole point of this pvc thing is NOT that the pressure is the same. We all know the pressure is the same. The POINT is the consequences of using the incorrect material for storing it.

By all means if you want to use pvc for airlines go ahead it's your choice. Cooler heads will use a safer material. Even the industry manufactures warn against the use of pvc for alr pressure so your trial and error assertion is groundless in this case.

I never advocated PVC air lines .
You went on about stored energy , which has nothing to do with , will reg Pex. Handle air pressure ..? Your issue is if it fails , that was not my question.
If and have failed are two different issues and Phic's does apply to stored energy . I was not arguing about that at all. My whole point was 120 # of pressure is 120# no matter what is making the pressure.

 

[dbonne]

I've been using 3/4 pex for air lines for a while. No problems.

 

[DekeT]

I never advocated PVC air lines .
You went on about stored energy , which has nothing to do with , will reg Pex. Handle air pressure ..? Your issue is if it fails , that was not my question.
If and have failed are two different issues and Phic's does apply to stored energy . I was not arguing about that at all. My whole point was 120 # of pressure is 120# no matter what is making the pressure.

You are correct, 120 psi is 120 psi no matter what is causing it. In the same vein that a pound of gold is the same as pound sand.