[Five-10]

Anyone here using PVC pipe for their compressed air lines and if so how does it work? Copper is so expensive these days and steel always rusts inside.I just bought a building and will be moving in soon. It isn't plumbed for air. I have a 40hp screw compressor with a backup 30hp screw feeding 5 cnc machines.

[Geof]

No emphatically not!!!!!

Apart from causing heart attacks to any safety inspectors that come by it is far too dangerous.

When PVC fails under pressure it goes with a real bang and cracks propagate through the lengths of pipe very fast. You have a very good chance of filling your place with PVC shrapnel moving very fast.

There are no simple plastics that are safe for compressed gases. If you wanted to use a carbon fiber reinforced composite that might work..at many times the price of copper.

Use copper or galvanized. You should have a dryer on your compressor for CNC machines so with this there should be no water in the air to rust galvanized.

[JEFFY]

DON'T EVER USE PVC FOR AIR LINES! Geof is right, pvc and air is like vineger and oil.
If you don't believe me go to any of the plastic fitting company's web sites(Nibco, Lasco, Spears, Mueller ect)they all say "DON'T USE ON COMPRESSED AIR/GASES" I worked in the plumbing industry for years and none of the manufactures approve of its use on any compressed gases.
If you want to see plastic fail, put a foot or two of pvc in your freezer for a couple of hours then drop it on the floor. It will shatter just like glass.
Please note, that this applies to hard plastic that is glue or threaded together.
If you really want plastic, look into flexiable plastic tubing(like the brake lines on semi-trucks) I myself use copper in my shop.
Please read the following link
http://www.spears.com/tech_updates/T...No.106_web.pdf
http://www.spears.com/prod_dimension..._0206.indd.pdf
http://www.lascofittings.com/support...pressedAir.asp

[Caprirs]

PVC is unsafe and illegal to use for air lines.

The key is as Geof stated, the explosive (not combustion, but rapid expansion) nature of compressed gases. PVC is rated to high pressure for liquids because liquids under pressure are not compressible. If you have a crack in a water line, you'll get a fountain which is annoying but not dangerous. The same crack in a PVC air line will cause the plastic to splinter and shatter because once vented, the compressed gas keeps trying to expand.

[mactec54]

Five-10
There is a plastic pipe you can use it is Duraplus ABS Airline Pipe it is
OSHA aproved and you can get it from ( IPEX ) This is designed for compressed gases this will not shatter like PVC can

[Geof]

Five-10
There is a plastic pipe you can use it is Duraplus ABS Airline Pipe it is
OSHA aproved and you can get it from ( IPEX ) This is designed for compressed gases this will not shatter like PVC can

I stand corrected, Thank You.

I checked and found the Duraplus is rated at 185psi up to 73F and they also have a Duratec that is rated 160psi at 140F.

Now all I have to do is find a supplier and see how the price compares to copper or galvanized. It should certainly be easier to install.

The IPEX website does say it is a new product; I wonder how new.

[tobyaxis]

Anyone here using PVC pipe for their compressed air lines and if so how does it work? Copper is so expensive these days and steel always rusts inside.I just bought a building and will be moving in soon. It isn't plumbed for air. I have a 40hp screw compressor with a backup 30hp screw feeding 5 cnc machines.

No Way!!!!!!!! I saw some JackA$$ do this in a shop and while a co-worker was next to one of the lines it exploded. He is deaf in one ear now. Not to mention the scars on his face and ear.

Never Ever Do This!!!!!!!!!! The Dangers are far too great to take the cheap way out.

That new product might work better but never use PVC.

[Geof]

I should make it clear; this is the only sentence I stand corrected on:

"There are no simple plastics that are safe for compressed gases."

[tobyaxis]

I should make it clear; this is the only sentence I stand corrected on:

"There are no simple plastics that are safe for compressed gases."

Sorry my post was windy. Yours is simple and to the point.

BTW: your up too 3000 posts.

[Geof]

Sorry my post was windy. Yours is simple and to the point.

BTW: your up too 3000 posts.

And you say you are the windy one; you are an amateur when it comes to windy.

[tobyaxis]

And you say you are the windy one; you are an amateur when it comes to windy.

Well, unfortunately I lack experience and age LOL. I won't ever catch up to you but some day be as windy as you are now LOL.

Cheers!!!!!:cheers:

[Five-10]

OK, I decided to go Copper. Max Machine cuts no corners machining so I'm not going to start cutting corners with my new building. By the way my Haas service tech is the one that mentioned pvc to me. He's was complaining about rust in my steel lines as he was replacing the leaky regulator on my new VF6SS.

[Geof]

... rust in my steel lines as he was replacing the leaky regulator on my new VF6SS.

Get a good dryer, it is worth it in the long run. When a solnoid faults because of water in the air you can lose the cost of the dryer very quickly.

[Five-10]

I should have mentioned in my first post that I have an air dryer (325 SCFM) So I don't really get any water in my lines. This building I'm in now was a tractor trailer repair shop and The airlines were in place when I leased it. They didn't have an air dryer and the steel pipes are all rusted inside.

[Geof]

Oh so you blew rust particles into your machines without knowing it? That is a nasty lesson to learn; don't use existing airlines without a detailed inspection.

[ger21]

The IPEX website does say it is a new product; I wonder how new.

We've had Duraplus air lines in our shop for 8-9 years or so. Haven't had any problems with it.

[P J]

At maximum operating temperature for PVC (140ºF, 60ºC) the strength is derated to approximately 20% of the strength at 73ºF (23ºC). For CPVC the strength is reduced to 20% of the initial strength at 200ºF (93ºC). PVC is degraded by sunlight further weakening it.

For threaded fittings, derate to 50%

For cold regions, derate at least 50% depending upon temp. Ask any spud gun advocate why he doesn't shoot in the winter time.

This is far too great a hazard to save a few bucks. Keep in mind, copper is easy to install, modify, and later remove. And, it's reuse and/or scrap value increases with time. Think of it as a long term investment.

[Geof]

.... Ask any spud gun advocate why he doesn't shoot in the winter time....

Spud gun advocates should be using ABS pipe

ger21; I had never bumped into Duraplus and I never bothered searching for rigid plastic airlines because I never expected to find anything.

[P J]

I agree wholeheartedly. You are obviously aware of the hazards. Good for you !

[mecheng9]

Five-10,

It sounds like the copper is a good idea and a good air filter and drier.

regards,

Mecheng9