PEX for air line

[nate379]

I was at the rubber shop today getting some prices. I need about 100ft of 3/4" air line to run from my compressor in my shed to my garage.

Rubber air line is $2.55/ft for 3/4". The guys there suggested maybe using PEX tubing instead. It's rated to 150psi and -40*. The biggest they had was 5/8" so I didn't get any, but the 5/8" was $0.75/ft

I'm wondering why I haven't heard of using PEX before?

 

[wantedabiggergarage]

I'm wondering why I haven't heard of using PEX before?

Maybe you haven't been reading all the line threads?

Regular pex, isn't rated for air. Pex-al-pex is.

 

[tcianci]

Hey, that's too short of an answer...lets get another 100+ post, plastic air line thread going, its been days since we have seen one!

 

[-B-]

Divide any liquid rated pressure by three and you get air/gas rating . Building any air system no matter the pressure you always want to go over the maximum working pressure you expect out of your source. IE compressor put out 125 psi you should build a system to for 200 psi working pressure it give you an additional safety over the burst pressure rating. My HPA set ups are 5/6k working pressure rated and my 4.5k system is 9/10k rated why ? well thing happen bumps, nicks, shock loads, and age.

 

[djd99]

I was at the rubber shop today getting some prices. I need about 100ft of 3/4" air line to run from my compressor in my shed to my garage.

Rubber air line is $2.55/ft for 3/4". The guys there suggested maybe using PEX tubing instead. It's rated to 150psi and -40*. The biggest they had was 5/8" so I didn't get any, but the 5/8" was $0.75/ft

I'm wondering why I haven't heard of using PEX before?

Northern tool sells a kit that's similar to pex that uses the push type fittings that looks really cheesy so I would think pex would work much better.

http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200367525_200367525

 

[nate379]

I said PEX not PVC. I searched on here an nothing on PEX for air came up.

 

[Stinger]

http://www.lowesforpros.com/get-to-know-pex

Pex won't produce shrapnel like PVC so the ramifications of a failure shouldn't be anywhere near as severe as PVC. While the Pex-al-pex is the correct tubing for air, it seems Pex would be fine in single stage compressor applications.

I sent an email to a company that supplies PEX (pexconnection.com) here is what he said when I asked about using PEX for compressed air in a hobby woodworking shop

" Air is routinely used for pressure testing PEX plumbing systems, and we use it here to distribute the air for our air compressor, so I would say that it should not be a problem for you to do that."

Then I asked about exposure to fluorescent lights in my shop. And his reply was:
"For best results, you will most likely need to cover it. PEX should not be exposed to direct UV light for more than 30 days. I will say, however, that the PEX we are using (for water and air) is exposed to direct fluorescent light and indirect sunlight and is performing well. Still, the recommendation is that it not be exposed to UV light."

 

[Torque1st]

Divide any liquid rated pressure by three and you get air/gas rating .

Not for PVC. It is not rated for gasses under pressure period.

 

[z28snksknr]

Divide any liquid rated pressure by three and you get air/gas rating .

I agree with your statement about safety margin in design, but for my own knowledge, where did you get this rule from and how is it substantiated? To me, a pressure rating is a pressure rating- liquid or air. As long as you account for pressure from liquid head in a vessel (being additional to static pressure), how would the actualy force on the vessel (or in this case tubing) be any different?

Does it have to do with how the material fails? If you include sufficient design margin into the system (20-30% above max operating pressure in my field), there shouldn't be any failure to begin with, correct?

 

[nate379]

So is rubber like the best thing to use?

Rubber line vs Pex is about $155 difference. That's alot of Ramen!

 

[bgott]

http://cgi.ebay.com/ebaymotors/250'...B-ORG-250_W0QQitemZ160346929560QQcmdZViewItem

This stuff is cheap and rated for air.

 

[Stinger]

http://cgi.ebay.com/ebaymotors/250'...B-ORG-250_W0QQitemZ160346929560QQcmdZViewItem

This stuff is cheap and rated for air.

What type of fittings do you use with that stuff?

 

[dragginblazer]

PTC (push to connect) fittings are the easiest

http://airridefittings.com/store/index.php

 

[bgott]

http://www.imperialsupplies.com/catG.shtml

There is some stuff here, also.

 

[Torque1st]

PTC are the easiest but compression fittings are also available. Any industrial supply house that handles fluid power components will have both types.

 

[Stinger]

Why don't more people go this route?

 

[nate379]

That isn't 3/4" though. The ID needs to be at least 3/4", and they are measuring the O/D of that hose. The price is decent, but $120 for shipping is down right retarded! I just shipped 400lbs of tires for not that much more than that!

 

[mrb]

rubber hose seems like a waste of $$$ for something like that

check out HDPE tubing. 1in OD / 3/4in ID is $0.70/ft at Mcmaster. 3/4in OD is like $0.30/ft but its only good for 125psi. This P/N is good for 195PSI 50375K57 , and HDPE tubing is appropriate for air service.

 

[wantedabiggergarage]

Nate,

Pex was discussed in a thread I believe you posted in. (If I am remembering you and not someone with a similar name) You said your father? had been using CPVC in the shop for years, and argued back and forth with someone about it. (if you know what I am talking about, see if you can find it)

Otherwise, this sites search engine verges on worthless. You can't search any free parking, can't use or find common terms, and even specific terms (like Pex-al-pex) are listed as not found. Yet go to google and type "Pex-al-pex site:garagejournal.com" (everything in the quotes) and you find multiple posts.
I hope this helps you for future searches.

 

[nate379]

Could be. I barely remember what I ate for supper 4 hrs ago, so something I posted a few months ago isn't anything I will remember!

 

[Dragster Racer]

Otherwise, this sites search engine verges on worthless.

I'm glad someone else said it. Everyone says "use the search!" This site has the worst search I have ever used. You will spend a half hour weeding through the chaf to get to any decent information, which this site has a bunch of. Maybe I just don't know how to use it, but I get good results on other sites.

 

[collmorgen]

I'm a plant manager of a small chemical plant and we have been using PEX tubing with push to connect fittings for five years now for all of our instrument air. We haven't ha any problems other than uv degradation with the clear tubing that was exposed to direct sunlight (no problem with it under uv lights). We have found the black tubing to hold up very well under direct sunlight.

 

[Torque1st]

Otherwise, this sites search engine verges on worthless.

I'm glad someone else said it. Everyone says "use the search!" This site has the worst search I have ever used. You will spend a half hour weeding through the chaf to get to any decent information, which this site has a bunch of. Maybe I just don't know how to use it, but I get good results on other sites.

This site uses the same search functions as any other vBulletin site. Practice makes perfect. Use Google if you want a more robust search engine.

 

[wantedabiggergarage]

This site uses the same search functions as any other vBulletin site. Practice makes perfect. Use Google if you want a more robust search engine.

Multiple of my forums use the Vbulletin software. There ARE settings that can be adjusted. Some of them work MUCH better then this or others. Two examples are try searching this site, for a particular, short named brand, SK; not possible. The second example, we are in, Pex-al-pex. NOT found via this search engine, yet found via google. The Ford truck site I see you at, I have found it via their search engine.

 

[Torque1st]

Most forums do not index on 3 letter words or less. FTE used to limit their search the same way. I don't know what they do now. It is a setting that the webmaster can set. It makes it difficult to find abbreviations etc but usually searching with longer words will work. Use Google if you want to search easier.

 

[hawgputter]

Black pipe or copper (L or K) is the best!

 

[nate379]

Both of those are expensive. $2.55 for rubber line is pennies compared to either. Plus I already have the conduit 3ft underground.

 

[mrb]

Both of those are expensive. $2.55 for rubber line is pennies compared to either. Plus I already have the conduit 3ft underground.

did you look at the HDPE I suggested earlier in the thread?

 

[nate379]

I missed your post somehow, thanks for re posting because that looks like exactly what I need!

I just sent them a message to see what the shipping would be. I hope it's reasonable.

 

[mrb]

let us know what you find out

 

[Pointbock]

to see what the shipping would be. I hope it's reasonable.

Nate, you know that's a relative term for us up here.

I've been here almost 10yrs, and still get pissed about that.

 

[nate379]

Sure, but it's the $70 shipping for a 10lb item deals that really piss me off. You go on UPS, USPS, FEDEX and figure it out and it's maybe $15 shipping.... so.... who's making the money on that one?

 

[Torque1st]

Are there any industrial products distributors in Anchorage?

 

[mrb]

theres grainger in Anchorage. they sell that same hdpe tubing, $90something for 100ft

 

[nate379]

I'll have to give them a call.