Compressed air lines in garage

gordon · Nov 21, 2004

Some food for thought when considering plastic pipe for air.

Water you can be under pressure but can't be compressed. So if you have a pipe failure someone gets wet.
Air is a gas and can be compressed, thus if there is a failure it's of the explosive pipe bomb nature---someone can get killed!!!!

If you had ever saw the aftermath of a pvc pipe explosion you would never even consider this around you and your family.

Yes there are a ton of people that use pvc for air without trouble, some even after my warning them about the pontenial hazard.

Use black pipe or copper!!! If your local plumbing or mechanical inspector ever saw a pvc install for air it would be red tagged out of service!!!

Gordon

Jeff396 · Nov 21, 2004

What I did in my garages, which weren't all that much larger than normal, was to make a run down the side wall and double back on itself which gave me 44' right there before I started making my drops. I'm not sure if it was really necessary but I figured every little bit helped especially when you start trying to filter air for painting. It's probably not a big deal for using the air for any thing else though.

Jeff

mark777 · Nov 21, 2004

DonS,

I know PVC is so tempting, affordable and easy to install, but it really has the potential to fragment just from cold air changes from outside temperatures. And as mentioned from other posters...it is a illegal

My first shop (commercial), years ago, was 90% PVC

The second was black iron pipe, and after 6 years developed scaling and rust even with adequate water traps and draining the compressor daily. I dealt with the down time and replaced sections as needed.

My third shop was all copper.

And my last and current shop is all copper. "L" and "k" pipe is legal, will pass inspection and once installed you can forget about any problems in the future. The last installation I did was from a diagram available from "Sharpe Manufacturing Company Shop air piping layout" found by Google search. It is excellent and I followed it almost exactly (except I used copper) and it has been my shop setup to date. The only difference in my case was I had to slit vinyl tubing around the copper to isolate it from the mounting to an all steel building.

I use IR 80 gallon and Porter Cable 60 gallon vertical compressors plumbed together, but use the IR exclusively as the smaller one is for emergency back up and wired separately. This way I still have 140 gallon volume.

Good luck, Mark

CTyler · Nov 21, 2004

( Some food for thought when considering plastic pipe for air.

Water you can be under pressure but can't be compressed. So if you have a pipe failure someone gets wet.
Air is a gas and can be compressed, thus if there is a failure it's of the explosive pipe bomb nature---someone can get killed!!!!

If you had ever saw the aftermath of a pvc pipe explosion you would never even consider this around you and your family. )

I used to make noise makers for the fourth of July years ago out of 1/2 and 3/4 PVC pipe. I would fill them with Pyrodex or black powder. With out fail these would never shatter they would just split in the middle.

My previous garage I used galv pipe with a seperator.

Boondox · Nov 21, 2004

I'm assuming you would use the thicker copper pipe, but what about diameter? Did you use larger bore lines at all to increase the storage capacity of your compressor? I was thinking of 3/4 inch runs, stepped down for the fittings.

The thing I like about the copper idea is the ease of customizing to fit in my crazy garage. With threaded iron pipe I have to choose from pre-cut lengths or pay to have a pipe cut to length and threaded.

By the way, PVC is out as experience tells me it gets rather fragile at 30 below. One bump of a PVC line and I'd have repairs to make under wicked cold conditions. Not my idea of fun.

Thanks again! Pete

Henro · Nov 21, 2004

I'm assuming you would use the thicker copper pipe, but what about diameter? 

Pete...you are using the past tense to ask about the future! /forums/images/graemlins/blush.gif

I plan on running two lines, one a high volume which will be 3/4 inch copper and a low volume in case I want to do spray painting and such, which will be 1/2 inch. I did get started, but at present I am not there yet, so I have been using a rubber line tied in at the compressor...

For high cfm needs, the larger the pipe the better. Seems like over 3/4 inch copper pipe starts to get pretty expensive though...

edit: Ok, I guess you did not use the past tense...but you were thinking it..weren't you! Ha,ha...I was anyway...story of my life...always slower than I like to be... /forums/images/graemlins/blush.gif

gordon · Nov 21, 2004

Pete three main choices when it comes to copper. Type M copper with red lettering on the side has the thinnest walls. Type L with blue lettering on the side walls is thicker. Type K has green lettering on the side and it's the thickest.

Type m is rated for more than ample pressure, but to be on the safe side I would opt for L tubing and use drop eared ells at my stub downs.

My two cents
Gordon

gordon · Nov 21, 2004

( I used to make noise makers for the fourth of July years ago out of 1/2 and 3/4 PVC pipe. I would fill them with Pyrodex or black powder. With out fail these would never shatter they would just split in the middle.
)

Better you than me, here is a picture of what can happen.

As I stated in my first post pvc can be safe for years but all it takes is one time for a failure. It's even legal for us to test pvc drain piping with air instead of water. Yes I've done it because of freezing conditions and lack of water on the jobsite. Quick 15min test at 5psi.

This is off the Charlotte pipe web site

DO NOT USE CHARLOTTE PIPE
PRODUCTS FOR COMPRESSED AIR OR
GASES
Charlotte Pipe and Foundry Company products are not intended
to be used for distribution or storage of compressed air or
gases. Use of Charlotte Pipe products in inappropriate
applications could result in product failure, serious injury or
death

Gordon

dliston · Nov 22, 2004

I used 3/4" copper for mine. Put the compressor in the garage and ran the copper through the wall to the basement (in the ceiling) and then put a drop with a drain and a regulator/oiler/water separator. Use a short piece of hose to quick connect the compressor to the run down to the basement - that way I can still use the compressor for tires, etc. in the garage.

My basement shop isn't that big, so I just have a few rubber hoses that I quick-connect to use it. Works great except in the summer the air in the garage is so humid that I get quite a bit of water in the compressor and lines, but the drain and water separator take care of it. But I still have to drain the water from the compressor after each day's use.

Doug

DonS · Nov 22, 2004

If copper is used will the soldier ever crack on the joints at the outlets from pluging and unpluging the hose. I know it has to be clamped tight but there still will be some movement.