Air line sizing

[mb190sl]

I ran across this web site with lots of good technical information. One section I came across has a chart for calculation pressure loss for compressed air piping. There are lots of other links with information on just about anything.

http://www.engineeringtoolbox.com/compressed-air-pressure-loss-d_1014.html

 

[rockwithjason]

For the home guy you really can't go wrong with 1/2 galvanized pipe.

 

[AZAV8]

For the home guy you really can't go wrong with 1/2 galvanized pipe.

Jason,
I'm sorry, but you CAN go wrong with galvanized pipe. Over time, the water condensed during the air compression will rust the inside of the galvanized pipe. Also where the threads are cut on the pipe, the galvanizing will be cut off and the joints will rust as well. The best pipe for compressed air systems is copper. Copper is the only piping material I specify for compressed air systems I design for my clients. And the copper will be cheaper to install than the galvanized steel. It will also take less time as you won't have to cut all those threaded joints.

Where you live in Las Vegas, you won't get as much moisture in your compressed air system because of the low humidity in Las Vegas, but you will still get some. Other places like Illinois will have much more water in their compressed air systems because of their higher humidity.

Also, DO NOT use pvc or any plastic pipe for compressed air piping!!! The pvc or any plastic pipe WILL fail without warning and you will have sharp shards of pipe flying around that WILL seriously injure someone. It is not a matter of IF you will have a failure, it is a matter of WHEN.

NEVER, NEVER, NEVER use any plastic pipe of any kind for compressed gas service. PERIOD!!!

I speak from 30 years of piping experience. I have seen many, many failures of plastic pipe used for compressed gas service.

And that's my nickle's worth.

Phil

 

[kartracer55]

Jason,
I'm sorry, but you CAN go wrong with galvanized pipe. Over time, the water condensed during the air compression will rust the inside of the galvanized pipe. Also where the threads are cut on the pipe, the galvanizing will be cut off and the joints will rust as well. The best pipe for compressed air systems is copper. Copper is the only piping material I specify for compressed air systems I design for my clients. And the copper will be cheaper to install than the galvanized steel. It will also take less time as you won't have to cut all those threaded joints.

Where you live in Las Vegas, you won't get as much moisture in your compressed air system because of the low humidity in Las Vegas, but you will still get some. Other places like Illinois will have much more water in their compressed air systems because of their higher humidity.

Also, DO NOT use pvc or any plastic pipe for compressed air piping!!! The pvc or any plastic pipe WILL fail without warning and you will have sharp shards of pipe flying around that WILL seriously injure someone. It is not a matter of IF you will have a failure, it is a matter of WHEN.

NEVER, NEVER, NEVER use any plastic pipe of any kind for compressed gas service. PERIOD!!!

I speak from 30 years of piping experience. I have seen many, many failures of plastic pipe used for compressed gas service.

And that's my nickle's worth.

Phil

WHERE THE HELL HAVE YOU BEEN THE PAST YEAR?!!?!?!?! We could have used your help!! lol

Welcome to the board!

Jim

 

[bmwpower]

Also, galvanized metal will flake and come off inside the pipe, eventually clogging your tools

 

[Lu47Dan]

Copper is fine , but watch those pressures ! I have seen copper burst . I other words shut off the supply valve at night . Dan

 

[W-Cummins]

Also, galvanized metal will flake and come off inside the pipe, eventually clogging your tools

total bull #%^$ I suppose you have a tool that this has happened to??

 

[Charles (in GA)]

NEVER, NEVER, NEVER use any plastic pipe of any kind for compressed gas service. PERIOD!!!

I speak from 30 years of piping experience. I have seen many, many failures of plastic pipe used for compressed gas service.

And Never, Ever, make flat a$$ed statements.............. always qualify them!

There are two or three different types of "plastic" piping that are specifically approved for compressed gas service and meet the requirements of California OSHA specs, and are accepted by the US OSHA for such use.

I previously noted this in a thread that Luke had made "sticky" about the dangers of PVC, but this thread has disappeared with the change over to the new software.. Indeed, virtually all plastic pipe and certainly all commonly available pvc and plastic plumbing is dangerous and should not be used, but to state that "plastic" pipe should never be used.............. There are exceptions, problem is, they might cost more than copper.

http://www.nibco.com/nib-literature/public/DownloadFile.do?file=ChmairTech.pdf

http://www.pep-plastic.com/manufact...ropylenePiping/compressedairPipingSystem.html

http://news.thomasnet.com/IMT/archives/2001/04/a_dynamic_duo_t.html

http://www.penaplas.com/capiping.htm

Charles

 

[bmwpower]

total bull #%^$ I suppose you have a tool that this has happened to??

No. I don't own any pipe, but I have heard it multple times on here and elsewhere.

Let me guess.... you have galvanized pipe? I know it sounds crazy, but I have seen galvanized coating come off of galvanized metal before.

 

[gmasterman]

I work at a research facility that has perhaps 1000 feet of galvanized air piping. We are constantly having instrument problems with zinc and rust flaking off the inside of the pipe and ending up in orrifices in our instrumentation. Over time, a quarter of the screwed joints have devenoped leaks. Teflon was used as sealer. Every joint I break and go back with I use Loctite (645) hydraulic line sealer. In our facility, screwed galvanized piping *****! If I had the time and money, I'd replace it all with copper or stainless tube

 

[kartracer55]

total bull #%^$ I suppose you have a tool that this has happened to??

No, I havent, but the house uses galvanized pipe for gas lines and in some places you can see this happeneing. I believe all of the gas line was replaced when they kitchen was redone/added on to making it <15 years old, and this is in a basement with a dehumidifier. Now how fast do you think moist air will make this happen?

Jim

 

[gmasterman]

Around here Code requires that gas lines be black iron pipe because of the possibility of the zinc flaking off inside