LS6 Tommy
Well-known member
You 're absolutely right. I'm used to pneumatic control systems and pharma installations where just about EVERY system has a refrigerated dehydrator and numerous blow down legs.
Tommy
Galvanized or black pipe?
- Thread starter Ross/Kzoo
- Start date
You 're absolutely right. I'm used to pneumatic control systems and pharma installations where just about EVERY system has a refrigerated dehydrator and numerous blow down legs.
Tommy
akdiesel
Well-known member
Our local code for natural gas install says to use black pipe due the possibility of particles flaking off and clogging fuel gas nozzles and or other items. So they say to not use it for gas. Compressed air is a gas and can have more liquid than natural gas in the flow stream.
As for stainless. I have .035 x 3/4" for my air line and .049 x 1/2" for my pressure washer line to the other side of the shop. I like stainless and a 20' stick of .049 x 1/2" cost me around $50. Not to far off from copper.
The fittings are what can be expensive but shopping around ebay got me what I needed.
A six foot stick of 20mm 316 SS is $168 at Zoro. A 10 foot stick of 3/4 galv is less than 20 bucks. Black pipe is a couple of bucks cheaper.
Seriously- in what universe will this ever be "worth it"?
As for stainless. I have .035 x 3/4" for my air line and .049 x 1/2" for my pressure washer line to the other side of the shop. I like stainless and a 20' stick of .049 x 1/2" cost me around $50. Not to far off from copper.
The fittings are what can be expensive but shopping around ebay got me what I needed.
I saw 400 psi pvc used in airplane hangers in Florida. I live in East Tennessee and gave it a try in my new shop. A 20' length was $6.00. Got all my 400 psi fittings from Zoro. It was fast, clean, and in 2 years, I haven't had any issues. Just my two cents worth. I had black pipe up north for years and rust was a problem after a few years.
lakeroadster
Well-known member
Welcome first time posting person on a pvc air line thread.
show us some photo's of the installation and of the line marking on the pipe itself. Photo's make it real
Cyberbear
Well-known member
There is more than just a difference in price between US made and over seas pipe. I've been told by my plumbing supplier that domestic pipe is made from better quality steel and is why it lasts longer. I was disappointed when I used a left over length of black pipe from a natural gas job, and saw the large amount of rust that migrated to my air filters with clear observation bowls, which needed to be cleaned from time to time. Even though I live in an arid portion of Kalifornia, I still experienced a fair amount of rust causing moisture in my system and is why I now always use galvanized pipe as the most economical option.
rburke65
Well-known member
Wow......someone just tramped into a big pile......
lakeroadster
Well-known member
One thing that will help is if you order the pipe to an ASTM / ASME specification, and require it to be marked in accordance with that specification. Ask for Material Test Reports and state on the purchase order the material will be rejected if not in compliance with the purchase order specifications.
Then inspect it when it arrives, and reject it if it isn't correct.
This does 2 things:
- Ensures you get what you asked for,
- Prevents the vendor / supplier from selling you the rejects that others won't take.
LS6 Tommy
Well-known member
fsae0607
Well-known member
Mine is mixed. I have a filter/separator before the regulator on each of my drops. Not one problem.
Poor guy is new..doesnt even know what hes in for lol
He SHOULD know what he's in for . . . IF . . . he can Read and do a Search.
OP at least knows to use a STRONG, proven and safe material for airline system. Best systems for home garages are going to be black pipe steel or copper.
PatStroud
Well-known member
Black pipe in my fleet shop for over 40 years without a problem.
BMWED
Well-known member
I just run 1/2" hose and zip tie it to the rafters. Anything wrong with that?
OccupantRJ
Well-known member
JerryB
Well-known member
Well that certainly solves any potential for rust or galvanize flaking. I don't know why others here didn't think of this wonderful solution!
Jerry
I may be a new guy on this forum but I'm an old timer (40+ years in the business). I figured if the aviation repair shops in Florida used 400 PSI PVC in their regulated, inspected, and FAA approved facility, it was good enough for me. There is a hot rod shop in town that uses it too, and they build custom cars. But what do I know? Everyone is entitled to their opinion and this one's mine. Any of you nay sayers are welcome to "inspect" my shop any time.
Stuart in MN
Well-known member
I don't know what 400psi PVC is (PVC pipe pressure rating depends on temperature and pipe size, and it is typically sold as schedule 20, schedule 40 or schedule 80) but in any case PVC pipe is not rated for use with compressed gases. The problem is its ductility - if a black iron pipe in a compressed air system is damaged, it just cracks and lets the air out. If PVC pipe in a compressed air system is damaged, it tends to shatter and the rapidly expanding air can throw shrapnel all over the place, including into any people who may happen to be standing nearby.
It's a sore point with many of us here since it's a safety hazard, and since the pvc pipe manufacturers specifically state their product is not meant for use with compressed air. It's also an OSHA violation, even if many commercial shops use it and get away with it.
Some of us have personally witnessed PVC systems fail, so we know what it can do. In my case, no people were injured but there were shards of PVC stuck in the walls.
It's a sore point with many of us here since it's a safety hazard, and since the pvc pipe manufacturers specifically state their product is not meant for use with compressed air. It's also an OSHA violation, even if many commercial shops use it and get away with it.
Some of us have personally witnessed PVC systems fail, so we know what it can do. In my case, no people were injured but there were shards of PVC stuck in the walls.
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engineer2
Well-known member
LS6 Tommy
Well-known member
Not being a ball buster, but the FAA is not OSHA. It's also not just an opinion that PVC is unsafe and 100% illegal for any compressed gas ANYWHERE in the USA.
Welcome aboard, BTW...
Tommy
JerryB
Well-known member
First, the FAA is not in anyway responsible for workshop or worker safety. They do have lots of recommended practices, but these mostly address the issue of an aircraft being taken apart and put back together again. They do have the same kind of oversight for things like being able to safely work on an aircraft, but those practices are generally written to ensure the safety of the aircraft and subsequent users of that aircraft.
In the U. S., and every state I am aware of, the Occupational Safety & Health Administration (OSHA) is responsible for shop and worker safety. Federal OSHA standards and the OSHA Standards in every state I am aware of prohibit the use of PVC for air piping.
If you would like to see an OSHA enforcement action in Florida, take a look at this link:
https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=NEWS_RELEASES&p_id=21567
This violation cost the offending company $109,000 in fines, and no telling how much in insurance settlements for the injured employee, along with redoing the plumbing that was in violation.
Your shop is your shop, and most of us would never try to tell you what you can or can't do.
My problem with posts like yours is that you try to use totally invalid information (the so-called 'approval' by the FAA) to justify doing something that is really not safe, in response to folks seeking information.
BTW, the pressure rating of PVC is not the issue: The fact that PVC shatters in a way that puts people nearby at serious risk is the problem. That breakage can be on a 400psi rated (if there is such a thing) by just being struck by a hammer, something falling against it, or running into it. Please read some reports of PVC failures.
Jerry
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engineer2
Well-known member
The other issue is chemical compatibility. Some oils can weaken PVC over time.
texasprd
Well-known member
I used copper in my garage - brazed.