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Could you please tell me which type of metal pipe is stronger, stainless or galvanized steel? Which is safer for high-pressure applications?

*Edited by Pete Zaria*.

Edited your post for capitalization, grammar, and spelling, and moved it to the Construction Materials section from the Pneumatic Discussion.

At 122 posts, I think you can figure out how to phrase questions better than "which pipe is more stronger", and post in the right section.

Additionally, this question has been asked before, and you could find your answer by either browsing the forum a bit, using the Search tool, or Google.

Spoon feeding time:
Using the Search tool, I searched for threads containing both words "galvanized" and "stainless". Turned up these:
http://www.spudfiles.com/forums/whats-s ... t6264.html
http://www.spudfiles.com/forums/galvini ... t9708.html
http://www.spudfiles.com/forums/iron-pipe-t8509.html
http://www.spudfiles.com/forums/steel-pipe-t5192.html

There are more.

I'm sorry to b!tch at you and rant, but I expect members with more than 100 posts to not waste moderator's time, and act maturely on our forums.

Peace,
Pete Zaria.

Pete Zaria wrote:Edited your post for capitalization, grammar, and spelling, and moved it to the Construction Materials section from the Pneumatic Discussion.

At 122 posts, I think you can figure out how to phrase questions better than "which pipe is more stronger", and post in the right section.

Peace,
Pete Zaria.

Post count and IQ aren't even remotely related. I've seen smart "noobs" and stupid "seniors."


Aren't both stainless and galvanized steel the same thing, but one has a different coating than the other. Anti-rust sort of thing.

Any stainless steel pipe you can get would probably be manufactured with
higher standards than common galvanized steel, just because it is normally used in environments where high strength and corrosion resistance are necessary.

In short, I don't know how the alloys compare in terms of strength, but a comparable piece of stainless will probably be stronger.

Edit@ modder: Actually, galvanized steel is coated with zinc, but stainless steel is an alloy with chromium in it, hence it does not rust where cuts are made.

Some stainless steel fittings are rated for 150psi, some are rated for over 10 000psi.
Hardware store galvanised fittings are rated for 150psi, galvanised steel fittings on McMaster are generally rated for 3000psi.
In terms of the strength of the materials themselves, type 316 and type 304 stainless steel (the most common material for SS pipe and fittings), both have a yield strength of about 20 000psi, while the weakest types of steel have a yield strength of about 30 000psi, which would seem to indicate that a given thickness of seamless steel pipe will be stronger than the same thickness of seamless SS pipe.

Welded pipe complicates this even further, and, frankly, your question is too vague to have a definite answer.

In conclusion, hardware store galvanised fittings rated for 150psi are weaker than stainless steel fittings rated for 3000psi, which are weaker than forged steel fittings rated for 6000psi, which are, in turn, weaker than SS fittings rated for 10 400 psi. So, for high pressure applications, I believe that you should use whatever material you want, so long as its pressure rating is higher than your intended operating pressure (these pressure ratings are really useful when attempting to find out what pipe will hold a higher pressure)

i was just curious do you think a 5in piece of 3/4in steel bought from homedepot will hold 200psi? thanks

jon_89 wrote:i was just curious do you think a 5in piece of 3/4in steel bought from homedepot will hold 200psi? thanks

short answere: yeah it will

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jon_89 wrote:i was just curious do you think a 5in piece of 3/4in steel bought from homedepot will hold 200psi? thanks

200 psi in 3/4" steel, your going to BLOW UP!
/sarcasm.

I have heard of people running unregulated co2(800+psi) into steel pipe with no fail, but I wouldn't recommend it.

1/2" Sch 80 PVC is rated to 900 psi, so you could run unregulated CO2 in that, right? It bursts at three times the rated pressure!

I find it funny that everyone says the pipes burst at three times the rated pressure, but only run them at 100 psi, even if they're rated for 600. It's slightly contradictory, no? Of course, you could just use non pressure rated material.... Know telling when that's going to fail, all the more fun!

But c02 is cold so it could make the pipe really brittle and fail, so no. You can try it if you'd like but I wouldn't.

Its only cold if you let it/

Oh and at my work I found a piece of galvanized pipe, guess the size?
It was over 2 foot in diameter and I could crawl in it.
It was massive, but I also found some scrap 2.5" SCH 40 pvc that I asked to take home.
I also have aluminum pipe 1" in diameter that is used for signs.Think it would be safe for pressure? and a few hundred feet of 4" sch 40 steel ha, but I can't get that a freebee

frankrede wrote: Oh and at my work I found a piece of galvanized pipe, guess the size?
It was over 2 foot in diameter and I could crawl in it.

well, you could become the first person launched out of a spudgun, lol

Just test the aluminum. I found some aluminum pipe (bike pump tube thing) and one end screws into 1" NPT. I plan on using a compression fitting or something on the other end, then pumping it to 200 psi. If it holds, then I'll use it regularly at around 100.