Stainless tubing vs copper?

[cappyjon431]

Yesterday my compressor (Bauer Mariner II) developed a pinhole leak in the 3/8 inch stainless steel tubing that goes into the oil and water separator. My third stage pressure will not go higher than 2800 psi with the leak, and it is slow to get there.

I am on a very remote island in the Caribbean. Bauer will not be able to ship me the bended stainless steel part until at least Tuesday (closed for a long holiday weekend). I am considering using copper tubing/fittings as a temporary solution. I did a little research online and 3/8 inch copper tubing has a bursting strength of 4800-5200 psi.

Normally I would just wait for the replacement part, but I have a group of 20 students scheduled to start their OW class on Monday and I need to fill tanks. Is using copper as a temporary fix a bad idea? Any other suggestions?

Thanks!

 

[Hallmac]

Short term you will be fine, I have used it several times. Keep the run as short as possible I have used it up to 4700 psi for months at a time without incident.

 

[DevonDiver]

It shouldn't be a problem. I've used it before, and seen plenty of operations here in Asia using copper.

 

[cappyjon431]

I was warned by one of the expats living here that the copper tubing available here is not up to the same standards as the copper tubing in the States so I nixed the idea.

I was able to find a local who did stainless steel welding and he was able to weld a patch over the pinhole and it appears to be working. I've filled about 20 tanks this morning with no issues. This is just a temporary fix, as I am going to order two of the sections from Bauer on Tuesday morning.

Thanks again for your advice!

 

[Zodiacdiverdave]

Good to hear you are up and running again but I just want to add a note for anyone that may find themselves in the same situation. Tubing comes in verying wall thicknesses thus the pressure ratings can very. Tubing has a max working pressure and a min. burst pressure. For pnuematics the burst pressure is 4 times the working pressure. Using a tube with a burst pressure of 4800-5200 would be risky. I would look around for something a little stronger then that and limit your output pressure on the compressor so you provide a good safety margine.
ZDD

 

[GKaplan]

Hi CappyJon431,

I'm not sure what type of copper you are referring to, but copper is generally not rated that high. Also, copper work hardens over time which makes it very brittle. I can't in good conscience recommend using this material, even as a temporary solution.

 

[Gilldiver]

There is also seamed and seamless tubing. Seamless will cost more and be rated higher then seamed.