Chromatography Forum

I have a couple of Brass and a couple of SS valves and I need to use 4. Can I use the SS ones with the copper tubing or will the ferrules damage the tubing? If so could I just use some brass ferrules with the SS valves?

Best bet is brass ferrules on copper tubing and SS ferrules on SS tubing. Can you use copper tubing into a SS fitting? It seems to me that some of the gas regulators I've used have SS bodies and I've plumbed from them to the back of the GC with copper. You run the risk of galvanic corriosion over time, but you can do it. (Or perhaps the better way to state it: I've done it and not observed any failures.)

Echoing what Don says; the rule to follow is that the ferrules have to be harder than the tube, and the fitting has to be tougher than the ferrule - so you can use SS or brass ferrules in SS fittings on copper pipe, and brass in brass on copper, but not brass on stainless tube.

Using stainless where you could use brass is an expensive indulgence.

Peter

It's definitely more costly, but I don't have use for those valves at the moment with SS so I will just use them right now.