Pickling and passivation of IN 625 tubing after bright annealing

[AnsAvi]

Does IN 625 tubing that has been bright annealed (reducing hydrogen atmosphere) need to be pickled and passivated? The tubing conforms to ASTM B444.
My assumption is that in the absence of any scale, the tubing should be able to self passivate pretty uniformly. Is that reasonable?

 

[EdStainless]

It should not need to be pickled, in fact if you give a short pickle there should be no change in appearance at all.
As for passivation, remember that this is a cleaning process specifically to remove free iron from the surface.
If the tube has been properly handled (never contacting steel) and it has not been polished there is no reason to passivate it.

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P.E. Metallurgy, Plymouth Tube

 

[AnsAvi]

Thanks as always EdStainless for your reply.