Stainless Steel 321

[boo1]

Does anyone have experience with 321 in the marine environment for tubing?

 

[Jason8zhu]

it is an austenitic stainless steel with yield point of 205MPa.note it is susceptible to SSC.

 

[EdStainless]

It does not have as good of corrosion resistance as 304, it is totally unsuited for use anywhere near a marine location.

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P.E. Metallurgy, Plymouth Tube

 

[boo1]

Contractor wants to substitute our 316 tubing with 321, because availability.

 

[Jason8zhu]

if u are their customer, feel free to reject this proposal since this steel is low in corrosion resistance.
if the contractor indists on use this steel, i think they need to prepare a corrosion assessment and detail design analysis on the material to Sulfide Stress Cracking and Hydrogen Induced Stress Cracking.

 

[dicer]

321 not good for marine apps? Years ago I remember machining a lot of it for a very specific marine application and it was for above and below water applications.
Very large company, so they must have known what they were doing, as they did thousands of tests on materials on a constant basis.

 

[Jason8zhu]

Hi, Dicer,
As far as my understanding, steel 321 is suspectible to Chloride and H2S corrosion. It thus not suitable using in seawater and oil gas structure within H2S. however, for the application in river and lake, i think it is OK.