Pitting corrosion on 316L SS problem
Pitting corrosion on 316L SS problem
(OP)
We have some problem with external pitting corrosion on 316L SS instrument tubing (it leak during in-service).
Can anyone advise me for How to prevent this problem or How to inspect it during in-service?
Thanks for any help...
Maty
Can anyone advise me for How to prevent this problem or How to inspect it during in-service?
Thanks for any help...
Maty





RE: Pitting corrosion on 316L SS problem
BP have tried chemical treatment as described in NACE Corrosion 2010, Paper 10305
Shell used UV-resistant thermoplastic sheathing as described in NACE Corrosion 2008, Paper 08254, but this was really for expediency.
Woodside require use of 317L that seems to have worked OK.
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: Pitting corrosion on 316L SS problem
You need to look at how the corrodants and moisture are getting to the tubes. Sometimes a good paint job is all that you need, but watch out for the fittings, especially the threads. You should leave them un-coated for maintenance and inspection purposes.
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Plymouth Tube
RE: Pitting corrosion on 316L SS problem
RE: Pitting corrosion on 316L SS problem
Aaron Tanzer
www.lehightesting.com
RE: Pitting corrosion on 316L SS problem
If the Mo is down near the 2% minimum, make sure to buy 317L with the Mo up near the max., 4%. If your 316L has close to 3% Mo, I'd look for a better stainless.
"You see, wire telegraph is like a very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? Radio operates the same way: You send signals here, they receive them there. The only difference is there is no cat." A. Einstein
RE: Pitting corrosion on 316L SS problem
If some of this ruing is in protected areas where it doesn't get washed by rain then you will need something better.
Without special heat-lot order 316 will be 2.0% Mo and 317 will be 3.0% Mo.
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Plymouth Tube
RE: Pitting corrosion on 316L SS problem