Chloride Corrosion

I would go with Hastelloy C-276 or zeron 100 stainless...

http://www.capcis.com/casestudies/oilandgas/CRATestReport.pdf

Maybe also Incolloy?

Thank you all for your comments.

Because it is oxygen free and high pH, I wonder carbon steel, or 316 SS would be fine?

kevin,

A review of information available on the internet shows that 316L stainless steel is acceptable for use in systems up to 5000 mg/l PROVIDED that there are no deposits where chloride cells can form and attack the base metal. A high pH also helps considerably.

If the system can be made stagnant ( i.e. no flow) you may have problems.

If the pH is uncontrolled, you may have problems

Where deposits may accumulate, I would use the C-276 or Zeron materials, AL6XN and other super duplex materials may be suitable.

With metalic materials selection.......the answer, of course, is "it depends"

316ss might just be acceptable at lower temperatures, but yours are quite elevated. No need to resort to hastelloys, etc. But I would definitely go for a super duplex ss such as the aforementioned zeron 100, or SAF2205, SAF 2507, etc, etc. Alternatively there are some types of austenitic stainless steel, eg 254 SMO, specifically designed for handling chlorides.

It also depends on the type of equipment, and the level/type of corrosion that is acceptable. In some equipment crevice corrosion can be terminal, in others non-existent. Ditto for stress corrosion cracking, etc.

It can also depend on whether the material is cast or wrought.

"4700 ppm Cl", then what is the rest?

Say, if the rest is water, then Oxygen is threin:)

I recommen to use AISI 316 S3 and better than this CPVC O UPVC

is also used CS with liners PTFE

greeating

Ing Galindo, Alberto

EXCUSE ME ALL THE MATERIAL ARE AISI 318 S3, BUT IN THE INDUSTRY THEY PREFER TO USE CPVC O UPVC, IT IS CHEAP AND EASY TO MOUNT, WITH THE SS THEY HAVE A CERTAIN USEFUL LIFE AND THEY ARE EXPENSIVE
CS AND LINER DE PTFE IS BUILT IN SHORT PIPES AND IT IS EXPENSIVE

I SEND INFORMATION FOR SELECTION OF MATERIAL SS
AND CHARTS

"PETTING RESISTENCE EQUIVALENTE NUMBER (PRE)

http://www.atlassteels.com.au/site/pages/atlas-technical-notes.php#note2

PTFE would work too, as would graphite and glass.

Thanks a lot for your guys comments and suggestions, indeed.

As per NACE MR0175 Table A.24, Duplex stainless steel could used at 232C, at any combination of chloride concentration and pH, so Duplex should be okay.

Also, considered my case is oxygen free and high pH, I wonder carbon steel could be used as well.

Again, thanks for your comments and suggestions.

Non of the steel will be good. If you have chloride then at 100+oC one will form HCl vapor causing corrosion issue.

There are solution which allow you to use any steel you want that is coating with plastic. You can buy one side sticky plastic film using Teflon as material of choice. This will take your temperature conditions as well as will not corrode the metal

If you want more details let me know will guide you through