Welding Carbon Steel Caustic Piping
Welding Carbon Steel Caustic Piping
(OP)
Hello,
Is SMAW an acceptable welding process for caustic piping? Will the slag on the ID affect the corrosion resistance of carbon steel in caustic service or will the effect be negligible?
Thanks in advance.
Is SMAW an acceptable welding process for caustic piping? Will the slag on the ID affect the corrosion resistance of carbon steel in caustic service or will the effect be negligible?
Thanks in advance.





RE: Welding Carbon Steel Caustic Piping
What you really mean is the SMAW process permitted for joining carbon steel piping exposed to caustic solution?
Yes.
As a side note, I would verify the caustic concentration to decide if post weld heat treatment is required.
RE: Welding Carbon Steel Caustic Piping
If your caustic concentration is ~73% or greater, a generous corrosion allowance for carbon steel is a good idea.
More information from the Chlorine Institute....
http://www.dow.com/causticsoda/safety/piping.htm
RE: Welding Carbon Steel Caustic Piping
Yes, we will have 50% caustic solution with a limit on our design temperature to allow for the use of carbon steel. All our lines will be PWHT'd as well.