Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here


Caustic cleaning

Caustic cleaning

Caustic cleaning

We have had some cracking issues (SCC) after we've cleaned our 316SS heat exchanger in the past.  We are looking at cleaning it next week as it is fouled.  Does anyone have any suggestions on caustic to use or not use with 316SS??    

RE: Caustic cleaning

Do you have any idea if your cracking was from chlorides or caustic?
I doubt that it was caustic cracking unless these units were poorly washed and then run very hot.
My hunch is that it is trace levels of chlorides that are causing the problems.  Watch out for chlorides in all of the solutions that you use.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

RE: Caustic cleaning

Use a commercial prep with a heavy rinse agent component.  


Thomas J. Walz
Carbide Processors, Inc.

Good engineering starts with a Grainger Catalog.    

RE: Caustic cleaning

tomwalz is on the right track about using a commercial caustic product as they contain all the others need to make and effective caustic cleaner. On thing additional I would check on is the Cl content of any cleaner used as some carry high levels of Cl, comes from the NaOH used.

Could you give a little more information about your process as there are somethings you can do to greatly enhance the cleaning ability of caustic cleaners?

Also there are acidic cleaners that work on some soils and are quite safe on SS.  

RE: Caustic cleaning

And check the Cl level on your rinse water.  I am a big fan of less than 2ppm.

= = = = = = = = = = = = = = = = = = = =
Plymouth Tube

RE: Caustic cleaning


I'm a charter member of that club.  

RE: Caustic cleaning

Depending on the pH of the caustic you can tolerate a lot of chlorides.  I think I have attached a graph that showing results of chloride limits to prevent ClSCC in caustic.   Depending on concentration of caustic and temperatures you can get caustic SCC.   I agree with others that you also have to watch for chlorides in the rinse waters.  A failure characterization would be most helpful in determining if the problem is caustic or chlorides

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close