×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

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

Jobs

Suitability of Stainless Steel in Potash Mine

Suitability of Stainless Steel in Potash Mine

Suitability of Stainless Steel in Potash Mine

(OP)
Currently I am working on a job that requires the use of 316 stainless support brackets in a potash mine (exposure to water, high humidity, potassium chloride, sodium chloride, and magnesium chloride)

The brackets are of a critical nature, basically if they fail the mine will be shut down for an extended period and I have been told there is no inspection schedule for these brackets.

Client would like a 40 year life.

Any thoughts, I am an electrical guy and from my internet searches SS316 should be good but would it last 40 years?

Thanks

RE: Suitability of Stainless Steel in Potash Mine

We use stainless steel all the time or HDG (the latter even for rebar).

Bigger problem with potash anchors is that the material is somewhat plastic and creeps or flows...

Dik

RE: Suitability of Stainless Steel in Potash Mine

I would suggest that you consider using 2205.  316 is not that corrosion resistant and this will be a low pH high chloride environment.

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

RE: Suitability of Stainless Steel in Potash Mine

Chance of getting chloride concentration on 316 with zero maintenance such critical pit over a long time- 100%

RE: Suitability of Stainless Steel in Potash Mine

Hanksmith,  If any doubts can you not use plastic brackets??
Watch out for dissimilar metal corrosion if the brackets support or contact any other metal.   (Are you at Boulby ?)
Corrosionman.

RE: Suitability of Stainless Steel in Potash Mine

(OP)
Ok, I have been in talks with a materials guy at our company and he does not seem to think there is an issue with using 316.

First - He mentioned that since the shaft is a constant temperature the humidity will be non-condensating and therefore any of the chlorides will be in dry salt form and dry chloride salts do not attack stainless.

Second - the water that these brackets come in contact with is potable water used to wash the salts off these brackets.

???any comments??? Would anyone still be concerned with using ss316?

 

RE: Suitability of Stainless Steel in Potash Mine

I see it as a case where for about the same cost you could put in a much more robust alloy.
The salts will be hygroscopic (want to absorb moisture) and dry salt on the surface will not be truly dry.
For long term use I wouldn't risk it.  Use 2205.

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

RE: Suitability of Stainless Steel in Potash Mine

I spec 2205 for high strength anchor rods and 316L for the remainder.  There is generally sufficient maintenance that these are not forgotten...

The larger concerns I have are related to the 'creep' of the salt body.

Dik

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!


Resources