×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Contact US

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!

*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

What is happening here?

What is happening here?

What is happening here?

(OP)
This is a one month old sewage screening device. It is in an enclosed rated area and it's not pleasant, but not as nasty as most headworks. I have used 304 with 316 fasteners for years for this application for years and never saw anything like this. There was no welding done during or after erection.
Steve

RE: What is happening here?

Looks like iron contamination (rusting) and crevice corrosion at bolting.

RE: What is happening here?

Was this part fabricated in a shop with other metals i.e. steel being fabricated?
This looks like stray iron contamination.
B.E.

You are judged not by what you know, but by what you can do.

RE: What is happening here?

Maybe just surface stains. How were the surfaces cleaned before the photos were taken?

RE: What is happening here?

(OP)
I am pretty sure it is shop contamination. The device erection/start-up was supervised by the shop head man and in passing I remember him saying that a lot of new workers had just been added. And, for a normally slow to respond company, they are sending a couple of guys to do on-site pickling/passivation next week (I’m in PA they in FL).
Thanks
Steve

RE: What is happening here?

Fe contamination.
#3 looks like weld splatter from nearby steel welding
#4 looks like someone used a brush or wheel that had been used on steel.
and so on

What concerns me are the bolts. Will they remove the bolts, clean, and then install new hardware (that has been passivated)?
If they pickle with bolts in place they will only get acid into the joints, and they may cause serious corrosion damage.
This could be true of all mechanical joints. Getting them clean in one thing, properly rinsed can be another issue.

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

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! Already a Member? Login



News


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