×
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

Cracking in I-profile lifting beam

Cracking in I-profile lifting beam

Cracking in I-profile lifting beam

(OP)
Hi
We have a 3 ton (SWL) single girder lifting beam which is to be installed in a pump station.  Upon inspection of the coating of the beam it was noticed that the paint is lifting from area where the flange and web comes together.  It seemed as though delamination occured since one could pull small flakes off the beam.  We then had the beam shotblasted to clean all paint off and tested the areas of concern with magnetic particle testing and a crack showed up which seemed to run the length of the beam.  After grinding a certain area of the beam and performing magnetic particle testing again the crack still showed up.  

The supplier of the steel beam says it is part of the rolling process and that the structural integrity of the beam will not be compromised.

Has anyone seen this before and shed some light on the cause?  Is it anything to worry about?

I've uploaded a picture of the crack after magnetic particle testing.

The beam size is 457 x 191 x 74 kg/m and has a 8.1m span.

Thanks for the help...
 

RE: Cracking in I-profile lifting beam

To me, those appear to be defects that are cause for rejection.  Did your supplier provide something more descriptive than "it is part of the rolling process"?

RE: Cracking in I-profile lifting beam

Agree with TVP. The crack-like discontinuity at the far left edge of the photo appears to have some depth associated with it.

RE: Cracking in I-profile lifting beam

Regardless of the severity of the indication, the suppliers response was totally unacceptable.  Welding defects are not accepted 'as part of the welding process', nor are truck rollovers due to defective tires accepted 'as part of the tire-making process'.    

RE: Cracking in I-profile lifting beam

These are rejectable indications for this type of service.

RE: Cracking in I-profile lifting beam

(OP)
Thanks for all the replies.  We have rejected the beam but the supplier said that they have received an opinion from an independant metallurgist who says that the structural integrity of the beam is not compromised.  I'm still waiting for the report so I don't have any details yet as to why they say the beam is ok.
As soon as I've received the report I will let you know.
 

RE: Cracking in I-profile lifting beam

cvis;
Here is a tip, I would recommend you have this beam load tested by an outside entity as we do with our turbine lifting beams, and have it re-inspected after load testing, assuming the report from the 3rd party indicates acceptable for use.

RE: Cracking in I-profile lifting beam

Hi cvis

Your right to reject the beam, ask the supplier is he willing to guarantee its safe to use in writing.
I would also have the beam inspected by a third party after load testing.
How long have you had the beam? and did the metallurgist actually inspect the beam? I doubt he would write a report without at least seeing it.

desertfox

RE: Cracking in I-profile lifting beam

My insurance company would hang me out to dry if I used this in an overhead lifting application.
It may be suitable for an I beam but not for lifting equipment.
If you need to push the point then have a core drilled out and a metallographic cross section prepared.  
1. This is a crack-like indication and not suitable for load bearing applications
2. I'll wager that the remaining metal thickness in this area is below the minimum allowed for this size beam

= = = = = = = = = = = = = = = = = = = =
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!


Resources