overhead crane beam

[amine1340]

Hello,
During my inspection for an overhead crane , I found that the beam is welded on the lateral side (see attached photos ) when I check the drawing there was no details of these welds .
my question is :
Is the beam suppose to be welded like that or Is it supposed to be formed completely as one-
Thanks in advance
[img [URL unfurl="true"]https://res.cloudinary.com/engineering-com/image/upload/v1590253846/tips/received_287272985736259_psvbpi.jpg[/URL]

 

[Ganesh Persaud]

A cheap check you can do is a MPI, Magnetic Particle Inspection to check weld continuity. There are instances where you are allowed to join beams, these could be joined by splicing beams with a stiffened plate to the web and flanges or bolts. With respect to the welds not being on the drawing, then I would suggest that the contractor is trying to cut cost and may have just done a welded connection to the beams. You should ask for a certificate showing that there is no difference in normal stress of the weld and beam.

 

[FLCraneBuilder]

Why would you think its NOT supposed to be welded this way?

 

[kingnero]

^^^ this, all large overhead cranes have butt welded splices. There should be a construction file (or weld data book, whatever it's called) that has the details of the production of the crane, with MTR's, welding procedures, certifications of the welders, non-destructive testing reports, ...). At least that's required according to EU standards.

EDIT: for butt welds, UT (if the thickness is somewhere around 8mm or bigger) or RT is recommended. MPI (= surface crack detection) will not give much information about the structural soundness unless you remove all paint, and make sure you do not close any cracks by too aggressive sandblasting. It still won't tell you of the weld is internally free of LOF or other defects. If you are going to remove the paint, you should as well go all the way and have the weld UT'd.

 

[Lomarandil]

A butt weld like this may not have been part of the crane beam design, per se, but required by the fabrication shop to make up the total length required -- just depending on their ability to handle large pieces.

----
just call me Lo.

 

[JLNJ]

Does the weld look a little concave or is it just the angle of the photo?

 

[kingnero]

I was convinced the weld was convex, until I tried to see where it was concave. Now all I can see is a concave weld, no convexity... It's like a visual illusion!

 

[JStephen]

I would think the drawings would indicate if and how the beam was to be spliced- maybe not called out specifically where the splice is, though- but check notes and details thoroughly.
Also, depending on where the steel came from and where the site or shop is, there may not have been a choice- you can buy beams and plate maybe 60' or 80' long, but anything longer is not going to be made as one piece, and there may be additional mill limitations or hauling limitations involved.

 

[r13]

Double check the assembly drawing, or shop drawing. For such a long girder, splice seems unavoidable.