W-Shape Edge "Condition"
W-Shape Edge "Condition"
(OP)
Just had an email come in from a fabricator showing what they called an "edge condition" on some W12x35's. I've never seen anything like this, so I'm curious if others have. Any idea what causes it? And, more importantly, any long term adverse effects (increased susceptibility to rusting, hot dipping won't work on affected areas, decreased strength locally, indication of bad steel all around, etc.)?






RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
Does the cracking resemble a shearing or splitting of the steel (say from cutting with a press or thermal shrinkage)? I cannot say i have dealt with something like that on my projects to date. but i would not think that it would effect your capacity in the beam unless it is some sort of indicators of bad steel as you mentioned.
RE: W-Shape Edge "Condition"
Take a good look through the spec (ASTM A6 for A36, not sure what it is for A992) and see if there is anything relating to this.
On A36/A6 plate, you're actually allowed to weld a spot up and then grind smooth as part of the mill work- called plate conditioning, I think. There may be similar provisions for structural.
It looks like you could just grind those spots smooth and be okay, assuming the grinding doesn't reveal other laminations or inclusions.
If there's going to be any dispute about acceptance, backcharging, etc. make sure that gets settled before they start grinding away the evidence.
RE: W-Shape Edge "Condition"
JStephen, thanks for that info. I'm having the fabricator show us on the part drawing where the "condition" is. Their original email just said "Hey, we're seeing this, but no one thinks it's a big deal." If it's not near a high moment demand area, I think we'll recommend that they just grind it smooth.
RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
Jstephen pretty well hit the nail on the head. That’s an inclusion or a lamination rolled out to the edge of the flg., or they didn’t have quite a big enough bloom/ingot/end of casting to roll the full section. You could/should have a testing lab do a UT scan through the thickness of the flg. tip in that region to see how far/deep (width) into the flg. width the anomaly goes. If shallow, grind it out, arc gouge it out, and weld it up and you are good to go. If it is very deep into the flg. it might be reasonable to reject it, and let the fabricator and his supplier fight it out. The mill will argue that the imperfection is in the same orientation as the primary stresses, so it is no big deal. You might just get by with grinding it out, to clean it up, losing 1% of the flg. tip area to no great avail. This would not be an insignificant defect if the flg. tip was loaded through its thickness.
RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
RE: W-Shape Edge "Condition"
At any rate, thanks again for your help!