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Thought I would share this with everyone. This is one of two cracked welds on a 20k lb weldment. This weld is on one of the four lifting eyelets. Let this be a lesson to us all, never let a machine shop perform welding if they are not comfortable with performing the work. Because of these cracks, porosity, and undersized welds, four of these weldments are being repaired. This got me thinking, what other "mistakes" have you seen from vendors or employees on your end?

Jonathan
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Oddjob83
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can we get a "bigger picture"? some times things look horrible out of context, especially if the design was poor from the start.

But by the color of that weld looks like it was waay too hot too fast, maybe there wasn't any preheating. hard to say without seeing the whole thing.
jwmacawful
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you really can't tell too much from this picture. can you get a larger one showing more detail and perspective?
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I will get a better picture tomorrow, however due to my non-disclosure I cannot do the whole thing. We are pretty sure there was no or incorrect pre-heating as this is 6" plate welded to 6" plate.
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I have never trusted "Fab-shop" pad-eyes. Good on you for inspecting them. I always do.

I far prefer, for any load I'm responsible for, to weld the pick-points myself, so I can put them where they belong, rather than where the engineer's computer THINKS they should go, and then I know who welded them. If I have to be under the load for ANY reason, I prefer my own welds.

If you hadn't caught this, it could have cost lives.

Steve S
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How heavy was the pick?

Nevermind... 20K...

Can you say "what" it was?

Steve S
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I have never seen a cracked weld on a pad-eye. I have seen undersize/LOP/cold-lap/undercut, and insisted on re-working them before the pick.

Steve S
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To be technical this weld is not on the "eye" but the eye welded to this piece of plate. To be honest I was shocked that this was not picked up when it was inspected by the machine shop or my engineers. But I think if nothing else it has made us all more aware of the importance of quality inspection!
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So, how did you find it? Pre-lift inspection, after the rigging was in place?

Steve S
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Until I can get better pics here is what is looked like when we found it. As to what it is I think I can safely say it is a clamp for 30" pipe. It will be used to push pipe 5 miles through a tunnel in South America. If you know what a directional drill looks like it is something like that.
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I was not around when it was lifted off the truck ( I shouldn't admit that). I found it when we were looking it over in general.
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Thank God you found it before it went in the air to it's destination.

Steve S
jwmacawful
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Otto Nobedder wrote:I have never trusted "Fab-shop" pad-eyes. Good on you for inspecting them. I always do.

I far prefer, for any load I'm responsible for, to weld the pick-points myself, so I can put them where they belong, rather than where the engineer's computer THINKS they should go, and then I know who welded them. If I have to be under the load for ANY reason, I prefer my own welds.

If you hadn't caught this, it could have cost lives.

Steve S
i have worked on dozens of multi story high rises and never seen or heard of a pad or lifting eye cracking or failing. i would much rather trust one coming from a fab shop than a machine shop. it's my observation that every other guy in a fab shop is a skilled welder while most machine shops that i know of have one or two guys that specialize in it. all respect to both kinds of shops.
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Hey, welcome to our forum. I think we all have stories like that. When you see the quality delivered, its no wonder the prices are so cheap, then we fix it again.

Its hard when your vendor delivers things that obviously have had no inspection and you have to weld it in with 100% inspection and also some ndt as well.

Mick
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Awright... I re-read.

Coming off the truck was the greatest danger to people.

This appears to be a very heavy "line-bore" job, where the lug in question is responsible for pushing the pipe through soil. A fail is very expensive, but not generally life-threatening.

Steve S
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I've pulled pipe before, not sure of this exact job here.

When the rigging or anchors fail, you've got metric buttloads of stored energy tossing rigging everywhere. Very bad day if you're in the way. S/F...Ken M
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Here is a little better photo for you guys. I should have been clearer on what it was, this cracked weld serves two purposes. First it is a safety brace of sorts if it were to blow up and second it holds the block that the lifting eye is on. The bad thing about where it is, it will be lifted every time the machine is tore down so it needs to be good. Anyway this is all I have permission to say and show in the picture.
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With the dye-pen, that looks familiar.

I've seen that type of cracking on dual-shield, when the machine was going maxed out and the base metal was very cold (below 15*F).

With the size of those blocks, I'd think dual-shield would be the process of choice, and a pre-heat may be in order.

Then again, with the other problems you noted, choosing a different shop for the work may be in order...

Steve S
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BTW,

In reference to your original question, I'll have to spend some time this week to put together an album of all the cracked welds, as well as the corrosion stress cracking of stainless steel I've been dealing with frequently lately.

I believe I have quite a few of each, and while I didn't add comments to to the photos, I have enough "context" photos to remind me of the details of each.

Steve S
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Was talking to Steve and he requested a update on how this all turned out. Well we sent two units back to the vendor to be repaired and when done sent a guy up to do a final inspection before we shipped them back. When I got them back I was VERY disappointed to say the least when I found that there was another cracked weld that was missed by everyone else. You can't see very well in the picture but while I was inspecting one final time I saw a faint line through the middle of the weld through the paint. Upon wire wheeling the paint off you can just see a faint crack. What I did not know until I started to grind into the weld was the 6" plate has a 3/4" bevel on the weld side. Lets just say I went though a whole grinding wheel (or two) before I got to the end of the crack. Yes it cracked the whole way through. I thought for sure is might have just been the top weld, but nope it went all the way though the root. We have learned a valuable lesson form this project! We have 4 more of these weldments being made as we speak and we are either sending a welder to there facility or bringing the pieces here to do all the welding. Besides the welding their machining was spot on though. I am interested seeing anyone else's projects that went by the wayside. Surely I am not the only one this happened to.
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WOW!

That's a dramatic update!

(I have some more comments on this but they are strong in nature and I'll not make them publically)

It's a damn shame this shop does not appear to understand the critical nature of these welds.

Please share what you find as the ultimate solution.

Steve S
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You know what? I would refuse to rig that pick.

Knowing what I know, those idiots shoud NOT be welding pad-eyes on ductwork.

I'm sorry, but that's how I feel. With what you've shown me, these people shouldn't build stairs, much less lifting points.

The repeated failures should be a clue...

Stop this before someone is hurt. You can have a qualified welder weld the pad-eyes in the lay-down yard and be far safer than these half-ass welds you get from the fab-shop.

Steve S
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As far as the fix for the welds, what I did for the last repair is pre heat the material to 250* and began welding from the root up. I kept the interpass temps around 200-250 and welded it all as quickly as I could. The material cooled very quickly between passes. I also used a wire wheel on my grinder in between all passes (habit of mine). When I reached the correct weld size I did a final wire brush and covered with a welding blanket to slowly cool it off. I had absolutely no problems with this procedure. I am not saying this is the absolute "gospel" way to do it but it has worked for me. I found out later that they just welded it and went on to the next weld with no preheat or slow cool. Also not correct was the HUGE weaves they did instead of stacked beads to achieve the final weld size which for them was not up to the 3/4" it was supposed to be. I do not blame the machine shop for not doing it "correctly" because that is not their forte but rather wish they were more up front on what they can do and knowledge of welding. Also on the note of MIG welding, we use Lincoln L-59 exclusively on our heavy weldments in my shop and will say I absolutely love the quality we get from this wire. just going from L-59 to L-56 we all can tell an huge difference using the same welder settings.
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I suppose that's not fair, though...

Since I know more than a rigger would in this situation...
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To ease your mind these units were NOT lifted again until they were all inspected, again, and re welded where necessary.
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