Two years ago I bought a 5.5 ton cast iron table, which was unloaded with surplus Steyr military crane. Crane operator used chains to lift the table and everything went fine. Later a friend bought even bigger (10 ton) table (to be used as a base of CNC machine). It was unloaded with the same crane, but this time operator decided to use belts made of some kind of fabric instead of chains. He managed to lift the table about 1 meter above the truck before belts snapped and table fell back on the truck. It is fascinating that truck was able to drive after table was removed, albeit there bed was visibly bent.
Another accident I’ve seen was a large steel bridge that locally buckled while being slid onto supports (it was welded from prefabricated parts on the shore). Later I was doing measurements inside that bridge during load test 
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Nothing says, “Serious about your tools” quite like a 5 or 10 ton table.
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I keep looking at that yellow thing at the back near the bottom and imagining two people on there. “Well this is the crappiest ride I’ve ever been on…”
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It’ll be a base for CNC milling machine with 3x2m work area. Right now I use it as a welding table and it’s a wonderful tool for that
By the way, if anyone has an idea how to safely move such thing into a building without removing roof, any advice would be greatly appreciated.
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Assuming you have enough door width, couldn’t you jack it up, put some of those house moving dollies under it, and push/pull with whatever trucks, loaders, etc., you have?
Edited to add: I’ve seen some pretty crazy stuff moved with those machine skates, if you’re on smooth finish floors. Crazy psi pressure on those little wheels, though, so figure out if the slab can take it first, I would think.
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Thanks! House moving dollies seem like a good idea and that’s the first time I’ve heard of them. Especially since the table now sits on unpaved ground in my garden.
I was originally a bit wary of machine skates, because I’m not sure if the floor will withstand the pressure, but thinking about it more, I’ve moved a 2.5 ton milling machine on the same floor with hydraulic pallet truck and nothing bad happened.
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Speaking of moving heavy shit, this semi-recent video from AvE is totally on brand:
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Also thinking about it a bit, if you have a place in your area that rents heavy equipment, the Gradall 544D10-55, e.g., is rated for 5 ton, and has tractor tires, so should be no fuss, again depending on your door width and whether you can pick it up on the long axis or not.
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Maybe an air sled? That’s how we always had safes and vault doors moved.
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Why was the TARDIS there? And how was it receiving a call!?
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I suspect that is some sort of tensegrity sculpture, but I can’t see all the wires.
Makes me wonder if the steel structure should be equipped with strain gauges so that it generates a warning before being put under excessive stress.
Unfortunately, the only available video doesn’t start until a few seconds into the disaster and we can’t see the beginning. This was a mandatory load test, and the last test before handing over the crane & ship to the customer.
During the load test the hook broke, probably due to a material fault. Under the sudden loss of load, the boom lurched upwards, amplified by the ship starting to roll, and the anti roll systems didn’t compensate fast enough. The cable-stayed boom then flipped over to the backside, where it was supported by nothing and collapsed.
12 people were injured, one of them remains in hospital. It’s a “miracle” that no one was killed - the yellow thing you see rushing upwards at the end of the video? That’s the by itself huge crane block attached to the hook, and it misses the operator’s cabin very narrowly, which was occupied with 5 people - they had to be rescued by the fire department’s because their ladders and walkways were destroyed.
To me this raises some questions not so much about the crane itself, but about the system of ship and crane, and its safe operating limits. Maybe it’s even good that this happened in the test, and not at sea.
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In a proper engineering company, the responsibility will be buried under enough process overhead and distribution of tasks that no one will have to fear for their career.
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A heavy crane does everything gently. You can design for a slow, careful lift. It is important to put the load down carefully, so it doesn’t sit on the ground all at once, and release all the tension in the cable. You can design for a slow, almost static load, but it is very hard to design for the case if something breaks, something drips, some cable suddenly got taught, or suddenly goes slack. So, if the hook breaks or the bottom drops out of the load they were trying to lift, then everything is going to hell in jig time, no matter how carefully the crane was designed.
Here we get the usual comments - “the Germans use cheap, bendy steel”, “this was the accountant’s fault for cutting costs”, “the engineers should be sacked”, “the engineers will be able to hide this in the paperwork”, “the crane should be designed to be safe at all times”…
Yeah, right, folks. Off you go, and tell Liebherr how to build cranes. I am sure they could be glad to learn from the real pros.
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