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This ones going to leave a mark

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Ronsii

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Authorized Supplier...LOL that's a good one ;) even sounds official :) I just picked up a battery, brake fluid and some anti-freeze from an authorized supplier a few minutes ago.... still have to find a brake cable from a different authorized supplier... and after that I need to get on the computer and order some other odds and ends from even yet a different authorized supplier. :cool:
 
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wildpig1234

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Let the blame game begin....lol... Liebherr was quick to make statement trying to wash their hand. So did Ropeblock. I am sure ropeblock supplier will also issue a negative statement and and will just blame it on the workers that casted the hook? lol..
 
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.RC.

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Kiwi-truckwit said:
I saw somewhere else that the hook was made in Holland, so perhaps it's the same company.
There's a video floating around on Facebook of the lift from a different angle, starting from before the failure. It looks as though it was the boat listing over that caused the boom to go over the back, as opposed to the shock unloading.
Click to expand...

That would be right. I have worked on the docks as a lowly hook hookeruperer, and the ships always used their onboard cranes. They would list over quite a lot lifting 24 tonnes out in one go. On one job they had to get someone in the second crane and when the ship was slewing to over land, the other crane had to slew over water to stop the listing, otherwise the safety would just cut the crane power out.

So with the boom near vertical on a heavy load the ship would list, the hook snaps and the ship lists back and folds the boom over backwards.
 
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wildpig1234

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I wish they would have included more of the boom at the top of video and less of the water at the bottom...lol
 
Nige

Nige

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I bet in all the stability calculations for the ship no-one ever considered a load of that magnitude being instantaneously released in the way it was. Once the load came off everyone involved was simply along for the ride. Gravity, Isaac Netwon's famous invention was completely in charge.............
 
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terex herder

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They are very good land crane people. But they stepped out of their comfort zone and got a lesson. Brings to mind the old line "You can always tell a German, but you can't tell him much".
 
Natman

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A German? I've always heard that saying in referencing a Texan.....specifically a Texan ironworker!
 
DMiller

DMiller

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Regardless the superficial or visible damage, would serious doubt any structural integrity of the components above the pedestal mounts. That is going to take some splainin' and be a write off by most parties involved.
 
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Birken Vogt

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I don't know anything about the ocean or ships or their cranes, but it looks like when the hook parted, very little damage was done at first. It seems to me that the ship began to list over toward the dock, I am imagining because they had a lot of ballast over on that side to counterbalance the lift. And once the crane went over vertical is when everything started to come unglued.

Can someone confirm, if the ship had not listed so far, would it have all pretty much stayed together?
 
crane operator

crane operator

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Nige said:
I’d be interested to know how much load was on the hook when it failed. I’m assuming that the load should have come clear out of the water during the test lift.
Click to expand...

From the reports I have read. The plan was a 5,000 ton lift. The hook failed at around 2,500 tons. I'm sure the "barge" they are lifting does not come out of the water, its probably not that structurally sound. The water on the outside, helps hold the walls holding the water on the inside, as long as its in the water. They simply watch the tensionometer or pressure transducer readings to know when they are at capacity or the weight they want to test at.

There's really not counterweights per se on a crane like this. They simply flood water compartments on the one side of the ship as they are lifting on the other side. It has to be a really slow process on a max lift, filling compartments as you add weight with the crane.
 
DMiller

DMiller

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As far as the flip over, Kinetic Energy release and the effects of Force related Counterforce apply, those cables regardless how new were stretched, like rubber bands, the sudden parting allowed stored energy to release off lift cables as well boom support cables and being at a nearly vertical boom angle the energy had to go somewhere. The booms unhindered flipped up and then contacted the head block, lattice booms will transfer point of pivot to where ever they contact and then start a chain structure collapse. Really bad day for the guy in the seat, do not know if I could return to that chair to try this again.
 
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Nige

Nige

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crane operator said:
There's really not counterweights per se on a crane like this. They simply flood water compartments on the one side of the ship as they are lifting on the other side. It has to be a really slow process on a max lift, filling compartments as you add weight with the crane.
Click to expand...
And there lies the root cause of why it went over. There would’ve been no way to pump 2500 tons of water out of the ballast compartments to compensate for the loss of the load in a couple of seconds. Therefore the ship was always going to roll big style away from the load (that fella Newton again). With the test lift being performed at a fairly small radius it wouldn’t take much in the way of roll for the boom to go past the vertical position.

Anyone have any insight as to why this heavy lift ship was designed to lift over the side as opposed to most of the ones I’ve seen that were more like a pair of sheer legs over the bow or stern.? That setup is much more stable.
 
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Birken Vogt

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DMiller said:
As far as the flip over, Kinetic Energy release and the effects of Force related Counterforce apply, those cables regardless how new were stretched, like rubber bands, the sudden parting allowed stored energy to release off lift cables as well boom support cables and being at a nearly vertical boom angle the energy had to go somewhere. The booms unhindered flipped up and then contacted the head block, lattice booms will transfer point of pivot to where ever they contact and then start a chain structure collapse.
Click to expand...

But that isn't what I thought I saw in the video that shows the moment it parted. The block and cables and boom seemed to stay pretty much in their places at first, it was when the ship tilted back so the boom was beyond vertical that everything went sideways, literally. Here is a Youtube link of the above video.

 
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