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Big crane safety fail today, a 60 ton crane snapped its boom

Never had boom failures when I was much younger. A bit more common now but we adjust. Hydraulics just need a bit more time to git er done.
 
I wonder if the crane computer was circumvented. The boom did not fail from a side load, just a straight hoisting load.

With this age of crane, I would not expect a failure such as this unless somebody had bypassed the safety devices or more likely, did not enter the correct parameters when the set the crane up for the lift.

Thankfully no one was hurt. These types of stories, usually don't end well.
 
I wonder if the crane computer was circumvented. The boom did not fail from a side load, just a straight hoisting load.

With this age of crane, I would not expect a failure such as this unless somebody had bypassed the safety devices or more likely, did not enter the correct parameters when the set the crane up for the lift.

Thankfully no one was hurt. These types of stories, usually don't end well.

I do not know much about crane safety, but I thought that modern cranes have load moment calculators, and warning and such devices. I wonder what happened. I will try to find out and post.
 
I do not know much about crane safety, but I thought that modern cranes have load moment calculators, and warning and such devices. I wonder what happened. I will try to find out and post.

Those things dont always save your life, shit happens when u least expect it. Hopefully no one was hurt.
 
I do not know much about crane safety, but I thought that modern cranes have load moment calculators, and warning and such devices. I wonder what happened. I will try to find out and post.

They do. That is I why I am wondering what lead to this failure.

The new boom designs are much lighter in weight but they have also decreased the safety factor between full load and destructive overload.

Things do happen but with the current technology in crane computers, it takes some effort to make a lift outside of the cranes safe operating envelope unless they were making a lift at the limit and encountered a significant wind gust in line with the boom and pushed the load away from the crane center point.
 
Used to work in the summers in the '60's on the "Test Pad" at a large Midwestern crane manufacturing plant -- it will remain nameless. As the name suggests the test pad was where the cranes were setup in a engineering-specified configuration with a certain counterweight, length of boom, cable size and hook block(s). Besides doing the assmebly the three of us on the pad applied and wired strain gages in various locations of interest to the engineers and wired them to readout (analogue in those days) equipment. The crane operator would then raise the boom which, by the way, put enormaous strain on the boom and crane as it raised the first few degrees from horizontal. Unlike the pictured crane in the OP, ours were raised by cable backstays that were in turn hooked to a gantry and more cables to improve mechanical advantage---like a gin pole on a sailboat mast. We kind of held our breath as a long boom bounced and flexed under the strain despite the skilled operators most gentle coaxing to get through those first 5 to ten degrees. Clumbsy operation could fold the boom. After that things settled down and it was easy to get to 80 degrees or so. At that point we hooked up a stack of cast iron slabs of known weights and changed boom angle specified amounts, swung the load, raised and lowered the load with sometimes vigorous braking to test the whole works. All done according the engineers direction as they came to the pad for these tests to observe how the crane and hoisting mechanism behaved. Overall it was pretty routine and somewhat boring stuff. By the way there were no load calculators or other fancy equipment on cranes in those days. The fanciest piece of technology on that crane was a very simple hinged rod with a degree scale to indicate boom angle. Gravity made the rod hang straight down and the operator could look at it to double sheck where he thought he was. That was it. All there rest depended on his experience, skil, and feel for what was going on.

However, I will never forget the day we had our newest and largest crane set up with the maximum boom it was rated for---300 feeet of combination square and round tube boom and 60 feet of "stinger" cantilevered at the top of the 300 foot section. We had made a few lighter lifts without incident and then went for the calculated max lift when, without warning, there was a creaking and bang and the whole works started twisting and falling. Usually we stood back fifty or so feet from the crane as a general safety precaution. But with 360 feet of boom up there along with the 1" diameter back stay cables and the many 50 to 75 pound cable links, gantry, hook block, and lifting cable all falling every which way, each of ran as fast as we could. Luckily no one was hurt, not even the crane operator whose only real option was to sit tight and hope. Needless to say, the relatively light sheet metal cab of the crane would have crumbled like wet cardboard had anything substantial hit it. But luck was on his side that day.

I never heard what the cause of the failure was. Suspicions were that a faulty weld might have been the cause or a tiny ding in any of the boom tubes could have been at fault. Maybe a tube had an extrusion defect.

Anyway, we did not get much done the rest of that day. The engineers beat a hasty retreat after doing a quick survey of the damage.

Once they were gone we retreated to the test pad shack for a break to let our knees stop rattling. Good times.

Denis
 
Awesome story, I am glad that it failed at a test pad and not over my grandma's house.

Ya, I guess that is why we had the test pad. Still get goose bumps when I think of that day. It would have been so easy for one of us to have been killed. One guy working in the plant did end up under a counterweight. Not good...... He was a good guy. Sad day. Things were a little looser in those days.

Denis
 
Ya, I guess that is why we had the test pad. Still get goose bumps when I think of that day. It would have been so easy for one of us to have been killed. One guy working in the plant did end up under a counterweight. Not good...... He was a good guy. Sad day. Things were a little looser in those days.

Denis

I guess, with crane booms buckling right and left, "things are still loose nowadays".
 








 
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