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Crane crushes house while delivering pool

JamieK

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Aug 13, 2009
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Winston-Salem, NC
Not trying to take up for the operator here, but was it possible that he just grossly underestimated the weight of the hottub, or the weight was told to him wrong? A crane operator can't conceivably know the weight of every thing he lifts; someone has to tell him.
 
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Zick

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May 13, 2009
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WI
Not trying to take up for the operator here, but was it possible that he just grossly underestimated the weight of the hottub, or the weight was told to him wrong? A crane operator can't conceivably know the weight of every thing he lifts; someone has to tell him.

Actually they can, some crane have a computer that can display how much weight their lifting.
 

Ironcrow

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Sep 30, 2005
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Arizona
1. The load charts should still be used by operators to double check the electronics.
Yes. I agree. Look at the chart. But, in my opinion only because the electronics are non-existent or lame. I have not examined one of these charts closely, but as I recall they list load allowed at boom angle and extension.

But, the operator may not have an accurate weight. If it is provided, it might not be correct. The load may not include the block or ball. Or jib if its laid back against the boom. The tipping moment is also controlled by the amount of cable paid out and its mass. What if one outrigger is pulled a little short to clear an obstacle? Sure a skilled and careful operator can take all this into account.

But, this is the sort of thing a computer can easily do. Better, faster, and more dynamically than a guy with a piece of paper. Add a pressure sensor at each outrigger foot. Add a strain gauge at the end boom pulley. Add a linear encoder to feed boom extension to the computer. Add a boom angle signal. Write the software. In my mind the cost of these sensors (cheap) and their reliability (very high) would increase the speed and safety of the crane set-up and use. On to the next paying job.

2. The feet on outriggers arent designed in most cases to support anything even close to the machine's load in most applications, theyre simply designed to fit within the given space confines and/or be easily lifted in the case of detachable feet. Its an understood and widely used practice to use timbers or large steel mats to distribute the loads better, and in most cases is necessary.
"In most cases necessary"...yeah, why does a guy trying to make money tolerate that? A foldable/collapsable foot does not seem like a serious design challenge to me. I've got a $1000/hour job (equipment and labor - crane, crew, people leaning on shovels waiting for the crane guy to get set up...) and it takes the guy 1/2 hour to roll out his timbers and stuff and shove them under each foot. Lose that time ONE job a week and I've got $52,000 to start my ROI on making the more complex foldable feet....
Unfortunately we live in an era of "not my responsibility," and its sad. Oops! Good thing Ive got insurance. :willy_nil
Very true, yes, but that's a whole nuther thread :beer:
 

slammedstepside

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Sep 21, 2010
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Alberta, Canada
Operator error, no two ways about it. The electrical systems in cranes are a failsafe; they are not in place so that the operator doesn't have to do his job. You sit down with a load chart and a paper and figure out your lift before you do it. This is the single most important thing they drill into your head when you do your training. If you can't/won't do the proper pre-lift planning, you have no business doing the lift. In fact, when I got my ticket, if you failed the load chart portion of your test, it was an automatic fail on the spot. You didn't get the chance to touch the truck. You need to know how to plan out a lift properly, not trust what the computer says. For what it's worth, he probably put something into the computer wrong anyways which would have thrown everything off, but that still doesn't excuse him from not doing the proper work. It would still come down squarely on the operators shoulders, as it should.
 

rvr6000

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Oct 3, 2010
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1,072
Location
St. Paul, MN
KME=Keeping Mechanics Employed!

Every department I know that has a KME, only bought one. Cabinets completely falling off, stress fractures in the boom of a 6 month old 100' mid mount. Best of luck with that truck, but keep a good eye on it.

We've had the Grumman for almost 30 years now....I forget what year Grumman went bankrupt and KME took over. It hasn't been too bad of a truck for us....only twice has it left me stuck up in the air only have to climb all the way down....haha Still has a good strong pump (Waterous) though and has moved a lot of water in its day.
 
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iagsxr

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Jan 10, 2010
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Location
Vinton, Iowa
its amazing how all these internet-crane-operators can call it toally operator error, without ever operating one, or most likely even standing next to one.

Mostly this:withstupi

I've craned hot tubs. They're deceptively heavy. The people that sell them typically don't know **** about setting them.

Think I see some errors in the operator's technique, but I wasn't there. He may have had reasons for doing things that are obviously wrong after the fact. I think I could make that lift, that crane, no counterweight.

All that being said, my old man's retiring. We're selling our cranes in five weeks. I couldn't be happier. It is my opinion that if you do it long enough you will have an accident.
 

Ironcrow

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Sep 30, 2005
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Location
Arizona
Saw this on the news, it was apparently being blamed on misinformation of the weight of the tub.
Yup. You could stare at your table all day and if the provided weight of your load is not correct the table doesn't do you any good. A problem that could be solved with automation.
 

Boost Creep

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Feb 17, 2010
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1,407
Location
michigan
well obviously the operator should have brought his bathroom scale to work with him to check the weight so its still operator error
 

Shadowdog500

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Dec 7, 2009
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Down the shore
I just looked and they do make scales to go between the cable and the load to check or confirm the weight of what you are lifting. I never operated a crane in my life, but if weight estimates are sometimes off, I imagine this would be cheap insurance.

Chris
 
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