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OT- *140 ton* overhead crane problems ??

Milacron

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Was watching a show last night about building the Atlas particle accelerator (part of the Hadron superconducting supercollider) in Switzerland, where they were assembling the electromagnets sections by lowering them something like 100 feet down a huge tube, with a *140 ton* overhead traveling crane (i.e. like in many manufacturing facilties..just waaaaay bigger). Magnet (don't remember weight...maybe 100 tons) was about 30 feet in the hole and the crane started making these ungodly loud banging noises, so they had to stop and pull it back out rather than risk going another 80 feet.

Load just hanging there not moving, noise was "bang" "bang"...etc with about 2 or 3 seconds between "bangs"

Anyhoo, problem was supposedly "bearings" in the crane and I'm thinking screw the supercollider, I wanna know what and why the bearings went out in this crane ! (which looked brand new and was probably only a few years old at most) Naturally they glossed over that whole aspect and just came back the next day with it "fixed" and lowered the magnet again.

So, any idea what exactly could happen to a nearly new crane bearings that size being utilized well below it's rated capacity (hellacious as that is) ?
 
Ask Joe Michaels. The crane in his power plant probably has a capacity of 500 tons or so. A 140 ton crane is nothing in a power plant.

My guess is that it was not the bearings, not if they fixed it in a day. I would guess it might have been the brake. Brakes on overhead cranes are spring applied, electrically released. If something was wrong with the power supply to the brake, it might possibly go on and off, and make noise.

Thermo1
 
D.
Just because they said it was the bearings on TV doesn't mean it really was, they get it wrong most of the time even if they are given the right info from the people who are in the know!! I know this from experience with TV film crews.


Jackmo
 
Thermo...that's what I was thinking...it seemed more like a braking issue to me. I've heard similar sounds when large hydraulic jacks are slipping down in sudden increments. But the guys in the know were right there on the set and said "bearings" so I just figured they knew what they were talking about. But agree also that is was mighty suspect they could fix a bearing issue in one day...especially considering there must be some hugemongeous roller bearings in that thing. Plus I don't think Motion Industries has a Swiss bearing division ;)
 
D. Thomas,
The other aspect is that if they say "brakes", they might have to explain, but will not have enough time in the segment to explain, but if they say "bearings", no explanation needed. Just a guess.

Thermo1
 
D.Thomas,
Brand new brakes can stick. I just remembered the only time I was stuck in an elevator. The State Elevator Inspector was in the cab with me. It was the final inspection, the elevator mechanic was in the machine room. No big deal, the mechanic just had to back off an ajustment on the brake.

Thermo1
 
All I know is if I was there my skin would have been crawling and all hairs standing on end hearing that banging sound while looking at 100 tons of magnet dangling 80 feet over a gazillion dollars worth of equipment. (not to mention the $$$$$ in the magnet itself, and the $$$$$$ in project delays that would cascade thru the system) Would have been one of, if not the most spectacular and expensive crashes in modern history if the brakes or cables failed completely !

The Atlas particle accelerator, currently being constructed as part of the Large Hadron Collider which spans two countries, is at CERN in Switzerland. Hadron in total is the worlds largest "machine" btw.
 
Probably just a bunch of wrenchs that people dropped down the hole stickin' to the magnet.

SM
 
I performed monthly vibration analysis on a 310 ton main hoist for many years. We would ride the trolley up and down the house while the crane worked to get the readings done. Once it completely threw a brake shoe. Now that got our attention when she went to brake with a 100+ton load and a brakeshoe missing on one side of cable drum. Bearings on the hoist were large and very reliable. I was always amazed at how often they changed out the cables.
 
if I were in charge of that and my screw up caused the part to fall and cause 10 zillion in damages, I might take the 13 cent solution [ie a bullet]. just kidding
 
The Stanford Linear Accelerator collision building has two very large (50+ ton) cranes that I saw when I took a tour there. The machine/welding shop is literally next to the workpit, so they can literally bring in the crane, lift a part off the machine, and lower it into place.

Don, while an electromagnet will be significantly weaker when off, its iron core will often have a ghost magnetic field after the current is switched off. Assuming they tested this electromagnet before installing it, it could be a potentially strong magnet even after being shut off. Unlikely though.

I have a number of physics professors who look at the plans for the Hadron superconducting supercollider and just either scoff or get pissed. High energy particle physics has started to get rediculous. High energy particle physics is one of the fields of physics with the least likelihood of ever being of use to regular humans. Compare the discovery of something like the Higgs boson to fusion power (direct application to the energy issue) or the controlled manipulation of Bose-Einstein Condensates (potentially the most accurate solid state gyroscopes ever.. The navy is investing heavily in BEC research for missile guidance systems), and large supercolliders are a waste (for now).
 
Halco, re "waste"....any idea where the bazillion Euros is coming from to fund the Hadron project ?
 
if I were in charge of that and my screw up caused the part to fall and cause 10 zillion in damages, I might take the 13 cent solution [ie a bullet]. just kidding
Nah just say OOPS Sorry.You'd be surprised what the word 'sorry' can accomplish :D

Don
Probably from the Airbus Super Jumbo profits
Lets count the chickens.... :D
 
Super JUmbo profits???
Just about to become a bitch fight twixt the Germans und Frensch.

I would also think hoist brake(s).
Even the itty-bitty P&H I ran would do tricks to get your attention.
 
I worked on the failure of the slewing ring bearing for a tower crane. It was about 6 ft diameter, and hadn't been heat-treated correctly at the factory. The balls chewed the inner race to bits. So yes, it is conceivable for a brand new bearing to go belly up.
 
My guess is that it was not the bearings, not if they fixed it in a day. I would guess it might have been the brake.
"Funny" noises are most often somewhere in the brake. Not necessarily the friction surfaces, sometimes one of the shafts or a shaft bearing.

When a big load's swinging, any noise gets noticed FAST.

------------
Barry Milton
 
I saw that show too.If you listened close you would have heard that they switched to backup crane.That was a very interesting show.I missed the first part.Hope to catch it again.BIG BUCKS for sure!
 
JK....backup crane ? Was there a second hoist on the gantry ? Makes sense but I only saw one hoist. Coulda sworn I heard them say "fixed" with regards to the crane bearing problem.
 
If the bearings did really go bad, to the point they couldn't lower it, how did they get it back up?
Dicey deal, I imagine.
 








 
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