Escalator accident in Stockholm subway

[Skogsgurra]

An escalator went amok a few days ago. Started moving backwards with lots of people on it. Speed way above nrmal. Brakes didn't work.

Coupling bad, was my first thought. Today, there is a picture in the papers showing the coupling.

The press spokesman (yes, a male)said that the accident was caused by rust. I can't see much rust on the part. But fretting in the splines. And I guess that the correspondning shaft is even worse. So, no wonder that E-stop didn't work.

Comments?

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[jraef]

We may not live to see the end of the lawsuits, but based on trends I see happening, I’m going to toss in sloppy workmanship in installation and/or maintenance. I see people foregoing taking the time to properly align motors into gearboxes all the time now, usually under duress from management to just “get ‘er done” and back on line. Then the splines, couplings, bearings and shaft keys fail and again, management just tells the mtc crew to replace it quickly then blames suppliers for excessive failures. I recently had a meeting at a big pharma plant because they are having excessive bearing failures in motors and gearboxes and the mechanical suppliers are blaming the VFDs for it. But the failures are not the typical fluting seen from that issue, they are just plain worn out, plus they are saying that the VFDs are also chewing off splines and breaking shaft keys. I asked if they are using laser or visual alignment, the mtc mgr looked at me like I had two heads, then told me they had no time for such foolishness...


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden

 

[edison123]

Gunnar

Yup. I wanted to see if I had won 1000 bucks overnight. Bill let me down.

Jokes aside, I would like to know the root cause(s).

Muthu

http://www.edison.co.in

 

[LionelHutz]

jraef - VFD's definitely can cause keyways and shafts to break, but that's another story.