 Poster: A snowHead
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
|
Bloody hell that looks awful
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
Awful. 30 people injured, half seriously or very seriously. Wishing them all a speedy recovery and hoping the news doesn't get any worse.
Looks like an oldish chair, from the video return cable looks to have come off the pylon, can't make out if the uphill cable is also off at the pylon below.
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
|
Thank the gods the support post caught and held the cable. Perhaps it's designed that way.
|
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
Christ.
|
|
|
|
|
|
|
|
|
Shocking
|
|
|
|
|
|
|
|
|
|
|
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
|
Reading that last report I could just imagine journalists asking "But were there any foreigners hurt?"  A very, very, scary thing. And happily, a vanishingly rare thing.
|
|
|
|
|
|
|
|
Strewth, looks horrific 
|
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
@caughtanedge, looks like it to me. A very old installation, similar looking one in PdS (?) in late ‘80s (?) already dated then (?).
No safety bars? (?)
|
|
|
|
|
|
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
|
|
|
|
|
|
| under a new name wrote: |
No safety bars? (?) |
The video from Sky and RTVE shows safety bars. However one has to presume people coming into the top station and just loaded would not have it down. It would not be unreasonable to speculate that these would be the people who are most likely to have been seriously injured.
|
|
|
|
|
|
You know it makes sense.
|
| under a new name wrote: |
| ... No safety bars? (?) |
The video appears to show the empty chairs with what looks like raised safety bars above them. I think there are safety bars there. Look at the 1st frame for example. Much of the video also shows a lift fairly close to the ground.
|
|
|
|
|
|
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
|
| shep wrote: |
| Thank the gods the support post caught and held the cable. Perhaps it's designed that way. |
I am not sure it is designed that way per se. However, on this lift, the bullwheel is suspended from above, so if it did come off, the most likely scenario is that the support would catch it. However, this is not a universal arrangement. Then again, if the bullwheel is supported from below, a catastrophic failure of the bearing would likely leave it in place. The pictures show that the bearing on the bullwheel has indeed catastrophically failed. One is somewhat surprised there was not something to catch the bullwheel in the event of a such a failure. As they say, health and safety rules are written in blood, so one can imagine that updated rules will be inbound in the future.
|
|
|
|
|
|
Poster: A snowHead
|
@jabuzzard, I think you're right, although the designer could have put the post at 12 o'clock rather than 6 o'clock, with very different results in a bearing failure 
|
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
Yikes!
|
|
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
|
Looks like the bullwheel has failed in some way. It’s an inherent risk with chairlifts and other non surface lifts that if they suffer a catastrophic derailment or loss of tension the cable, the chairs and the people on them will hit the ground in places.
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
Poor design, no reason the shaft can't be supported both sides then bearing failure (if that is what happened) would be a non event. I'm not sure this is bearing failure as such rather a failure of the actual wheel due to the constant loading and unloading forces on it. Bearings in this sort of situation usually have some form of monitoring whether vibratory or acoustic, either way if that was pure bearing failure it likely would have been making a noise for some time.
Edit, even if the bearing had failed there is no way they would be relying on a press fit bearing to hold that up, something else has failed.
Last edited by You need to Login to know who's really who. on Sat 18-01-25 18:34; edited 1 time in total
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
|
@jabuzzard, @phil_w, hadn't looked too closely on my phone.
|
|
|
|
|
|
You'll need to Register first of course.
You'll need to Register first of course.
|
|
|
|
|
|
| Chris_n wrote: |
Edit, even if the bearing had failed there is no way they would be relying on a press fit bearing to hold that up, something else has failed. |
Looking at the pictures here, which show the bullwheel before failure, then it does indeed look like a catastrophic bearing failure to me.
https://www.remontees-mecaniques.net/bdd/reportage-tsf4-canal-roya-reac-4011.html
I would hazard that one or more ball bearings have disintegrated, allowing the bullwheel to come off. I feel that a catch plate held on with a large bolt through to the top would have made this incident a lot less serious. Bearing failure is definitely a thing, but generally, you get a significant warning from them because they start making a racket.
I do, however, note the historical pictures have the bullwheel painted white, and it is now yellow. Did it undergo maintenance last summer and was not correctly refitted?
|
|
|
|
|
|
|
|
| jabuzzard wrote: |
| Chris_n wrote: |
Edit, even if the bearing had failed there is no way they would be relying on a press fit bearing to hold that up, something else has failed. |
Looking at the pictures here, which show the bullwheel before failure, then it does indeed look like a catastrophic bearing failure to me.
https://www.remontees-mecaniques.net/bdd/reportage-tsf4-canal-roya-reac-4011.html
I would hazard that one or more ball bearings have disintegrated, allowing the bullwheel to come off. I feel that a catch plate held on with a large bolt through to the top would have made this incident a lot less serious. Bearing failure is definitely a thing, but generally, you get a significant warning from them because they start making a racket.
I do, however, note the historical pictures have the bullwheel painted white, and it is now yellow. Did it undergo maintenance last summer and was not correctly refitted? |
That is more or less what I am saying, there is no way there isn't some sort of "keep" on the end of that shaft.
|
|
|
|
|
|
You'll get to see more forums and be part of the best ski club on the net.
You'll get to see more forums and be part of the best ski club on the net.
|
With detail not that clear, cursory view appears to show the bearing still in situ with inner and outer tracks possibly remaining on their spigot. The "bearing" looks the same size as the hole in the wheel and could have been retained by some plate arrangement that failed. Quite a few bits of detritus on the ground in front of the wheel that could be components of this design.
Usually there's design to mitigate single failure point, or absolutely massive over capacity to keep failure essentially out of reach in normal lifing terms.
The angle of the wheel suggest that it's initially just dropped off, with the uncontained tensile load of cable immediately pulling the most extreme side of the rim down to the ground as it released.
Remarkable that the cable appears in tact (possibly cutting into the pylon leg) to partially support many of the chairs. Looks like many escaped a more serious outcome from that element "containing" further failure.
Scary experience for all involved, hopefully better prognosis than initially given by news feed of those injured.
|
|
|
|
|
|
|
|
|
|
|
snowHeads are a friendly bunch.
snowHeads are a friendly bunch.
|
|
I would expect this to be a journal bearing rather than one with a ball races or two. Looks to me like the head has sheared off the pin and the wheel just dropped off. Maybe it was overtightened or perhaps they re-used an old one when it was last serviced. Either way, someone is in line for a severe bollocking.
|
|
|
|
|
|
And love to help out and answer questions and of course, read each other's snow reports.
And love to help out and answer questions and of course, read each other's snow reports.
|
|
@altis, I wouldn't have an issue with those bearings if properly maintained, most likely the main cause is an over tightened tow cable, on a poorly maintained rig. As can be seen in the story I posted, braking issues contributed to the failure there.
|
|
|
|
|
|
|
|
@thecramps, that example looks different as part of the static structure accompanying the wheel is detached from the support pylon.
More structure loading than bearing it would appear.
The static structure in this current event appears in tact.
|
|
|
|
|
|
You know it makes sense.
|
|
@ski3, The overall point I was making was that the obvious failure is often made by less obvious problems.
|
|
|
|
|
|
Otherwise you'll just go on seeing the one name:
Otherwise you'll just go on seeing the one name:
|
|
The tension will be maintained hydraulically and at the drive station, perhaps by moving the entire motor gearbox and overhead drive wheel. The cable didn’t move that far but the sudden drop and ‘twang’ on the line will have tended to throw people around and May have caused derailment elsewhere? Must have been quite a fright.
|
|
|
|
|
|
Poster: A snowHead
|
| Peter S wrote: |
| The cable didn’t move that far but the sudden drop and ‘twang’ on the line will have tended to throw people around and May have caused derailment elsewhere? |
The video in the first report shared above does indeed show derailment elsewhere.
|
|
|
|
|
|
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
|
|
Bearing failure sounds a logical explanation. Perhaps not enough or no grease ? Though it would likely make quite a loud noise first.
|
|
|
|
|
|
Well, the person's real but it's just a made up name, see?
Well, the person's real but it's just a made up name, see?
|
| Peter S wrote: |
| Bearing failure sounds a logical explanation. Perhaps not enough or no grease ? Though it would likely make quite a loud noise first. |
Or too much grease on bodging the servicing rather than changing the bearing !!
|
|
|
|
|
|
You need to Login to know who's really who.
You need to Login to know who's really who.
|
|
I've now looked at several images of bullwheel attachment and the "undermounted" type, like the one in question, seems the most vulnerable in the event of catastrophic failure. Especially as there were no safety guard rails surrounding the wheel which might have contained it. I'll now feel compelled to look up at every one I travel on.....
|
|
|
|
|
|
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
|
| billb wrote: |
| I've now looked at several images of bullwheel attachment and the "undermounted" type, like the one in question, seems the most vulnerable in the event of catastrophic failure. Especially as there were no safety guard rails surrounding the wheel which might have contained it. I'll now feel compelled to look up at every one I travel on..... |
Funnily enough, that's exactly what I did on my first run this morning and whilst doing so spared a thought for all those people who were on that chairlift when the incident occurred
|
|
|
|
|
|
|
|
FAQ
