I'm quite fascinated by the new(ish) 2s and 3s lifts from Leitner and Dopplemayr. I've always admired the Olympic gondola at Val d'Isere, and recently got the chance to ride the massive 3K lift at Kaprun.
For those who don't know, they're like a traditional bi-directional aerial tramway (cable car) except that they're mono-directional and the cabins detach at both end stations. They have separate track cables (that they run on) and hauling cables (that pull them along). This allows them to be bigger, and I believe, more power efficient (as the hauling cable doesn't have to be kept at such high tension and so has less frictional loss.
I'm not keen on traditional cable cars, like the Klein Matterhorn, partially because of the way that they swing when they go over a pylon, or slow as they approach the top station, but I feel happier on the 3s lifts.
I was wondering what would stop them derailing though? Is it just the geometry of the carriages and cables, or is there something more that's holding them onto the track cables?
Obviously A snowHead isn't a real person
Obviously A snowHead isn't a real person
I think you’ve answered your own question - it’s geometry. And gravity of course.
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?
They attach and detach from the hauling cable in the same way as detachable gondolas and chairlifts, using a spring loaded grip. The wheels on the support cables are concave, so wrap around the cables, with the weight of the cabin pulling them down, meaning they cant just slip one way or the other and fall off. It would take an enormous and very specific force to knock them off the cables, as it would have to push upwards, overcoming the weight of the cabin, to lift the cabin up, and then push it sideways. Even if that did happen, (it won't), the cabin is still attached to the hauling cable via the grip.
Yep. Even empty you've got a good weight pulling down on the track cables, and because they are cables rather than ridged rails even if things are swaying about the cables will flex a bit/the pulleys roll around the cable and the forces will still be pulling against the cable. The only time you might have a risk of derailing is if you started to swing past 45degrees each way - but a) that's going to be a hell of a breeze so the cable car unlikely to be running and b) I'd guess the pulling cable (that you're physically clamped to) is actually rated to take the full weight of the car as an emergency back-up.
Anyway, snowHeads is much more fun if you do.
Anyway, snowHeads is much more fun if you do.
Thanks.
I was just wondering what would happen if ice formed on the track cables, which could potentially push the rollers off them?
Last edited by Anyway, snowHeads is much more fun if you do. on Mon 14-03-22 15:49; edited 1 time in total
And I'd assume the wheels would also have brakes running either side of the cables? I'd have thought these would further discourage sideways movement.
Then you can post your own questions or snow reports...
Then you can post your own questions or snow reports...
Kramer wrote:
Thanks.
I was just wondering what would happen if ice formed on the track cables, which could potentially push the rollers off them?
This is why all lifts/cable cars etc are run for a few minutes, or laps of the lift to ensure everything is in working order, and remove any overnight icing.
After all it is free
After all it is free
kerb wrote:
And I'd assume the wheels would also have brakes running either side of the cables? I'd have thought these would further discourage sideways movement.
With cable cars and large gondolas where the support rope is essentially static I assume they have to operate within certain parameters and visual checks and as powderadict says by running the system round slowly to knock any ice off.
With mono cable systems Icing and wind are common issues that can derail ropes from sheeves, particularly on tbars and Pomas which use a lighter counterweight. With surface lifts that is not normally dangerous and is quickly fixed by lifting the rope back on.
Pylons in compression have catchers to prevent the rope hitting the ground.
In the past derailments of chairlifts, cable cars and gondolas have been caused by construction misalignment, subsidence causing pylons to Move, melting of permafrost under foundations, avalanche, falling trees, aircraft impacts, Piste basher collisions, Fires in base stations and structural failure from corrosion, Ice jacking or incorrect design. There are probably other causes too eg. Users Swinging the chair or Gondola ?
Modern rope position and tension detectors and automatic speed reduction in large wind gusts, tend to avoid catastrophic failure.