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Engineers Develop 'Ultrarope' For World's Highest Elevator
HughPickens.com writes: Halfway up the Shard, London's tallest skyscraper, you are asked to step out of the elevator at the transfer floor, or "sky lobby," a necessary inconvenience in order to reach the upper half of the building, and a symptom of the limits of elevators today. To ascend a mile-high (1.6km) tower using the same technology could necessitate changing elevators as many as 10 times. Elevators traveling distances of more than 500m [1,640 ft] have not been feasible because the weight of the steel cables themselves becomes so great. Now, after nine years of rigorous testing, Kone has released Ultrarope — a material composed of carbon-fiber covered in a friction-proof coating that weighs a seventh of the steel cables, making elevators of up to 1km (0.6 miles) in height feasible to build.
Kone's creation was chosen to be installed in what's destined to become the world's tallest building, the Kingdom Tower in Jeddah, Saudi Arabia. When completed in 2020, the tower will stand a full kilometer in height, and will boast the world's tallest elevator at 660m (2,165ft). A 1km-tall tower may seem staggering, but is this the build-able limit? Most probably not, according to Dr. Sang Dae Kim. "With Kingdom Tower we now have a design that reaches around 1 km in height. Later on, someone will push for 1 mile, and then 2 km," says Kim. He adds that, technically speaking, 2 km might be possible at the current time. Anything higher would require new materials and building techniques.
Kone's creation was chosen to be installed in what's destined to become the world's tallest building, the Kingdom Tower in Jeddah, Saudi Arabia. When completed in 2020, the tower will stand a full kilometer in height, and will boast the world's tallest elevator at 660m (2,165ft). A 1km-tall tower may seem staggering, but is this the build-able limit? Most probably not, according to Dr. Sang Dae Kim. "With Kingdom Tower we now have a design that reaches around 1 km in height. Later on, someone will push for 1 mile, and then 2 km," says Kim. He adds that, technically speaking, 2 km might be possible at the current time. Anything higher would require new materials and building techniques.
No, you could use a conductive rail, like a subway, and rack and pinion system to move the elevator. The rack and rail would add a fair bit more total weight to the building compared to a cable. But more importantly, the motors would have to be much much more powerful! Modern elevator systems have a counter-weight balanced on the other side of that cable, which means the motor only has to overcome friction and the small difference in weight between the elevator and counterweight (which varies depending on current payload). The motor on an elevator like Noah is suggesting would have to provide enough force to counteract the entire weight of the elevator + payload + motor + friction, which is at least an order of magnitude more than a traditional elevator.
Calling out a person for behavior you present is not going to change anything.
The main problem with rails is that you need a sliding contact. That means arcing at the contact when the air gaps are eventually going to occur (nothing is 100% flat, and air pockets will eventually get between the contact and the brush). Arcing isn't going to cause immediate failure; but, it will leave a carbon / oxidation residue at the arc site. This means that future electricity will have to flow through a very small scale resistor, generating heat. Eventually the heat will cause pitting, accelerating failure.
This is why most in-wall electrical sockets are designed to scrape the plug slightly on insertion. It is a self-cleaning feature of electrical wall sockets, and any wall socket that doesn't provide some modicum of resistance when inserting a plug should be replaced as soon as possible. A loose wall socket will not clean the prongs on the plug, carbon will build up within the socket, and the heat will eventually lead to arcing that will melt the plug, the socket, or both (possibly starting a fire as a side effect).
The issues of contacts on long electrical rails can be fixed by turning the rails into flexible cables; but, that only recreates the cable problem. Even though an electrical cable could be theoretically lighter than the lift cable, it still has to lift its own weight, and an under-built electrical cable cannot entertain even micro-fractures in electrical conductivity without have an accelerated repair cycle.
Now you know why virtually all elevators use cables for lifting with a fixed motor.
Linear Synchronous Motor Elevators Become a Reality
With a magical lightweight power cord, perhaps?
The British already have a twenty mile long extension cord that they use to power the trains going through the Channel Tunnel. They reel it out as each train goes through, and then wind it up afterwards to prepare for the next train. There is no other way to do it, since it is totally impossible to transfer electricity to a moving object through, say, a power rail.
I'm probably going to lose some karma for this...
I, too, could come with a half-dozen answers that would be "far superior" to what 100+ years of the finest minds in the industry could come up with. But in reality, I really, seriously doubt that my designs would hold up because there's a *reason* that things are done the way they are.
Mechanical engineering is a *very old* industry, and any radical, new design would have significant hurdles to pass before it could be accepted and used in a real scenario. The cost of failure is very high and there are real lives on the line.
My first thought was to use something like a caterpillar drive along the sides of the shaft, each of which would operate like a mini elevator for perhaps 10 floors. But, very quickly, I can see that this type of system would have many, many more moving parts and consequently many more points of failure.
So, I think it *might* be best to trust that 100+ years of experience are, in fact, at work, and that we should first understand that there is *real knowledge* at work before assuming that our half-baked and thoroughly unproven ideas hold any merit in reality.... ?
I have no problem with your religion until you decide it's reason to deprive others of the truth.
Maybe we should apply this great cable technology to subway trains. I do notice the pits on the third rail. They always have to send some poor guy out to sand them out real quick before the next train comes.
“He’s not deformed, he’s just drunk!”
Train rails are excessively thick. This coupled with scrubbers around the brushes means that the rail is cleaned prior to contact, and the wear of the (cleaner) rail is minimized. This coupled with the minimal movement of a ground fixed tie and a very large amount of metal to wear through leaves the effective life of the rail in the +10 year range (if not +50 year range).
A building will have few of these advantages. Buildings in the 30+ story range sway. Excessively thick rails get far more expensive to run vertically, so the rail thickness will be minimized. This increases the chance of flex and decreases the amount of rail to wear out by scrubbing or pitting. It isn't that it can't be done, it's just that it can't be done easily, which translates to cheaply.