Elevator company KONE has won the contract to provide lifts and escalators for Saudi Arabia’s Kingdom Tower – set to be the world’s tallest buildings when it soars one kilometre high upon completion in 2018.
The building will be equipped 65 KONE elevators and escalators and a key to the deal was the revolutionary UltraRope hoisting technology.
KONE UltraRope is a new high-rise elevator technology that will enable elevator travel heights of one kilometre – twice the distance currently feasible.
In tall buildings the height an elevator can reach is limited by the weight of steel ropes needed to hoist it. The rope has to pull up not only the car and the flexible travelling cables that take electricity and communications to it, but also all the rope beneath it.
The job is made easier by counterweights but in a lift 500 metres tall steel ropes account for up to 75% of the moving mass of the machine. Shifting this mass takes energy, so taller lifts are more expensive to run.
Making the ropes longer would risk the steel would snapping under the load. But KONE says it is able to reduce the weight of lift ropes by around 90% with its new technology.
The company’s engineers say carbon fibres are both stronger and lighter than steel and have great tensile strength, meaning they are hard to break when their ends are pulled. That strength comes from the chemical bonds between carbon atoms: – the same way that gives such strength to diamonds.
According to Johannes de Jong, KONE head of technology for large projects, the steel ropes in a 400m-high lift weigh about 18,650kg. An UltraRope for such a lift would weigh 1,170kg.
Besides reducing power consumption, lighter ropes make braking a car easier should something go wrong. Carbon-fibre ropes should also, according to de Jong, cut maintenance bills, because they will last twice as long as steel ones.
He also said carbon fibre resonates at a different frequency to other building materials, which means it sways less as skyscrapers move in high winds—which is what tall buildings are designed to do. At the moment a high wind can cause a building’s lifts to be shut down. Carbon-fibre ropes would mean that happened less often.
The Kingdom Tower, designed by Adrian Smith and Gordon Gill Architecture, is being built by Saudi Bin Laden Group will also have the world’s fastest double deck elevators with travel speed of over 10 m/s. It will house offices, a Four Seasons hotel and serviced apartments, residential apartments as well as the world’s tallest observation spot.
”We have been highly impressed with KONE’s innovative solutions to high-rise buildings. This is another corner stone for a development of this magnitude and we look forward to creating this landmark building in all standards”, said Mounib Hammoud, CEO of developer Jeddah Economic Company.
Noud Veeger, executive vice president for KONE added: ”Close cooperation between all project partners, and with KONE Areeco team locally, our technical professionalism and people flow planning expertise was a winning combination in helping us land the order.”