Lately there has been a breakthrough in elevator technology to achieve unthinkable speeds a few years ago. Moreover, in a short period of time it is quite possible that the maximum speed of the elevators reach figures of more than one thousand meters in one minute.
To achieve these high speeds it is necessary to develop very powerful motors, systems to control the pressure inside the cabin and achieve greater lengths in the cable that holds the elevator, such as those developed by Astarlifts.
Next we will go over the list of the three fastest elevators in the world to get an idea of the order of magnitude of speeds we are talking about.
The list is led by the elevator installed in the Shanghai Tower Building. This building is located in Shanghai, China. It has a height of 634 meters and is the second building in height, after the Burj Kalifa Building, with a height of 828 meters. Its design was run by Gensler and is owned by the Shanghai government. Its construction began in November 2008 and ended on August 3, 2015.
However, in terms of elevator speed, it ranks first in the standings with a top speed of 20.5 meters per second or 73.8 kilometers per hour. To achieve this speed, the company has invested heavily in developing the technology through a control system, accessible from a control panel, which is capable of optimizing the performance of the traction motors. In addition the elevator has built-in security systems of last generation as speed limiters, braking devices and damping.
Guangzhou International Finance Center
The second on the list of the world's fastest elevators corresponds to the one installed in the Guangzhou International Finance Center Building. This building is located in Tianhe, China. It is a tower of 103 floors and 439 meters high. It was designed by Wilkinson Eyre, it began to be built in 2006 and was completed on December 31, 2008.
This lift is capable of ascending at a speed of 20 m / s.
The world's third-fastest elevator is located in the Taipei 101 Building. With a height of 508 meters it was the tallest building in the world between 2003 and 2010 until the Burj Khalifa Building mentioned above took away the title. It is located in Taipei and also boasts the highest ecological building title in the world. As a curiosity you can say that it is built in an area of high seismicity.
The maximum speed of this elevator is 1010 meters per minute, and as for a time this elevator was the fastest in the world, at the entrance of the building there is a commemorative plaque with the certificate of the Guinness Prize.
To speak properly of this elevator we should say that these are two high-speed elevators. In order that users do not notice the typical discomfort of the pressure changes, these elevators are equipped with a system of regulation of the atmospheric pressure. On the other hand, to achieve a greater energy efficiency during the transport, they have been designed with an aerodynamic form that minimizes the friction of the elevator with the air during the rise and during the descent.
To achieve these high speeds the elevator has high power traction machines as well as a high reliability control system.
As we have seen, the increase of the speed in the elevators brings with it a development in the control and safety systems of these. Below we will explain which are the safety systems that contribute to a trip in one of these lifts minimize the risk of accidents.
If the speed limiters in the elevator detect an abnormal increase in the speed of the elevator, then the parachutes that are housed in the elevator guides come into action, causing a gradual braking of the same. The parachutes are nothing more than wedges that bite the elevator guides. In the case of high-speed elevators, and for obvious reasons, the braking should be done gradually, otherwise the deceleration would be so great that it could lead to some kind of accident among travelers.
At this point it should be added that, due to the high speeds, these emergency braking systems can overheat and, therefore, special care must be taken in the choice of suitable materials.
The door locking system, which is controlled from the elevator control panel, prevents the doors from opening when the elevator is ascending, descending, accelerating or decelerating. This prevents the possibility that some user can exit this during the movement.
Request for help
In all high-speed elevators there is a panel that can be accessed in a state of emergency. In this way it is immediately contacted from abroad so that the relevant actions can be taken.
Some countries allow the elevator to communicate directly with national emergency services so that emergency resolution is much faster and more efficient. These types of bells have an Uninterruptible Power Supply (UPS), ie in case of power failure, these energy storage devices would come into operation to provide both the emergency lighting and the emergency call panel .
End Shock Absorbers
End-of-travel dampers allow gradual braking when the elevator approaches the lower or upper limit of the ride.
Photocells and sensitive edges
They are fundamental to avoid accidents during the filling and evacuation of elevators. They capture the presence of objects in the vicinity of the closing of the doors and do not allow them to be operated until the area is free.
Finally we will address a rather interesting topic which is the reduction of air resistance in this type of lifts. It is evident that at such high speeds, the friction of the elevator with the air is a crucial issue and that a good design of the elevator can reduce such friction considerably.
A reduction in friction leads to a reduction in the energy consumption of the building and this is a topical issue, since it tends to design buildings as efficient as possible from the energy point of view.
The piston effect is a phenomenon that occurs in high-speed elevators. This effect is evidenced when an object is moved over a closed tube filled with a fluid and the object occupies a large part of the tube section. In this case the object would be the elevator, the tube the elevator shaft and the air fluid. Because of the speed of the elevator, a very large pressure is created in the air that is in the direction of advance of the march because the elevator occupies almost the whole section of the gap and the air has hardly a section to escape.
As a result of the overpressure of the air that is in front of the direction of advance of the elevator, a depression is created in the area of the cabin. It is for this reason that high speed elevators have hermetic seals and compensation systems for the depression brought about by this piston effect. This is a phenomenon very similar to what happens on high-speed trains as they pass through tunnels. These tunnels must have a suitable section so that the consecutive overpressure and depression in the cabin are not so high that the materials are not able to withstand them.
To achieve that the piston effect is minimized you have to get an aerodynamic design of the lift. To give an example, if the elevator were rounded at its tip, similar to a rocket, we would get the air not to suffer such an exaggerated and sudden compression and, therefore, would not cause such a high overpressure. Failure to create such a high overpressure would also minimize depression in the interior of the elevator and would therefore be more comfortable for travelers.
Another important effect is that which occurs in the narrow space between the walls of the elevator and the gap. In this zone there is an increase of the air speed and, consequently, a ground effect, similar to the one that occurs in the cars of Formula 1
As a conclusion we can say that high-speed elevators are a very suitable technology for buildings that exceed 500 meters in length, but that it is necessary to invest in good security systems, a good control system and, last but not least , In a good aerodynamic design that minimizes the problem of the depressions inside the cabin.