Skyscrapers help test elevators

On the eastern edge of Germany’s Black Forest mountains, just outside the medieval town of Rottweil, lies a strange structure – an uninhabited skyscraper. This building is called TK Elevator Testturm, is 246 m high and is one of the tallest buildings in Germany.

However, the lack of windows shows that this skyscraper does not contain offices or luxury apartments. The main purpose of the building lies deep inside: 12 elevator pits used to test the latest elevator models.

In addition to the TK Elevator Testturm, German elevator manufacturer TK Elevator also has a 128 m high test tower in Atlanta and a 248 m high test tower in Zhongshan, China. The test towers could go higher still. For example, Tower H1 built by Japanese corporation Hitachi in Guangzhou, China, is 289 m high. This is one of the tallest buildings in this city full of skyscrapers, and will even be among the 25 tallest buildings in New York City and the third tallest in Los Angeles.

“The main and most important reason why test towers exist is to verify certain safety functions that can only be performed in a real environment,” said Tomio Pihkala, chief technology officer at the ladder manufacturer Finnish machine Kone, said.

Kone, the company that installed elevators at Taipei 101 (the world’s tallest building in 2004 – 2010), opened its first test tower in Hyvinkää, Finland, in 1967. Since then, the company has built four more. Another test tower, the tallest of which was completed in Kunshan, China, in 2015 with a height of 236 m.

“In the test tower, we enhance the actual operating conditions of the elevator and eliminate the presence of normal users. It is also a great location to verify quality, comfort and elevator reliability,” Pihkala explained.

In the safety tests there is one that simulates a free fall situation. “It’s not a real elevator but an object of equal mass. This is when the emergency brake system and safety devices must activate to safely stop the elevator, ensuring no one is inside.” injured,” Pihkala said.

Some test towers are especially tall because most modern elevators are so fast that they quickly run out of track. “When you have faster elevators, you need a taller testing tower. High-speed elevators move at more than 30 feet per second, and to test that type of elevator, you need enough space to get up to that speed.” maximum speed, then decelerate,” Pihkala added.

However, building upward is not the only option. In fact, the world’s longest elevator testing facility is underground. Located in Tytyri, Finland, the structure is part of an active limestone quarry and reaches a depth of nearly 350 m. “This is something unique in the industry. We have reached an agreement to use some pits in the mine, which will help test elevators for buildings up to one kilometer high,” Pihkala said.

At this facility, elevators can be tested at speeds of up to 19 meters per second. During free fall tests, the 9,980 kg elevator frame reached 26 m per second. In total, the mine has 11 holes with a total length of nearly 1.6 km.

Like all skyscrapers, elevator towers need to withstand strong winds, which can cause vibrations and affect testing conditions. So some towers are equipped with mass dampers – essentially a giant pendulum that resists shaking caused by severe weather, even earthquakes. About 1/3 of the 20 tallest buildings in the world have this device installed.

However, for engineers wanting to test elevator technology in extreme conditions, this mass damper can also be used in the exact opposite way – creating vibrations. The TK Elevator Testturm tower in Rottweil has a 200-ton shock absorber suspended by four steel cables, which can be moved by two motors. It creates oscillations that simulate wind and earthquakes – two of the biggest challenges when developing elevators.