On the afternoon of August 22, 2018, a special 10KV suspension cable with a length of 820 meters and a weight of 8 tons was successfully hoisted on the 100th floor of China Zun under construction, the tallest building in Beijing. It symbolizes the successful completion of 24 high-voltage suspension cables with a total length of 15,132 meters on China Zun by Far East Cable. The total weight of the cables reaches 136.38 tons. Among them, the cable installed this time reaches 820 meters and 8 tons, which is the heaviest in the world.    

How was the "longest cable in the world" developed?

Pain points and challenges of R&D

China Zun is 528 meters in height. Such a super high-rise building has a large volume, a large power consumption, and a long power supply radius, while the strong electric well for hoisting is only 0.45 meters in width.

If we use the traditional 10kV steel wire armored cable directly supplied from the bottom high-voltage main substation to the sub-substation above, the cable must be bundled and installed with the bridge frame when being laid in the vertical shaft, which will take up a large space, and the steel wire armor will have large eddy current loss, which is not economical. Therefore, it is necessary to develop a new cable to solve the following pain points:

•  The cable is heavy in weight, how to ensure its long-term safety and stability?
•  How to save the space of the shaft and improve economic efficiency?
•  How to reduce the difficulty of construction and installation?

Innovative R&D of self-bearing cables

The high-voltage cable will continuously supply energy to the building's electrical core, so its safety and stability are very important.

The power supply cable is too long and heavy and thus is easy to be strained by its weight during long-distance vertical laying. How did Far East Cable break through this technical bottleneck?

Flame-retardant hanging cable and fire-resistant hanging cable

Far East Cable innovated and developed self-bearing cables. Three steel wire ropes are embedded in the vertical section of the cable and equipped with hoisting discs. The wire ropes are twisted with three cable cores. During hoisting and long-term power-on operation, the steel wire ropes and hoisting discs are stressed. No matter how long or how heavy, it can support its own weight and effectively guarantee the safety of the building's power supply system. After this patent was first used in the construction of the Shanghai World Financial Center, it was once again perfectly displayed in the China Zun project.

Exclusive laying plan

The electric design for China Zun is exclusive, especially for the cable arrangement in the strong electric well. In the narrow shaft, we need to place 10 10kV cables and 6 1kV low-voltage cables with a rated voltage. With the narrow space and so many cables, it is hard to ensure their safety and feasibility. However, the Far East R&D technology innovation team and the China Construction and Installation Company have planned, discussed, modified many times, and finally innovatively come up with a new type of arrangement and a one-plate double-hanging load-bearing spreader.

The world's longest special 10kV high-voltage suspension cable successfully hoisted in China Zun

After two years, Far East Cable perfectly constructed China Zun's "aortic vessel" by laying 24 suspension cables with a total length of 15,132 meters and a total weight of 136.38 tons, including the "world's first" 820-meter special 10kV suspension cable.

Appraisal of world leading product by authorities

On December 24, 2017, at the "New Product Appraisal Meeting for Far East Cable 2017" organized by the Jiangsu Economic and Information Commission in Yixing, the experts unanimously appraised the "super-high-rise building hanging cables and cranes" submitted by Far East Cable Co., Ltd. with their safe and environment-friendly features such as low-smoke, halogen-free, flame-retardant and fire-resistant, which can improve the power supply quality of super high-rise buildings. Their comprehensive performance has reached an international leading level.

With the maturity of structural safety technology for modern buildings, super high-rise buildings have sprung up on the Chinese land at a rapid speed, and the hanging cables for super high-rise buildings by Far East are exclusively designed for this trend, breaking the monopoly of cable technology abroad and making Chinese wisdom and Chinese technology seen and praised.