A ship climbs onto the ship lift at the Three Gorges Dam in Yichang, Central China's Hubei Province on July 11, 2023. Photo: Courtesy of China State Shipbuilding Co

How to lift a 3,000-ton ship to a height of 113 meters above the ground? An elevator located in Yichang, Central China's Hubei Province, can achieve that feat in just 40 minutes.

Standing inside it and look around, the device, the largest of its kind in the world, looks more like a giant building rather than an elevator - an engineering miracle that vividly displays the country's manufacturing strength. 

The scale, lifting height and lifting capacity of the elevator surpasses those of several famous overseas ship lifts by about 1.5-3 times, making it the largest and most technologically challenging ship lift in the world, Huang Xing, a senior executive at Wuchang Shipbuilding Industry Group Co, the manufacturer of the lift, told the Global Times on Tuesday.

"For example, the Strépy-Thieu Boat Lift in Belgium has a capacity of 1,000 tons and a lifting height of 70 meters, while the Luneburg Elbe-Seitenkanal Lift in Germany has a capacity of 1,350 tons and a height of 38 meters," Huang said.

The greatest feature of the Three Gorges Ship Lift is its emphasis on safety. With four sets of symmetrically arranged drive mechanisms using gears and racks, the ship chamber is rigidly supported at four points, effectively preventing the amplification effect caused by water tilting or swaying inside the chamber and minimizing the risk of chamber overturning, Huang introduced.

An inside view of the ship lift at the Three Gorges Dam in Yichang, Central China's Hubei Province on July 11, 2023. Photo: Courtesy of China State Shipbuilding Co

"Furthermore, we have implemented buffer and damping mechanisms in the ship chamber to absorb impacts and vibrations. This means that even in the event of an earthquake while the ship lift is operating, the seismic forces will be transmitted to the tower columns, instead of causing the chamber to fall or any major accidents," said Huang, who has participated in the ship construction process.

These measures ensure the safety of the ship lift by preventing significant incidents and providing a stable and secure operation even in challenging conditions, he added.

The lift is currently one of the permanent navigation facilities at the Three Gorges Dam. Its main purpose is to provide a fast passage for passengers and cargo vessels, as well as special-purpose vessels, through the dam. 

The designed time for a vessel to pass through the ship lift is approximately 40 minutes, significantly shorter compared with the 150 minutes required to pass through the ship locks. This has resulted in a significant reduction in the time required to navigate through the dam, an onsite staff at the dam told the Global Times on Tuesday.

"Some bigger ships still have to use the five-stages of locks at the dam," the staff said.

An inside view of the ship lift at the Three Gorges Dam in Yichang, Central China's Hubei Province on July 11, 2023. Photo: Courtesy of China State Shipbuilding Co

The efficiency brought by the elevator greatly has enhanced efficiency of the transportation, and provides strong support for ensuring smooth navigation on the Yangtze River.

In the first half of the year, the Three Gorges Dam has witnessed a shipping throughput of 84.15 million tons, a 9.32 percent year-on-year increase and a new historical high in terms of shipping throughput, according to a notice published on the official WeChat of Three Gorges Navigation.

This year marks the 20th anniversary of the dam's operation. The total cargo throughput via the ship locks at dam, the world's largest hydropower project, has exceeded 1.91 billion tons, the Three Gorges Navigation Authority said on June 19.

During the past two decades, more than 993,000 ships with about 12.24 million passengers passed through the ship locks, located in the upper stream of the Yangtze, which is China's longest river.

The Three Gorges project is a multi-functional water-control system, consisting of a 2,309-meter-long and 185-meter-high dam, five-tier ship locks on the north and south sides, and 34 turbo-generators with a combined generating capacity of 22.5 million kilowatts.