Photo: Screenshot of Xizang Fabu's WeChat post

Recently, the first section of the water distribution ring pipe was installed in the machine pit at the Datang Zala Hydropower Station in Southwest China's Xizang Autonomous Region, marking a significant milestone for the world's largest single-unit capacity impulse turbine, as it enters the core installation phase, Xizang Fabu reported on Sunday. 

This 500-megawatt (MW) unit not only sets a new record but also turns into reality the blueprint for Xizang's first million-kilowatt-level hydropower project and the "strategic pivot" of the clean energy base in Xizang into reality.

Maneuvering a 411-ton "steel and iron" structure into a high-altitude canyon was a formidable clash between technology and nature. The water distribution ring pipe, measuring 28 meters long, 25.2 meters wide, and 4 meters high, was divided into 13 segments for transport. 

The first hoisted section, resembling a "giant bullet" with a 3.1-meter diameter and 95-millimeter wall thickness, weighed 32.1 tons. It was precisely positioned with millimeter-level accuracy by a 400-ton crane in the thin air and confined space of the machine pit, the report said. 

From a technological perspective, the Sinohydro Bureau 7 Co Ltd employed Building Information Modeling (BIM) for 3D modeling and 1:1 physical mock-ups on the plateau, simulating the process digitally before on-site execution. In collaboration with universities, the team developed an 800-megapascal high-strength steel welding process, enabling one-time hoisting with real-time adjustments.

On July 2, the world's first single-unit 500 MW impulse turbine, developed by Harbin Electric Machinery Company Limited for the Datang Zala Hydropower Station, was delivered. The independently developed impulse turbine consists of 21 precision water ladles, with an outer diameter of 6.23 meters, a thickness of 1.34 meters, and a weight of about 80 tons, Xinhua News Agency reported. 
 
Global Times