Harbin Electric Unveils the Largest Impulse Turbine Runner Ever Fabricated

Harbin Electric Unveils the World's Largest Impulse Runner

On December 30, 2024, Harbin Electric Corporation, a recognized global leader in power generation technology, celebrated a remarkable achievement in the hydropower sector: the successful welding and manufacturing of the largest single-capacity impulse turbine runner in existence. This monumental engineering project facilitated the launch of the inaugural 500 MW single-capacity impulse hydroelectric generator set at the Zhala Hydropower Station.

This accomplishment represents a pivotal breakthrough in China's pursuit of high-head, large-capacity impulse hydropower systems, positioning the country at the cutting edge of global advancements in this arena.

The concept of the impulse turbine is fundamental to hydropower; it utilizes a pressure pipe to direct water onto an impulse runner, facilitating energy conversion. Within the Zhala Hydropower Station, which features a design head of 671 meters, the runner is a vital component, impacting the efficiency and performance of the entire hydropower unit. Furthermore, the runner is designed to withstand significant dynamic pressures, ensuring stability during operation.

Details of the Impulse Runner

The runner crafted by Harbin Electric features a forge-welded structure composed of one hub forging and 21 bucket forgings, culminating in a post-welding weight of 90.8 tons. It boasts a hub forging diameter of 4.7 meters and thickness of 1 meter, marking the largest martensitic stainless steel forging globally. The runner achieves a maximum outer diameter of 6.23 meters and a width of 1.34 meters, distinguishing it as the largest impulse runner to date. The technological advancements in welding and processing utilized for this project reflect state-of-the-art practices.

Given the significant challenges associated with the material and design, a specialized welding technology team was assembled by Harbin Electric’s Machinery Company to tackle the intricate task of manufacturing the runner. This included utilizing digital simulation technologies to optimize die forging techniques and welding parameters. The integration of high-strength welds constructed from martensitic stainless steel ensures enhanced fatigue resistance and impact toughness, critical for the runner’s operational success.

Collaborative Innovation

In achieving this ambitious project, Harbin Electric deployed highly trained welders and craftsmen experienced in adhering to stringent quality standards amidst the confined workspaces inherent to the assembly process. The dedicated cold work sub-factory played a crucial role in merging production with technology. Lean management practices were implemented to optimize quality and efficiency throughout the production cycle, with ongoing research and multiple simulations informing the collaborative process.

Despite the challenges posed by high operational temperatures and the complexities of multi-layer welding, the welding team employed advanced welding techniques, including tungsten inert gas (TIG) and metal active gas (MAG) to ensure comprehensive quality control in the welding process. After 107 days, culminating in over 1,700 hours of diligent effort, the Machinery Company successfully completed the fabrication of the world's first 500 MW impulse turbine runner, marking a new era in manufacturing technology for electric power equipment in China.

A Leap Forward for Hydropower

This success not only fortifies Harbin Electric’s reputation as a frontrunner in impulse hydropower units but also aligns with China's broader strategy for energy innovation and the development of hydropower facilities in regions such as Southwest China. The Zhala Hydropower Station is a pivotal asset within the Southeast Xizang Clean Energy Integration Hub, recognized as one of the most formidable hydropower projects in construction worldwide, featuring advanced technologies and exceptional output capacity. With two 500 MW units, this facility has been designated as a demonstration project by the China National Energy Administration, showcasing the future landscape of energy generation technology in the country.

In conclusion, the completion of the world's largest impulse turbine runner by Harbin Electric Corporation signifies not just a triumph in manufacturing milestones but also an essential contribution to sustainable energy development in China, setting a benchmark for future endeavors in hydropower technology and innovation.