On December 9, the water diversion surge shaft and vertical shaft of the Guangdong Zhaoqing Langjiang Pumped Storage Power Station, constructed by Sinohydro Bureau 4 Co., Ltd., were successfully holed through, laying a solid foundation for the efficient coordinated operation and stable functioning of the station's subsequent water conveyance system.

This vertical shaft is currently the largest-diameter and deepest vertical shaft under construction in China. Facing difficulties such as high construction difficulty, a lack of construction methods, a tight schedule, heavy tasks, and poor geological conditions, the project team actively optimized the construction plan by combining the layout of the water diversion surge shaft and the vertical shaft, turning the vertical shaft from "two into one," further improving construction methods, and proposing a construction method combining raise boring and downward drilling for large-diameter deep vertical shafts, which has now obtained a provincial-level construction method certificate.

This method arranges a mining V-shaped headframe at the shaft collar, a hoisting system, and a group of suspension winches for facilities, effectively ensuring construction safety inside the tunnel. Advanced umbrella drilling technology is adopted in the shaft, accelerating construction speed, reducing safety risks of in-tunnel construction, and lowering labor and time costs.

In the hoisting field, through modification of the auxiliary hoist, a manned hoisting cage was added as a passage for personnel to go up and down and as an emergency evacuation channel, along with rope breakage prevention measures, effectively solving problems of the traditional manned system such as large swaying amplitude and slow operating speed, improving safety and reliability, reducing human unsafe factors, and helping to build standardized safe construction. At the same time, a manual winch hoisting system is configured as a backup hoisting device to ensure that personnel can safely evacuate from the shaft in the event of a power outage or generator failure, erecting a strong barrier under emergency conditions.

The Guangdong Zhaoqing Langjiang Pumped Storage Power Station is a key project of China's medium- and long-term pumped storage development plan for the 14th Five-Year Plan period and one of the first major technical demonstration and application projects for variable-speed pumped storage units. The station is planned to have an installed capacity of 1.2 million kilowatts, with four 300,000-kilowatt units planned for installation, one of which is a variable-speed pumped storage unit independently developed by China. Once completed, it will effectively ease the peak-shaving pressure on the Greater Bay Area power grid and promote the safe and stable operation of the Greater Bay Area's power system.