Recently, the first domestic variable-diameter reaming shaft boring machine in China, developed under the leadership of Huadong Engineering Corporation (HDEC), successfully completed the excavation of a 358-meter-deep exhaust ventilation shaft at the Yongjia Pumped Storage Power Station in Zhejiang, reaching the predetermined position. During the process, the maximum daily excavation reached 16.8 meters, setting a new world record for the daily advance of a shaft boring machine and marking that China's mechanized construction of deep and large shafts has reached an internationally leading level.

The Yongjia Pumped Storage Power Station in Zhejiang, invested in and controlled by HDEC as the general contractor, is a key implementation project of Zhejiang Province's 14th Five-Year Plan, with a total installed capacity of 1.2 million kilowatts. The "Zhumeng" (Dream Chasing) machine has an excavation diameter range of 6.5 to 8.0 meters and undertakes the excavation tasks of the exhaust ventilation shaft, two headrace upper shafts, and the surge shaft of the Yongjia Pumped Storage Power Station, with a total excavation volume expected to reach 1,334 meters, realizing the first application of a variable-diameter reaming shaft boring machine in ultra-deep and large-diameter shaft construction in China's pumped storage field.

The main machine weighs about 270 tons and the complete machine is 27 meters tall (equivalent to the height of a 9-story building). It integrates 23 innovative technologies and can adapt to precise reaming excavation under complex geological conditions, pioneering intelligent shaft excavation in China. It is equipped with a real-time cutter condition monitoring system, a main drive vibration monitoring system, and the SBE intelligent auxiliary excavation system. A smart management and control system for shaft boring machine construction has been developed, enabling functions such as real-time rock formation analysis, dynamic optimization of excavation parameters, machine status monitoring, and process control. The team pioneered the construction method of "directional drilling + raise boring + reaming shaft boring machine," deeply integrating traditional shaft construction with full-face tunnel boring technology and innovatively achieving simultaneous operation of multiple processes including excavation, support, mucking, and guidance, bringing the excavation quality of the water conveyance system of the Yongjia Pumped Storage Power Station to the industry's top level.

Since the equipment was launched on November 20, 2024, the "Zhumeng" machine has cumulatively excavated 325.5 meters, with a fastest single-day advance of 16.8 meters. Its construction efficiency is 3 to 5 times higher than that of the traditional drill-and-blast method, setting a world record for the daily advance of a shaft boring machine. At the same time, the number of personnel at the deep shaft working face has been reduced by 70%, ensuring the intrinsic safety of ultra-deep and large-diameter shaft construction.

With the scheduled completion of the exhaust ventilation shaft, the "Zhumeng" machine will move on to the excavation of No. 1 and No. 2 headrace shafts of the upper reservoir of the pumped storage power station. The successful development and application of the equipment provide a vivid example for the comprehensive mechanized and intelligent transformation of pumped storage power station construction, and also provide a brand-new construction method and equipment for the construction of deep and large shafts in subsequent fields such as water conservancy, mining, and transportation.

China's first variable-diameter reaming shaft boring machine, the "Zhumeng"