China’s largest domestically developed shield tunneling machine rolled off the production line on September 15 in Zhengzhou, the capital of Central China’s Henan Province.
The machine was developed by China Railway Tunnel Group Co., Ltd., China Railway No.4 Engineering Group Co, Ltd, and China Railway Engineering Equipment Group, which are all subsidiaries of China Railway Group Limited.
The ultra-large slurry balance shield machine, named Zhongtie 1662, has a designed excavation diameter of 16.68 meters, measures 125 meters in length and weighs about 4,800 metric tons.
Zhongtie 1662, an ultra-large slurry balance shield machine, rolls off the production line in Zhengzhou, the capital of Central China’s Henan Province, on September 15. [Photo/sasac.gov.cn]
The machine will be used to build a tunnel beneath a reservoir in Hefei, the capital of East China’s Anhui Province. The 2.9-kilometer tunnel will have a two-bore, two-level design, passing through a large-scale dual-purpose reservoir for flood control and water supply. Complicated working conditions pose extremely strict requirements for the precision of controlling and adjusting the machine.
The shield machine adopts a full-face, constant-pressure cutter-head, achieving cutter replacement under constant pressure in an eight-bar high-pressure environment, and balancing efficient construction with operational safety.
It features a circulating slurry discharge system that adopts the industry-leading ‘screw conveyor direct discharge + out-of-chamber crushing’ slurry treatment mode. This ensures efficient discharge by the slurry pump and avoids the operational risk of entering the chamber to repair the crusher, thereby building a solid safety defense line for underwater tunnel construction.
(Executive editor: Zuo Shihan)
