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　　On March 3, China’s first exported large-diameter dual-mode shield machine “CREC 749,” developed by China Railway Engineering Equipment Group, a subsidiary of China Railway High Tech Industry Co., Ltd., started excavation, marking that the Cefalù railway tunnel project in Italy officially entered the shield construction stage.

　　The Cefalù railway tunnel is a single-line double-hole tunnel, with a length of 6.7 kilometers, a maximum buried depth of about 300 meters and a maximum water pressure of over five bar. The stratum is mainly composed of silty sandstone and quartz sandstone, and the tunnel passes through several historical and cultural sites, posing high requirements for construction equipment and technology.

　　"CREC 749", with an excavation diameter of 9.98 meters, is China’s first large-diameter dual-mode shield machine exported overseas. After it arrived at the project site on September 3, 2021, China Railway Engineering Equipment Group organized a professional technical service team composed of local employees and Chinese technicians, which assembled and debugged the equipment in strict accordance with engineering schedule, thus efficiently accomplishing all tasks and paving the way for the operation of the shield machine.