August 17，By China Railway Construction Heavy Industries、China Railway 14th Bureau、Large-diameter slurry balance shield machine jointly built by Guangzhou Railway Group“The Sakashima”It started smoothly at the construction site of Shantou Bay Tunnel of Guangzhou-Macao Port Railway.，It marks that the first passenger and freight railway submarine tunnel project in China has formally entered the stage of shield tunneling.。

“The Sakashima”Departure site

The shield section of Shantou Bay Tunnel of Guangzhou-Macao Port Railway is 2990 meters long.，It mainly crosses the soil layer、Rock formation、Uneven hardness and fault zone，And under the Bay Tunnel.，Sea water pressure is high，High risk of shield tunneling，Cutter change operation for pressure belt feeding、High requirements for sealing configuration of shield machine。

For large diameter of this project、High water pressure、Long downhill、Strong corrosion and other construction difficulties，The R & D team of China Railway Construction Heavy Industry is“The Sakashima”A series of targeted designs were carried out.，Pressurized composite cutter head with new material、Telescopic main drive、Visual system of excavation bin、Automatic measurement monitoring、Many innovative technologies such as online perception of tool status，O as to ensure the safety of the shield machine.、Fast tunneling。

“The Sakashima”Off-line in the acceptance of Railway Construction Heavy Industry

“The Sakashima”Excavation diameter of shield machine 13.42 meters，The total length is 126 meters，The weight of the whole machine is about 3300 tons.，Total installed power 9300 kW。Since the shield machine entered the site for assembly，Research and development of China Railway Construction Heavy Industry、The service team always sticks to their posts.、Overcome difficulties，Timely response to customer needs，It provides a solid guarantee for the smooth start of the shield machine.。 

It is reported that，Guangzhou-Macao Port Area Railway is a key construction project in Guangdong Province.，After completion, it will help Shantou Port to expand its northward radiation depth.，Provide convenient access to the sea for surrounding provinces and cities，At the same time, it also provides convenient conditions for efficient collection and distribution of regional material elements.，It is of great significance to build a modern port city along the southeast coast.。