At the entrance of the CREG shield assembly workshop, a blue and white shield machine cutter head with a diameter of nearly three stories is being hoisted onto a heavy-duty transport truck. Soon, it will be put into work on the Tel Aviv subway tunnel project in Israel. And this is the 8th shield machine that CREG has exported to Israel in recent years. In addition to Israel, the company's shield equipment exported to Austria, Italy, Portugal, Qatar and other countries has also been rolled off the assembly line and installed...

Wang Dujuan, chief expert and deputy general manager of China Railway Engineering Equipment Group, said that in the past, underground tunnels used to be a difficult point in the construction of many major projects. Traditional excavation and excavation relied on methods such as pneumatic drilling, blasting, and gravel slag, and the safety and efficiency were very low.

In order to speed up infrastructure construction, in the 1990s, China imported two hard rock boring machines from abroad at a cost of 700 million yuan for the construction of the Qinling Tunnel on the Xikang Railway. But these imported machines are not only expensive, but also more expensive for follow-up services.

Wang Dujuan and her colleagues had a dream in their hearts: they must build their own shield machine! Afterwards, she and her colleagues conducted repeated investigations, repeated attempts, and over and over again. In April 2008, she finally successfully developed China's first composite earth pressure balance shield machine with independent intellectual property rights. The prototype was subsequently applied to the Tianjin subway project, which not only had a fast excavation speed, but also controlled the surface settlement to within 3 mm. After the victory in the first battle, this meritorious shield machine was officially named "China Railway No. 1".

After the domestic shield machine has achieved a breakthrough from nothing, it is inseparable from the continuous innovation of technology if it wants to continue to achieve from existence to strength and rank among the forefront of the world. In terms of intelligent product innovation, the traditional tunnel boring machine construction operation is to dig horizontally, but when excavating a well, for example, the tunnel boring machine needs to dig vertically. In order to meet the needs of vertical digging, CREG has carried out another ten years of scientific research.

In recent years, the tunnel boring machine produced by CREG is becoming a new domestic product in the Belt and Road Initiative.Editor/Ma Xue