这项技术，中国落后世界百年，却用20年完成逆袭！

北京有多大呢？有10个伦敦那么大。

从老舍笔下的四九城，到如今的环京城市群，这座庞大的巨型城市，承载了2000多万人的生活。

为了运载庞大的人口，北京地铁已经修到22号线。这条线路也是北京第一条跨省地铁，建成后，从燕郊到北京市中心只需半小时。

To transport the vast population of Beijing, the subway of the city has been extended. 

Few people know that underground construction requires strong support from the manufacturing industry. The reason why Beijing's subway can advance rapidly is closely tied to a super equipment, tunnel boring machine.

很少有人知道，修地铁需要强大的制造业支撑。北京地下轨道交通之所以能高速进击，背后离不开一个超级装备。

中国为了掌握这项技术，走了很长的路。

In the 19th century, London's Thames River was as congested as the city's roads are today. The river was London's economic lifeline, but also a major barrier to traffic. The city urgently needed more options.

Miners dug out soft earth and moved the shield forward. Bricklayers worked behind the shield to build the tunnel and the arches with bricks and cement.

The tunnel boring machine differs from an excavator because it tackles two fundamental issues: first, where to dispose of the excavated soil, and second, preventing the tunnel from collapsing once it's been dug.

Before 2008, China relied on imported tunnel boring machines, facing work stoppages and high costs due to a lack of domestic development. With over 60% of global demand for these machines driven by crucial infrastructure projects, China's need for a self-sufficient solution became apparent.

China's diverse terrain includes rich water zones in the southeast, soft soil in the central plains, and hard rock in the southwest.

Domestic tunnel boring machines are customized for these conditions, showcasing flexibility in softer areas and strength in tougher terrains, effectively overcoming diverse geological challenges.

Beijing's vast transportation network accommodates its large population, and China's underground steel legion embodies inclusivity in the city's spirit. This convenience and security are now spreading to more countries as China opens up.