On August 15th, at construction site of the Pingjiang pumping storage power station in Pingjiang, Hunan, world's first variable diameter oblique well excavation "Tianyue" independently developed by China was successfully launched.

It has 50 -degree large income climbing, 6.53 meters to 8 meters of variable diameter excavation.

http://hn.people.com.cn/BIG5/n2/2023/0816/c336521-40533479.html