Recently，Small-diameter small turn jointly built by Railway Construction Heavy Industry and the Fifth Bureau of HydropowerTBM——“Crape Myrtle”The excavation task of drainage tunnel and drainage gallery with a length of 4156 meters has been successfully completed.，It has laid a solid foundation for the main project of Qujiang Pumped Storage Power Station.。

It is reported that，“Crape Myrtle”TBMAbout 80 meters long，The whole machine weighs 230 tons.，Excavation diameter 3.53 meters，Minimum turning radius 30m，It is a typical small-diameter and ultra-small turning radius type.TBM。

Since the start，“Crape Myrtle”TBMCrossing through fault fracture zone with complex surrounding rock，Overcome the small turning radius of 30 meters.、“S”There are many difficulties such as difficulty in turning and tunneling.，It has successfully completed 16 small turning radii of 30 meters.、Four drainage tunnels and drainage galleries of Qujiang Pumped Storage Power Station with a turning radius of 100 metersTBMTunneling construction task，It marks another 30-meter ultra-small turning radius of Tiejian Heavy Industry.TBMSuccessful and extensive application in pumped storage project。

“Crape Myrtle”TBMSuccessful application of，All kinds of projects in Quzhou have been realized.TBMIn use“Zero”A breakthrough。Compared to the traditional“Drilling and blasting method”Construction，“Crape Myrtle”Successfully drain the hole、The construction period of the drainage gallery has been shortened by about two thirds.，It greatly improves the safety and stability of the construction period.，Minimize the impact on the lives of residents around the project site.，It has contributed to the construction of key projects.。