HIT's "hardcore" technology helps the "Ruixue Spring" Winter Olympics train debut

"Ruixue Welcomes Spring" front cover

Life News (reporter Lv Xiaoyan) On the 6th, the Beijing Winter Olympics train painted with "Ruixue Yingchun" appeared on the Beijing-Zhang high-speed railway, and the main line of the Beijing-Zhang high-speed rail intelligent EMU was 174 kilometers long, realizing the world's first 350km/h fully automatic driving, which is an intelligent upgraded version of the Fuxing and realizing the wish of "sitting on the high-speed rail to watch the Winter Olympics". It is reported that the skin of the two locomotives of the Beijing-Zhang high-speed railway, "Dragon and Phoenix Chengxiang" and "Ruixue Yingchun", is the team of Professor Wang Guofeng of the School of Materials of Hitachi University of Technology using a rapid superplastic molding process to help achieve manufacturing and production.

"Dragon Phoenix Chengxiang" and "Ruixue Yingchun" adopt bionic and aerodynamic principles, and are imitated in "Eagle Falcon" and "Sailfish" respectively. Its streamlined bionic locomotive model can effectively reduce gas shunting, reduce air resistance, reduce internal consumption, and ensure speed. At the same time, this also increases the difficulty of manufacturing and producing front skins.

The difficulty in forming the front of the "Ruixue Yingchun" vehicle lies in the connection between the skin of the plate and the skin of the lower wall panel. The total length of the connecting plate skin is 11 meters, which is composed of a double prismatic line of the complex curved space shape; the lower wall plate skin is 11 meters long, the product shape is composed of a profile with a large change in curvature, the ridge rounded corners are obvious, the blank is not a simple plate, but an open profile with multiple T-shaped reinforcements, after forming, it is not only necessary to ensure the accuracy of the outer surface shape, but also to ensure the position accuracy of each T-shaped reinforcement, which is extremely difficult to form.

Using the traditional stretching process, only simple curved shapes with large rounded corners can be formed, and sharp edges cannot be formed. Professor Wang Guofeng's team adopted the rapid superplastic forming process to break through the above difficulties and realize the first piece inspection of the front skin of the "Ruixue Yingchun" in June 2021, controlling the forming accuracy of the complex space surface with a total length of 11 meters within the range of 1.5 mm, and forming the sharp edge according to the design requirements of CRRC Group manufacturers. Recently, the first inspection of the "Dragon Phoenix Chengxiang" front skin has been completed.

Image courtesy of HIT

【Source: Life Daily】