Recently, the Long March-5 Y3 rocket blasted off and successfully put the Shijian-20 communications satellite into the pre-selected orbit. Long March-5 (LM-5) is lovingly known as “Fat Five” for its huge size, and 70% of the aluminum on its body was made in Chongqing.

Carrier rocket Long March-5 Y3 blasts off from Wenchang Space Launch Center in south China's Hainan Province, Dec. 27, 2019. (Photo by Xinhua/Yang Guanyu)

LM-5 is the largest carrier rocket with the most substantial takeoff weight, the most significant technical span, and the largest carrying capacity in China. Being developed and produced by Southwest Aluminum (Group) Co., Ltd. (SWA), Aluminum Corporation of China (Chinalco), such materials as the 5-meter-long integral forged aluminum alloy ring and panels were used in the critical parts of LM-5.

Que Jirong, an engineer in charge of the forge of SWA, Chinalco introduced that “Fat Five” is 57 meters long, like a tall building, while the 5-meter-long ring is like the periphery beam that firmly connects all parts of the “building,” playing a supporting and fixing role.

The forging process of the 5-meter-long ring is complicated because the ring must be formed in one piece instead of being made of sections connected using welding or riveting. In the absence of mature experience, SWA started the arduous “long march” of innovation.

Que Jirong added that, at the beginning of the project, the most massive aluminum alloy ring that has been developed by SWA is 3.5 meters long. A 5-meter-long ring requires comprehensive improvement of the forging technology, which is not merely a larger size than a 3.5-meter-long one. To this end, SWA has carried out a lot of technical research, and in the ring preparation process, it has cracked eight new technologies and obtained nine new patents.

In the past over 50 years, besides LM-5, SWA has provided a large number of critical materials to Shenzhou spacecraft, Chang’e satellites, Long March rockets, Tiangong aircraft, Dongfeng missiles, aircraft carriers, warships, and other national key projects.

Source: Shangyou News