Recently, After 8 months and 265 times of scientific research and experiments, Wuhan Heavy Duty Machine Tool Group Corporation Co., Ltd. (WuZhong) of China North Industries Group Corporation Limited (NORINCO GROUP) designed and manufactured the friction stir welding system and then completed the first combined welding of the ring at the bottom of the container with a diameter of 9.5 meters in China. The storage tank is used to store the kinetic fuel of launch vehicle and its location and welding technology is very important. This project marked the international leading level of intelligent welding equipment in WZG successfully developed. Among them, the assembly welding of the bottom of the box is one of the difficulties of the whole storage box. The welding seam includes the longitudinal welding between the melon and the melon, the circular welding between the melon ellipsoid and the fork ring and the top cover, and the circular welding of the manhole flange and the filling flange on the surface of the box bottom. Aiming at the development of heavy rocket tank bottom, WuZhong has designed and manufactured a friction stir welding system for the bottom of 10-meter tank according to the needs of users. After years of design and manufacturing work, WuZhong solved a series of technological problems to meet the needs of users and filled the gap in the field of extra-large diameter storage tank products in China.