This gearbox is used in a new carbon dioxide energy storage project. The gearbox is a multi-shaft output structure with an output power of 11MW, a pitch circle velocity of 138.5m/s, and a large gear diameter of about 2m. It requires high processing accuracy and belongs to the category of high-precision large thin-walled gear, with high processing difficulty. This gearbox, both in design and manufacturing, has reached advanced domestic levels, laying the foundation for the localization of multi-shaft gear compressors or expanders.