Due to lack of maintenance, the bearings were not lubricated with oil for a long time, resulting in damage to the No.1 axle and the No.2 rim. The edge of the No.1 rim has slight deformation, while the solid tire is undamaged. Custom rims and replaced. The old solid tire was retained. Considering that the No.1 rim is subjected to greater external force, after evaluation, the No.1 and No.2 rim were swapped and installed without increasing the repair cost.