I can't. The roundness of the circular tube is ensured by controlling the production process, equipment precision, material quality, manufacturing process and storage protection. Thermal deformation and stress will occur in the welding process, which will lead to the change of the shape of the circular tube. In addition, welding defects, such as porosity, slag inclusion, incomplete fusion, etc., will occur during welding operation. These defects will also affect the roundness of the circular tube.