Before welding, the galvanized layer on the surface of the welding part can be removed by grinding, which can ensure the quality of the weld. Pay attention to the anti-rust treatment of weld after welding. It is suggested to use special repair coating for hot dip galvanizing, which can not only repair the hot dip galvanized weld, but also be directly applied to the surface of hot dip galvanized layer without falling off. The special repair coating for hot dip galvanizing must meet the requirement that the zinc powder content is higher than 90%.