During the operation of the ?4.2m×13m cement sliding shoe mill discharge end cylinder, there were abnormal situations such as spraying dust. Upon inspection, it was found that the cement sliding shoe discharge end cylinder was worn and perforated, and a large amount of dust entered the lubrication system of the sliding shoe from the perforation. After analyzing the reasons and comparing multiple plans, based on the actual production situation, a repair plan was selected to repair and strengthen the protective plate of the cylinder. After implementing this plan, the repair construction was completed within 3 days (24-hour operation). After the repair of the mill cylinder, the strength of the cylinder was strengthened, and the insulation and deformation prevention of the cylinder were achieved, achieving the expected repair effect.