This article analyzes the problems of overheating in waste heat boilers, such as Increased boiler pressure can easily cause explosions, deformation of metal components may lead to collapse accidents, the decrease in pressure bearing capacity of pressure bearing components can easily cause problems such as pipe bursts or leaks. Taking the grate cooler as the object, the equation for thermal equilibrium was listed, and the reasons for the overheating of the waste heat boiler were analyzed; It is proposed to increase the air volume of the high-temperature section of the grate cooler, increase the air volume of the second and third air, reasonably control the grate speed of the grate cooler, reasonably select and maintain the refractory and insulation materials of the waste heat boiler, upgrade the materials of pressure bearing components, add waste gas pipelines and steam pipeline temperature reducing devices, and regularly conduct metallographic and non-destructive inspections of steel components and other safety measures. To avoid overheating of the waste heat boiler from the source, it is necessary to reasonably regulate the firing process, configure the air supply at the head and tail of the cement kiln, stabilize the firing system working conditions, ensure stable operation of the waste heat boiler under safe working conditions, and extend its service life.