In order to solve the problem of high air leakage in air preheaters

the actual operation situation of different air preheater sealing forms was studied. The effects of inspection and maintenance level and unit capacity level on the sealing effect were discussed. The problems that are easy to occur after technical transformation of the air preheater were summarized

and countermeasures were proposed. The results show that

the adjustable seal has the best application effect

then is the flexible seal

and the fixed seal has the worst application effect. The air leakage compliance rate of the turbine-generator unit gradually decreased as the number of turbine-generator units increased in a thermal power plant. The turbine-generator unit capacity level can affect the sealing effect of different sealing forms. Units with different capacity levels are suitable for different sealing types.