The paper describes the characteristic for three cylinder tandem compound four exhaust air-cooling condensing reheat turbine by DFSTW,the effect of air-cooling system application to steam turbine structure is analyzed as well as the measures taken in period of air-cooling steam turbine design.

On the basis of summary of sub-critical air-cooled unit construction, and combined with current super-critical air-cooled power plant construction, this paper brings forth the idea of standardization of air-cooled units, and the definition of air-cooled turbine power and determination of its back pressure.