Directing against state of affairs at present

such as margin of typeselection parameters being selected comparatively large during design stage of air fans for boilers in thermal power plants

the opening degree of air fans in operation being often smaller (for adjustment of inlet regulator) or operation at lower revolution speed (for speedregulating operation mode)

and efficiency of air fans being lower etc.

factors and corresponding measures having to pay attention in margin selection of air fan’s parameters have been put forward through analysing practical example of retrofitting forced draft fans in one power plant

playing certain positive role for energysaving and benefitincreasing in power plants.