Through the cold and hot state tests on the MB type fan mill

the correlation among ventilation volume

mill output

negative pressure of the entrance

pressure of the mill outlet and the promotion pressure head in pure air and air with coal powder states was obtained

and the factors affecting the promotion pressure head of the MB type fan mill were investigated

thus the effects of key indexes such as mill output

ventilation volume and HGI index of the coal on the MB type fan mill's promotion pressure head were obtained. The cold test results show that

with the increase of mill outlet ventilation

the mill entrance resistance decreased

the outlet resistance increased

and the increase of the mill outlet resistance was larger than the decrease of the entrance resistance

so the promotion pressure head of the mill declined. The hot test results show that

the promotion pressure head of the mill increased with the mill outlet ventilation

and the negative effect of the mill output on the promotion pressure head was greater than the results calculated by current calculation method. The ventilation and grinding characteristics of the MB type fan mill has great difference but with a certain similarity with that of the S type fan mill. The conclusion can provide technical reference for design and operation of the MB type mill.