Abstract:Aiming at corrosion,low efficiency, more troubles, irregular running of the old fan, further influencing the ventilation and operation of mine, the author puts forward and implements a modification plan, i. e, a set of new main fan was added on the surface site of upcast shaft collar, which composited by itself into system and was alternatively used with old fan each other Essentially, this technical modification made the ventilating condition of mine to be improved.