This paper introduces the concrete practicing scope and targets of t he technical transformation of the frequency control system of the winch in auxi liary blind incline shaft, and in the light of the problems existing in actual w ork, expounds the principles, features and key techniques of the transformation of the frequency control system.

Based on the characteristics of cruts of blind incline shafts of Q ianqiu mine and the affect of mining on the blind incline shafts, the 1st and 2n d major maintenances performed using yielding metal support and bolting and shot creting wire mesh by the effect of their safety pillar's abutment pressure are d escribed.