Study on Key Technology of High Cutting Coal Mining Face with Annual Coal Production of 14 Million Tons

In view of production experiences on a high cutting coal mining face with an annual coal production of 14 million t in a shallow depth seam of Shendong Mining Area, based on the analysis on geological conditions of the coal mining face, the paper introduced the gateway layout of a high cutting coal mining face and the equipment matched condition and had a study on the roof strata control, gateway support, terminal mining cut- through, two face end vertical transition, control of gatew ay floor heave, coal wall spalling prevention and other key technologies of the high cutting coal mining face. The results showed that during the terminal mining period, with an optimization made on the steel mesh paving technique, a steel mesh paving time at the terminal mining of the high cutting coal mining face was reduced from 7 days to 2.5 days. After the vertical transition applied to the two face ends of the high cutting coal mining face, about 1. 2million tons coal additionally were mined from a single coal mining face and a coal mining recovery rate was improved by about 2%. With a pilot floor dinting + premade concrete block + intensive single props + side wall reinforcement combined floor control techniques applied, an advancing rate of the coal mining face at the floor heave section was increased by 10 times. With a se ries of key technology applied, a safety and high efficient mining of the coal mining face could be ensured and the target of the annual production of 14 million t per sing le coal mining face could be realized.