Development and Application of Crawler Walking Type Hydraulic Powered Support Used for Short-Wall Mining

In order to improve the coal mining recovery rate and production efficiency and to eliminate the danger of a suspended roof with a large area, a ZX7000/ 17/30 mode crawler walking type hydraulic powered support in thin seam was researched and developed for a temporary and reinforced support of the roof above the W orking space of the gateway.The paper introduced the realization of the supporting, walking, control system and other key technology of the powered support.A FLAC3D finite difference program was applied to establish a 3D numerical model of the shortwall mining face and analyze the support function of the powered walking support af fected to the roof of the shortwall mining face and coal pillar stability.The analysis results showed that when the powered walking support applied to support the roof of t he coal mining face, the vertical stress of the protective coal pillar in the connection gateway was reduced by 40%，the range of the coal pillar plastic zone was reduce d, the vertical stress of the coal pillar between the mining face and gateway was reduced by 45%, the width of coal pillar between the mining face and gateway was red uced from 1.2 m to 0.8 m, the roof falling line could be effectively controlled in the goaf behind the coal mining face, the mining scope of coal pillar could be enlarged, th e gateway driving length per 10 000 t coal could be reduced about 220 m, the month production value of the coal miming face could be about 60 00080 000 t and the Co al mining recovery rate was improved from previous 60% to over 80%.