Study On Top Caving Coal Mining Optimized Parameter

At first, the paper predict developing history foreground advantages and comingshorts as well as a few kinds of modes of top caving coal in our country . The nucleus part of the article is optimizing top caving parameters and computer simulation analyse , aim at caving step interval , increase the recovery rate , caving coal mode being theorically analysed , carry out calculating methods of numerical value , building up methods and steps of determin nature and fix quanlity , According to move of top coal , provide caculate method of ellipsiod and put forward method of reduce refuse content:(1) Choose reasonable caving interval, when caving step interval is short, refuse content is serious, recovery is lower.(2) Shaft along two neibour orifice approximate equal to short shaft(3) Especial thick coal seam first mine top coal seam ,then mine bottom seam.(4) Rock in coal seam,suggest casting away sub-level caving.The reasonable drawing step interval will make coal -rock face dropping averagely, the triangle loss is smallest and the refuse content is lowest, draw conclusion:(1) Reasonable drawing step intervals would infect rate of refuse content and recovery rate, .reasonable drawing step interval make the coal-rock face droping averagely.(2)When average thickness of seam is 6 meters, the mining and caving rate is 1:1 .The way which cave once per one reamer is advocateted,while two side of woking face are in hollow area,adopting the way of caving once per one reame.(3)Caving coal interval is as interger mutiple as web of winning machine,commonly use drawing top coal once per reamer,or once per two reamer once per three reamer,for winning machine of cylinder type,caving coal interval chang between 0.5-1.5m and 0.6-1.8m,low mining and caving coal and thickness of coal seam is less than 8m,usually use drawing top coal once per one reamer. When coal seam thickness is bigger,use drawing top coal once per two reamer;for high drawing opening position and middle drawing opening position,when caving coal interval equal to projective of orifice ,usually use once per two reamer,projective length of single orific is too long and working permit ,it may use drawing top coal once per...