Assessment on outburst danger before mining operation of No.3115 coal mining in Qinchi Mine

Base on the systematic collections on the gas pre-drainage information of the No.3115 coal mining face in Qinchi Mine,the gas outburst prediction information of the air retuning gateway and the air income gateway and the related parameters from the tests of 5 coal samples,the assessment on the outburst danger of the coal mining face was made individually with the unit index,comprehensive index method and remnant gas content method.The calculation on the gas drainage quantity and the gas drainage rate from the coal mining face showed that the gas outburst danger was eliminated for the proposed No.3115 coal mining face.