基于在神东柳塔煤矿实际使用的两柱掩护式放顶煤支架的立柱和平衡千斤顶工作阻力观测,分析了ZFY10200/25/42型两柱掩护式放顶煤支架的理论支撑效率为83.1%,而在实际使用过程中,由于平衡千斤顶常处于受拉的不合理工作状态,大幅降低了支架支撑效率,该支架在08综放工作面的实际支撑效率仅能达到68.7%。故两柱掩护式放顶煤支架不适用于硬煤层及节理裂隙不发育的中硬煤层放顶煤开采。

Based on the working resistance observation of the leg and the balance jack used in the two leg shield coal caving support applied to Shendong Liuta Mi ne, the theoretical support efficiency of the ZFY10200/25/42 type two leg shield coal caving support was analyzed as 83. 1%.During the actual application, due to the te nsion of the balance jack often in an irrational work condition, the support efficiency of the powered support would be highly reduced and the actual support efficiency of the powered support applied in No.08 fully mechanized top coal caving mining face only reached 68.7%.The paper held that the two leg shield caving powered support would not be suitable for the top coal caving mining in the hard coal seam and the joint crack undeveloped medium hard seam.