近年来硬质煤层比例不断上升，传统机械截割方法在硬煤条件下的效率低下一直是我国煤炭生产行业的攻坚难题，寻求一种对硬质煤层具有强适用性的破碎方法成为煤矿智能化建设的重要科学问题。冲击与截割协同破煤技术是一种新型硬煤开采方式，其通过利用截齿在运动切线方向上的往复冲击使煤体内部产生破坏，降低硬煤开采难度。而考虑到截齿冲击的时空差异可能对破煤性能产生影响，将冲击截齿应用至采煤机滚筒，设计了具有截齿冲击功能的采煤机改造结构，基于该结构建立了不同截齿冲击时空关系的运动模型，并利用离散元方法分析了不同冲击时空关系的滚筒破煤特性，模拟结果表明，同步冲击方式在各硬度下的破煤效率均优于异步冲击的破煤效率，滚筒受力均值与峰值均低于异步冲击，且相对异步冲击更稳定；此外同步冲击在各硬度下的破煤性能相对传统滚筒均有较大提升，2种方式下的破煤效率差距最大接近24%，滚筒受力差距最大达到60 kN。为测试冲击与截割协同破煤技术的实际性能，设计了简化试验装置，开展了井下破煤测试，测试结果表明，截齿冲击与未冲击状态下的平均截割阻力分别为4 473,5 390 N，截齿冲击较未冲击时可降低截割阻力约17.22%以上，所得结果虽与模拟结果有偏差，但综合截割机构减小、煤体硬度减小因素，仍可认为冲击与截割协同破煤的实际性能取得了理想效果，并体现了冲击与截割协同破煤对坚固性系数煤层的有效性，同时也可以认为截割载荷降低程度的变化规律与模拟所得变化规律相似，验证了同步冲击时空关系对硬煤具有更高适用性的结论。

The proportion of hard coal seams has been increasing in recent years. The low efficiency of traditional mechanical cutting methods under hard coal has always been a problem for the China’s coal industry. Therefore, a crushing method with strong applicability to hard coal is required, which has become an important scientific issue for the intelligent modernization of coal mines. Impacting cutting technique is a new type of hard coal mining method. The reciprocating impact of picks in the tangential direction of movement is used for the destruction of coal, and the difficulty of hard coal mining is reduced. However, the coal crushing performance may be affected by the time and space difference of picks impact. In this study, the impact picks were applied to the shearer drum, and the modified structure of the shearer with picks impact function was designed. The different motion models of the impact time and space of picks were established based on the drum structure. Also the coal crushing properties of the drum with different impact time and space relationships were analyzed using discrete element method. The simulation results show that the coal crushing efficiency of the synchronous impact method is better than that of the asynchronous impact under each scheme. The average and peak force of the drum are lower than that of the asynchronous impact, and it is more stable than the asynchronous impact. In addition, the coal crushing performance of synchronous impact under each scheme has been improved compared with traditional drum. The maximum difference in coal crushing efficiency between the two methods is close to 24%, and the maximum difference in drum force is up to 60 kN. In order to test the actual performance of the coal crushing in conjunction with impacting cutting technique, a simplified test device was designed, and the coal crushing test was carried out. The test results show that the average cutting resistance of the picks under impact and un impacted states are 4 473 N and 5 390 N. The impact of picks can reduce the cutting resistance by more than 17.22% compared with the un impacted state. Although the results obtained were deviated from the simulation results, the reduction of the comprehensive cutting mechanism and the reduction of hardness of coal could still be considered as that the actual performance of coal breaking by impact and cutting synergistic had achieved an ideal effect. The effectiveness of coal crushing with impacting cutting technique on hard coal seams was reflected. Meanwhile, it could be considered that the change law of cutting load reduction was similar to the change law obtained by simulation, which verified the conclusion that the time space relationship of synchronous shock had higher applicability to hard coal.

1 不同冲击时空关系的滚筒运动轨迹分析

   1.1 冲击与截割协同破煤滚筒的结构设计

   1.2 不同冲击时空关系下的滚筒运动模型

   1.3 滚筒运动模型的数值拟合分析

2 不同冲击时空关系的煤体破碎特性分析

   2.1 离散元本构关系

   2.2 滚筒破煤的离散元模型

   2.3 不同冲击时空关系的破碎特性分析

   2.4 同步冲击与传统滚筒的破煤特性对比

3 冲击与截割协同破煤的实际性能测试

   3.1 试验装置设计

   3.2 测试结果分析

4 结论