【摘要】 冲击破碎速度是影响煤块冲击破碎效果的主要参数。基于分段塑变碰撞模型得到煤块与冲击板碰撞时的接触应力,并结合裂缝假说和能量守恒原理推导出煤块被破碎到指定粒度需要的理论冲击速度。进行煤块冲击破碎试验,通过试验数据分析得到了冲击破碎速度的试验拟合公式和理论修正公式。88%的拟合计算值与试验值的误差小于10%,但拟合公式结构复杂,不适合工程应用;85%的理论修正值与试验值的误差小于20%,满足初级破碎所需的精度,可以作为初级破碎时冲击破碎速度的理论选择依据。更多还原

【Abstract】 Impact-crushing velocity is the main parameter influencing impact-crushing effect of lump coal.Here,when lump coal impacted a rigid plate,the contact stress was obtained based on a piecewise plastic deformation model.The impact velocity crushing lump coal into a certain size was derived theoretically with crack hypothesis and energy conservation principle.The test fitting formula and for impact-crushing velocity the theoretical modified formula were gained through lump-coal impact-crushing experiments and test data analysis.The errors between 88% results calculated with the test fitting formula and the test data were less than 10%,while those between 85% results calculated with the theoretical midified one and the test data were less than 20%.The analysis showed that the fitting formula is complex and not suitable to engineering application,the theoretical modified formula can meet the accuracy requirement for primary crushing and may be a theoretical choosing rule for impact-crushing velocity.更多还原