镐型截齿截割煤岩过程的截割力研究

摘要

为探究镐型截齿截割煤岩过程中截割力的变化及其影响因素,以Evans镐型截齿直线截割力模型为基础,提出了镐型截齿旋转截割力模型;利用滚筒采煤机镐型截齿截割煤岩轨迹表达式,推导了镐型截齿截割过程中,截割角及截割厚度变化的表达式;在截割参数范围内,计算出镐型截齿截割角在截割过程中最大变化可达±4°;根据镐型截齿旋转截割力模型,在截割厚度一定的条件下,计算并分析截割力与截割角及半锥角的关系,得出当镐型截齿半锥角为36°时,截割力在截割过程中最大截割厚度前后能够保持平稳变化;将截割角及截割厚度变化计入截割过程中计算截割力,发现影响截割厚度主要因素的牵引速度对截割力影响最大,而角速度与截割半径对截割力的影响依次减小.所得公式与结论可为镐型截齿及采煤机的设计提供理论参考.%To explore the variety and influence factors of cutting force in the process of conical pick cutting coal,a Rotary Cutting Model (RCM) of conical pick was proposed based on the Evans' s linear cutting model.The expressions of the cutting angle and cutting thickness in the process of conical pick cutting coal were deduced on the basis of cutting trajectory of shearer conical pick.Then the possible maximum change of cutting angle was calculated with the cutting parameters range in cutting process,which would reach ±4°.According to the RCM,the relationship between the cutting force and cutting angle,semi-tip angle was obtained under a certain cutting thickness condition.The relationship shows that the cutting force maintains a smooth change before and after the maximum cutting thickness when the semi-tip angle is 36°.Put the cutting angle and cutting thickness in cutting process into the RCM,it showed that the traction speed has the greatest influence on cutting force,and the angular velocity and cutting radius of drum have a less influence.The derived formulas and conclusions can provide a theoretical basis and guidance for the future design of shearer and conical pick.