截割角和截割线速度对镐型截齿截割性能的影响

Cutting angler and cutting linear velocity affected to cutting performances of pick-shaped cutter

为深入研究截割角和截割线速度对截镐型齿截割性能的影响,运用PFC^(3D)离散元软件建立镐型截齿与煤壁模型,将切削厚度恒定为10 mm,截割距离为20 mm,对不同截割角与截割线速度进行直线截割仿真,对煤壁内部的微破坏、截齿载荷以及截割比能耗进行分析。结果表明,截割线速度越大,对煤体的剪切破坏越明显,截割角影响煤壁微破坏程度与裂纹扩展方向;随着截割线速度的增大,截割阻力均值与截割比能耗均呈先减小后增大的趋势;截割角为40°时截割阻力均值明显较大,但截割比能耗较小,与50°接近;截割角为55°时截割阻力均值较小,但截割比能耗明显较大,截割效率低。综合考虑,截割线速度应取3~4 m/s,截割角应取45°~50°为宜。

In order to deeply study the cutting angle and cutting linear velocity affected to the cutting performances of the pick-shaped cutter,a PFC3 Ddiscrete element software was applied to establish the pick-shaped cutter and coal wall model. A cutting depth was fixed as 10 mm and the cutting distance was 20 mm. A straight-line cutting simulation was conducted with the different cutting angle and cutting linear velocity. An analysis was conducted on the micro damage within the coal wall,cutter load and the specific energy consumption of the cutting. The results showed the higher cutting linear velocity,the more obvious cutting damage would be to the coal seam and the cutting angle would be affected to the micro damage degree of the coal wall and the cracking expansion direction. With the cutting linear velocity increased,the average value of the cutting resistance and the specific energy consumption of the cutting would be in a tendency with a reduction first and a increasing late. When the cutting angle was 40°,the average value of the cutting resistance would be high obviously,but the specific energy consumption of the cutting would be low and would be closed to 50°. When the cutting angle was 55°,the average value of the cutting resistance would be low,but the specific energy consumption of the cutting would be high obviously and the cutting efficiency would be low. In a comprehensive consideration,the cutting linear velocity should be 3 - 4 m/s and the cutting angle should be 45° - 50° possibly.