Cutting mechanism of conical pick based on elastic-plastic-fracture theory and test verification
WANG Xin1, XU Lanxin2, CHEN Hongyue3,4, BAI Yangxi3, CHEN Hongyan3
1. Research Institute of Technology and Equipment for the Exploitation and Utilization of Mineral Resources, Liaoning Technical University, Fuxin 123000, China;
2. College of Management, Xi’an University of Science and Technology, Xi’an 710054, China;
3. College of Mechanical Engineering, Liaoning Technical University, Fuxin 123000, China;
4. China National Coal Association, Dynamic Research for high-end complete Integrated Coal Mining Equipment and Big Data Analysis Center, Fuxin 123000, China
Abstract：To study the cutting mechanism of conical pick in process of cutting coal, a mathematical model of external contour of conical pick was established. Based on theories of elastic mechanics, plastic mechanics and fracture mechanics, the theoretical model for elastic-plastic-fracture instability to happen under action of cutting force of pick cutting coal rock was proposed to describe the mechanism of pick cutting coal rock. According to the model, expressions for pick cutting force and coal rock stress under coal rock’s elastic deformation, plastic deformation and fracture instability were derived. Finally, the self-built test equipment was used to perform pick cutting coal rock tests with different cutting angles. The test results showed that during pick cutting force being exerted on coal rock, the contact area between pick and coal rock gradually increases with increase in pick cutting depth, coal rock has elastic deformation stage, plastic deformation one and fracture instability one, and these facts are consistent with what the theoretical model describes; when cutting angle is 90°, 75°, 60°, RMS errors between the theoretical value and the test one of pick cutting resistance are 0.082 kN, 0.199 kN and 0.204 kN, respectively, the difference between the theoretical value and the test one is small to verify the correctness of the theoretical model.
王鑫1,徐兰欣2,陈洪月3,4,白杨溪3,陈洪岩3. 基于弹-塑-断裂理论的镐型截齿截割机理研究与实验验证[J]. 振动与冲击, 2021, 40(3): 165-171.
WANG Xin1, XU Lanxin2, CHEN Hongyue3,4, BAI Yangxi3, CHEN Hongyan3. Cutting mechanism of conical pick based on elastic-plastic-fracture theory and test verification. JOURNAL OF VIBRATION AND SHOCK, 2021, 40(3): 165-171.
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