Abstract: Aiming at the problem of variable load of scraper chain under complex working conditions, the movement of coal granular on scraper conveyor and the stress characteristics of chain link were analyzed. Based on the discrete element method and multibody dynamics method, a DEMMBD (discrete element method and multi body dynamics) scraper conveyor model was established; based on the analysis of the formation of granular flow and coal granular accumulation profile on scraper conveyor, the running resistance and dynamic load of chain link in heavy haul section were further studied; finally, based on the analysis of theoretical analysis and simulation results, the size, variation trend and main influencing factors of contact force of scraper chain link under stable, emergency shutdown and full load start up conditions were explored. The results show that the contact force between the chain links on the side of the coal baffle is greater due to the accumulation of coal granular under the stable condition, and its value is 0.328kN ~122.557kN; under the emergency shutdown condition, the contact force decreases to 0.745kN ~77.602kN due to the decrease of scraper chain speed; under the condition of full load start up, and not at the moment of startup, the contact force value increases abnormally due to the increase of starting speed and the accumulation of coal granular, and the maximum value is 161.328kN. The research results provide a theoretical basis for solving chain sticking or chain breaking of scraper chain under actual working conditions.

Key words:  scraper conveyor; the coupling between rigidbodies and bulks; coal granular; link contact force; complex working conditions
BI Wen-jie, LI Bo, WANG Xue-wen. Analysis of granular flow formation and contact forces characteristics of load chain of scraper conveyor［J］.Journal of Mechanical & Electrical Engineering, 2021,38(8):968-974.