Research on flow compensation technology for hydraulic system in working face

Currently, there is a lack of analysis on the pressure and flow characteristics of hydraulic systems during continuous propulsion in the optimization research of working face hydraulic systems. There is a lack of simple and effective solutions to the problem of pressure and flow fluctuations in hydraulic systems. In response to the demand for rapid support movement of the working face, with the construction of a new large mining height working face in the 2⁻² coal seam of Zhangjiamao Coal Mine as the engineering background, a single hydraulic support and a group hydraulic support simulation model are established using AMEsim software. Based on the action timing of the jack in the automatic follow-up and support movement, the hydraulic support movement and sliding process during coal mining are simulated. The study analyzes the pressure and flow changes of the hydraulic system in the working face when different numbers of hydraulic supports act simultaneously. It is pointed out that the reason for the slow movement of the supports is that the instantaneous liquid demand of the hydraulic supports exceeds the maximum flow rate of the pump station. At the same time, there is a contradiction between insufficient instantaneous liquid demand and excess liquid supply capacity of the pump station at some times during the movement of the hydraulic supports. Aiming at the intermittent high flow demand of hydraulic systems, a flow compensation technology based on accumulators is proposed. Through simulation verification, the pressure fluctuation of the hydraulic system is significantly suppressed after the installation of accumulators, and the movement speed of each jack is significantly improved. On site experiments are conducted on the flow compensation technology based on accumulator in the new construction working face of Zhangjiamao Coal Mine. The results show that after the accumulator is connected, the average pressure drop of the hydraulic system decreases by 74.1%, and the pressure fluctuation is significantly suppressed. This verifies that the flow compensation technology can meet the intermittent high flow demand of the hydraulic system and provide guarantees for rapid support movement.