Theory and Practice of Controllable Agile Pressure-Stabilizing Liquid Supply System of Coal Face

To address the challenge of stabilizing fluid pressure during the advancing process of a fully mechanized mining face, a controllable agile pressure-stabilizing liquid supply system based on an accumulator station was proposed and tested at the Hongliulin 25216 working face. Based on the parameters of the hydraulic supports, a full-face simulation model was established. The pressure fluctuations and fluid demand during the hydraulic supports advancing were analyzed. The results indicated that when paired supports advanced, the advancing time meet the working face requirements; however, severe pressure fluctuations occurred at the support inlet, and the pump station experienced additional overflow losses. To solve excessive pressure fluctuations and energy waste in the pump station during hydraulic supports advancing, a scheme was proposed to deploy a controllable agile pressure-stabilizing liquid supply system with a large-capacity accumulator station at the equipment train. This system achieves the effects of rapid fluid replenishment under low pressure and quick pressure increase when the column lifting by controlling the connection between the accumulator station outlet and the main inlet pipe. Simulation analysis showed that after adding the system, the advancing time was reduced by 26.0% and pressure fluctuations were decreased by 45.3% compared to the non-deployed situation, effectively improving the liquid supply quality in the working face. Compared to only using an accumulator station, the advancing time was further reduced by 5.3%. An accumulator station consisting of three groups totaling 18 bladder accumulators was designed, along with the control system and valve bank. Underground application results demonstrated that after activating the controllable agile pressure-stabilizing liquid supply system, the pressure fluctuations at the outlet of the pump station were reduced by 66.0%, the pressure disturbances were significantly suppressed, and the pressure stabilization effect was evident. This research provides an effective solution for high-quality stabilized liquid supply in mining faces.