Taking the successful practice of the secondsealingplugging as background under pneumatic conveying for the studyestablished an idealparticletransport model in coal fracture and obtained that the types of coal fracture seriously affect the state of particle migration.In the curved crack,the particles move in waveform curve,while in the linear fracture,the particles move with decreased acceleration until uniform linear motion.Simultaneously,solved the expressions of the particle velocity and acceleration in the linear fracture,and made indepth qualitative and quantitative analysis about the solved expressions.In the Huachu Coal Branch of Liuzhi Industrial and Mining Corporation,conducted a field testthe results show that when the drilling of gas drainage goes into the decay time,the implementation of the second sealing can significantly improve the concentration of gas extractionand appropriately increasing sealing pressure can significantly improve blocking efficiency and effect in the second sealing section.Obviously,the test results is consistent with the model theoretical analysis.