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In order to solve the problem of perforation and screen tube blocking and fixed valve leakage caused by the adhesion of coalbed gas well pulverized coal in the perforation, screen tube, pipe wall, pump barrel and pump valve. Based on the theory of static adhesion, a startup model of variable passage dynamic adhesion of pulverized coal was established, and the dynamic adhesion mechanism of pulverized coal on the pipe wall of coalbed gas well was analyzed. Through the combination of theoretical modeling and indoor experiment, the influence of well fluid temperature, pulverized coal mass concentration, pulverized coal particle size, well fluid velocity, etc. on the dynamic adhesion law of pulverized coal pipe wall was comprehensively considered. Based on the control variable method, the experiments of various factors affecting the dynamic adhesion of pulverized coal pipe wall are carried out. The dynamic adhesion characteristics of pulverized coal on the tube wall under different well fluid temperature, well fluid velocity, pulverized coal mass concentration and pulverized coal particle size were obtained, and the dynamic adhesion rules of pulverized coal on the tube wall under different conditions were given. The results show that the pulverized coal adhesion rate increases with the increase of pulverized coal particle size, pulverized coal concentration and well fluid temperature, and decreases with the increase of well fluid flow rate. It is concluded that the adhesion characteristics of pipe wall pulverized coal provide theoretical basis for the design of coalbed gas well pipe wall pulverized coal flushing process, and have important significance to ensure the continuous and stable production of coalbed gas well. [ABSTRACT FROM AUTHOR]