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A cylinder-type pneumatic centralized precision metering device for rapeseed was designed. The structural composition, operating parameters and working principle of metering device were analyzed. The single factor and orthogonal experiments were conducted. The rotational speed of seeding cylinder, positive pressure and negative pressure were used as the experiment factor. The bench experiments showed that the damage rate was below 0.5%. When the rotational speed of seeding cylinder was 20 r/min,the positive pressure and negative pressure was 2200 Pa and -2200 Pa, it was found that the quality index was 94.02%, the loss index was below 4.0%，and the variation coefficient of the consistency of each line displacement and stability of the total displacement were 5.73% and 1.21%, respectively. 