THE INFLUENCE OF SEED VARIETY AND HIGH SEEDING SPEED ON PNEUMATIC PRECISION SEED METERING

ABSTRACT

Pneumatic seed metering devices are widely used in high-speed and precise corn seeding operations. The objective of this study was to analysis the high-speed seeding performance of a pneumatic precision seed metering device at seeding speed ≥12 km/h. In this study, full-factor experiments were conducted of an air-suction rotary-hub corn precision seed metering device at the early stage of development. Seed leaking was the primary failure mode, and the experimental factors had no evident regular influence on the repeat index. The negative pressure of 3-7 kPa had significantly positive and negative correlations with the qualified index and the leak index, whereas the seeding speed of 12-20 km/h was significantly negatively and positively correlated with the qualified index and the leak index, respectively. The leak index reached its greatest value of 32.48%, 15.61% and 66.77% when the negative pressure was 3 kPa, and it was always less than 10% when the negative pressure was greater than 6 kPa for the three corn seed varieties. The corn seed varieties with smaller sizes and regular shapes were more suitable for high-speed precision seeding operations above 12 km/h, and the negative pressure could be increased to improve the qualified index and reduce the leak index.

corn; seed meter device; high-speed seeding; precision seeding; experiment