Design and Experiment of Integrated Machine for No-till Precision Seeding and Straw Mulching for Corn and Soybean Strip Compound Planting

Abstract

For corn and soybean strip compound planting mechanized sowing process in the field of large amount of straw, substitute equipment sowing quality was poor, low operating efficiency and other issues, the design of a post-harvest stubble land conditions at a time into the ground can be synchronized to complete the “clearing of straw anticlogging seed bed finishing-corn and soybean sowing fertilizer-straw uniform cover” integrated machine. In accordance with the agronomic requirements of corn and soybean strip compound planting, the structure of the integrated machine was designed, and its working principle and corresponding technical parameters were given; according to the agronomic characteristics of corn and soybean strip compound planting, the lateral spacing of the straw clearing assembly in the straw clearing and mulching device was determined through theoretical calculations; by combining orthogonal experiment and discrete element simulation, simulation analysis and parameter combination optimization were carried out on the structure of straw clearing and mulching device, when the operating speed was 9.9km/h, the rotational speed of cutter shaft was 625r/min, the number of helix heads of the straw clearing assembly was 3, and the inclination angle of stubble spreading control plate was 90°, the straw clearing rate was 91.03%, the mulching uniformity was 87.05%, and the equivalent power consumption was 9.79kW; adopting the single-factor experiment method, the whole machine field performance experiment was implemented in the corn stubble land with 1.48kg/m2 residue of crushed straw after machine harvesting, and the results showed that when the operation speed was 7.2km/h (to ensure the normal work of the seed dispenser of the experimental prototype), the grain spacing of soybean was 8cm, the grain spacing of corn was 10cm, the depth of the knife teeth in the soil was 50mm, the machine passed well, the qualified index of grain spacing of soybean and corn were 79.50% and 88.66%, the index of reseeding were 4.03% and 3.66%, the index of leakage of seeding were 16.48% and 7.68%, and the coefficient of variation were 28.49% and 21.31%, respectively, and the qualified rate of sowing depth of soybean and corn were 90%, the qualified rate of fertilizer depth were 80%, and the qualified rate of horizontal spacing of seed and fertilizer were 80%, the uniformity of straw covering was 88.97%, and there was no seed drying phenomenon in the field after sowing. The research results laid the foundation for the development of the integrated machine for precision sowing of corn and soybean strip compound planting and the popularization and application of technology of corn and soybean strip compound planting.

Keywords:corn and soybean strip compound planting;integrated corn-soybean precision planter;clearing and mulching straw;orthogonal experiment;discrete element