The development of restoration technology and meadows, improvement of run-down pastures, and productivity improvement of old crops of perennial grasses is an urgent problem in agriculture. The tillage traction force in seeder designing and manufacturing is an important indicator of energy efficiency. The objective of this work is to reduce traction force and ensure seeding depth uniformity by justifying the optimal chisel parameters of a grain–fertilizer–grass seeder for direct seeding in sod. The Box–Behnken method was applied to investigate the traction force dependence on the seeder velocity, seed embedding depth, chisel width, and mounting angle. The obtained optimal parameters of coulters were justified by the finite element method. Structural and technological parameters were checked using the smoothed-particle hydrodynamics method on the deformation and wear of the seeder working body. The revealed optimal coulter parameters were as follows: chisel width was 20–20.97 mm, chisel length was 145–148.9 mm, mounting angle was 75°–81.6°, and achieved minimum traction force was 720 N. These parameters ensure the quality of grass seed embedding in the sod. The theoretical data of traction force (8.27–8.39 kN) are in accordance with the experimental (8.28–8.63 kN) data under field conditions. These findings are efficient in agrotechnical and mechanical predictions regarding the occurrence of chisel residual stresses and the working lifetime of the part.

This article presents the results of an experimental study on improving the durability of cup cutters through pre-processing. A review of existing methods of increasing the durability of metal-cutting tools is carried out. The conducted experiments and simulations confirmed the application of pre-processing to increase the durability of cup cutters and the hardening of the cutting part after pre-processing, which approves the formation of a secondary contact structure in the pre-processing process. Dependence for determining a period of the durability of cup cutters at various regimes of pre-processing is deduced.

The aim of the research was to reduce the irregularity of mineral fertilizer granule flow by developing a tedder-vaulting breaker that prevents the formation of vaults over the sowing windows of the seeder hopper. Existing dosing devices for mineral fertilizers do not provide stable application of the required doses of mineral fertilizers due to vaulting as well as accumulation and sticking of fertilizers in hoppers. In order to achieve a stable and precise metering of high fertilizer doses, a crank tedder is suggested to be mounted inside the hopper. Its function is to break the constantly appearing dynamic vaults above the sowing windows and to crush the fertilizer clods, i.e., to provide the fertilizer sowing units with a continuous flow of material. Theoretical studies were carried out using methods of classical and applied mechanics, special sections of higher mathematics. The following optimal parameters were established: the tedder blade width 0.05–0.09 m, the radius of the elbow 0.028–0.034 m, the blade installation angle 23–27°, and the kinematic mode of the tedder k = 1.5–1.9. Experimental studies have shown that the use of a crank tedder provides a stable flow of mineral fertilizer granules through sowing windows and reduces the sowing unevenness between seeding units by 12–15% and sowing instability by 7–10%. At the same time, the degree of damage to granules of 1–5 mm size is insignificant and is within 2.8–3.5%.