Portable Air Compressors,Electric Air Compressor,Air Compressor small,Industrial air compressor AWLOP CO.,LTD , https://www.awlop.com
Study on Fluid Management of Reasonable Bolts for Tilting Plows
Safety bolt calculation is a critical aspect when determining the stress conditions of the safety bolt. It is essential to carefully select each coefficient in the formula used to calculate the plow's traction force. These coefficients should be based on the specific conditions of most farmlands in the region, as well as the plowing depth and width. The values must be neither too high nor too low, as this can lead to either unsafe operation or excessive breakage of the safety bolts, reducing work efficiency.
If the coefficients are chosen too large, the safety bolts may not break when necessary, which could result in damage to other critical parts of the plow, such as the plow body or frame. On the other hand, if the coefficients are too small, the safety bolts may break too frequently, leading to unnecessary downtime and maintenance costs. Therefore, based on the typical field conditions in most areas of Xinjiang, the following parameters were selected: plowing depth (a) = 33 cm; plowing width (b) = 800 mm; tractor speed (vâ‚€) = 2 m/s; plow weight (G) = 6370 N; horizontal element line angle (θ) = 52°; radius of the plow body guide curve (R) = 352 mm; soil ejection angle (β) = 61°; friction coefficient (f) = 0.4; soil compressibility (kâ‚) = 1450; soil adhesion coefficient (kâ‚‚) = 0.030; soil-metal friction angle coefficient (k₃) = 1.45; and soil density (Ï) = 1.15 × 10³ kg/m³.
Substituting these values into the traction resistance formula, we calculated the total resistance (P) as follows:
P = fG + [kâ‚(1/R + kâ‚‚)² + k₃]ab + ½Ïabv₀² / 10 sinθ cosβ = 11786 N.
The force acting on the safety bolt (N₃) was then determined using the formula:
N₃ = P * ab * sinα / bcsinθ = 11786 × 448 × 202 × sin7° / (142 × 95 × sin52°) = 12227 N.
For finite element analysis, a solid model of the safety bolt was created using SolidWorks, and the COSMOSWorks module was used for meshing. The model was divided into 9290 nodes and 46,593 three-dimensional tetrahedral elements. The material used was AlloySteel, with mechanical properties including an elastic modulus (E) of 2.1 × 10¹¹ Pa, Poisson’s ratio (μ) of 0.28, and yield strength (σₛ) of 6.2042 × 10⸠Pa. Since AlloySteel is a ductile material, the yield limit was taken as the ultimate stress for the calculation.
During the analysis, it was observed that the maximum stress occurred at the connection between the screw and the nut due to stress concentration. The calculated von Mises stress was 3.708 × 10⸠N/m², while the material's ultimate strength was 7.238 × 10⸠N/m². This satisfies the condition σ_vonmises / σ_limit < 1, and the safety factor of the design was found to be 1.662. Considering potential impact loads and occasional deep plowing during operation, this safety factor was deemed sufficient.
Field tests were conducted on the 1LB-240 horizontal pendulum plow at the Fourth Team of Changji Military Farm in Xinjiang. The results showed that:
1) In heavy clay soil with a plowing depth of 400 mm, the safety bolts effectively protected other components of the plow from damage.
2) The safety bolts performed reliably under normal working conditions.
Overall, the designed safety mechanism proved effective in ensuring both operational safety and durability.