Structural analysis and fatigue prediction of harrow tines used in Canadian prairies

Abstract

Canadian prairies are renowned for their agricultural contribution to the global food market, where harrow tine is a critical component of agricultural equipment used for soil preparation and weed control before crop cultivation. Unfortunately, during operation, these tines are exposed to repetitive cyclic loading, which eventually causes fatigue failure. Commercially available three different harrow tines named 5-1895, 5-2709, 5-2776 undergo an experimental fatigue evaluation and are validated through a numerical approach using Finite Element Analysis (FEA). After that, fatigue life estimation for different deflections under different circumstances in the real field was determined where 5-2676 showed ground-breaking life compared with others. The results of the study showed that the fatigue life is highly dependent on geometry, number of coils, pitch angle, leg length, and coil diameter. 0.354 HT model resembles 5-2776 developed to investigate the effect of wire diameter. For this reason, the experimental SN curve for ASTM A229, Class I was developed utilizing the fatigue bending test. Following this, a comparative study between six harrow tine models was analyzed based on their harrowing ability against identical deflections. This study also identified critical locations of stress concentration, which could be used to optimize the design of the tines to improve their fatigue life. Experimental fractured surfaces went through morphological investigation. This research has an impeccable impact on prairies’ agricultural acceleration by saving time and unpredictable fatigue failure often faced by farmers through designing more reliable and durable harrow tines, which can reduce agricultural maintenance costs and increase efficiency. Keywords: Fatgue failure, Harrow Tine, life estimation, S-N curve, ASTM A229.