Reliability optimization design of connecting rod of locomotive traction equipment

High reliability of a locomotive is important for the railway transportation. This high reliability was guaranteed by use of a large safety factor resulting in cost increase of railway transportation generally. To overcome this high cost without sacrificing reliability, this work focuses on an optimization design method for the design of the connecting rod used in locomotive traction equipment. The reliability model is formulated based on the stress–intensity distribution interference theory and the reliability of the original connecting rod was estimated using advanced first order and second moment method. Then, the reliability–sensitivity is analyzed. The results show that the reliability of the connecting rod used in China is almost equal to one and the reliability robustness is high. To minimize the quality of the connecting rod under the condition of ensuring high reliability and reliability robustness, the reliability optimization models are proposed for three cross sections. The optimization results show that the quality of the optimized connecting rod could be reduced to less than 40% of the original without sacrificing reliability and reliability robustness.