Study On The Remaining Life Evaluation Of The Bogie Frame And Maintenance Plan Of Monorail Vehicle On Chongqing Rail Transit Line 2

The bogie is the most critical core component of a straddle monorail vehicle,and the frame is the main foundation of the bogie.The frame is the most important structure for the running part of the bogie,and it is the installation foundation for basic system equipment such as vehicle suspension system,traction drive system,basic braking system,wheel set axle box system and spring damping system.The structural performance of the frame has a direct impact on the safety,quality and life of monorail vehicles.In order to confirm whether the first batch of straddle monorails on Chongqing Rail Line 2 can continue to operate safely after reaching the design life of 15 years,this paper uses the method of calculation and analysis,combined with actual vehicle material sampling experiment and line test to analyze the remaining life of bogie of the straddle monorail vehicle on Chongqing Line 2.This paper takes the bogie sampling of 84 straddle monorail vehicles of Chongqing Rail Line 2 with a design life of nearly 15 years as the research object.First,the structural strength analysis of the bogie frame is carried out,and the limit of the bogie frame is established.The meta-model analyzes the static strength and fatigue strength of the frame,and determines the focus of the test according to the distribution and status of the static strength and fatigue strength characteristic points;secondly,the physical and chemical properties of the existing frame materials are tested,tensile and impact tests,and welding Seam metallographic analysis,through physical laboratory testing,the physical and chemical properties and mechanical defects of the in-service bogie materials were evaluated;then the bogie frame was tested on the front line according to the prepared bogie front line test plan.Measured the load data at the key positions of the bogie frame,conducted a statistical analysis of the dynamic stress amplitude of the power bogie,and compiled the stress spectrum;finally,based on the measured data of the bogie frame stress line,the P-C-S-N theory analysis and the equivalent stress were used respectively.Four different methods,including railway vehicle specifications,IIW standards and BS7910 standards,were used to calculate the remaining life of the bogie frame,and the fatigue limit of the bogie was checked using the equivalent stress Japanese JIS bogie specification.The analysis,test and research results show that the fatigue life of the bogie frame of the 84 straddle monorail vehicle project on the newer line of Chongqing Rail Line 2 under the above four methods is 15.88 years,16.42 years,22.44 years and 16.52 years,respectively All are longer than the design life of 15 years,with a certain safety margin.On the basis of the above research,this article combines the results of vehicle material inspection,structural state inspection,life calculation,system continuity use analysis and comprehensive economic analysis,and proposes the suggesting maintenance of this batch of vehicles with certain application value before returning..The research results of this paper provide an important basis for the maintenance decision of the bogie frame of the 84 straddle monorail vehicle project on Chongqing Metro Line 2,which saves the cost of straddle monorail maintenance and is also relevant for future development,research,formulation of vehicle maintenance system and optimization design of bogie structure provide reference.