| Rail sleeper bolts are important components installed on both sides of the rail to fix the rail.The complex and variable outdoor environment may cause the bolts to rust and fail,affecting the safety of train operation.Therefore,regular application of rust-proof oil is required.Currently,most domestic rust-proof oil application methods still rely on manual application,which is performed in harsh working conditions and with low efficiency.Some have started to use spray equipment,but they are limited by equipment performance and can only spray rust-proof oil with low viscosity,resulting in less-than-ideal anti-rust effects.Compared with traditional spraying,high-pressure airless spraying technology has the advantages of better spraying atomization effect and ability to spray high-viscosity fluid.In this paper,airless spraying technology is used for rustproof oil spraying,and its spraying parameters are simulated and tested.An automatic rust-proof oil coating device is developed and designed,and the main research contents are as follows.Analysis of the requirements for the rust-proof oil coating operation of rail sleeper bolts is conducted,and the principle and technical scheme for rust-proof oil spraying of rail sleeper bolts are determined.Based on the fluid spraying atomization principle,the atomization and fragmentation mechanism of high-pressure jet in the air is analyzed,and the difficulties in the spraying process of high-viscosity fluids are discussed.By conducting rheological property experiments,the empirical viscosity model of high-viscosity oil is established.Based on the nozzle channel structure and fluid parameters,the theoretical calculation model of the nozzle flow rate is established,providing a basis for subsequent theoretical and simulation research.A simulation calculation model of the nozzle flow field of the spraying system is established using Fluent software.The influence of spraying pressure,fluid viscosity,and nozzle structure parameters on the jet atomization angle,j et velocity,and nozzle flow rate is analyzed.The results show that the spraying pressure mainly affects the jet velocity and atomization particle size,and the fluid viscosity has an important influence on the flow rate,diffusion angle,and atomization fragmentation mode.The nozzle structure parameters mainly affect the flow rate and diffusion angle.Based on the simulation results,a prediction model for nozzle jet diffusion angle and flow rate is established.According to the working principle of the spraying system,an experimental platform for spraying atomization effect is constructed.The influence of various spraying parameters and nozzle structure parameters on spraying atomization effect is experimentally studied,and conclusions similar to the simulation results are obtained,proving the accuracy of the simulation model and results.Based on the measured spraying angle and nozzle flow rate data,the predicted model obtained from the simulation is corrected to eliminate the prediction error caused by pipeline resistance and obtain a more accurate prediction model.According to the prediction model,optimal spraying parameters under different working conditions are given.Based on the analysis of the technical requirements and operation process of rail sleeper bolt anti-rust oil coating technology,combined with the high-pressure spraying scheme proposed in this paper,the working principle and functional modules of the oiling equipment are analyzed,and the detailed structure design of the oil supply module,spraying module,walking module,etc.are completed.The strength of the equipment is analyzed by using the finite element method.The touch screen PLC is used for walking,bolt induction,and automatic control of spraying,and the development design of the electrical control system software and hardware of the equipment is completed.This provides an efficient and automated technical equipment for the maintenance of rail sleeper bolt anti-rust spraying operations. |
PDF Full Text Request