Study On Precise Weighing Device Of Reactive Dyestuff Powder

With the demand for high-quality development of the printing and dyeing industry,the demand for high-end equipment in the printing and dyeing industry is increasing.For the cheese dyeing industry,the automatic weighing of dyestuff with high accuracy and efficiency is an important part of the cheese dyeing process,which is of great significance for improving dyeing quality,dyeing efficiency,and reducing labor costs.Aiming at the problems of low weighing efficiency and accuracy of the dyestuff automatic weighing process in the cheese dyeing process,based on the traditional spiral feeding device,the feeding mechanism was optimized and a multi-stage automatic weighing method was proposed.The experimental prototypes with different ranges were developed and experimental investigations were carried out.The Experiments proved that the experimental prototypes have the features of stable feeding,high weighing accuracy,and high weighing speed,which can meet the automatic demand of printing and dyeing enterprises.Taking reactive dyestuff that commonly used in the cheese dyeing process as the research object,based on the study of the powder flowability parameters of the dyes,a hopper was designed according to the Jenike theory.In order to avoid powder arching in the silo,the arch breaking mechanism was designed to meet the overall evenly unloading.A new type of spiral feeding mechanism was designed,and the feeding effect of the feeding mechanism was simulated with the discrete element method;The design of the powder return mechanism combined with PID adjustment can improve the stability of the outlet flow rate,which can solve the problems of blockage and over-tolerance of the existing mechanism,and realize evenly feeding and precise control in the powder weighing process.A multi-stage automatic weighing control method that can balance the speed and the accuracy was proposed.An automatic control system based on PLC was built.The weighing process was divided into multiple stages,and the baffle was driven by the stepper motor to adjust the area of the discharge port.The control parameter of the gear planning and the mass weighing ratio of each gear was optimized to achieve high-efficiency feeding under the premise of high weighing accuracy,and to achieve a balance between weighing accuracy and weighing speed.Two experimental prototypes with different weighing ranges(500g and 32kg)were researched and experimental study was carried out.With collecting process data of the whole weighing process,study on the influence of discharge area and shaft speed on feed flow was carried out,which can provide the data basis for the parameter optimization.Through the data analysis of the full-range automatic weighing process,the mass boundary was calculated.The weighing process with different shaft speed was repeated three times,and the calculation result of mass boundary was stable.Using the mass boundary calculation method,the automatic weighing experiments with high accuracy were carried out.The average relative errors of the multiple weighing results were 0.0068% and 0.013%,respectively.During the experiments,there was no over-tolerance.The experimental results show that the weighing method and the prototype researched in this paper have the characteristics of high weighing accuracy,high weighing efficiency,and good stability,which can meet the production requirements for enterprises.