Research On Optimal Scheduling Of Printing And Dyeing Production Process

The manufacturing technique of the printing and dyeing is very complicated with many processes and diversified products.It is a typical flexible job shop production process.Domestic printing and dyeing workshop operation plan mainly depends on experienced staff,but it is difficult to achieve reasonable scheduling only by manual experience.The low degree of informatization and automation has become the bottleneck of enterprise development.The purpose of this paper is to improve the automated production capacity of printing and dyeing enterprises by studying the optimization scheduling problem of printing and dyeing production process and establishing a scheduling model suitable for printing and dyeing production process.Firstly,the static scheduling of printing and dyeing production process is studied and various factors that cannot be ignored in the actual printing and dyeing production process are fully considered.Then on the basis of static scheduling,a dynamic scheduling model of printing and dyeing production process is established to deal with two major disturbances:new order insertion and equipment failure.Among them,the main research contents are as follows:1.The printing and dyeing process is introduced and the printing and dyeing scheduling problem is described in detail.On this basis,a static scheduling model of printing and dyeing production process based on the pre-order method is proposed.In the model the factors such as process switching time,equipment preparation time,dyeing machine cleaning time and parallel machine are fully considered,so that it can better adapt to the actual production situation in the workshop.Through case simulation,the scheduling results and corresponding performance parameters are obtained and finally presented in the form of Gantt chart.The feasibility and validity of the static scheduling model for printing and dyeing production are verified by comparing the performance parameters with the simulation results of the existing static scheduling model for printing and dyeing.2.Considering the uncertainties in the production process of printing and dyeing workshop,simple static scheduling cannot achieve better scheduling effect.Therefore,on the basis of the static scheduling model a dynamic scheduling model of printing and dyeing production process based on rolling time horizon rescheduling method is proposed to solve the dynamic disturbance in printing and dyeing production process.Firstly,the dynamic disturbance of new order insertion is simulated and analyzed separately which includes inserting one order and inserting three orders.Then the dynamic disturbance of equipment failure is simulated separately and the scheduling result is obtained.Finally,a comprehensive case is given to simulate the production process of the actual printing and dyeing workshop.The comprehensive case includes three situations:inserting new orders,sudden failure of equipment,restoring equipment and inserting new orders at the same time.The feasibility and validity of the dynamic scheduling model of printing and dyeing production is verified by testing the model several times.