Research On SMED And Production Scheduling Optimization In Die-casting Workshop Of H Company

With the continuous improvement of the development level of manufacturing industry,customer demand is gradually diversified,and enterprises are gradually changing to the flexible production mode under the fierce market competition.The characteristics of mass production of multiple varieties in die casting workshop require continuous mold replacement.The length of die changing operation determines the production flexibility of workshop,and also affects the size of production batch and inventory.Die changing operation time has a great impact on the production efficiency and production cost of enterprises,and is an important factor for the development of production scheduling scheme.Therefore,it is of great theoretical and practical value to study the rapid die changing and production scheduling of the production system in die casting workshop.This thesis takes the die casting workshop of H Company as the research object,analyzes and improves the die changing operation,abstracts the production scheduling problem as the single process parallel machine batch scheduling problem for research,and uses the improved particle swarm optimization algorithm to solve it.Finally,the scheduling scheme generated before and after the optimization of the die changing operation is compared and explained in detail as follows:Firstly,the production status and characteristics of the die casting workshop are described,and the die changing operation is analyzed.The die changing operation is optimized by using industrial engineering theory and rapid die changing method.After the improvement,the die changing time can be reduced by 50%.Secondly,taking the production workshop of die casting as the background,it was abstracted as a batch scheduling problem of parallel machines in a single process,and the production order was divided into sub-orders with different delivery times,and the sub-orders were used as sub-batches for scheduling.In order to minimize the comprehensive production cost,which consists of mold change cost,storage cost and delay cost,the corresponding mathematical model is established.Then,the particle swarm optimization algorithm was designed to solve the problem,and the neighborhood search algorithm was used to improve the particle swarm optimization algorithm due to its characteristics of prematurity and poor robustness,and the solution results were compared with the scheduling scheme generated by human experience to verify the effectiveness of the algorithm.Finally,a large-scale case of actual production in die casting workshop was used to solve the problem,and the results were compared with the scheduling scheme after optimizing the die changing time.The results showed that shortening the die changing time could effectively improve the production efficiency of equipment and reduce the comprehensive production cost of workshop.There are 29 pictures,26 tables and 90 references in this thesis.