Research On Inventory Control Of Manufacturing Enterprises Based On TOC

“The theory of constraints”(TOC)founded by Dr.Glodratt is an advanced management theory which enterprises to achieve business goals based on the elimination of bottleneck.In the context of the country's implementation of the "China made 2025" action plan to revive the real economy,how to apply TOC to the inventory control of the traditional manufacturing enterprises to eliminate the bottleneck of the production system and improve the overall efficiency and competitiveness of enterprises is a problem worthy of study.The economic batch method(EOQ),inventory classification management method(ABC),manufacturing resource planning(MRP ?)and JIT production(JIT)represented the traditional inventory control methods that have been widely used in enterprises.Each of these methods has their unique advantage,while they also have a common defect,which is the excessive pursuit of local optimization and believe that local optimization can bring the optimization of entire production system.TOC thinks that the bottleneck of production system really determines the output capacity of the whole production system,only accurately find bottleneck of the production system,efficiency release the output of the bottleneck and balance the upstream and downstream WIP logistics of the bottleneck,can maximize the throughput of the whole production system and continuously optimize the enterprises.The "drum-buffer-rope" inventory control method(DBR)is a specific application of the theory of constraints to Schedule Inventory in manufacturing systems,this paper showed the advantages of this method compared with the traditional inventory control methods through the comparative analysis,but also found that there are three problems of DBR in specific application and theoretical studies :(1)the current identification methods of the bottleneck resource is not accurate enough and complexity for calculation,which is not convenient for the enterprises to application the DBR in the actual production process;(2)the specific calculation method of bottleneck resource more dependent on experience judgment,lack of objective and accurate;(3)in the respect of balance the bottleneck upstream and downstream logistics,the calculation process of the batch processing and transport volume of DBR is complicated,which is not as simple and efficient as the elastic pull replenishment mode of JIT.According to the above three problems,this paper puts forward three measures:(1)proposed to identify bottlenecks of the production system by using WITNESS simulation software;(2)design a calculation model of time buffer capacity based on system availability;(3)pull replenishment mode of JIT was introduced into the DBR.The fourth chapter of the paper makes a specific research of above three improvements,the fifth chapter of the paper take a bumper manufacturing enterprise as an example,carry out a case analysis by modeling and Simulation of production system of the enterprises through the witness software,in the case the result of DBR in the fourth chapter is used.The case analysis results show that the improvement research results of DBR can further enhance the equipment utilization of bottleneck and improve the overall output of enterprise production system,contribute to the application of DBR in manufacturing enterprise.