The Minimizing Batch Size And The Best Number Of Batch Research Of Multistage Work Shop

Since the new century, the world economy developed rapidly, the economy of our country also developed by leaps and bounds. Manufacturing.as a pillar industries of a nation, its development doesn't allow of ignorance. The development of science and technology is the core of manufacturing development strength. But in relying on technology to enhance economic strength, a phenomenon is also born quietly, that is overproduction. Overproduction will lead to overstocking products, and if the product needs to experience lots of process, it will also produce lots of work in-process. The overstocking of these products will not only occupy the limited inventory space of enterprise, but also create more obstacles to production management, slow down the operating of fund and so on. The damage should not be underestimated.Since last century, there are many scholars researching on work in-process systematically and deeply. Particularly since President Hu Jin tao proposed building a resource-conserving society. How to reduce the WIP and implement the lean production attracts much attention and research of much more scholars.This paper mainly studies the work in-process inventory under the environment of multistage production.in order to make the in-process inventory level minimum in premise of satisfy the needs of customers and make production smoothly. This paper makes a simple introduction and description for some basic theory of work in-process firstly, analysis some key factors which influence the quantity of work in-process inventory under the environment of multistage production. Such as,the batch and batch of work in-process transportation, each stage of the production cycle time, takt time and so on. Based on this, this paper studies the relationship between work in-process inventory of each stage and these factors again on the basis of previous studies, establish a new mathematical model about work in-process inventory. This model evaluates the production value of enterprise in each unit time. This model not only introduced cycle time and takt time, but also considered the influence from overproduction, considered thoroughly, and truthfulness.This paper conduct a deep theoretical argument for the model by using Lagrange multiplier, proves the rationality and accuracy of the model. This paper also put the model into practical application, and the effect of application is all right. This model is a nonlinear integer programming model in the constraint condition of multivariate nonlinear, belongs to the problem of NPHard(nonlinear programmable problem). The solution is very complicated. This paper adopts branch definition method to search integer, got the optimal feasible solution of this model, namely, got the best batches and batch of the transportation of work in-process in each stage, then make the total work in-process inventory level minimum. At the same time, it conducts the visual illustrations for the calculated result by using the Lingo and Matlab. This paper conduct a systematic research of the work in-process in each stage of multistage production, and building a new mathematical model about the work in-process inventory, see the batch and size of the transportation of the work in-process as variables. Then conduct the theoretical demonstration and practical application of this model. In the premise of make the production smoothly, it make the work in-process inventory of enterprise minimum and make the production value maximum.Small batch production is the core element of lean production, so the research of this paper plays a guiding role of security the enterprise to implement the lean production.