Simulation And Optimization Research On Production Planning And Scheduling Of Pipe Processing Workshop In Shipbuilding Enterprises

Pipe production in shipyard is an important process in ship manufacturing. A ship production needs thousands of pipes to match the process, thus the plan of pipe production have a great influence on the ship production cycle. Aiming at the problem of long processing cycle and large volume of work in process, caused by the facts that planners can not caculate the process time of each pipe and scheduler can not measure the process capacity & required capacity in different procedure accurately. A research method of simulation and optimization of production plan & control was proposed. The method tried to solve the problem of production plan and flexible resource schedule systematically and quantitatively.The article first analyzed the situation of process and production planning & scheduling of pipe workshop, and then proposed the demand of production planning simulation; Through the study of the theory of production planning & scheduling and system modeling and simulation; At last, combined with the actual situation of tube plant, the paper proposed the process of simulation and optimization of production planning & scheduling from a collection of work: data collection, databases, simulation modeling and optimization scheduling.In the data collection study, considering the features of variable type, large quantities, small batch and single manufacture in the pipe production and the fact of the low level of information technology in pipe workshop. The article proposed a method which combined the work sampling with stopwatch time measurement to collect the deterministic data and uncertainty data effectively in the workshop.In the simulation database study, focusing on the structure feature of pipe, process facts of bill of materials and map of production. The article established the product information structure which could be identified by simulation software; defined the relationship between simulation model and simulation database; designed the process flow by which simulation model could read the information from simulation database; proposed the method by which the process time of each pipe in different procedure could be caculated. Through importing information about material list by computer program and production map information manually, the task of database information inputting was completed.In the simulation modeling study, considering the process flow of pipe production and the flow by which simulation model read information from database, the paper established the simulation logic of pipe workshop using the software of Arena. Through the simulation logic model combined with the deterministic data and uncertainty data collected, the paper established the simulation model.In the optimization scheduling study, considering the instability of resources's load proportion aroused from the change of plan in pipe workshop. A problem of flexible resource allocation with the target of minimum processing cycle was proposed. Through establishing the ability efficiency matrix, resource allocation variable matrix and the formula of production capacity of each process, proposed a solution method based on Arena12.0. At last, the optimization scheduling of flexible resource was studied according to different production plan.The method and results from the study of production planning & scheduling simulation could provide a sounding validity support for planner & scheduler in pipe workshop. Meanwhile, the method could provide reference for other similar workshop.