Production sequencing in a flow shop system using optimization and heuristic algorithms

Abstract

The purpose of the research was to determine the sequencing of the production of n jobs in m operations in a small footwear company in an environment of flow shop machine characteristics, which optimizes the total time of completion of the job in the production system (Makespan). We used heuristic algorithms that were applied through Lekin and WinQSB softwares, and for the optimization algorithm we designed a mathematical model that was solved by Juliabox software. Results show that the integer linear programming and local search minimize the makespan with 3807 minutes, and different production sequences for each algorithm, which consider permutation, which improves the traditional way of programming the production in 97 minutes, however, the optimization presents better results in the performance measures of average waiting time, average time of flow, and average job in process. Application of heuristic algorithms proves to be simple and fast, but the mathematical model of optimization designed and encoded in the software is a flexible and valuable tool for decision making in production programming, which could be applied in other footwear companies, and in other productive sectors whose companies have the same characteristics of the case study, reducing costs and improving delivery times.

Optimization model to increase the efficiency of the flexible packaging production process applying the Johnson Method, SMED and TPM in a SME in the Plastics Sector

“…Currently, manufacturing companies choose to increase their production efficiency through the selection and application of programming techniques that serve as a support to achieve the optimization of manufacturing times [11] [12]. One of the most used techniques in the industrial sector is Johnson's Rule, because it provides consistent improvements in the production flow, machine utilization, downtime, and average lead time [13] [14]. Several studies show the application of Johnson's Rule to solve the difficulties in sequencing operations with independent configuration times.…”