Increasing value added in an automotive assembly line. A case study

For an assembly line, one of the main concerns is how they distribute operations in order to achieve takt times. Nowadays the complexity of assembly operations don't allow the company to maintain a work balance which affects the inequity of the work stations' time and also generates non value added activities that is reflected in the total cycle time. The manufacturing plant of this study manually produces bus chassis, and has two assembly lines: urban chassis (UC) and foreign chassis (FC). Currently, the total of value added activities in the production process is 43%. The purpose of this research paper is to increase this value to 58% and balance the workload so each station operates within their assigned takt time (25 minutes UC and 250 minutes FC). In order to achieve this paper's main objective, the research team used a Lean Six Sigma approach and DMAIC methodology. The activities completed were the reduction or elimination of non value added activities to generate a balancing proposal and validate it through simulation. This paper is relevant for operations management professionals since it represents one of the most studied issues in manufacturing assembly lines, and provides an integrated approach combining different tools to solve this problem in a multinational company.