The effect of planned material flow on productivity in a production line: Application of POLCA method as an alternative approach

This study examines the impact of material flow on production line efficiency and evaluates the applicability of an alternative production control method, POLCA (Paired-cell Overlapping Loops of Cards with Authorization), particularly in manufacturing environments characterized by high product variety. In cases where traditional MRP systems fall short in managing variability, pull-based control systems come to the forefront with their potential to improve efficiency. Accordingly, the current state of a sample production line was analyzed, bottlenecks were identified, and an improvement model based on the POLCA system was proposed. Tools such as value stream mapping, Pareto analysis, and root cause analysis were used to identify inefficiencies in the process, followed by simulation modeling to measure the effects of the POLCA system. The results of the implementation indicate an 11% reduction in cycle time and a 34% decrease in waiting time. Additionally, a 2% increase was observed in the order fulfillment rate. In terms of cost analysis, a labor cost saving of 92,043 TL was achieved, and it was calculated that the same resources could enable 11% more production. This potential for additional output was estimated to correspond to a total profit increase of approximately 7.3 million TL. Efficiency analysis was conducted using output/input (product/labor hour) ratios, reductions in cycle time, time-based cost, and labor cost. Significant improvements were observed across all indicators. As a result, the POLCA system is considered an effective alternative for balancing production flow, reducing waiting times, and increasing productivity in manufacturing environments with variable demand structures.