Improvement of transfer efficiency for furniture painting process

Coating applications are among the most crucial processes and significantly increases the durability and appearance of furniture. Ineffective application of the painting process in this industry increases paint consumption and coating defects, and has a negative impact on the environment. One of the significant reasons for these disadvantages is transfer efficiency. The aim of this study was to improve the transfer efficiency of medium-density fiberboard (MDF) painting process in a furniture manufacturing company using the DMAIC (Define, Measure, Analyse, Improve, Control) methodology. To achieve this goal, (1) the current painting process of transfer efficiency was evaluated using the Individual Moving Range (I-MR) chart and process capability index (C_pk); (2) the factors affecting the transfer efficiency were determined using the cause and effect diagram; (3) the factors affecting the process and the optimum factor levels were determined using Analysis of Variance (ANOVA) and desirability function; and (4) the transfer efficiency of the improved process was re-evaluated using the I-MR chart and process capability index. According to the results, the optimum parameter levels were determined as 24 cm for distance, 4.5 psi for air pressure, and 14% for dilution rate. The process capability index of C_pk improved from–0.37 to +1.66.