| Mitsubishi Power (Philippines) Inc. (MHI) is a manufacturing organization whose aim is to fulfill customer satisfaction and be globally competitive in boiler fabrication. The most common process in the manufacturing of boiler components is the welding process which contributes to the efficiency and productivity of MHI. In welding, the weld rejection rate is a loss in productivity since one should allot person-hours to repair welds. One reason organizations cannot maximize their profit is due to waste in productivity. In this study, the researchers proposed modifying the welding machine and optimizing its parameters to increase its efficiency and minimize the loss in productivity. The DMAIC model was used by the researchers to address the problem of MHI in weld rejection rate. The first level of Pareto analysis revealed that the orbital welding machine contributed 32.55% to the total rejection rate among other machines. In the second level of Pareto analysis for the orbital welding machine, porosity contributed the most percentage of 64.52%, among the factors that contributed to the rejection rate. These porosities are defects detected by radiographic testing located at the root passes. The problems that often arise in the Ishikawa diagram and Why-Why analysis are the wrong choices of welding parameters, underperforming orbital welding machines, and lack of mock-up welding. After modification and optimization, the rejection rate decreased compared to the prior modification and optimization. It means that the proposed solution by the researchers was practical and can minimize the loss in productivity. |
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