Case Study Applying Six Sigma to Reduce Defects of DC Recessed LED Downlight
Online First: 03/07/2026
Corressponding author's email:
hieunk@hcmute.edu.vnDOI:
https://doi.org/10.54644/jte.2026.2105Keywords:
DMAIC, LED downlight, FMEA, Six Sigma, Defect rateAbstract
This study applies the DMAIC process to improve the defect rate of DC recessed LED downlights at Company X. The author used quality management tools, including the fishbone diagram, the 5 Whys method, and FMEA analysis, to identify the root causes of major defects. The analysis is based on assessments of the R&D team leader, production team leader, and QA and QC staffs. Analysis results showed that no-light or flickering defects accounted for the highest proportion, 61.67% of the total defects. After analyzing root causes and implementing improvement solutions, such as standardizing welding techniques, adding voltage-testing stations, performing tensile testing, and improving wire-holding jigs, the no-light or flickering defect rate decreased from 9.87% to 3.00%. The Sigma level of the process increased from 3.6 to 4.0, resulting in a more stable and efficient operation. The study confirms the effectiveness of applying the DMAIC method in enhancing production capacity and competitiveness for businesses in the lighting equipment sector.
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