IMPROVING THE EFFICIENCY OF THE MOTOR PRODUCTION PROCESS TO REDUCE WASTE THROUGH THE APPLICATION OF LEAN CONCEPTS: A CASE STUDY OF A MOTOR MANUFACTURING PLANT

Abstract

This study investigates production issues in the motor assembly department of a company producing motors for washing machines and air conditioners, which experienced rising production costs in 2023. The waste volume increased notably in December 2023, resulting in a total loss of 1,631,908.11 Baht. The analysis with bar and Pareto charts revealed that LINE B incurred the highest loss at 303,305.02 Baht, primarily due to noisy motors (A22), with a loss of 88,414.40 Baht. A fishbone diagram analysis, Pareto, Numerical results and OEE showed the root causes were machinery and mold issues due to insufficient maintenance and mold wear. To address these issues, Lean principles and Total Productive Maintenance (TPM) involving all employees were implemented, establishing machine maintenance standards and using Overall Equipment Effectiveness (OEE) as a performance measure. After these improvements, OEE increased from 85.65% to 92.18%, availability rose from 92.06% to 97.70%, and performance rate increased from 95.85% to 96.00%. The number of defects in code A22 decreased from 223 to 51 pieces, reducing the loss from 88,414.40 Baht to 20,220.33 Baht. Overall, LINE B defects dropped from 765 to 223 pieces, cutting waste loss from 303,305.02 Baht to 88,414.40 Baht. This reduced the total production loss from 1,631,908.11 Baht to 1,013,198.82 Baht, a 36.98% decrease.