Abstract:
The objective of this research was to reduce number defective products in the
manufacturing process of sanitary ware of CH 410Y model. Output of this product during
October, 2009 - March, 2010 was average of 2,148.5 pieces per month with the number of
defective of 1,164.3 pieces per month. The fraction defective was about 54.2%. According
to this condition, the financial loss was about ฿ 1.6 million per month. The study was
conducted by using Failure Mode and Effect Analysis (FMEA). After the analysis, the
causes of this problem were clay crack with the average number of defectives of 253.8
pieces per month or about 21.8% and poor finish with the average number of defectives of
213.8 pieces per month or about 18.4%. The results of brain storming indicated the
improvement method. They were (1) changing the procedure of slip drainage plugging, (2)
decrease the setting time of the clay plug from 5 hours to 3 hours, and (3) using check
sheet to be able to check-back working procedures. All suggestions had been implemented
at the time. After the improvement, the information on defective items was recorded
between June and September, 2010. The results indicated that the number of defectives
was 42.6% or 11.6% decreased. Also, the loss was reduced to ฿ 1.27 million per month or
20.1% reduction.