Abstract:
The objective of this work was to reduce fraction detective of Flange Nuts due
to thread damage. The amount of thread damage was 50.10 percents of the whole
defectives of 4.15 percents. According to careful analysis, six factors that affect the
number of the damage were (1) the revolution of rough turning, (2) the feed rate of
rough cutting tool, (3) the revolution of fine turning, (4) the feed rate of fine cutting
tool (5) the revolution of thread cutting tool and (6) the depth of thread cutting. So
26-1fractional factorial experimental design was used with the confidential interval of
95 percents. The experiments were carried out with 32 runs and 2,400 replications.
The experimental results indicated that all of the factors affected the thread damage
significantly (p<0.05T). The combination of factors that save the minimum number of
thread damage were 2,000 rpm, 0.1 m/min, 4,500 rpm, 0.05 m/min, 2,500 rpm and 0.05
mm/revolution, respectively. As a result, the thread damage accordin3 these setting
was 1.11 percents of the whole fraction defective of 2.07 percents. Therefore, the
whole defective was reduced approximately 46.62 percents, and the factory could
reduce the loss of around 8 284,861 annually.