Research Article

Development of Automatic Equipment for Washing and Nondestructive Inspection of Stud Bolt

Table 5

Analysis of variance.
(a) Analysis of variance for S-N ratios

LevelS-N ratio
Washing liquid injection pressureAir injection pressureRotational speed of brush shaftWashing time

138.72 (2 bar)38.82 (3 bar)37.63 (90 rpm)38.23 (5 s)
238.98 (3 bar)38.88 (5 bar)39.12 (180 rpm)39.03 (15 s)
338.62 (5 bar)38.63 (7 bar)39.58 (360 rpm)39.07 (30 s)
Variance0.040.021.040.23
Rank3412

(b) Analysis of variance for responses

LevelResponse
Washing liquid injection pressureAir injection pressureRotational speed of brush shaftWashing time

187.10 (2 bar)88.13 (3 bar)76.23 (90 rpm)82.00 (5 s)
289.27 (3 bar)88.23 (5 bar)90.57 (180 rpm)89.77 (15 s)
385.70 (5 bar)85.70 (7 bar)95.27 (360 rpm)90.30 (30 s)
Variance3.242.0598.3721.60
Rank3412