Reliability Analysis of Car Subsystem by Weibull …
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Table 2 Details of time to failure for clutch system
S. No. of cars
Distance before failure (km)
Time to failure (h)
2
40,100
668.33
5
42,000
700
8
50,000
833.33
11
12,000
200
14
58,000
966.67
Table 3 Median ranks of clutch system
S. No.
Time to failure (hr)
Median ranks (%)
1
200
12.96
2
668.33
31.48
3
700
50
4
833.33
68.52
5
966.67
87.03
Table 4 Calculation table of clutch system
N
t
x = ln(t)
F(t)
y
x 2
y 2
x.y
1
200
5.298
0.1296
−1.97
28.06
3.88
−10.43
2
668.33
6.504
0.3148
−0.97
42.30
0.94
−6.30
3
700
6.551
0.50
−0.36
42.91
0.13
−2.35
4
833.33
6.725
0.6852
+0.14
45.22
0.02
+0.9415
5
966.67
6.873
0.8703
+0.71
47.25
0.504
+4.879
31.95
−2.45
205.74
5.47
−13.259
of the clutch system started after the initial running of 12,000 km and ranges up to
58,000 km for an initial run. Moreover, a new Wagon-R car clutch system failure
ranges from 200–966.67 h of running. Tables 3 and 4 show the different calculation
for reliability analysis.
3.2 Rear Brake System
Figure 2 depicts the graph of distance travelled before failure of rear brake system
for different cars serial number, and Table 5 shows the actual details of distance
travelled with failure time. It is clear from Table 5 rear brakes of car serial number
4 failed at 29,000 km after running of around 483.33 h. For serial number 5 and 7,
the distances and time are 74,000 with 12,333.33 h and 40,000 km with 666.67 h,