Reliability
197
Table 4.1 Machinery plant component failure
rates and mean time
between failures [4.30]
Component
Failure
No. of
Total
Total
per
units
no. of
hours
100,000 Reliability
included failures operation
MTBF hours R=e
-xt
Pumps-main feed
2
Main condste.
2
Aux. condste.
2
Main circ.
2
Aux. circ.
2
Other SW
6
Lube oil
2
FO serv.
2
FO trans.
2
Main boiler
2
Tubes
Refractory
SH tube supports
Safety valves
Soot blowers
Drum desuperheater
Superheat temp.
control
Feed reg. valve
Generators
2
Main turbines
2
Main red. gear
1
DFT
1
HP feed heater
1
LP feed heater
1
FW evaporator
2
Air ejector main
1
Aux.
2
Evap.
2
Condensor-main
1
Aux.
2
Gas air heaters
2
Forced draft blower
2
4
85,680 21,400
4.7
0.7542
4
80,600 20,150
5.0
0.7407
3
85,680 28,600
3.5
0.8104
8
80,600 10,080 10.0
0.5489
7
85,680 12,250
8.2
0.6113
7
51,400
7,340 13.6
0.4421
3
80,600 26,900
3.7
0.8010
2
85,680 42,800
2.3
0.8711
0
13,700 13,700
7.3
0.6452
6
128,400 21,400
4.7
0.7542
14
128,500
9,200 10.9
0.5200
6
128,500 21,400
4.7
0.7542
13
128,500
9,900 10.1
0.5456
17
18,500
7,560 13.2
0.4505
3
128,500 42,900
2.3
0.8711
5
128,500 25,700
3.9
0.7914
9
128,500 14,300
7.0
0.5711
1
171,200 171,200
0.6
0.9646
0
161,200 161,200
0.6
0.9646
1
80,600 80,600
1.2
0.9305
1
85,680 85,680
1.2
0.9305
1
85,680 85,680
1.2
0.9305
0
85,680 85,680
1.2
0.9305
0
85,680 85,680
1.2
0.9305
0
80,600 80,600
1.2
0.9305
0
85,600 85,600
1.2
0.9305
1
80,600 80,600
1.2
0.9305
0
80,600 80,600
1.2
0.9305
0
85,680 85,680
1.2
0.9305
5
128,500 25,700
3.9
0.7914
0
85,680 85,680
1.2
0.9305
*Based on operation for 6000 h.