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Component: Production wing valve
Failure rate
(10 -6 /hours)
Reliability data dossier
Failure mode
Data source/comment
4.57 All All failures of gate valves are
calculated with a MTBF of 25 years,
personal conversation with Marvin
Rausand [19].
2.23
1.67
LCP: 21.76%
ITL: 14.74%
EXL: 12.26%
=48.70%
LCP: 21.76%
ITL: 14.74%
=36.50%
0.56 EXL: 12.26%
Recommended values for calculations:
Failure rate (10 -6 /hrs):
LCP, ITL, EXL: 2.2
LCP, ITL: 1.7
EXL: 0.6
Failures regarding leakage through
the valve and external leakage.
The distribution of failure modes is
according to those of gate valves
in OREDA 97, p 348.
Failures regarding leakage through
the valve. The distribution of
failure modes is according to those
of gate valves in OREDA 97, p 348.
Failures regarding leakage to the
surroundings. The distribution of
failure modes is according to those
of gate valves in OREDA 97, p 348.
Testing and maintenance:
The production wing valve is tested every 6 months and repaired if failure is detected
Comments and leakage paths:
The external leakage is to the surroundings through the material of the valve, the actuator or the
seals. The LPC and FTC failures provide a leakage path trough the wing valve and out of the x-mas
tree.
D-6