Hydrocarbon Processing - April 2022 - GP-38
MAINTENANCE/LEAK DETECTION
to have caused the high outer
seal temperature, which hardened
and broke the outer seal, mating
ring O-ring shown in FIG. 3.
This resulted in the failure of
the outer seal, which is supported
by the reduction in the NDE
seal cavity pressure from
25 psig to 2 psig (FIG. 2).
3. During the operation of Unit A,
the pump casing was at a
suction pressure of ~200
psig. However, the pressure
measurements show that the
pump pressure dropped from
200 psig to 5 psig during the
8 hr after the pump shutdown, as
shown in FIG. 1. This is believed to
be caused by a failure of the NDE
inner seal due to hang-up, seal
faces wear and/or the presence of
dirt between the two seal faces.
Sour condensate NGL export pumps
frequent seal failures. A design assessment
was completed for the pump
system from the suction column to the
pump discharge and for the seal auxiliary
system to identify any potential
design concerns. In addition, the PI process
data were analyzed to determine the
pump operating conditions. The main
points that may have caused the low reliability
of the seal are listed here:
1. The pump suction line has
a permanent strainer with a
maximum allowable differential
pressure of 0.5 psi. The piping
and instrumentation diagram
(P&ID) shows that the available
net positive suction head
available (NPSHA) and the
net positive suction head
required (NPSHR) are close;
therefore, the use of suction
strainer is not recommended.
2. The pump process data showed
that the pumps were operating
at a higher differential pressure
than the design, as shown in
FIG. 4. This was believed to be
caused by a higher liquid
specific gravity.
FIG. 2. DE and NDE seal leak pressure measurements.
3. The pumps were consistently
operated between 450 gal/min
and 900 gal/min (FIG. 4). As the
pumps have a best efficiency
point (BEP) of ~1,080 gal/min,
the pumps were operated for a
long time outside the preferred
operating region, which ranges
from 750 gal/min-1,300 gal/
min. This resulted in high flow
FIG. 3. The outboard mating ring showed heavy contamination and the O-ring was hardened and broken (A and B); the inboard primary dynamic
ring showed excessive wear and OD chipping and contamination (C).
38 MARCH/APRIL 2022 | GasProcessingNews.com
http://www.GasProcessingNews.com
Hydrocarbon Processing - April 2022
Table of Contents for the Digital Edition of Hydrocarbon Processing - April 2022
Contents
Hydrocarbon Processing - April 2022 - Cover1
Hydrocarbon Processing - April 2022 - Cover2
Hydrocarbon Processing - April 2022 - Contents
Hydrocarbon Processing - April 2022 - 4
Hydrocarbon Processing - April 2022 - 5
Hydrocarbon Processing - April 2022 - 6
Hydrocarbon Processing - April 2022 - 7
Hydrocarbon Processing - April 2022 - 8
Hydrocarbon Processing - April 2022 - 9
Hydrocarbon Processing - April 2022 - 10
Hydrocarbon Processing - April 2022 - 11
Hydrocarbon Processing - April 2022 - 12
Hydrocarbon Processing - April 2022 - 13
Hydrocarbon Processing - April 2022 - 14
Hydrocarbon Processing - April 2022 - 15
Hydrocarbon Processing - April 2022 - 16
Hydrocarbon Processing - April 2022 - 17
Hydrocarbon Processing - April 2022 - 18
Hydrocarbon Processing - April 2022 - 19
Hydrocarbon Processing - April 2022 - 20
Hydrocarbon Processing - April 2022 - 21
Hydrocarbon Processing - April 2022 - 22
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Hydrocarbon Processing - April 2022 - 24
Hydrocarbon Processing - April 2022 - 25
Hydrocarbon Processing - April 2022 - 26
Hydrocarbon Processing - April 2022 - 27
Hydrocarbon Processing - April 2022 - 28
Hydrocarbon Processing - April 2022 - 29
Hydrocarbon Processing - April 2022 - 30
Hydrocarbon Processing - April 2022 - 31
Hydrocarbon Processing - April 2022 - 32
Hydrocarbon Processing - April 2022 - 33
Hydrocarbon Processing - April 2022 - 34
Hydrocarbon Processing - April 2022 - 35
Hydrocarbon Processing - April 2022 - 36
Hydrocarbon Processing - April 2022 - 37
Hydrocarbon Processing - April 2022 - 38
Hydrocarbon Processing - April 2022 - 39
Hydrocarbon Processing - April 2022 - 40
Hydrocarbon Processing - April 2022 - 41
Hydrocarbon Processing - April 2022 - 42
Hydrocarbon Processing - April 2022 - 43
Hydrocarbon Processing - April 2022 - 44
Hydrocarbon Processing - April 2022 - 45
Hydrocarbon Processing - April 2022 - 46
Hydrocarbon Processing - April 2022 - 47
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Hydrocarbon Processing - April 2022 - 49
Hydrocarbon Processing - April 2022 - 50
Hydrocarbon Processing - April 2022 - 51
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Hydrocarbon Processing - April 2022 - 53
Hydrocarbon Processing - April 2022 - 54
Hydrocarbon Processing - April 2022 - 55
Hydrocarbon Processing - April 2022 - 56
Hydrocarbon Processing - April 2022 - 57
Hydrocarbon Processing - April 2022 - 58
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Hydrocarbon Processing - April 2022 - 60
Hydrocarbon Processing - April 2022 - 61
Hydrocarbon Processing - April 2022 - 62
Hydrocarbon Processing - April 2022 - 63
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Hydrocarbon Processing - April 2022 - 65
Hydrocarbon Processing - April 2022 - 66
Hydrocarbon Processing - April 2022 - 67
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Hydrocarbon Processing - April 2022 - 69
Hydrocarbon Processing - April 2022 - 70
Hydrocarbon Processing - April 2022 - 71
Hydrocarbon Processing - April 2022 - 72
Hydrocarbon Processing - April 2022 - 73
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Hydrocarbon Processing - April 2022 - 76
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Hydrocarbon Processing - April 2022 - 81
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Hydrocarbon Processing - April 2022 - 84
Hydrocarbon Processing - April 2022 - 85
Hydrocarbon Processing - April 2022 - 86
Hydrocarbon Processing - April 2022 - 87
Hydrocarbon Processing - April 2022 - 88
Hydrocarbon Processing - April 2022 - 88A
Hydrocarbon Processing - April 2022 - 88B
Hydrocarbon Processing - April 2022 - 89
Hydrocarbon Processing - April 2022 - 90
Hydrocarbon Processing - April 2022 - Cover3
Hydrocarbon Processing - April 2022 - Cover4
Hydrocarbon Processing - April 2022 - GP-1
Hydrocarbon Processing - April 2022 - GP-2
Hydrocarbon Processing - April 2022 - GP-3
Hydrocarbon Processing - April 2022 - GP-4
Hydrocarbon Processing - April 2022 - GP-5
Hydrocarbon Processing - April 2022 - GP-6
Hydrocarbon Processing - April 2022 - GP-7
Hydrocarbon Processing - April 2022 - GP-8
Hydrocarbon Processing - April 2022 - GP-9
Hydrocarbon Processing - April 2022 - GP-10
Hydrocarbon Processing - April 2022 - GP-11
Hydrocarbon Processing - April 2022 - GP-12
Hydrocarbon Processing - April 2022 - GP-13
Hydrocarbon Processing - April 2022 - GP-14
Hydrocarbon Processing - April 2022 - GP-15
Hydrocarbon Processing - April 2022 - GP-16
Hydrocarbon Processing - April 2022 - GP-17
Hydrocarbon Processing - April 2022 - GP-18
Hydrocarbon Processing - April 2022 - GP-19
Hydrocarbon Processing - April 2022 - GP-20
Hydrocarbon Processing - April 2022 - GP-21
Hydrocarbon Processing - April 2022 - GP-22
Hydrocarbon Processing - April 2022 - GP-23
Hydrocarbon Processing - April 2022 - GP-24
Hydrocarbon Processing - April 2022 - GP-25
Hydrocarbon Processing - April 2022 - GP-26
Hydrocarbon Processing - April 2022 - GP-27
Hydrocarbon Processing - April 2022 - GP-28
Hydrocarbon Processing - April 2022 - GP-29
Hydrocarbon Processing - April 2022 - GP-30
Hydrocarbon Processing - April 2022 - GP-31
Hydrocarbon Processing - April 2022 - GP-32
Hydrocarbon Processing - April 2022 - GP-33
Hydrocarbon Processing - April 2022 - GP-34
Hydrocarbon Processing - April 2022 - GP-35
Hydrocarbon Processing - April 2022 - GP-36
Hydrocarbon Processing - April 2022 - GP-37
Hydrocarbon Processing - April 2022 - GP-38
Hydrocarbon Processing - April 2022 - GP-39
Hydrocarbon Processing - April 2022 - GP-40
Hydrocarbon Processing - April 2022 - GP-41
Hydrocarbon Processing - April 2022 - GP-42
Hydrocarbon Processing - April 2022 - GP-43
Hydrocarbon Processing - April 2022 - GP-44
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