Hydrocarbon Processing - December 2021 - 15

Reliability
HEINZ P. BLOCH, RELIABILITY/EQUIPMENT EDITOR
Heinz.Bloch@HydrocarbonProcessing.com
Disregarding storage preservation has consequences
As a rule, equipment to be installed at
a plant site initially arrives at an outdoor
storage yard. FIG. 1 shows a small section
where, on occasion, more than 1,000
items of rotating machinery are stored under
slight oil mist pressure.
Experience shows that of 1,000 machines
stored for 3 yr in this manner, no
more than 60 have ever shown incipient
bearing damage. With ambient air and atmospheric
contaminants excluded, it can
be reasoned that the bearings had slight
damage at assembly or sustained damage
while being transported over roadways
with potholes or on railroads with discontinuities
in the track system. Such discontinuities
can transmit shock loads into the
cargo in the railcars.
Be this as it may, FIG. 2 shows that fully
94% (or an even higher percentage) of the
equipment properly preserved by oil mist
will be ready to run up to 3 yr later without
first having to be dismantled for cleanup.
FIG. 2 also allows us to estimate that
after 3 yr of conventional preservation,
the owners can expect a 20% " infant mortality. "
Equipment arriving at an outside
storage yard for oil mist preservation receives
an oil mist inlet fitting and a drilled
drain plug. Once a small oil mist line is
connected to the inlet fitting, the equipment
can be stored for years of successful
outdoor preservation.
Summary of how oil mist works. Oil
mist will coalesce when atomized droplets
combine to become larger drops of liquid
oil as the equipment operates. Shaft rotation
at operating speed causes turbulent
flow in the bearings; the atomized particles
get knocked together and become
large and heavy. Turbulence is obviously
not created in equipment at standstill.
Since there is then no turbulence, the
reclassifying (conversion) of oil mist to
liquid oil proceeds at a slower rate in nonrunning
equipment. However, since the
oil mist is at a pressure of between 0.1 psi
and 0.3 psi over ambient, it immediately
FIG. 1. Outdoor storage yard. Source: T. F. Hudgins.
fills the bearing housings and other spaces.
Full corrosion protection is, therefore, established
without delay. After a week or so,
all surfaces will show a light coating of oil.
Noteworthy facts include:
* A low-point drain location is
identified and left open at all times.
This low point is useful because
it prevents oil accumulation and
ensures throughflow of a small
amount of mist. The mist lost
through a drain orifice equals the
makeup mist. With rare exceptions,
a 1-mm minimum, 3-mm maximum
drain orifice is all that is needed.
* A machine in storage and ready
for preservation can be slanted
or skewed to create or locate a
convenient and/or accessible lowpoint
drain. A flat pan can be used
to catch this drainage for metering
and proper disposal.
* A rotor blanketed with oil mist
should be manually rotated 2.5
turns every 6 mos. This ensures
that a light coating of oil remains
established throughout a rolling
element bearing and avoids false
brinelling (indentation) at or near
the 6 o'clock load points.
Only steam turbines require special
cleanup before recommissioning. Accordingly,
the following precautions apply
only to steam turbines:
* Use oils with formulations
that will not promote future
stress corrosion cracking.
* Prior to machine commissioning,
blow steam through the equipment.
This removes the thin coating of
oil that would have accumulated
on the surfaces.
* Collect some of the exiting
blowdown steam and observe
if it still contains traces of oil.
Fifty years of oil mist preservation.
Although oil mist preservation has been
used for every successful project at bestin-class
companies and corporations, traHydrocarbon
Processing | DECEMBER 2021 15

Hydrocarbon Processing - December 2021

Table of Contents for the Digital Edition of Hydrocarbon Processing - December 2021

Contents
Hydrocarbon Processing - December 2021 - Cover1
Hydrocarbon Processing - December 2021 - Cover2
Hydrocarbon Processing - December 2021 - Contents
Hydrocarbon Processing - December 2021 - 4
Hydrocarbon Processing - December 2021 - 5
Hydrocarbon Processing - December 2021 - 6
Hydrocarbon Processing - December 2021 - 7
Hydrocarbon Processing - December 2021 - 8
Hydrocarbon Processing - December 2021 - 9
Hydrocarbon Processing - December 2021 - 10
Hydrocarbon Processing - December 2021 - 11
Hydrocarbon Processing - December 2021 - 12
Hydrocarbon Processing - December 2021 - 13
Hydrocarbon Processing - December 2021 - 14
Hydrocarbon Processing - December 2021 - 15
Hydrocarbon Processing - December 2021 - 16
Hydrocarbon Processing - December 2021 - 17
Hydrocarbon Processing - December 2021 - 18
Hydrocarbon Processing - December 2021 - 19
Hydrocarbon Processing - December 2021 - 20
Hydrocarbon Processing - December 2021 - 21
Hydrocarbon Processing - December 2021 - 22
Hydrocarbon Processing - December 2021 - 23
Hydrocarbon Processing - December 2021 - 24
Hydrocarbon Processing - December 2021 - 25
Hydrocarbon Processing - December 2021 - 26
Hydrocarbon Processing - December 2021 - 27
Hydrocarbon Processing - December 2021 - 28
Hydrocarbon Processing - December 2021 - 29
Hydrocarbon Processing - December 2021 - 30
Hydrocarbon Processing - December 2021 - 31
Hydrocarbon Processing - December 2021 - 32
Hydrocarbon Processing - December 2021 - 33
Hydrocarbon Processing - December 2021 - 34
Hydrocarbon Processing - December 2021 - 35
Hydrocarbon Processing - December 2021 - 36
Hydrocarbon Processing - December 2021 - 37
Hydrocarbon Processing - December 2021 - 38
Hydrocarbon Processing - December 2021 - 39
Hydrocarbon Processing - December 2021 - 40
Hydrocarbon Processing - December 2021 - 41
Hydrocarbon Processing - December 2021 - 42
Hydrocarbon Processing - December 2021 - 43
Hydrocarbon Processing - December 2021 - 44
Hydrocarbon Processing - December 2021 - 45
Hydrocarbon Processing - December 2021 - 46
Hydrocarbon Processing - December 2021 - 47
Hydrocarbon Processing - December 2021 - 48
Hydrocarbon Processing - December 2021 - 49
Hydrocarbon Processing - December 2021 - 50
Hydrocarbon Processing - December 2021 - 51
Hydrocarbon Processing - December 2021 - 52
Hydrocarbon Processing - December 2021 - 53
Hydrocarbon Processing - December 2021 - 54
Hydrocarbon Processing - December 2021 - 55
Hydrocarbon Processing - December 2021 - 56
Hydrocarbon Processing - December 2021 - 57
Hydrocarbon Processing - December 2021 - 58
Hydrocarbon Processing - December 2021 - 59
Hydrocarbon Processing - December 2021 - 60
Hydrocarbon Processing - December 2021 - 61
Hydrocarbon Processing - December 2021 - 62
Hydrocarbon Processing - December 2021 - 63
Hydrocarbon Processing - December 2021 - 64
Hydrocarbon Processing - December 2021 - 65
Hydrocarbon Processing - December 2021 - 66
Hydrocarbon Processing - December 2021 - 67
Hydrocarbon Processing - December 2021 - 68
Hydrocarbon Processing - December 2021 - 69
Hydrocarbon Processing - December 2021 - 70
Hydrocarbon Processing - December 2021 - 71
Hydrocarbon Processing - December 2021 - 72
Hydrocarbon Processing - December 2021 - 73
Hydrocarbon Processing - December 2021 - 74
Hydrocarbon Processing - December 2021 - 75
Hydrocarbon Processing - December 2021 - 76
Hydrocarbon Processing - December 2021 - 77
Hydrocarbon Processing - December 2021 - 78
Hydrocarbon Processing - December 2021 - 79
Hydrocarbon Processing - December 2021 - 80
Hydrocarbon Processing - December 2021 - 81
Hydrocarbon Processing - December 2021 - 82
Hydrocarbon Processing - December 2021 - Cover3
Hydrocarbon Processing - December 2021 - Cover4
Hydrocarbon Processing - December 2021 - GP-1
Hydrocarbon Processing - December 2021 - GP-2
Hydrocarbon Processing - December 2021 - GP-3
Hydrocarbon Processing - December 2021 - GP-4
Hydrocarbon Processing - December 2021 - GP-5
Hydrocarbon Processing - December 2021 - GP-6
Hydrocarbon Processing - December 2021 - GP-7
Hydrocarbon Processing - December 2021 - GP-8
Hydrocarbon Processing - December 2021 - GP-9
Hydrocarbon Processing - December 2021 - GP-10
Hydrocarbon Processing - December 2021 - GP-11
Hydrocarbon Processing - December 2021 - GP-12
Hydrocarbon Processing - December 2021 - GP-13
Hydrocarbon Processing - December 2021 - GP-14
Hydrocarbon Processing - December 2021 - GP-15
Hydrocarbon Processing - December 2021 - GP-16
Hydrocarbon Processing - December 2021 - GP-17
Hydrocarbon Processing - December 2021 - GP-18
Hydrocarbon Processing - December 2021 - GP-19
Hydrocarbon Processing - December 2021 - GP-20
Hydrocarbon Processing - December 2021 - GP-21
Hydrocarbon Processing - December 2021 - GP-22
Hydrocarbon Processing - December 2021 - GP-23
Hydrocarbon Processing - December 2021 - GP-24
Hydrocarbon Processing - December 2021 - GP-25
Hydrocarbon Processing - December 2021 - GP-26
Hydrocarbon Processing - December 2021 - GP-27
Hydrocarbon Processing - December 2021 - GP-28
Hydrocarbon Processing - December 2021 - GP-29
Hydrocarbon Processing - December 2021 - GP-30
Hydrocarbon Processing - December 2021 - GP-31
Hydrocarbon Processing - December 2021 - GP-32
Hydrocarbon Processing - December 2021 - GP-33
Hydrocarbon Processing - December 2021 - GP-34
Hydrocarbon Processing - December 2021 - GP-35
Hydrocarbon Processing - December 2021 - GP-36
Hydrocarbon Processing - December 2021 - GP-37
Hydrocarbon Processing - December 2021 - GP-38
Hydrocarbon Processing - December 2021 - GP-39
Hydrocarbon Processing - December 2021 - GP-40
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/gas-processes-handbook-2022_v2
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https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_processes_handbook_2021_v2
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https://www.nxtbook.com/nxtbooks/gulfpub/catalyst_handbook_2020_v2
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202012
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202009
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202008
https://www.nxtbook.com/nxtbooks/gulfpub/refining_processes_handbook_2020
https://www.nxtbook.com/nxtbooks/gulfpub/refining_processes_handbook_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202007
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202006
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202001
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201912
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201911
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2020
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201910
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201909
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201908
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201907
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201902
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201901
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018_v2
https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_2018
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201812
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2019_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2019
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201811
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201810
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201809
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201801
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201712
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201709
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_2017mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201612
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