Hydrocarbon Processing - October 2021 - GP-29

TURBOMACHINERY
When a turboexpander is sent to a shop for inspection, it is
typical to find moderate to heavy wear on the babbitted areas.
The wear can be caused by a number of issues, such as oil contamination
and/or degradation, excessive rotor thrust, system
upsets, etc. From an aftermarket perspective, the scope of repair
involves replacement or reapplication of the babbitt layer,
depending on lead time and cost. For older designs, this opens
an opportunity to consider various design upgrades that make
the bearings more reliable.
Sometimes a failure analysis is warranted. For example,
FIG. 7 shows a case in which oil contamination led to exceedingly
high oil operating temperatures evidenced by bearings
covered in black residue (upper image). In another instance, a
bearing shows damage to the thrust face caused by electrical
sparking during operation (lower image).
Shafts. Shafts are designed to have some protection in the
bearing location with chrome plating, high-velocity oxygen
fuel (HVOF) tungsten carbide, or even dry film lubricant.
These protective measures provide a barrier between the bearing
and the shaft base material. Operational problems with the
bearings and the seals often lead to some degree of wear or
damage in the shaft. The most common is wear or rub damage
in the bearing or seal areas. Many times, shafts can be easily
repaired by reapplying the coating.
AMBs are common in the petrochemical industry. These
bearings require a high-speed, five-axis controller that maintains
the rotor in a stable orbit. From a shop repair perspective,
AMBs are typically serviced at the bearing OEM due to their
complexity. OEMs will perform a thorough mechanical and
electrical evaluation and formulate a scope of work.
Seals. Shaft seals are placed on both sides of the machine
and are typically single-port, non-contacting labyrinth seals.
The labyrinth teeth can be located on either the stationary
portion of the seal or on the rotating shaft. The seal on the
expander end is incorporated into the so-called " heat barrier
FIG. 5. Turboexpander equipped with active magnetic bearings. Image
courtesy of L.A. Turbine.
FIG. 6. Bearing options. Images (center and right) courtesy of
Waukesha Bearings.
FIG. 7. Oil bearing damage.
Gas Processing & LNG | SEPTEMBER/OCTOBER 2021 29

Hydrocarbon Processing - October 2021

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

Contents
Hydrocarbon Processing - October 2021 - Cover1
Hydrocarbon Processing - October 2021 - Cover2
Hydrocarbon Processing - October 2021 - Contents
Hydrocarbon Processing - October 2021 - 4
Hydrocarbon Processing - October 2021 - 5
Hydrocarbon Processing - October 2021 - 6
Hydrocarbon Processing - October 2021 - 7
Hydrocarbon Processing - October 2021 - 8
Hydrocarbon Processing - October 2021 - 9
Hydrocarbon Processing - October 2021 - 10
Hydrocarbon Processing - October 2021 - 11
Hydrocarbon Processing - October 2021 - 12
Hydrocarbon Processing - October 2021 - 13
Hydrocarbon Processing - October 2021 - 14
Hydrocarbon Processing - October 2021 - 15
Hydrocarbon Processing - October 2021 - 16
Hydrocarbon Processing - October 2021 - 17
Hydrocarbon Processing - October 2021 - 18
Hydrocarbon Processing - October 2021 - 19
Hydrocarbon Processing - October 2021 - 20
Hydrocarbon Processing - October 2021 - 21
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Hydrocarbon Processing - October 2021 - 24
Hydrocarbon Processing - October 2021 - 25
Hydrocarbon Processing - October 2021 - 26
Hydrocarbon Processing - October 2021 - 27
Hydrocarbon Processing - October 2021 - 28
Hydrocarbon Processing - October 2021 - 29
Hydrocarbon Processing - October 2021 - 30
Hydrocarbon Processing - October 2021 - 31
Hydrocarbon Processing - October 2021 - 32
Hydrocarbon Processing - October 2021 - 33
Hydrocarbon Processing - October 2021 - 34
Hydrocarbon Processing - October 2021 - 35
Hydrocarbon Processing - October 2021 - 36
Hydrocarbon Processing - October 2021 - 37
Hydrocarbon Processing - October 2021 - 38
Hydrocarbon Processing - October 2021 - 39
Hydrocarbon Processing - October 2021 - 40
Hydrocarbon Processing - October 2021 - 41
Hydrocarbon Processing - October 2021 - 42
Hydrocarbon Processing - October 2021 - 43
Hydrocarbon Processing - October 2021 - 44
Hydrocarbon Processing - October 2021 - 45
Hydrocarbon Processing - October 2021 - 46
Hydrocarbon Processing - October 2021 - 47
Hydrocarbon Processing - October 2021 - 48
Hydrocarbon Processing - October 2021 - 49
Hydrocarbon Processing - October 2021 - 50
Hydrocarbon Processing - October 2021 - 51
Hydrocarbon Processing - October 2021 - 52
Hydrocarbon Processing - October 2021 - 53
Hydrocarbon Processing - October 2021 - 54
Hydrocarbon Processing - October 2021 - 55
Hydrocarbon Processing - October 2021 - 56
Hydrocarbon Processing - October 2021 - 57
Hydrocarbon Processing - October 2021 - 58
Hydrocarbon Processing - October 2021 - 59
Hydrocarbon Processing - October 2021 - 60
Hydrocarbon Processing - October 2021 - 61
Hydrocarbon Processing - October 2021 - 62
Hydrocarbon Processing - October 2021 - 63
Hydrocarbon Processing - October 2021 - 64
Hydrocarbon Processing - October 2021 - 65
Hydrocarbon Processing - October 2021 - 66
Hydrocarbon Processing - October 2021 - 67
Hydrocarbon Processing - October 2021 - 68
Hydrocarbon Processing - October 2021 - 69
Hydrocarbon Processing - October 2021 - 70
Hydrocarbon Processing - October 2021 - 71
Hydrocarbon Processing - October 2021 - 72
Hydrocarbon Processing - October 2021 - 73
Hydrocarbon Processing - October 2021 - 74
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Hydrocarbon Processing - October 2021 - 76
Hydrocarbon Processing - October 2021 - 77
Hydrocarbon Processing - October 2021 - 78
Hydrocarbon Processing - October 2021 - 79
Hydrocarbon Processing - October 2021 - 80
Hydrocarbon Processing - October 2021 - 81
Hydrocarbon Processing - October 2021 - 82
Hydrocarbon Processing - October 2021 - 83
Hydrocarbon Processing - October 2021 - 84
Hydrocarbon Processing - October 2021 - 85
Hydrocarbon Processing - October 2021 - 86
Hydrocarbon Processing - October 2021 - 87
Hydrocarbon Processing - October 2021 - 88
Hydrocarbon Processing - October 2021 - 89
Hydrocarbon Processing - October 2021 - 90
Hydrocarbon Processing - October 2021 - Cover3
Hydrocarbon Processing - October 2021 - Cover4
Hydrocarbon Processing - October 2021 - GP-1
Hydrocarbon Processing - October 2021 - GP-2
Hydrocarbon Processing - October 2021 - GP-3
Hydrocarbon Processing - October 2021 - GP-4
Hydrocarbon Processing - October 2021 - GP-5
Hydrocarbon Processing - October 2021 - GP-6
Hydrocarbon Processing - October 2021 - GP-7
Hydrocarbon Processing - October 2021 - GP-8
Hydrocarbon Processing - October 2021 - GP-9
Hydrocarbon Processing - October 2021 - GP-10
Hydrocarbon Processing - October 2021 - GP-11
Hydrocarbon Processing - October 2021 - GP-12
Hydrocarbon Processing - October 2021 - GP-13
Hydrocarbon Processing - October 2021 - GP-14
Hydrocarbon Processing - October 2021 - GP-15
Hydrocarbon Processing - October 2021 - GP-16
Hydrocarbon Processing - October 2021 - GP-17
Hydrocarbon Processing - October 2021 - GP-18
Hydrocarbon Processing - October 2021 - GP-19
Hydrocarbon Processing - October 2021 - GP-20
Hydrocarbon Processing - October 2021 - GP-21
Hydrocarbon Processing - October 2021 - GP-22
Hydrocarbon Processing - October 2021 - GP-23
Hydrocarbon Processing - October 2021 - GP-24
Hydrocarbon Processing - October 2021 - GP-25
Hydrocarbon Processing - October 2021 - GP-26
Hydrocarbon Processing - October 2021 - GP-27
Hydrocarbon Processing - October 2021 - GP-28
Hydrocarbon Processing - October 2021 - GP-29
Hydrocarbon Processing - October 2021 - GP-30
Hydrocarbon Processing - October 2021 - GP-31
Hydrocarbon Processing - October 2021 - GP-32
Hydrocarbon Processing - October 2021 - GP-33
Hydrocarbon Processing - October 2021 - GP-34
Hydrocarbon Processing - October 2021 - GP-35
Hydrocarbon Processing - October 2021 - GP-36
Hydrocarbon Processing - October 2021 - GP-37
Hydrocarbon Processing - October 2021 - GP-38
Hydrocarbon Processing - October 2021 - GP-39
Hydrocarbon Processing - October 2021 - GP-40
Hydrocarbon Processing - October 2021 - GP-41
Hydrocarbon Processing - October 2021 - GP-42
Hydrocarbon Processing - October 2021 - GP-43
Hydrocarbon Processing - October 2021 - GP-44
https://www.nxtbook.com/gulfenergyinfo/gulfpub/HPI-Market-Data-2023-v3
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2024
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/gas-processes-handbook-2022
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202212
https://www.nxtbook.com/gulfenergyinfo/gulfpub/hpi-market-data-2023-v2
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https://www.nxtbook.com/gulfenergyinfo/gulfpub/hp_202211
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https://www.nxtbook.com/nxtbooks/gulfpub/petrochemical_processes_handbook_2021
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202107
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_ebooks
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202103
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_202101
https://www.nxtbook.com/nxtbooks/gulfpub/catalyst_handbook_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/catalyst_handbook_2020
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202012
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202011
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https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2021
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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202005
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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
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201905
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201903
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_201806
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201804
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201802
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201801
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201712
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201711
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201710
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201709
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201708
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201707
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201706
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201705
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201704
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201703
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201702
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201701
https://www.nxtbook.com/nxtbooks/gulfpub/hp_2017mediaplanner
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201612
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201611
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201610
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201609
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201608
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201607
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201601
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201512
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201107_srsguide
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201107
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201106
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201105
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201104
https://www.nxtbook.com/nxtbooks/gulfpub/hp_201103
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