Hydrocarbon Processing - October 2021 - GP-28

TURBOMACHINERY
6. Cracked blades due to
mechanical fatigue.
Findings No. 1 through No. 5 are usually
repairable depending on the severity
of the damage and the judgement of the
repair engineer. For instance, FOD on
the blades can be dressed and blended
by hand. Aluminum alloy wheels can be
hard anodized or shot peened to increase
resistance to wear, corrosion or cracking.
In the case of finding No. 5, labyFIG.
3. Mechanical center section detail. Image courtesy of L.A. Turbine.
rinth seal rub damage on the wheel can
sometimes be recovered by mechanically
lifting the seal tip in a lathe and remachining
to reclaim design tolerances.
The expander wheel back seals are often
coated with a soft metal like babbitt, which is abradable. As
part of the repair, it is customary to remove the layer of coating,
reapply it and re-machine to design specifications. This
allows the wheel to be salvaged without compromising its performance.
For any of these repair options, the wheel must be
rebalanced per OEM specifications.
Cracked wheels are not uncommon, and a root cause failure
FIG. 4. Wheel with extensive corrosion damage.
Wheels. Wheels are usually computer numerical control
(CNC)-milled from a forging, either high-strength aluminum
or titanium in some applications. They can be hard anodized
or shot peened for additional protection against corrosion.
The wheels can be mounted onto the shaft in a variety of
ways, namely, keyed cylindrical or tapered bores, or keyless
polygon fits, to name a few. Each wheel can be fastened to
the shaft with a high-strength screw bolted onto an internal
thread in the shaft. Another common design solution features
a hollow shaft with a through-bolt that secures both wheels
with end nuts.
The large rotating components are balanced individually
first, and later put together as an assembly and balance checked,
per the applicable section in API 617. This allows the wheels
to be interchanged in the field without having to send the MCS
to the shop for a rebalance. However, for some applications,
OEMs specify that the rotor be balanced as an assembly and
the parts match-marked, in which case the wheels cannot be
replaced without a full rotor rebalance.
From a shop inspection perspective, some of the most common
findings on wheels include:
1. Wear and/or corrosion to the blade surfaces
2. Dings to the blades due to foreign object damage (FOD)
3. Bent blade tips due to FOD or an
error in installation/shipping

http://www.GasProcessingNews.com

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
Hydrocarbon Processing - October 2021 - 22
Hydrocarbon Processing - October 2021 - 23
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
Hydrocarbon Processing - October 2021 - 75
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
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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_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
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202004
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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
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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
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201811
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201809
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https://www.nxtbook.com/nxtbooks/gulfpub/hp_201804
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