Hydrocarbon Processing - October 2021 - GP-31
TURBOMACHINERY
Several major preventative maintenance inspections should
be performed:
1. Lube oil should be checked every 3 mos-6 mos.
Oil sampling should be performed to ensure there
is no breakdown in the integrity of the lube oil
or presence of contaminants that could affect the
performance and efficiency of the turboexpander.
2. Routine readings should be documented for
operating conditions, processing gases and seal gas
to ensure that the turboexpander is operating within
engineering design ranges (as previously noted).
3. Critical checks include:
a. Seal gas differential pressure
b. Thrust pressure and differential pressure
instruments
c. Lube oil differential pressure
(oil-bearing systems)
d. Lube oil supply and drain temperatures
(oil-bearing systems)
e. Lube oil viscosity (oil-bearing systems)
f. Lube oil filter differential pressure
(oil-bearing systems)
g. Reservoir oil level (oil-bearing systems)
h. Auxiliary lube oil pump test
(oil-bearing systems)
4. Replace HMI battery every 2 yr
5. Filters should be replaced as they become clogged
Issue
over time, usually indicated by high differential
pressure across the filters.
Even following the best preventative maintenance programs,
and often as a result of multiple contributing factors,
unscheduled maintenance may eventually be required.
TABLE 1 summarizes typical problem indicators and onsite
troubleshooting measures to be performed.
To provide some perspective, the rotating element may
spin from 8,000 rpm to 80,000 rpm, and the gaps (or clearances)
with the stationary components (bearings, seals and
wheels) are often on the order of just a few thousands of an
inch. When an issue or upset causes one part to contact another
and is damaged, multiple other parts are also affected
and become damaged very quickly.
If a problem leads to a shutdown situation, then users
can minimize downtime by having a complete spare MCS
and complete spare IGV assembly on hand. Swapping the
MCS will typically require a downtime of 3 d-5 d, whereas
ordering emergency spare parts can take up to several weeks
to manufacture and deliver. It is preferable to refrain from
swapping out individual MCS or IGV spare parts in the field
unless the work can be performed by a qualified technician
with proper experience with these machines. Multiple critical
clearances, torques, assembly techniques and other standard
measurements must be followed with significantly tight tolerances.
One missed clearance can easily destroy many major
internal parts within seconds.
TABLE 1. Problem indicators and onsite troubleshooting measures for turboexpanders
Possible causes
Low seal gas
differential
Low supply pressure
Higher than design expander outlet pressure
or wheel pressure
Plugged seal gas filter
Defective or incorrectly set seal gas
differential regulator
Low oil pressure
differential
Low oil level in reservoir
Oil viscosity low
Plugged oil filter
Oil temperature too high
Mechanical damage
High oil temperatures
Oil temperature controller issue
Higher thrust loads
High ambient temperature
Fouled air cooler
Expander will not start
IGVs not fully closed
Compressor inlet valve not fully opening
Faulty expander trip valve
Remote shutdown not cleared
High thrust differential
Operating outside design conditions
Faulty/stuck automatic thrust balance (ATB) valve
Damaged bearings/seals
Incorrect setpoints
Possible solutions
Increase setting of supply regulator
Correct process conditions
Change filter element
Replace or rebuild the differential pressure regulator
or adjust setpoint
Fill reservoir as required
Change oil with new charge and ascertain cause of dilution
Switch filters or replace with new element
Investigate malfunctioning oil cooler
Intrusive investigation
Check oil level and viscosity
Confirm thrust loads
Confirm that lube oil temperature control valve and
oil cooler are working properly
Set IGVs at 0% closed
Investigate limit switch or valve malfunction
Investigate valve wiring or solenoid/air supply
Reset remote shutdown
Correct operational parameters
Overhaul valve and actuator
Intrusive investigation
Correct setpoints in HMI
Gas Processing & LNG | SEPTEMBER/OCTOBER 2021 31
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/refining_processes_handbook_2020
https://www.nxtbook.com/nxtbooks/gulfpub/refining_processes_handbook_2020_v2
https://www.nxtbook.com/nxtbooks/gulfpub/hp_202007
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https://www.nxtbook.com/nxtbooks/gulfpub/hpimarket_2020_v2
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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_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
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