Page 581 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

Be st Practice 1 0.11 The Post-Shipment Phase: Installation, Pre-Commissioning, Commissioning and Start-up Best Practices
Vector filters Bearing oil temperature rise at each bearing
Amplifier(s) Bearing pad temperature (axial and radial) at each
Spectrum analyzer point (if applicable)
Tape recorder or information gathering module Turbine speed
- ‘Walk’ all steam inlet, extraction and exhaust lines. Axial shaft displacement
Confirm all spring hangers are released (unlocked) and Turbine exhaust temperature
safety valves are installed Note: Use shop test data for comparison
II Test procedure - After confirming stable operation at minimum governor
- Confirm all auxiliary systems are operational and at speed, accelerate carefully to overspeed trip setting and
proper conditions (lined out): trip the turbine three times. Each trip speed should fall
Lube/control oil system within the vendors’ trip speed set point allowable range
Governor/trip system - Return to minimum governor speed and confirm
Turning gear (if applicable) satisfactory manual and automatic speed control. Also
All warming lines drained and operational confirm automatic transfer from main to backup governor
Condensing system including condensate pumps (if - Connect vibration recording instruments, reduce turbine
applicable) speed to 500 rpm and record shaft vibration (at each
Extraction system (if applicable) vibration monitoring point) and phase angle while
Steam seal system gradually increasing speed to maximum continuous
Condition monitoring systems (vibration, speed. Repeat step in reverse direction (maximum
temperature, etc.) continuous speed to 500 rpm)
Steam conditions within allowable vendor limits - Note: This data will be reduced to Bode, Nyquist and
- Slow roll and start unit per vendors instructions. (Refer Cascade plots and should be compared to shop test data.
to cold start-up speed vs. time chart) - Increase turbine speed to maximum continuous speed and
- Demonstrate manual trip (panic button) at low speed runforfour(4)hoursoruntilbearingtemperaturesstabilize
(500 rpm) - Finally trip the turbine using a system trip switch
- Reset trip, accelerate back to desired speed e listen for (simulate low oil pressure, etc.)
rubs, etc. III Corrective action
- Gradually increase speed to next speed step. Record the - Failure to meet any requirement in Section II requires
following data for each vendor required speed step up to corrective action and retest
minimum governor speed: - Specifically note any corrective action
Overall vibration at each vibration point (record - Sign off equipment as acceptable to operate
frequency if specified limits are exceeded)

Best Practice 10.11

Obtain a CCM (component condition monitoring) initial Lessons Learned
start-up baseline for critical machinery trains. Failure to obtain detailed component baseline conditions
This is done by obtaining information concerning the condition of for critical machinery trains will lead to extended periods
the following train components: taken up with obtaining additional information to de-
Rotor (performance information) termine the root causes of machinery component param-
Journal bearings
eter changes, with the results being reduced machinery
Thrust bearings
safety and reliability and corresponding revenue losses.
Seals
Many site root cause analyses are inconclusive and need to obtain
Auxiliary systems
additional ‘baseline’ information after failed or worn components are
Machinery condition monitoring using the CCM approach en-
replaced. If ‘baseline’ conditions at initial start-up had been obtained,
sures total monitoring of each major component in the machinery
root causes could have been immediately determined.
train (see the supporting information below for complete CCM
details). Benchmarks
We recommend that all parameters for each monitored component
be obtained from the plant process information system and down- This best practice has been recommended since the late 1980s for all
loaded to Excel spreadsheets. This will allow simultaneous trending of new projects and during all site machinery reliability audits to enable
each component parameter to enable rapid interpretation of a condi- site machinery specialists to immediately identify component param-
tion change in any component for prompt corrective action. We have eter abnormal conditions. This information can then be discussed with
included examples of CCM Excel spreadsheets in the supporting operations to plan for appropriate process changes while attempting to
material for this best practice. extend any required maintenance to a planned shutdown.
552