Page 575 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

Be st Practice 1 0.8 The Post-Shipment Phase: Installation, Pre-Commissioning, Commissioning and Start-up Best Practices
II Test procedure II Test procedure
- Take required action to put system in ‘run’ mode - Confirm all auxiliary systems are operational and at
- Open trip and throttle valve only after ensuring the main proper conditions (lined out)
steam block valve is closed - Lube/control oil system
- Simulate turbine start, slow roll and any start sequence - Governor/trip system
‘hold’ points up to minimum governor operating point - Turning gear (if applicable)
- Confirm proper operation of ‘raise’ and ‘lower’ speed - All warming lines drained and operational
buttons - Condensing system including condensate pumps (if
- Connect external process signal inputs (one at a time) and applicable)
confirm proper governor action to input signal variation - Extraction system (if applicable)
- Check overspeed override feature - Steam seal system
- Confirm automatic transfer to and from backup governor - Conditionmonitoringsystems(vibration,temperature,etc.)
‘position control’ for each of the following cases: - Steam conditions within allowable vendor limits
Loss of main governor power supply - Slow roll and start unit per vendor’s instructions. (refer to
Zero external input signal cold start-up speed vs. time chart)
Failure of ‘final driver’ (internal governor component) - Demonstrate manual trip (panic button) at low speed
Zero speed inputs (500 rpm)
- Confirm manual transfer to and from backup governor - Reset trip, accelerate back to desired speed e listen for
and ‘emergency override’ rubs, etc.
- Check raise and lower speed controls while in backup - Gradually increase speed to next speed step. Record the
governor mode following data for each vendor required speed step up to
- Confirm governor shutdown (trip) operation under the minimum governor speed
following conditions: - Overall vibration at each vibration point (record
Overspeed setting frequency if specified limits are exceeded)
Failure of both main and backup governor controls - Bearing oil temperature rise at each bearing
III Corrective action - Bearing pad temperature (axial and radial) at each point
- Failure to meet any requirement in Section II requires (if applicable)
corrective action and retest - Turbine speed
- Specifically note corrective action - Axial shaft displacement
- Sign off procedure as acceptable to operate - Turbine exhaust temperature
Note: Use shop test data for comparison
- After confirming stable operation at minimum governor
Steam turbine solo run functional test
speed, accelerate carefully to overspeed trip setting
procedure outline and trip the turbine three times. Each trip speed
should fall within the vendor’s trip speed set point
Objective: To confirm acceptable mechanical operation of the allowable range
steam turbine, governor system and safety (trip) - Return to minimum governor speed and confirm
system satisfactory manual and automatic speed control. Also
Procedure Detail each test requirement. Specifically note
confirm automatic transfer from main to backup governor
Format: required test limits (Note: shop test data should be
- Connect vibration recording instruments, reduce turbine
used to define acceptable limits). Record actual test
values using appropriate instrumentation and note all speed to 500 rpm and record shaft vibration (at each
modifications made. vibration monitoring point) and phase angle while
gradually increasing speed to maximum continuous
speed. Repeat step in reverse direction (maximum
I Preparation
- Confirm all auxiliary system tests are complete continuous speed to 500 rpm)
- Note: This data will be reduced to Bode, Nyquist and
(governor, lube system, etc.)
- Confirm all inlet steam lines have been cleaned and Cascade plots and should be compared to shop test data.
- Increase turbine speed to maximum continuous speed
signed off
- Confirm all installed instrumentation is calibrated and run for four (4) hours or until bearing temperatures
- Secure all required instruments stabilize
- Calibrated pressure and temperature gauges - Finally trip the turbine using a system trip switch
- Occiloscope(s) (simulate low oil pressure, etc.)
- Vector filters III Corrective action
- Amplifier(s) - Failure to meet any requirement in Section II requires
- Spectrum analyzer corrective action and retest
- Tape recorder or information gathering module - Specifically note any corrective action
- ‘Walk’ all steam inlet, extraction and exhaust lines. - Sign off equipment as acceptable to operate
Confirm all spring hangers are released (unlocked) and - Typical initial field functional lube/seal system test
procedure baseline document
safety valves are installed

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