Page 600 - Subyek Teknik Mesin - Forsthoffers Best Practice Handbook for Rotating Machinery by William E Forsthoffer

Be st Practice 1 1.7 Preventive and Predictive Maintenance Best Practices
installed and set. If its calibration is not periodically checked, it 2. Absence of cavitation
could cause an unnecessary shutdown of equipment and result 3. Pump and driver acceptable bearing temperature
in this revenue loss. 4. Driver governor and safety checks (uncoupled) if driver is
a steam turbine
Functional lube/seal system test procedure outline
C. Auxiliary pump unit
Same procedure as item B above.
Objective: To confirm proper functional operation of the entire D. Relief valve set point and non-chatter check
system prior to equipment start-up
E. Operate main pump unit and confirm all pressures,
Procedure Detail each test requirement. Specifically note
format: required functions/set points of each component. differential pressures, temperatures and flows are as
Record actual functions/set points and all specified on the system schematic and/or Bill of material
modifications made. F. Confirm proper accumulator pre-charge (if applicable)
Note: All testing to be performed without the unit in G. Confirm proper set point annunciation and/or action of
operation. all pressure, differential pressure and temperature switches.
H. Switch transfer valves from bank ‘A’ to bank ‘B’ and confirm
I Preparation pressure fluctuation does not actuate any switches.
I. Trip main pump and confirm auxiliary pump starts without
A. Confirm proper oil type and reservoir level actuation of any trip valves or valve instability.
B. Confirm system flush is approved and all flushing screens are
Note: Pressure spike should be a minimum of 30% above any
removed trip settings
C. Confirm all system utilities are operational (air, water,
J. Repeat step I above but slowly reduce main pump speed (if
steam, electrical) steam turbine) and confirm proper operation
D. Any required temporary nitrogen supplies should be K. Simulate maximum control oil transient flow requirement
connected (if applicable) and confirm auxiliary pump does not start
E. All instrumentation must be calibrated and control valves L. Start auxiliary pump, with main pump operating and confirm
properly set control valve and/or relief valve stability
F. Entire system must be properly vented
Note: Some systems are designed to not lift relief valves during
two pump operation
II Test procedure
A. Oil Reservoir III Corrective action
1. Confirm proper heater operation A. Failure to meet any requirement in Section II requires
2. Check reservoir level switch and any other components corrective action and retest
(TIs, vent blowers, etc.) B. Specifically note corrective action
B. Main pump unit C. Sign-off procedure as acceptable to operate
1. Acceptable pump and driver vibration

Best
Best Practice 11.7Practice 11.7

Continuously monitor all dynamic equipment performance Lessons Learned
(pumps, compressors, steam and gas turbines) to prevent Failure to trend machinery operating points and perfor-
component failures and to optimize component MTBFs, mance indicators reduces machinery safety and reliability
unit safety and reliability. As previously stated 80% of component failure root causes lie in the
Approximately 80% of machinery component failures are related to effects of the process.
process condition changes. Failure to integrate the machinery operating point and internal per-
Failure to monitor, calculate and trend machinery performance formance to mechanical effects (vibration, temperature, etc.) impact
(efficiency, flow rate, head and power) will lead to false root cause component MTBF by not identifying the root causes of the reliability
analysis conclusions and reduced component MTBFs. issues.
Programs are available for all machinery types to download mea-
sured performance parameters (pressures, temperatures, flows and Benchmarks
power), perform required calculations and trend efficiency, flow, head This best practice has been used since 1984, while I was involved with
and power to determine: the start-up of a large petrochemical complex to identify pump
If operating condition changes are possible to optimize machinery operation outside the EROE (see B.P. 2.7) and compressor and steam
performance turbine internal fouling issues for on-line cleaning without the necessity
If machinery internal inspection is required and the predicted of shutdowns.
maintenance requirements
If machinery maintenance can be extended to the next turnaround

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