Reliability Management
Predictive Maintenance & Conditional Base Monitoring (CBM)
PREDICTIVE MAINTENANCE – NON DESTRUCTIVE TEST
Predictive maintenance (PdM) techniques help determine the condition of in-service equipment in order to predict when maintenance should be performed. This approach offers cost savings over routine or time-based preventive maintenance, because tasks are performed only when warranted.
PdM, or condition-based maintenance, attempts to evaluate the condition of equipment by performing periodic or continuous (online) equipment condition monitoring. The ultimate goal of PdM is to perform maintenance at a scheduled point in time when the maintenance activity is most cost-effective and before the equipment loses optimum performance. This is in contrast to time- and/or operation count-based maintenance, where a piece of equipment gets maintained whether it needs it or not. Time-based maintenance is labor intensive, ineffective in identifying problems that develop between scheduled inspections, and is not cost-effective.
The "predictive" component of predictive maintenance stems from the goal of predicting the future trend of the equipment's condition. This approach uses principles of statistical process control to determine at what point in the future maintenance activities will be appropriate.
Most PdM inspections are performed while equipment is in service, thereby minimizing disruption of normal system operations. Adoption of PdM can result in substantial cost savings and higher system reliability.
To evaluate equipment condition, predictive maintenance utilizes non-destructive testing technologies such as infrared, acoustic (partial discharge and airborne ultrasonic), corona detection, vibration analysis, sound level measurements, oil analysis, and other specific online tests.
Infrared monitoring and analysis has the widest range of application (from high- to low-speed equipment), and it can be effective for spotting both mechanical and electrical failures. Infrared detects equipment radiation in the form of temperature changes; some consider it currently be the most cost-effective technology.
Vibration analysis is most productive on high-speed rotating equipment and can be the most expensive component of a PdM program to get up and running. Vibration analysis, when properly done, allows the user to evaluate the condition of equipment and avoid unnecessary equipment failures / breakdown.
Acoustical analysis can be done on a sonic or ultrasonic level. New ultrasonic techniques for condition monitoring make it possible to “hear” friction and stress in rotating machinery, which can predict deterioration earlier than conventional techniques. Ultrasonic technology is sensitive to high-frequency sounds that are inaudible to the human ear and distinguishes them from lower-frequency sounds and mechanical vibration. Machine friction and stress waves produce distinctive sounds in the upper ultrasonic range. Changes in these friction and stress waves can suggest deteriorating conditions much earlier than technologies such as vibration or oil analysis. With proper ultrasonic measurement and analysis, it’s possible to differentiate normal wear from abnormal wear, physical damage, imbalance conditions, and lubrication problems based on a direct relationship between asset and operating conditions.
Sonic monitoring equipment is less expensive, but it also has fewer uses than ultrasonic technologies. Sonic technology is useful only on mechanical equipment, while ultrasonic equipment can detect electrical problems and is more flexible and reliable in detecting mechanical problem.
Oil analysis is a long-term program that, where relevant, can eventually be more predictive than any of the other technologies. It can take years for a plant's oil program to reach this level of sophistication and effectiveness. Analytical techniques performed on oil samples can be classified in two categories: used oil analysis and wear particle analysis. Used oil analysis determines the condition of the lubricant itself, determines the quality of the lubricant, and checks its suitability for continued use. Wear particle analysis determines the mechanical condition of machine components that are lubricated. Through wear particle analysis, you can identify the composition of the solid material present and evaluate particle type, size, concentration, distribution, and morphology.
In view of today’s fast growing and high competitive business & social trend, a stable and reliable facility / utility system is essential. Vital industries such as telecommunication (eg: mobile phone system, wireless system, internet,), transportation (eg: airport, railway station, harbor, GPS), finance (eg: GIRO, credit card, MEPS), building (eg: hospital, civil defense, power generation, water treatment) etc, required uninterrupted utility supply to ensure smooth and speedy operation for maximum efficiency and effectiveness.
Thus, a proper PdM program is crucial to warrant / minimize unwanted interruption or facility failure which may lead to severe payoff or even life loss. The PdM program should include the following:
a) Online Infrared Thermal Radiation Mapping
b) Computer-Aided Acoustic Partial Discharge Analyzing
c) Capacitive Approach EMF Transient Partial Discharge Analyzing
d) Power Measurement And Analysis
e) Vibration Data Analysis
f) Online & Offline Motor Evaluation
g) High Frequency Motor Survey
h) Leak detection
ZERO COST ENERGY SAVING & ZERO INDUSTRIAL DOWNTIME
AREA OF APPLICATION
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