Vibration Condition Monitoring

Vibration Condition Monitoring (VCM)

Vibration Condition Monitoring (VCM) is a kind of machinery PdM technique which can help to determine the condition of in-service equipment in order to predict when maintenance actions should be performed.By measuring the vibration and identify the vibration signature of rotating machines, ones can determine their mechanical condition without disturbing the whole plant operation.This maintenance strategy is cost-effective and can provide important information and solution to the plant operators about the maintenance budget and planning.

Recommended machines to be monitored:

Motors
Chillers
Compressors
Pumps (seawater, chilled, condensed & heat water)
Fans (TVF, AHU)
Cooling towers
Gearbox
In generally, VCM for rotating machines above 30kW is recommended

Machine Fault Diagnosis

Common machinery faults can be identified by VCM:

Coupling misalignment
Mass imbalance
Roller element bearing fault
Sleeve bearing problem
Mechanical looseness
Electrical line problem

Gear problem
Impeller problem
Belt and pulley problem
Structural issues
Flow problem

Benefits

Extend machine life
Prevent unexpected machine failure / emergency shutdowns
Prevent catastrophic damage / accidents, safety issues
Diagnose machine faults at early stage and predict time to failure
Reduce unnecessary over-haul and maintenance costs
Optimize spare parts handling
Better maintenance plan can reduce machine outage downtime
Determine and solve the root cause to avoid recurring failures
Reduce insurance policy cost of the assets
Energy efficiency
Reduce vibration-induced noise & nuisance for better indoor environment quality
Interruption of plant operation is nearly negligible

Approaches

Stage 1) Test and Commissioning / Vibration Acceptance Test for new machines or after over-haul / maintenance works, to ensure the quality of works.

Stage 2) Routine Site Vibration Survey – regular site vibration measurements in 6 to 12-month basis (survey interval subjected to the size and how critical of the machines / plants) to trend the vibration levels and early-stage fault development of the machines.
Warn the operators if the levels / conditions change suddenly or exceed the alarm levels. Machine fault(s) can be addressed and necessary maintenance actions will be recommended.

Stage 3) Real-Time Online Vibration Monitoring – Real-time and 24/7 continuous vibration monitoring for critical or remote machines to ensure the ultimate reliability grade. With the integration of PdM strategy and the concept of Industrial Internet of Things (IIoT), vibration data of the machines will be collected and analyzed by the online monitoring system. Early-stage fault diagnostic algorithm and alarm triggering program will then be setup by our vibration analysts based on the baseline data collection / international / manufacturers’ standards.

Stage 4) Advanced Vibration Investigation & Diagnosis – further vibration test and analytical skills involved to identify the exact fault and root cause, such as cross-channel phase measurement, time-synchronized averaging, coast-down / run-up test (bode plot), modal analysis, rotor balancing etc.