Condition Based Monitoring
Condition Based Monitoring is a maintenance strategy that allows to monitor the actual condition of an asset, extracting information to understand the machines' actual wear, degradation and if a relevant change has occurred.
CMB is often employed in monitoring discreet components of an industrial system such
as motor, fan, pump, mixer, compressor, conveyer, shaft, bearings, etc. The
method consists of the following:
· Determine Key-Parameters (KP): Monitor parameter, such as vibration, temperature, pressure, humidity, etc. at multiple points.
· Determine Key-Indicators (KI): Use statistical and analytical methods to analyse and get indicators which can indicate the present condition of the component. For example, using frequency analysis, harmonics, and peaks in vibration data, we could indicate the motor state to be either normal, warning, or critical state.
· Data analytics platform: Store this data over the lifetime of the component, which could range from few months to a year or more. Analyse this data and baseline the thresholds. This will assists in generating alerts (visual alerts on factory floor, sound alarms, SMS, Emails, etc) whenever the Key-Indicators (KI) thresholds are crossed.
The quality and sensitivity of sensors used for measurement is critical for CBM systems. Piezoelectric or MEMS based vibration sensors, accelerometers, gyroscopes, temperature sensors are typically employed to measure key-parameters. Some of these, such as the ones from ‘Analog Devices ®’ offer fully integrated low-power devices which can perform multiple tasks like below periodically
Periodically wake up à capture vibration data à Perform Spectral analysis and binning à Apply user-configured spectral thresholds à Wirelessly Report Pass/Fail & Status data à Sleep and conserve energy.
ConnectedThinks IoT & analytics platform enables CMB in an
efficient and user-friendly way through enterprise level data storage,
analytics, automated determining of key-indicators and providing configurable
alerts to multiple end-points.
CMB Pros & Cons
- Cost Sensitive
- Ease of deployment for on-prem & offline setups such as remote installations
- Useful for quickly detecting wear-out of components like bearings, gears, chains, belts, brushes, shafts, coils, and valves
- Easier for the product or equipment manufacturer to bundle as part of offering
- Calibration process is manual, error prone and difficult to test. Differing deployment conditions and load conditions demand separate calibration
- High sensitivity sensors needed
- Stringent thresholds result in false or too many alerts and results in critical alerts being missed
- Lenient thresholds result in some damage occurring before issue is detected
- No easy way to determine Remaining Useful Life (RUL). Difficult to integrate data from multiple sensors and equipment logs