Vibration monitoring 101: A complete guide
Introduction
Vibration monitoring of critical machinery forms a fundamental element of most successful condition-based maintenance (CBM) strategies. Vibration data can provide key insights into the health of machinery and the possible issues that could lead to failure. This means vibration monitoring is a vital tool to identify potential issues early, provide insight to the crew on corrective actions and ensure machinery and the ship remains operational.
Vibration monitoring is a versatile tool for monitoring the condition of rotating and reciprocating plant machinery. Methods vary from the basic to the sophisticated and employ several techniques and instrumentations.
This guide explores the following elements of vibration monitoring:
- Technologies available and where they fit best
- Issues that can be identified through vibration monitoring
- Example of vibration monitoring in practice to avoid failure
- How to implement vibration monitoring on your ship in five easy steps
Vibration monitoring technologies
Collection
The first step in effective vibration monitoring is the accurate collection of vibration data from the identified machinery. Technology is a key enabler to successfully achieve this.
Vibration sensors
The next step irrespective of collection method, is the application of sensors to the machinery.
The diagram outlines where on the machinery sensors can be placed. This will differ slightly depending on the type of sensor and machinery type. Condition monitoring (CM) consultants assist in identifying where on the machinery the sensors should be placed and installed.
Data collection technology
Handheld
Handheld vibration data collection is simple and quick to setup and begin to monitor the vibration of your machinery. It involves the manual collection of data through a handheld collection device.
Device: Mimic Bluetooth accelerometer + Android rugged tablet
Collection takes place on a periodic basis with CM jobs managed within the planned maintenance system (PMS). Mimic offers integration options into a variety of PMS systems including: Bassnet, SIS, Shipnet, TM Master and ABS NS.
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Automated wireless
The next vibration collection technology option is wireless data collection. This approach requires the application of wireless Bluetooth sensors to the machinery, connected to wireless gateways connected to the ship’s network through either Wi-Fi or Ethernet. Below is an example architecture of this.
The ruggesdised devices are designed for the harshest marine environments and have a multiyear battery life.
The wireless approach is the most cost effective way to achieve fully automated data collection, as data is collected without the need for human intervention. The collection of data is triggered from machinery start/stop signals imported in the Mimic CM system from the vessels Integrated Monitoring, Alarm and Control system (IMACS). This ensures data is only connected when the machinery is operational.
The wireless approach is ideal for machinery that is more difficult to access, however the Bluetooth signal should still be able to reach the network gateway. This automated data collection approach is suitable for more critical machinery to ensure data accuracy and more regular readings (usually hourly/daily).
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Automated wired
The final data collection option is the fully wired data collection approach.
This requires the running of cable from the machinery sensors through to centralised data acquisition panels. These panels then connect directly to the data analysis program (Mimic).
The fully wired option provides real time data feedback and is not limited by the need for wireless connectivity. This makes it a good option for highly critical machinery that have rapid failure modes, such as turbochargers. ATEX rated hardware is also available meaning it is ideal for monitoring equipment where intrinsically safe hardware is required. This has become increasingly important given the rise in LNG-powered ships.
As with the wireless monitoring system, an integration is required into the vessel IMACS system to acquire a running signal, to ensure data is only connected when the machinery is running.
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Deciding on the right data collection technology
Now we have covered the three main vibration data collection approaches and technologies, it is time to review how to decide which is most suited to your operation. Given the variety of options, it certainly is not one-size fits all, even on a single installation. Hybrid models are extremely successful in ensuring each asset is monitored using the technology that suits it best.
Combinations of handheld + wireless or handheld + wired are commonplace. The criteria for making these decisions are based on three core areas:
- Asset criticality - Low vs highly critical
- Asset location - easy to access for manual readings/inaccessible
- Failure mode/Asset type - speed of failure
Mimic CM consultants are best place to advise on the most suitable collection method based on assets covered within a CBM strategy.
Analysis action software
Once the data is collected and combined, data analytics software is required to make sense of the data collected and provide actions.
Mimic is uniquely placed to apply advanced analytics to vibration data to:
- Trend vibration data over time
- Identify faults with machinery
- Provide specifics on the nature of the fault – e.g. looseness, unbalance etc.
- Analyse asset types side-by-side
- Predict future failures
- View performance and oil analysis data to enhance the analysis process
- Time wave form and spectral analysis displays can be called up with the ability to overlay and compare with other historical data
Issues identified through vibration monitoring
Vibration monitoring not only identifies that there is a potential issue with an asset but more specifically, what that issue could be. A list of some of the issues that can be identified are listed below:
Example of vibration monitoring in practice to avoid failure
Read the full case study: Mimic supports cruise ship’s maiden voyage
How to implement vibration monitoring on your ship in five easy steps
Vibration monitoring is not a complex and costly change project. It can be simple and quick to implement to ensure quick time to value.
Step 1 - Identify installations
Identify suitable ships and align crew on approach.
Step 2 - Asset identification
Identify assets that would benefit most from vibration monitoring based on criticality, high failure rate and asset location.
For further guidance, check out this blog.
Step 3 - Agree hardware approach
Based on asset type, agree the best hardware approach, i.e. manual vs automated.
Step 4 - Plan and deliver
Plan delivery approach and deliver.
Step 5 - Run and review
Embed system and plan in review stages to ensure optimal output and usage.
Engage a Mimic vibration monitoring specialist today
Having explored the value of vibration monitoring as part of your maintenance approach, get in touch with JF Mimic’s specialists to discuss your requirements.