Hydac has developed a new condition monitoring system to ensure accurate monitoring of process values on drillships.
Hydac’s new VisiWinNET-based CM-Expert condition monitoring system is designed for needs-oriented, planned maintenance providing machine availability coupled with cost minimisation.
One of the leading corporations in the field of fluid technology and hydraulics, Hydac offers a comprehensive product portfolio of hydraulic components, which are used in the automotive industry, machine tools, aviation, steelworks, navigation and construction machinery.
Of crucial importance for the faultless function of the hydraulics is the quality of the hydraulic oil. Hydac's sensors capture the essential measured variables of the machines or plant hydraulics in operation, with the central data recording and evaluation done through the CM-Expert condition monitoring tool. This keeps the plant operator informed about the exact condition of the hydraulics at any time, guarantees a reliable operation, and allows needs-oriented and planned maintenance.
For the redevelopment of the condition monitoring tool Hydac required an appropriate development tool. Among the search criteria were current technology, integration into the .NET framework, free expandability for special functions, and simple interaction with Visual Studio.
The concrete example of a drillship particularly exemplifies the use of the condition monitoring system. Through a special compensation system coupled with dynamic positioning the Stena Drilling drillship can provide its full drilling capacity of up to 3,000m depth in seas of up to 7.60m. The monitored hydraulic plant feeds five huge hydraulic cylinders that control the lifting and lowering of the drill stem. In addition these cylinders define the pressure put on the drill head. Loads of up to 1,000 tons can be lifted and lowered through these cylinders. The hydraulic plant has an oil volume of 90,000 litres with a maximum flow rate of 24,000 litres per minute. The offshore operation with its extreme environmental conditions is particularly demanding on the hydraulics and makes the supply of spare parts expensive. A hydraulics breakdown leading to an operational standstill would be very expensive. Therefore, the crucial parameters of the hydraulic plant are permanently monitored by the condition monitoring tool.
Through a self-contained system that is independent from the hydraulics control, different criteria are gathered by sensors. The measured variables from 80+ sensors are passed through a control to the condition monitoring system where they are recorded and monitored. The permanent monitoring and documentation of the hydraulics data automatically informs the user about maintenance-relevant state variables, and issues an alert should safety-relevant values be exceeded or under-run. This prevents cost-intensive breakdowns and consequential losses, while improving machine availability. Maintenance and servicing activities can be optimised, and components are used to the full potential of their operating life.
Software for the condition monitoring
The flexible and modular design of the CM-Expert software allows its use beyond these hydraulics applications. Monitoring of clean rooms with air particle measurement is enabled by the flexibility of both the software and the control. The open and manufacturer-independent system allows the connection with different sensor types. Even other manufacturers' sensors can be connected and interpreted to further expand the possibilities of the application. Due to its self-contained design, the system can be added to any existing plant without problems.
In the condition monitoring system, the measured variables are recorded and filed. For every variable measured, monitoring limits can be defined, and a message or alarm triggered if they are exceeded or under-run. These monitoring limits can, with the appropriate user rights at any time be amended through a context menu with the appropriate sensor control. In addition, a graphic line chart display of the sensor value can be accessed providing the user with a direct view of the change of the measured variable over the time.
The software is optimised so that the user can freely define the values to be displayed on a so-called favourite’s page. This goes as far as any number of values being displayed in different charts, and the display parameters being freely set, allowing the user to display the most important process parameters centrally on one screen. An export function allows selection and storage of the recorded data, e.g. for further external evaluation in Excel.
Process visualisation as the basis
The INOSOFT VisiWinNET process visualisation system is the basis for the CM-Expert condition monitoring system. VisiWinNET Professional is the appropriate development tool for Hydac, containing the required functions, and in addition providing the possibility to simply integrate own functions. This has enabled Hydac specialists to build on the broad functional range of the process visualisation system.
A further standard function is the alarm and messaging system for displaying and recording the alarms. The upcoming alarms and messages are displayed to the user clearly. In addition to acknowledging the alarms the user can also lodge a note on the alarm. The evaluation of the historic alarms and notes allows the plant operator to draw conclusions for process optimisation. Recording and filing of the data is done in the VisiWinNET archive system, providing a simple facility for a graphic display of the recorded data. This way, the value pattern of every recorded sensor can be displayed as a trend chart. As an internationally active corporation with worldwide usage of the software adapting the language to the appropriate national language of the customer through the integrated online localisation is an important function for Hydac.
CM-Expert also offers configuration and setting facilities to the end user. These are linked to appropriate user rights so that only authorised persons can adapt the limit values for the monitoring. The VisiWinNET user administration allows simple user configuration, and provides prepared templates that were adapted by Hydac for their application.
The integration of VisiWinNET Professional into Visual Studio allowed Hydac the realisation of special requirements for their condition monitoring software with self-created controls. An example is the analogue sensor control, one of the main operating elements for the user. It connects the most important data of a sensor centrally in a control. To provide the user with a quick overview the monitoring limits are shown directly in the control. As a central operating element the sensor control not only shows the measured value but also allows the access of further functions through a context menu. This way, the user with the appropriate user rights can for example, directly enter a dialogue to change the limit values or access a graphic display of the measured value progress through a trend chart. A smooth transition between online and historic data makes it easy for the user to display past data. This can be controlled by entering a certain time span or intuitively through a scroll bar.
Robertus Koppies, Head of the Condition Monitoring department with Hydac concludes that the CM-Expert system provides many standard functions, and allows them the free adaption to their field of application.