When optimally selected and applied, the latest generation of smart sensors can have a positive impact on predictive maintenance strategies for fluid power applications.
Real-time data collection via smart sensors can influence decisions about when to schedule downtime to carry out maintenance operations, helping to maximise productivity.Why adopt predictive maintenance?
Maintenance operations are traditionally based on being either reactive or preventative. A reactive strategy means a loss in production and incurring unforeseen costs, while a preventative strategy often sees systems or parts repaired simply because they are listed on the general maintenance procedures, rather than when they actually need it.
Attention has been gradually shifting to predictive maintenance, spurred on by the emergence of Industry 4.0 and sophisticated ‘smarter’ technologies. For fluid power systems, this means a whole new level of condition monitoring, to the extent that maintenance personnel can determine whether something out of the ordinary has occurred.
Ultimately, every process has a ‘heartbeat’, so the question to ask is has that heartbeat changed over a certain period of time? Maybe it has become slower or faster, for instance. This is where smart sensor technologies begin to pay dividends.
Get smart with maintenance
The latest sensor technology available for fluid power systems, such as the P8S CPS series from Parker, have evolved to offer high quantities of data which offer the opportunity for plant managers to transform how they operate and maintain industrial equipment.
Embedded smart sensors can today be integrated with numerous different low-level fluid power products, from connectors, hoses and tubing, to pumps, motors, actuators and filters – all as part of an Industry 4.0 installation. One of the principal opportunities arising from this concept relates to predictive maintenance. For example, some of the diagnostic data generated from control valves could be invaluable in troubleshooting power issues.
Among the common concerns in fluid power systems is voltage sags that can occur downstream on long runs, which sometimes lead to misfiring valves. Normally, without an oscilloscope, there are no means of diagnosing the root cause of the problem. In contrast, if each valve manifold node included voltage sensing, a ‘sweeper’ program could be written to record voltage levels across the machine during certain periods of the cycle.
Unified communications standards
Of course, selecting an Industry 4.0-enabled sensor is one thing, but ensuring that it can communicate with other such devices is quite another. For this reason, it is imperative to select a sensor vendor that operates a centralised strategy to ensure that its smart devices and sub-systems share open communications standards and best practices. IO‑Link is the first I/O technology for communicating with sensors and actuators to be adopted as an international standard (IEC 61131-9). This open protocol is bringing the world of Industry 4.0 to component level and already proving essential in ensuring interoperability across multiple technologies and manufacturers.
Consider a pneumatic device, for example, which is being used to grip workpiece blanks and load them into position on a machine tool. Here, the voltage of the coils across the solenoid valves can be monitored for signs of impending failure. In such a scenario, IO-Link can offer budget-friendly communication with low-level devices, connecting them to motion controllers that subsequently connect to a factory network and, if required, to the cloud.
Smart sensors and other Industry 4.0-enabled devices must work in co-operation with products from other manufacturers. In fact, the value of any connected digital solution is directly proportional to its interoperability. There is no place for proprietary solutions; an open, exchange-based architecture that enables interoperability with third-party products, applications and platforms is essential.
The security issue
Talk about Industry 4.0 and one recurring area of concern arises - security. Indeed, this issue has been central in discouraging many plants from taking the decision to connect machines and devices to the cloud and gaining the insight required to predict failures and optimise performance at the component level.
For any company concerned about this issue and seeking guidance on how to move forward, this is the point where choosing the right vendor is of the essence.
It is critical to choose suppliers who can share technical knowledge and hands-on experience gained from working across a wide range of advanced applications.
With a specific focus on fluid power installations, the selected vendor should be able to offer advice on where sensors need to be integrated to obtain optimal insight, the type of data to collect, and how to present the results to MRO (maintenance, repair and operations) personnel in the way that is most useful. Progressive, forward-thinking vendors are striving to bake in best-practice data encryption in motion and storage to create secure end-to-end Industry 4.0-enabled systems.
The big picture
Using the latest sensor intelligence is now about far more than simply monitoring factors such as position and speed. It’s about using data, collected in real time, to provide vital information concerning service life that can help facilitate the implementation of predictive maintenance. This data can be used to identify when a machine or system is not functioning correctly, or at its optimum efficiency. Early sensor notification of issues allows system operators to investigate, consider, plan and schedule the required corrective maintenance for a time when production throughput is either low or can be stopped. This could be overnight, during a larger planned plant maintenance shutdown, or whenever there is the least impact on those all-important customer delivery schedules.
Continuous position sensing devices can make a significant contribution to creating a smarter, more efficient factory environment. To find out more, download our CPS Smart Sensing Brochure that covers continuous position sensing using analogue signal or IO-Link communication for linear actuators, and discover how you can better schedule corrective maintenance and reduce your downtime.
Article contributed by Franck Roussillon, product manager, actuators, Pneumatic Division Europe, Parker Hannifin Corporation.