Eduardo Ballina has been with Invensys Operations Management since 1996 and currently manages the company’s water and wastewater business. Before joining Invensys, Mr. Ballina served as engineering manager at Manufacturing Technology Inc., a maker of automated equipment for the hard-disk and semiconductor industry, where he was instrumental in leading the team in charge of the electronic, electrical and software design for MTI’s automated-equipment lines of products. Prior to his five years with MTI, Mr. Ballina worked for Numeritronix, CNC de Mexico and the Materials Research Institute – Solar Energy Laboratory of the Universidad Nacional Aut—noma de México. He has more than 25 years experience in automation and instrumentation, including motion control, robotics, CNC controllers, PLCs, laser measurement and vision systems and holds a degree in mechanical-electrical engineering from the Universidad Nacional Aut—noma de México. Mr. Ballina can be reached at [email protected] or 949-639-8685.
Q: What is condition-based maintenance, and how does it differ from a typical preventive maintenance strategy?
A: Condition-based maintenance is an asset management methodology used to determine the optimum moment to perform maintenance based on the true health, usage or status of an asset. It entails performing maintenance tasks using real-time data from the operating equipment, which gives us insight into the actual operating condition of the asset. This can be based on a simple measurement or a complex calculated condition. Data also can be derived from predictive technologies, like ultrasonic analysis, or from other observations, such as a function of asset temperature, ambient temperature and RPMs.
While preventive maintenance has its place, when it is calendar-based, you run the risk of over-maintaining or under-maintaining equipment, with the corresponding effects on labor, cost and productivity. Take, for example, the case where you change the oil in your car every three months, whether you left it parked in your garage during a summer vacation or whether you used it for a trip across the country. In reality, a more effective oil change would be related to actual usage (e.g., miles driven) and driving conditions (climate, short trips/long trips, high speeds/low speeds) rather than simply based on a calendar.
Q: What are some of the key technological advances that have enabled condition-based maintenance systems to more effectively assist end-users in the timely performance of maintenance to prevent equipment failure in a cost-effective manner?
A: Standards have played a significant role, empowered by technologies such as OPC, XML, Web services, SOAP (Simple Object Access Protocol) and the emergence of object-based software platforms, such as Invensys’ Wonderware System Platform. MIMOSA (Machinery Information Management Open Systems Alliance), an interface that allows interaction with CMMS/EAM software, is a good example of an industry standard that has reduced the need to create and maintain custom interfaces in order to integrate this type of software package. Object-based software platforms have enabled more intuitive implementation of automation projects with the capability for easy reuse of engineering, standardization and configuration.
Q: One of the concerns end-users typically have with condition-based maintenance is the up-front cost of implementing such programs. For what sort of applications is the cost-benefit of condition-based maintenance advantageous? For what sort of applications is the cost-benefit probably not so advantageous at this point in time?
A: One of the key benefits of condition-based maintenance is optimizing efficiency – the right solution at the right time. This is more important in industries such as water/wastewater utilities, manufacturing and oil and gas. Each of these industries has operational needs that impact customers both upstream and downstream. Any interruption can have far-reaching effects, such as production delays that impact contractual commitments, lost revenue due to idle resources and/or governmental penalties for non-compliance with decrees or mandates.
The cost benefits of condition-based maintenance are measured individually for each organization based on their immediate levels of exposure and/or risks. Applications that might not be able to justify the initial purchase of the condition-based maintenance include those organizations whose production or volume is static and not subject to delivery or compliance demands or those industries that do not have a sufficient volume of monitored equipment, such as construction, hospitality, finance and insurance.
Typically, the higher the cost of unplanned downtime, the greater the advantage. With the use of condition-based monitoring techniques, maintenance can be planned and scheduled more effectively, which reduces downtime and enables more efficient and strategic use of materials and resources. In addition, condition-based monitoring techniques typically trigger maintenance alarms for an asset before potential damage becomes severe.
Q: In fluid handling applications, what are some of the key process variables end-users should be monitoring as part of their condition-based maintenance programs?
A: A good number of electromechanical devices, such as valves, pumps and motors, are used in these types of applications, all of which are subject to wear and tear. For pumps and motors, actual hours of operation, number of starts and stops, vibration, temperature and power usage are good examples of typical conditions to monitor.
Depending on the instrumentation and sensors that are available, key process variables to be monitored could include functions of flow, temperature, reversals, total travel, and much more. Continuous ultrasonic analysis techniques can be applied to pumps as an early detection mechanism to make the operator aware of a number of possible issues, like lubrication, alignment, or bearing problems. This can be done instead of, or as a complement to, vibration analysis.
Q: What are some of the common obstacles encountered by end-users when implementing a condition-based maintenance program? How can end-users overcome such obstacles?
A: Lack of standards is a common inconvenience. Good adoption of standards at both the CMMS/EAM and the automation sides is a good first step. A consistent naming convention for assets, for example, facilitates CBM implementation.
Another obstacle is the perception left behind by previous bad experiences based on older technologies, where costly and cumbersome custom interfaces had to be designed and maintained.
Additional barriers include internal operation vs. maintenance domains and control of the data that is largely already available to operations, but must now be made available to maintenance for use and analysis. Agreement on higher-level business strategy, related measurements and the role of each domain in achieving those measurements can improve cross-domain collaboration considerably.
Q: How do you see condition-based maintenance evolving over the next 5-10 years? How will the condition-based maintenance systems of tomorrow be better than the condition-based maintenance systems of today?
A: Ease of implementation and configuration has already arrived, but in the next 5-10 years will continue to improve. Condition-based monitoring will be commonplace and an integral part of asset management implementations.
Connectivity also will continue to improve with further standardization/integration of EDDL, FDT/DTM and FDI for instrumentation; wider acceptance/deployment of OPC-UA; and faster, more secure communications infrastructures.
Other improvements will be "offline" analysis coming online and advanced diagnostics embedded in the asset. This also will increase the number of assets with some form of instrumentation, like motors with embedded self-learning voltage and current analysis capabilities. So as more and more data from assets can be monitored in an automated fashion, additional algorithms and improved visualization techniques will be required to effectively manage the information and continue to optimize maintenance spending, asset availability and utilization.
