Most installed measurement instrumentation provided by the 4-20mA signal is "smart," according to industry estimates. But in order to maximize your investment in smart measurement devices, better manage your operations and lower your operating costs, intelligent information in those devices should be available to operators and managers. Because without a better view of the diagnostic condition and status of your devices, management has limited ability to take action that can have significant, positive impact on your bottom line.
Intelligent Device Information
Measuring devices, regardless of field protocol, can communicate many categories of information. In addition to multiple measurements (with newer devices reporting as many as eight process variables), devices can report important device diagnostics and process information. Think of the usefulness of the diagnostics in your automobile or your computer: The diagnostic system in your automobile performs hundreds of measurements and adjustments continuously to provide a quick indication of the status and potential availability (or lack thereof) of your car or your computer. Using FDT Technology, you can get the same type of diagnostic warnings or device status from your installed smart instrumentation.
Pending diagnostic warnings, however, are only helpful if a warning is investigated, and appropriate action is taken. Your smart measurement device has the ability to provide valuable diagnostics information — but it's valuable only if you're checking to see if there is a problem. An FDT-based Frame Application using DTMs (Device Tool Managers) is a cost-effective tool needed to review and analyze these potential problems and can help you avoid unplanned situations.
Move from Reactive to Proactive
With many updated control and asset management systems, intelligent device diagnostic information is accessible and available for immediate use. For those that don't, there are many different cost-effective products that make access to intelligent device information possible. This diagnostic information enables you to change your maintenance activities from reactive — work on what's broken — to more proactive or even predictive activities, such as fixing small problems before they turn into bigger problems.
Imagine the benefits of using real-time device diagnostics to reduce the number of trips to the field, prevent an unscheduled shutdown or reduce the length of a scheduled shutdown. Whether you are part of the reliability, maintenance, process improvement, management or other plant function, putting this valuable information to work can produce big results with relatively small investments and low risk.
Let's look at a some examples of the real bottom-line benefits that are being realized by users around the world…
Real Bottom-line Benefits
In 2002, the MOL Group's Danube Refinery in Százhalombatta, Hungary, set out to improve profitability using its installed smart technology in 2002, and only three years later, decided to overhaul its maintenance systems with a new, unified asset management system (AMS) strategy. The combination of the two technologies has changed the way MOL runs maintenance and the way it looks at diagnostic data.
The company connected many of the plant's smart devices, such as control valves and instruments used in critical control loops, directly into the plant's AMS. This has resulted in an on-line diagnostic system in which instrument signals are directly connected to plant maintenance and control systems.
"On-line diagnostics provided by the these instruments does something more than preventive maintenance," says József Bartók, automation engineer at MOL Danube Refinery, adding that this "ensures the stable operation of the system and increases the precision of control." Beyond fixing what breaks or keeping the plant running, a reliable, stable operation contributes to bottom-line profitability.
For example, when the head pressure control was slow on one unit, it led to the assumption that a valve was stuck and in need of removal and repair. But technicians using on-line diagnostic tools used device diagnostic data to interrogate the valve and find current-to-pneumatic damage in the intelligent positioner — but not the whole valve. Operators put the valve in manual, and the fix took a half hour of instrumentation work. This repair saved the plant at least two days of unscheduled downtime, worth at least $834,400.
Before using device diagnostics, about 60 percent of the control valves were selected for repair in a typical plant shutdown. While all faulty valves were likely corrected, others may have been removed unnecessarily due to a lack of data. With device data, the company estimates average savings of $70,000 per unit, per shutdown; it's no longer necessary to disassemble and repair failure-free control valves during a shutdown.
Having a better handle on valve performance also allows MOL to pull fewer valves at turnaround time, substantially reducing maintenance costs and shortening the time needed before production is resumed. "Ten years ago, we pulled all of the valves," Bereznai says. "Now, we pull two dozen instead of 200, saving $20,000 to $70,000 per turnaround."
Similarly, at the Dow Chemical Company's complex in Deer Park, Texas, intelligent device diagnostics have helped slash plant trips attributable to instruments and control valves by 70% over the past three years, delivering "millions of dollars in savings," according to Dow's Shadrach Stephens, instrument reliability engineer, and Christopher Garcia, instrument/electrical technology leader.
In order to prioritize their efforts, Stephens and Garcia first analyzed sources of downtime and found that five reactors accounted for a full 48% of instrument- and valve-related outages. "We needed to see what the opportunity was so we could justify the necessary resources to management. Where could we make the biggest bang for the buck?" Stephens says.
Their first priority was to deploy continuous monitoring for the plant's most critical control valves, which also were the biggest contributors to downtime. The plant now uses asset management software not only to help mitigate failures, but also to push out preventive maintenance intervals, Stephens says. "We can work with operations to resolve issues without incurring downtime."
"And as we get into more root-cause investigations, it definitely helps to have more data," Stephens continues. "Intelligent device information helps us understand what's happening and to mitigate potential problems." Up next for Dow Deer Park is dynamic analysis of flow measurement data to identify and rectify issues such as fouling and plugging. "That's the next tier for us," Stephens says.
Conclusion
The intelligence in your installed measurement devices might be one of the under-utilized assets available in your plant today. By integrating the intelligent device diagnostics into an asset management or automation system, you begin the process of monitoring the device status, allowing the opportunity to improve your bottom line. Using FDT Technology-enabled solutions, which includes a Frame Application and device DTMs that are available from your device suppliers, you will be able to identify minor problems before they become critical, lowering maintenance and operating costs. FDT Technology-based products and solutions are supported by and available from most major device and systems suppliers.
So take the first step to realizing bottom-line benefits of intelligent device information integration. For more information, check out the presentation video on Proactive Maintenance Strategies with Bottom-Line Business Benefits on YouTube. Please also visit www.fdtgroup.org.
