"And as we get into more root cause investigations, it definitely helps to have more data," Stephens continues. " HART helps us mitigate problems by creating a culture of making data-based decisions." 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.
At the MOL Group's Danube Refinery in Százhalombatta, Hungary, diagnostics also are the primary focus of the plant's efforts to stay ahead of valve problems, according to Gábor Bereznai, head of the petroleum refinery's automation and electrical department. "Our PSA [pressure swing absorption] unit is full of control valves and on/off valves, and any valve failure will shut down diesel production at a cost of $300,000 a day," Bereznai explains. With HART- and Foundation fieldbus-based diagnostics "we've avoided many unplanned shutdowns," Bereznai says, "and diagnostics give us more confidence to run longer as well."
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."
Dow and MOL aren't alone in their renewed awareness of asset management's potential or in their push for improved equipment reliability. "Today I hear from many global companies that are investigating methodologies to ensure that devices are working properly," says Frank Fengler, head of device integration for ABB.
Integrated HART from the Start
While multiplexers often are used to extract HART data from 4-20mA signals, shunting it off to a standalone plant asset management system, many newer analog I/O modules and associated control systems offer integrated HART connectivity built-in from the start.
At Rockwell Automation, for example, no fewer than six different I/O platforms include integrated HART capabilities. "Scalability is important," notes Yuri Zelenkov, product manager for process networks. "If you don't have a full-blown plant asset management system, you can still have that diagnostic information at your fingertips in the control system. Then, once you're up and running, you can begin to programmatically implement basic asset management strategies to go after the low hanging fruit."
Similarly, Honeywell Process Solutions supports integral HART communication in several generations of I/O, including its latest Series C I/O platform offerings. "For an end user migrating to a new system, it really is a plug-and play situation," notes Joe Serafin, product manager, open protocols, for Honeywell. "There aren't any big struggles any more. You're opening the floodgates of information."
And because HART diagnostics are so readily available within modern control system architecture, some 50% of modernization projects also include a companion plant asset management system, estimates John Yingst, product manager for Honeywell's Field Device Manager plant asset management software.
And with WirelessHART of course, all that richness of diagnostic information automatically comes along for the ride, and can be readily integrated into control and asset management strategies, notes Bob Karschnia, vice president, wireless, Emerson Process Management. "It's all about providing more information to keep the plant up and running, maximizing productivity and ensuring safety and environmental protection," Karschnia says. "HART Communication will continue to evolve for decades to come."