Using HART to drive predictive maintenance allows Shell to increase the availability of its instrumentation resources.
Because of the interoperability, interchangeability and backward-compatibility designed into both wired and WirelessHART, you don't have to ever do a rip-and-replace. You can upgrade individual devices and know that they will operate in your system perfectly from the start.
With other device protocols, there may be revisions, interoperability issues and other problems that might cause you to rip out what you have and put in something different. That's a hard sell to a cost-conscious management. It's an embarrassment that can be completely avoided when you standardize on HART.
HART is easy to sell to operators and instrumentation engineers alike, because it is simple, yet powerful. Because of the preponderance of HART devices in the field, nearly every engineer and operator already is trained to work with HART commands. Whether it is wired HART or WirelessHART, buy-in is much easier to achieve when the devices are not running a new and different protocol. There is no learning curve with HART. And when there is an upgrade, the operators already know how to use the network—because it still is HART.
Sometimes, engineers are swayed by other than technical arguments. The drive toward new technology for its own sake often costs more and produces less than a simple concentration on what the plant's goals are and what is needed to produce those results. Shell Canada found that HART fitted its needs better than other fieldbus communication protocols because it was simpler, more reliable and just as secure, if not more. HART, Bahniuk feels, is more straightforward, and he was pleased to note that he can get the same information, including diagnostics and additional PVs, from HART as from any other type of fieldbus.
One project Bahniuk detailed in his application to become HART Plant of the Year was installing a valve position feedback system. Shell felt it had to install some sort of valve feedback system until it realized that HART data could give them valve position on 700 to 800 valves.
MOL already had a significant number of HART-enabled devices when it began its maintenance integration in 2005. By leveraging the use of the entire capability of HART communication, it was able to integrate its maintenance management system with the control system and the enterprise data system easily and without ripping and replacing what was already in place.
One very large benefit of HART communication is that by design it is backward-compatible. Now that MOL, as Gábor Bereznai, head of instrumentation related in the August 2012 issue of Control, is beginning to use wireless instrumentation, it has found that not only can the engineers extend their sensor reach using WirelessHART, but they can also use WirelessHART adapters, such as the Emerson "THUM," to more fully integrate their existing wired devices into the common network.
As MOL discovered, HART makes it easy to integrate the entire field device network into both the control system and the maintenance system. This makes it easy to deliver the real-time data plant operations needs to fine tune the plant to produce the most revenue at the highest level of productivity.
Shell's Bahniuk related the benefit of HART to loop testing and commissioning—the very first steps to integration of the network. Shell had ordered all the devices pre-configured to avoid having to do it onsite, but only about 50% of the devices were actually configured at the factory. Shell was left to do the others onsite after all.
This, of course, could have produced a huge delay in commissioning the plant. Using the full power of HART, however, Shell created a device database which made device configuration fast and easy, and the engineers were able to show management that the system was 100% accurate. They met their very tight project time and saved a large amount of time and money.
All leading process industry facilities develop risk mitigation plans. Both for operational and maintenance risk reduction, and as an integral part of any security risk reduction plan, HART can serve as one of the key pillars of the plan.
Using the power of HART can produce production alarms as well as maintenance alerts automatically, that can lead to increased functional safety. The fact that neither wired HART nor WirelessHART use TCP/IP means that the field device network is inherently safe from the typical hacker. The WirelessHART security scheme for joining the system and making sure that data transmission is not compromised means additional safety as well. Properly used, HART communications can be a first line of defense against device- and controller-centered attacks, as well as errors inside the plant.
Once you have clearly defined your needs and produced a needs-based plan, you can use the power of HART to help you operate your solution. You have leveraged your existing field device legacy to its fullest extent, avoided any rip-and-replace for sensors or analyzers or final control elements and other devices, and improved the ability of your field device network to handle additions and changes. This built-in agility gives you the confidence to tell management that you are ready for 21st-century operations.
MOL believes that because of its HART-based implementation, it is a world leader in the use of diagnostic information and integration into the asset management system, and thence to the SAP CMMS system via bidirectional communications. It is able to determine the health of the field device system, both individually and as a system and reduce the number of breakdown events and the amount of downtime.
What does this mean? MOL believes that the use of HART technology as the central pivot of both operations and maintenance may yield as much as €700,000 per year in "lost revenue" due to better loop tuning and predictive maintenance.
Leaders in the process industries such as MOL, Shell Canada and Bruce Power leverage fully the power of HART and WirelessHART.