Traditional manual methods of tracking control valves and other assets are expensive and error-prone. RFID tracking can save process companies hundreds of thousand dollars per year
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Shannon Jelken, a Senior Research and Design Engineer at Emerson Automation Solutions, writes that much of the information regarding the status of components installed in the field is housed in paper files, posing problems for technicians and engineers.
In his article, The Case for RFID in Process Plants, in the Spring 2019 issue of Valve Magazine (page 24), he says a more modern scenario is where a technician points an RFID reader at a valve (Figure 1), obtains the valve’s serial number and can later access all the data needed from a handheld mobile tablet or smartphone.
Figure 1: Using an RFID reader, a technician can identify plant assets, like a control valve, equipped with an RFID asset tag.
The Paper Trail
Jelken says that, today, most maintenance departments deal exclusively with paper records regarding valve maintenance, parts lists, service, repairs and other data regarding each valve’s history.
Some of these papers reside at the site in the maintenance shop and others are at a central office. Some operators rely on component vendors to keep records. Significant effort is required to manually maintain files, and they often are not properly kept up to date. There is a high cost associated with the time involved in these practices, and errors with manual data entry are common.
Is there a better, more seamless and automated solution? Looking at other industries such as retail, warehousing and discrete manufacturing it’s easy to see that there are certainly better methodologies. Of these, UHF RFID appears to be the best choice for asset monitoring in demanding applications.
Flying High with RFID
Since 2011, Delta Air Lines has installed more than 240,000 RFID tags on oxygen generators, life vests and cabin emergency equipment on all its aircraft. The result: The airline can now check the expiration dates of all oxygen generators aboard a 757 in less than two minutes—instead of the approximately eight man-hours it used to take to do this manually.
Although this not a process industry application, the requirements are similar to many industrial situations, proving the concept’s worth in dealing with critical assets.
A Process Industry Example
As an example, information about a valve can be automatically populated on a bar code or some other type of nameplate tag by the valve manufacturer. However, if the valve is in a difficult area to reach by a technician, it may require erecting scaffolding (Figure 2) to positively identify the asset.
Figure 2: Scaffolding or a ladder is needed to check the tag on the valve at top left center of the photo.
RFID provides a better solution in these and other demanding situations.
Requirements for an Industrial RFID Tag
Jelken says an industrial RFID tag should be rugged, have hazardous area certifications and resist harsh environmental conditions such as chemicals, dust, particulates, moisture, ultraviolet light, vibration and temperature extremes. And it should be able to be read at a distance.
For example, the Emerson UHF RFID Tag (Figure 3) has 1000 bytes of memory; FM, CSA, IECx and ATEX certification; IP68 and IP69K ingress protection; and is chemical, UV, moisture, temperature, vibration and flame resistant. It has -40 to +85 C operating temperature, and a read range of up to 25 feet line of sight.
Figure 3: Emerson’s Asset Management tag has a metal bracket that amplifies the RF signal, providing a read range of up to 25 feet.
A smart tag should have supporting software that allows a technician to quickly access any information needed in the field (Figure 4). The data on the tag should also be accessible by software platforms used for maintenance management, historization, diagnostics and other tasks
Figure 4: With supporting software, once a valve is identified a technician can access data from a mobile device, such as a smartphone.
The data residing on the tag provides value to field personnel, but the ability to automatically complement tag data with rich contextual information in real time greatly increases the utility of an RFID system. Data of interest to a field technician such as repair history, recommended spares, product documentation, walkdown results, link to order online, request service, etc. can be transmitted to a mobile device.
Accessing All Assets
One of RFID’s main uses in industrial plants is updating systems when assets have been moved, received or serviced.
For complete adoption, asset tags need to be available for all products and systems critical to the customer facility. This type of standardization is analogous to instrument communication protocols such as Foundation Fieldbus, which started with a single vendor and is now available to all at no cost.
If RFID was adopted across the industry in a similar manner, the savings to end users would be immense.
Jelken summarizes:
Paper-based maintenance and asset management is an unsafe, expensive, time-consuming and error-prone way to run a process plant. It inherently requires plant personnel to spend time in potentially dangerous situations. Of all the modern technologies available as a viable replacement, UHF RFID is the best option.