ABB, Zurich, Switzerland, has ensured that an Ahlstrom filter paper production machine in the U.S. can avoid costly downtime by providing an innovative upgrade for its integrated control system and scanners. The Ahlstrom plant operates a variety of ABB scanners and a quality control system that span both early and recent generations. Some of the scanner equipment was installed nearly three decades ago and is now benefitting from computer and electronics improvements that have been introduced gradually over the years.

The latest upgrade is intended to deal with downtime risk due to aging parts while delivering better health diagnostics with improved process management and control. However, planning for this upgrade was not as straightforward as the previous ones.

Ahlstrom was aware of ABB’s lifecycle management model, which tracks a product throughout its useful life in four phases from "active" to "classic", through "limited," and then finally to the "obsolete" lifecycle stage. As such, Ahlstrom knew that, within a short time, one of the two installed measurement scanners would move into the obsolete phase. In this final lifecycle stage, the scanners and sensors would no longer be feasible to support, potentially resulting in extended machine downtime.

The existing, newer scanner and older U-Frame scanner were considered for upgrading to the latest Network Platform generation electronics. While upgrading the newer of the two scanners is relatively easy, this is not so with the early generation U-Frame.

Ahlstrom greatly valued the U-Frame design due to its mechanical integration into their machine and its easy access. Changing to a modern O-Frame structure, by replacing the scanner, would not have provided the final result Ahlstrom needed—newer measurement technology packaged in a similar form factor to the existing U-Frame. Additionally, it would have cost the manufacturer four times as much to upgrade the system since doing so would have required significant machinery modifications and expensive machine downtime, not to mention delays caused with the associated bidding process.

"We asked ABB if there was an alternative approach; one that avoids closing the plant for a significant length of time and that does not encroach on the present line’s footprint," said an Ahlstrom engineer. "And, thanks to the ingenuity of the ABB engineers, they said that, on this occasion, there was."

ABB’s systems engineering group in Ohio devised a solution that allowed the Network Platform electronics to be mounted within the existing U-Frame enclosure. This is the first time a Network Platform upgrade is being performed on a U-Frame scanner. "We were able to consider such a conversion here as parts of the U-Frame had already been upgraded many years ago—also a first," explained Trent Miller, ABB’s Systems account manager. The second part of the U-Frame overhaul was to replace the outdated basis weight sensor with the most current version. ABB engineers demonstrated their resourcefulness by designing the brackets and slides needed to retrofit the existing U-Frame head package to accommodate the new style basis weight sensor.

In addition to allowing faster and more effective maintenance, other advantages of upgrading to the Network Platform architecture include higher process measurement resolution, faster communication of information to the control system, and the ability to use more sophisticated measurement technologies in the future.

At the same time the Quality Control System 800xA, used to monitor and analyze data from the scanners and control various parts of the process, will be upgraded to the latest version. The upgraded system was running Windows XP and Server 2003 which is no longer supported by Microsoft, thus making it more vulnerable to security threats. The new software allows better operator interface and control capabilities.

The first installation phase will begin this August, with the second phase due in November.