Distributed control system with benefits

When is a new equipment installation more than just implementing new devices? When it delivers benefits beyond and outside the areas you originally planned. When is a technical partnership more than just working together? When your outside service engineer becomes part of your staff and a valued friend.

All this happened at Rand Whitney Containerboard's mill in Montville, Connecticut, when it recently replaced and upgraded the distributed control system (DCS) on a mini-mill it built in 1995. This mill feeds old corrugated containers (OCCs) from the New England, New York and Boston areas into one 185-in. machine running at 1,500-2,250 ft/min to produce 655 tons per day of regular and high-performance linerboard products. The machine runs continuously in 12-hr shifts and is manned by 105 employees organized into four crews. Rand Whitney is a division of Kraft Group.

“This isn’t the largest plant or machine, but it fits the size of the market we serve,” says Rick Hartman, Rand Whitney's general manager. “However, the mini-mill concept means we have little or no room for storing raw material or finished product, so we have to run very fast and in a tight window. So when our former controls became obsolete, our management evaluated a lot of solutions and chose ABB's System 800xA because it could be easily integrated with what we needed in our DCS, our quality control system (QCS), and with ABB's own drive systems, which were already on the machine.” Rand Whitney's machine and related equipment include about 500 process control components and about 1,300 I/O connections, while its QCS includes scanners with weight and moisture sensors and optimization controls.

Besides partnering with ABB on the equipment installation, Rand Whitney also relied on ABB to provide engineering support it didn't have in-house. “We used to have some variances in operations and product quality per shift, but our ABB service engineer, Jason Belding, also helped us do some coaching up in the control room and really became part of our own engineering team,” explains Hartman. “Now we're getting three or fours days of consistent production at a time. This is really how we're winning economically.”

Thanks to the consistent operations aided by ABB's System 800xA DCS, Rand Whitney's quality gains include a 20% weight profile improvement, 22% moisture profile improvement using 39% less water from a re-moisturizing actuator and 18% fewer quality losses. Operational improvements include 35% faster grade change and product type changes and 35% faster recovery from sheet breaks.

“I think the gains we're seeing now are exceeding what the planners thought they would get at the beginning of this project,” adds Hartman. “This system lets us connect all sorts of people with information they didn't have access to as easily before.”

For instance, System 800xA enables new best practices by displaying functional description pages of Rand Whitney's machine performance, showing group controls of the whole application and providing performance and device health information from about 200 intelligent transmitters and other devices. Besides consulting Belding, Rand Whitney's engineers also are using System 800xA's online supervisor functions to document their activities and then prioritize and check off completed tasks.

“ABB has given us huge support and is really an extension of our good mill team,” adds Hartman. “This partnership has been integral to us achieving a 3% improvement in overall machine effectiveness and a 1.2-year return on investment.”