process
control
By MARK WILLIAMSON
A new automation infrastructure – which replaced antiquated chart
recorders and analog controllers – has paid off handsomely
AUTOMATION REJUVENATES
PABCO BOARD MACHINE
I
t’s often the case that end use requirements drive the
need for improved quality and productivity of paper
and board production lines. When the end product
converting process takes a step change, the performance
of the entire production chain certainly must move up
a step in concert. To keep up with new, more rigorous
end-user demands, paper and board producers should
update their existing processes regularly and invest wisely
in new equipment and employee tools and skills required
to meet their customers’ expectations.
PABCO Paper in Vernon, CA, was confronted with this
challenge when PABCO Gypsum, its main customer and
sister company, increased the production of the gypsum
wallboard plant near the company’s Las Vegas, NV, gyp-
sum quarry by expanding to a new, high speed wallboard
line in 2005. PABCO Paper and PABCO Gypsum are part
of the Pacific Coast Building Products group, one of USA’s
leading suppliers of building products and services to the
construction industry.
The mill took a hard look at how to achieve the Bill Fraser: “In this difficult economic climate, this
automation system allows us to make changes that
increased production and better quality needed to meet reduced costs without sacrificing quality.”
the Las Vegas plant’s needs. Then it decided to invest in
improved process and product quality measurements, including popcorn boxes, brick pallet sheets, wine box
process stabilizing controls, and vastly expanded opera- separation sheets, tablet backing board, and specialty
tor information and decision-making tools supplied by cake and donut boxes. This production flexibility allows
Metso. Product quality variability is much improved. In the mill to adapt its product mix to market conditions
fact, customers rate the quality as the best ever. Produc- and adds to the mill’s viability in more difficult economic
tion levels are up significantly, and the costs of energy and times. The furnish is 100% recycled materials, much of
raw materials have been reduced. which is sourced in the Los Angeles area.
PABCO acquired the idled mill in 1984. Since the
acquisition and restart, the mill’s production facilities E N D U S E R S N E E D L O W E R VA R I A B I L I T Y
have been modernized in several stages to meet PABCO’s
wallboard production and quality demands. These up- PABCO Paper was aiming at much more than the extra
dates included a new wet press, a new winder and seven 7 production required to satisfy the wallboard production
Horne pressure formers replacing the original dry vats. requirements. As well as extra production the new gypsum
The 110-in. wire width machine produces 225 to 250 wallboard process required more stringent and consistent
tons/day of gypsum face and back linerboard and other quality. Mike Willoughby, vice president of product qual-
specialty chip board grades (from 16 to 40 point caliper) ity and paper manufacturing, states, “The new gypsum
that are used for a variety of commercial applications wallboard line drove the linerboard quality requirements.
34 July 2009 Pulp & Paper International (PPI)
process
control
For the wallboard process we need to produce uniform the refining energy control loop. The analyzer has three
appearance, sheet flatness,