IQTension - Revealing Uneven Tension Profiles of Paper Reels
by Hannu Linna
In June 1998 Valmet Automation launched its IQTension product
at the PulPaper ‘98 fair in Helsinki. IQTension provides a new
method of revealing uneven tension profiles in cross direction
(CD-profiles) of paper reels before they can cause any harm at
the printing press. The system was developed by Valmet’s various
units in close collaboration with VTT Information Technology.
Valmet is one of the world’s leading supplier of paper and board
machinery and related process control. So far Valmet Automation
has sold nine IQTension systems, mostly to paper mills outside
Finland. The first device was installed at Helprint Quebecor Oy,
the largest rotogravure printing house in the Nordic countries.
According to VTT Information Technology’s research results, the
tension profile of the paper reel is an important quality property.
There is a clear interdependency between the tension profile and
the runnability of paper and thus also the amount of paper wasted
at the printing press. The difference in the amounts of wasted
paper is enormous when comparing good and bad paper reels. A large
rotogravure printing house can lose tens or even hundreds of tons
to wasted paper because of poor tension profiles meaning great
economical loss.
During the development of Valmet’s IQTension, the tension profiles
of over 5,000 paper reels were measured at the Helprint Quebecor
rotogravure printing house. The experiment revealed that the tension
profile affected both the reel’s break sensitivity and the amount
of paper wasted during the printing process. The tension profile’s
minimum value measured at the beginning of the reel was the most
critical factor for the number of breaks. During a run, the number
of breaks depended considerably on how unbalanced the overall
shape of the tension profile was. There are significant variations
in the papers supplied by different manufacturers. The larger
the fluctuations in the tension profile, the higher are the percentages
of breaks. Harri Sundell, Production Manager at Helprint Quebecor
Oy commented: “This product marks the beginning of a new era.
Papermakers and printers can collaborate and use the information
supplied by IQTension to achieve better quality in printing and
less paper wastage”.
VTT has modelled the interdependencies between the different paper
properties as well as the interactions between paper characteristics
and runnability. The software, which makes it possible to take
into consideration also properties measured across the web (CD-profiles),
is currently customised for research purposes. It will, however,
be developed into a practical tool with applications in every-day
production. VTT Information Technology is a pioneer on a global
scale as far as advanced research into the runnability of paper
on paper machines and printing presses is concerned. VTT is also
studying how greater advantage can be taken of the enormous amount
of data measured from paper.
The first IQTension device installed in a paper mill is at UPM-Kymmene
Corporation’s Kaipola mill, where it has successfully improved
both production efficiency and paper quality. The installation
is also being exploited for research purposes.
IQTension was recently awarded the ATIP (Association Technique
de l’Industrie Papetière) innovation prize at the ATIP 51st Annual
Meeting in Grenoble, France. The ATIP innovation prize has been
awarded four times. This year more than 30 products were competing
for the prize.
Please contact:
Hannu Linna - VTT Information Technology
Tel: +358 0 456 5253
E-mail: Hannu.Linna@vtt.fi
