2 Water for life requires inventiveness I Daio Paper Mishima ... - Voith

worst case. Spreader rolls counteract
these effects. This is a working principle,
but also goes hand in hand with
high maintenance and service costs.
Conventional spreader rolls can
be replaced by rigid rolls
Thanks to the WebTense lamella roll
cover, conventional spreader rolls in
coater machines and calenders can be
replaced by rigid guide rolls today.
WebTense is applied to a rigid steel roll
(EvoRun) or carbon fiber composite roll
(CarboRun). Web tension forces the
lamellas to lie down and to the side,
thus achieve the effect of spreading
the sheet. Depending on the specific
application, WebTense can be made of
rubber, polyurethane or high temperature
resistant rubber.
The advantages of WebTense
There are many advantages of replacing
conventional spreader rolls with
WebTense.
• A simple construction – a rigid roll
core instead of multiple segments
WebTense can be made of rubber, polyurethane or
high temperature resistant rubber.
26 I 2008 I Voith Paper I twogether
• Easy maintenance – no complex
mechanical service of segment
bearings
• Elimination of sealing and segment
bearing leakages
• Energy saving – less drive capacity
necessary
• Larger paper wrap angle (15°-180°)
possible
• Less space required because the
conventional spreader roll, up- or
downstream guide roll, can be
replaced by WebTense
• Vibrations can be eliminated with
the use of CarboRun
Depending on position and application,
WebTense reaches a life time of
one to several years. The cover must
only be replaced when the lamellas
lose their elasticity and thus diminish
the spreading effect.
Replacing a conventional spreader
roll with WebTense needs some
engineering work. The web guidance
and the specific demands have to be
exactly analysed. The design of the
roll cover has to be tailor-made for
each application.
Contact
Deformation of the cover in radial direction.
Max Albrecht
Rolls
max.albrecht@voith.com
PRoDUCTs
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