Helping to
Improve Quality
Huhtamaki (formerly Van Leer — Plastona), produce plastic film for food
packaging. They have a number of machines which are basically of similar
design, starting with an
Extruder and Die Set leading into a Cooling/Polish Roll
system and thereafter into accumulators for subsequent
reeling into storage rolls, or onward processing into carton forming
machines.
Forming the final carton or food container product is critically dependant
upon the film quality and thickness, therefore
Huhtamaki have introduced the latest gauging technology to monitor the
machines for dimensional accuracy. The next step was to take control of the
process and be able to offer adjustment or change to keep film thickness
within tolerance from product to product.
The Cooling/Polishing Rolls are gearmotor driven as are the Haul-off Nip
Rolls some distance down the machine.
Clark Components replaced both these drives with Closed Loop Vector
Gearmotors plus AC Inverters and provided adjustment in the form of a
Percentage Draw between the two. The Cooling Roll drive acts as the master
and takes in the line speed reference and the Haul-offs act as a
follower with the percentage draw/pull offset controlled by the machine
operators.
The product quality improved dramatically and eliminated several problems
Huhtamaki were having within the following film forming processes due to
poor quality coming from the film process itself.