Set-point reduction
Rules in blown film extrusion
On production of blown film in single layer or multi-layer technology, yield and quality control are the two major requirements which have to be achieved.
In detail it means:
- Proof of thin layers (1...5µm) inside the composite
- Savings in material usage by reducing set-points to a minimum by providing accurate layers.
- Direct and continuous blending of 2 ... 7 components on the extruders usually with a free-flowing main component.
Multi component blending unit for film
Features
As shown the equipment used in film extrusion is build up with a free flowing main component delivering at least 65% of main material in direct blending.
Material conveyors can be part of an integrated unit saving investment and space.
The unit can be optimised on non-interrupted switch over form one product to another. It is important that no material remains in dead corners when the new recipe starts.
On the PLC a special procedure makes sure, that all components come to an end synchronously and with less surplus of production. That saves material and a lot of time for the change..
Refurbishment of blown film lines
Scope
Closed-loop weight-per-meter control has been used in blown film lines for many years. Many existing systems are getting on in years and are no longer state-of-the-art. Resultant electronics malfunctions, control problems and substandard performance cause frequent headaches for production operations.
There is a solution available. We can refurbish single components or retrofit your entire system if required by the problems at hand. The core elements of our systems are the Siemens PLC S7-1200 and the GraviProfi 2408. Our systems are compatible with all weigh hopper makes equipped with strain-gauge load cells. For systems requiring new weigh hoppers, we offer our BTW weigh hoppers with outstanding overload protection.
