| 5.3 Image processing
5.3.1 Method
A standard system includes image recognition,
image processing and a control unit. The sensor unit is a
metal structure designed to fit easily into an extruding line.
It is equipped with a lighting system for homogeneous illumination
of the entire surface of the product. Three CCD array cameras,
offset at 120°, watch the running product and transfer
data to the processor unit. The recognise smallest defects
such as pinholes, changes of colour, neckdowns, lumps...
SIMAC® |
5.3.2. Advantages
The system analyses more than 2000
images per second. The smallest faults are caught, even with
high-speed lines, irrespective of their location on the product.
Each picture of a fault can be stored. These pictures can
be displayed and analysed later, e.g. during a night shift.
5.4. Photometric Method
5.4.1. Method
The highly sophisticated optical system
of the KW 32 Trio generates 3 thin light beams at 120°
in a common measuring plane. The three detectors that simultaneously
receive the light register its smallest variations due to
faults on the product.
KW 32 TRIO |
5.4.2. Advantages
Versatile installation possibilities,
detailed fault logging and insensitivity to external light.
Very simple operation and designed for many years of use.
A further development of a well-known technology; has been
reliably operating for decades.
6. Future-oriented ultrasonic
technology
Conclusion
The impressive advances in the field
of data acquisition have led to its splitting according to
the ever-increasing number of physical methods. Measurements
should always be carried out as close to the extruder as possible.
This allows a quick and effective re-centering while shortening
the path of the automatic thickness control. Contact with
the surface should not cause any unnecessary strain. Today's
ultrasonic methods offer a better product quality up to zero-defect
without additional investments.
|
