N
ovember
2014
101
THE Machines Yvonand SA
Article
Quality assurance and traceability
in drip irrigation pipe extrusion
technologies and production
By Eberhard Kertscher, director of board, THE Machines Yvonand SA, Switzerland
Line configurations
For simplicity reasons a full description is not given for a
typical production line for the extrusion and manufacture of
drip irrigation tubes. This can best be reviewed in the TEC
COM 87/13 (*1) and TEC COM 89/13 for Laser Marking on
the Fly.
The line layout (Figure 1) production and manufacturing steps
for drip irrigation tubes describes in general how the individual
quality assurance functions are interlinked between each of
the main components in the line.
All main process steps (from left to right) are key components
for full quality assurance, starting with labyrinth tape or dripper
sorting and insertion to tube or pipe extrusion and subsequent
emitter adhesion to the tube through to tape or tube vacuum
cooling, cooling and drying with subsequent high speed
punching, drilling or slitting and finally high speed automated
Industrial production lines for the manufacture of pipes,
tapes and tubes for drip irrigation application have
undergone extensive development over the past three
years. New technologies were presented and implemented
in the market place, both in the nature of the tubes,
tapes and pipes as well as in the actual processes and
manufacturing techniques.
Typical production speeds of 60m/min for round and flat
drippers were increased to some 300m/min along with
insertion rates of the drippers from 200 to 300/min to some
2,000/min.
The results were that new ways had to be adopted, for
example in sorting methods for this vast increase in dripper
quantity and the respective down-stream drilling or punching
for the accurate water outlet. Latest technology platforms
have been adopted quite unexpectedly and hitherto would
have been deemed unthinkable for such ‘simple products’.
A significant challenge was the adherence to quality
systems resolved with the use of the most modern, high
frequency, speed, precision and high resolution visual
camera detection systems along with the data processing
capabilities necessitated for these demanding applications.
New laser marking equipment was developed and
implemented that enables the assured and ‘permanent’
printing or marking of products.
All of this allows for a very high rate of productivity and
at the same time assures the highest levels of quality
standards.
turret winding of the finished product onto cardboard spools
or in the form of coils.
Laser marking
To date, printing onto the pipes was achieved primarily by
means of inkjet printing to a very limited degree. The problems
and challenges with such solutions and equipment are well
known.
One of the main challenges is centred on the actual adhesion
of the print to the tube surface. To obtain any reasonable
adhesion the surface of the substrate must be subjected to a
mechanical, chemical or other pre-treatment, typically a flame
or corona pre-treatment. This, however, throws up additional
technical challenges, not least the additional investment and
utilities infra-structure necessary for the corona treatment
equipment itself.
Figure 1: Production of drip irrigation tubes
