TPT November 2015

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Technology News
26 November 2015
Consistently high product quality
with variable material input
THE basic concept behind the “Shape”
technology module developed by the
SMS group is high-quality production
even with fluctuations in the ingoing
material. The system comprises three
modular sub-systems, ShapeBase,
ShapeView and ShapeControl, and is
designed to achieve optimised forming
of longitudinally welded large-diameter
pipes during the JCOE® process. SMS
aims to give customers a tool to help
them meet the constantly growing
market demands on quality, but without
sacrificing productivity.
The starting point for the latest
development of ShapeView and
ShapeControl was the ShapeBase
computation module that has already
been in use since 2013 for calculation
of the process parameters for JCO® pipe
forming. The JCO® pipe forming process
is characterised in particular by its high
flexibility and the correspondingly broad
production spectrum, with pipe diameters
from 16" to 64" (406 to 1,626mm) and
wall thicknesses to over 45mm.
In order to optimally adapt the
flexible parameters of the pipe forming
press to the planned production, SMS
developed the ShapeBase software
for its customers which enables the
customer to have basic machine settings
calculated by the program displayed:
these include the tool radius to be used,
the lower tool gap to be set and the
optimum number of bending steps.
On the other hand, reliable starting
parameters for the bending process are
calculated and output on the basis of
these machine parameters. In particular
the positions of the individual bending
steps on the plate and the corresponding
stroke of the bending tool are calculated
in advance. The calculation of the tool
stroke has to take into consideration not
only the current bending contour, but
also the spring-back of the material after
bending that is essentially dependent
on wall thickness, yield strength and
modulus of elasticity.
The result of the ShapeBase
calculation that can be carried out
offline on any production planning PC is
therefore a theoretical recipe for forming
of the desired pipe.
Certain parameters, however, cannot
be taken into account in the advance
calculation. These include in particular
fluctuations in the wall thickness and
in the yield strength of the ingoing
plate that may have larger or smaller
tolerances. In practice, the process
data – and in particular the stroke of the
forming tool – are therefore adapted to
the current plate charge from pipe to
pipe. Until now, radius templates have
generally been employed at the start-up
of production, but their use is relatively
time-consuming even for experienced
operators. If there are fluctuations
within the plate charge, however, these
are difficult to detect and are almost
impossible to compensate manually.
Furthermore, minor inaccuracies
in the plate positioning can lead to
deviations during forming. At this point
the new ShapeView system offers an
optimum complement to the theoretical
calculations fromShapeBase. After each
forming step, the resulting pipe contour
is measured in detail in a defined cross-
section using laser light section sensors.
The system does not just provide a
digital template – it “thinks” one step
further in the interfaced ShapeControl
module. The measured contour is
compared here with the theoretically
expected contour.
If deviations are discovered,
ShapeControl starts a correction
algorithm which supplies the forming
press with an adapted tool stroke for
the next forming step. In this way a
closed control loop of measurement
and correction is created that leads to
optimised forming of each individual
pipe. This correction algorithm must
naturally give consideration to the
current machine parameters – in
particular tool radius and lower tool
gap – in order to be able to calculate
appropriate correction values. The
Shape system therefore communicates
constantly with the machine controller
to exchange important process
parameters. A dedicated database
allows the Shape system rapid access
to previously calculated data sets
and offers the operator a convenient
overview of existing production recipes.
Extensive trialsona laboratorymachine
at the SMS group in Mönchengladbach,
Germany, demonstrated the function of
the control algorithms and the correct
data processing in the whole Shape
system. Since the completion of the
trials on the laboratory machine, the
system has already been sold several
times for industrial application. The first
commissioning at Corinth Pipeworks
confirmed the high expectations. Even
before installation of the ShapeView
system, the offline calculations
provided reliable process parameters
for straightforward technological
commissioning of the forming press.
With the Shape technology, the SMS
group offers its customers a tool to
help them meet the constantly growing
market demands on quality, but without
sacrificing productivity. The Shape
technology is configured such that it can
also be retrofitted in existing JCO® pipe
forming presses.
SMS Meer GmbH – Germany
Fax: +49 2161 350 1862
Email:
Website:
Shape technology from SMS group