TPT September 2012

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Technology News
September 2012 51
High resolution video monitoring
THE automation of welding is becoming
more widespread with a view to
increasing productivity and guaranteeing
repeatability and consistency of results
using more and more specific welding
procedures.
On this basis, operators play an
essential role in the supervision of
welding operations. According to
the complexity of the parts and the
importance of the task in question,
tracking during welding can be
automatic or carried out manually,
which of course implies continuous
visual monitoring.
In terms of the extent of assistance
required by operators, today, one
out of three installations is equipped
with a video monitoring system. The
main objective is often the quest for
comfortable working conditions so
as to avoid fatigue and maintain the
operator’s concentration. Therefore the
video monitoring system often remains
the only solution enabling us to face
difficulties related to difficult accessibility
or the environment close to that of the
welded joints.
Some of the most recurrent situations
concern for example the presence
of preheating, access restrictions
encountered in the case of narrow gap
grooves, internal weld configurations
as well as the proximity of high energy
welding arcs or radiation exposure
encountered by the human body in the
nuclear industry.
Polysoude has set up an R&D
programme in response to these
various applications destined to create a
panoply of industrial solutions.
The common point to all of these
variants is the control panel itself,
grouping together the useful commands
in order to optimise image adjustment.
This control panel is ergonomic and
perfectly adapted for welding operations.
It is each individual camera that enables
themultitude of possibilities for adaptation
to the environment in question.
As a general rule Polysoude
recommends the use of two external
cameras (one for a front view and a
second camera for a rear view). These
modules are equipped with a motor-
driven focus and an adjustable liquid
crystal filter. This functionality results
from a specifically developed technology,
enabling the operator to intervene during
the welding process and adjust the image
according to specific requirements. Each
module of the external camera contains
an integrated cooling system,
which protects it from arc radiation.
In the case of reduced radial
clearance, Polysoude proposes
a panel of welding torches
equipped with one or two micro
cameras (a classical narrow
gap torch, a narrow gap torch
with an oscillating electrode
and internal welding lances).
All of the functions are perfectly
integrated and protected to be
compatible with the welding
environment. They are cooled in
order to be able to resist external
temperatures as high as 350°C.
Optical fibre lighting and retractable
filters allow for verification of the
positioning before welding or the result
after a downslope of the arc. The
positioning of the filters is synchronised
with the start of the welding sequence.
Manually adjustable mechanisms for
the focal length are integrated into the
body of the torch and are accessible
from the exterior in order to facilitate
adjustment. These solutions represent
the best compromise in order not
to interfere with the gas flow, and
moreover, to have a better viewing
angle for monitoring of the impact point
of the wire, the electrode integrity and
sidewall fusion. The creation of made-
to-measure optics enable optimisation
of the magnification and the vision field.
Polysoude SAS – France
Email:
Website:
Monitoring the weld process
Flying shear cutoff
MILL Masters, a tube mill manufacturer,
has announced that a new flying shear
cutoff has been made available to its
customers.
The cutoff has the capacity to cut
6mm to 25mm diameter steel tubing
with a wall thickness of 0.25mm to 1mm.
Speeds of up to 15m/minute or 60 cuts/
minute can be obtained by using a single
die. Cut lengths are variable within a
range of 450mm to 6m. Lengths can be
changed on the fly, quantities can be cut
in batch, and recipes can be stored for
future applications.
A double cut (dimple free) system
is also available – one blade passes
across the side of the tube creating a
notch for the shear blade to pass cleanly
through.
The cutoff utilises electric cylinders to
propel the knife blade and the carriage.
Several benefits from using the
electric cylinders include much quieter
operation, reduced maintenance costs
and the ability to control the speed of the
blade as it passes through the tube. This
is crucial when cutting through stainless
steel tubing.
The speed of the cutting blade should
match the tube’s material properties
to minimise the cut from overheating.
When the blade cuts too quickly through
the stainless steel it has a tendency to
push material instead of shearing it.
Mill Masters – USA
Website:
Flying shear cutoff