Page 42 - Glass Machinery Plants & Accessories no. 3/2017

DEVELOPMENTS AT THE COLD END
developments at the cold end
EVOLUTION therefore refine pack-to-melt ratio colour criterion had also to be
TOWARDS WIRE-EDGE while keeping the highest level of taken into account. Indeed, sev-
RIDENTIFICATION AND quality. The WEM principle ena- eral parameters generally affect
MEASUREMENT bles to obtain the evaluation and the standard detection of the wire-
A few months ago, Tiama was anticipation of production drifts, edge. The worst combination is
asked by a number of customers giving the opportunity to iden- flint glass, narrow neck bottles
to strengthen its capacity in the tify the presence of an acceptable- with a threaded finish, where so
detection of wire-edge and over- size artifact and, if need be, to many reflections and light paths
press defects. The challenge pro- undertake the corrective actions are present that they affect the
posed was to secure the detection to eradicate it completely from the ability to correctly read the wire-
and the characterization of this production process. edge defect presence. This is why
kind of defects. The need was not WEM was designed to be adapted
only to detect a defect but also to OPERATING PRINCIPLE to any colour of glass ware.
measure this defect and propose The aim of this new system is Associated with a mould num-
action towards it. to measure the height of any con- ber reader, the Tiama MULTI4
Knowing that wire-edge and tinuous protrusion at the inner with WEM inspection can then
overpress defects are often critical part of the finish. Combining sev- immediately communicate the
for the glass plant process, Tiama eral views of the finish through a presence of such a defect in a
has innovated to respond to this patented mirror adjustment, the given cavity or even inform of a
demand with a new patented func- WEM gives the exact value of tendency of good ware (commer-
tion called WEM, standing for the defect height for each con-
‘Wire-Edge Measurement’, to be tainer displaying a defect. The
installed on a MULTI4. This new innovation lies into the ability to The previous visualization of
feature enables to optimize detec- measure in μm the height of the defects provided access to
tion performance while keeping protrusion and give for the wire- defect presence only. With side-
wise visualization of defects,
the highest possible productivity edge and for the overpress – two the inspection also enables to
levels. It offers defect identification different types of protrusion in have defect height measure-
based on height measurement. No the neighborhood of the sealing ment. Threshold is set in order
compromise: glassmakers can pre- surface – a value to compare to to reject any inner protrusion
cisely qualify what the acceptable the acceptable threshold. above limit. False rejection rate
limit is for the defect height and When developing WEM, glass is kept very low thanks to the
accurate height measurement.
Global performance and pro-
ductivity is improved

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