Page 40 - Glass Machinery Plants & Accessories no. 3-2021

PROCESS INNOVATIONS
Process innovations
GMP&A: By this reasoning, GMP&A: Which control loops GMP&A: And at the Cold End?
then, the measurements would do you mean? MK: The manufacturing process
ideally have to take place at the MK: Different sensors are also is completed when the glass con-
Hot End? used at different locations for the tainer passes the annealing lehr. The
MK: Precisely! That’s not so different process sections. They Cold End doesn’t deal with control-
easy, though, because many of are then used to influence param- ling the process. Here I should
these measurements are contact- eters of the gob, the parison mention the automatic check,
ing measurements. And when I or the bottle. Starting with gob using sample containers, to verify
contact a hot bottle with a meas- forming, you use a gob camera to whether the inspection machines
uring tool, it gets deformed and adjust and control gob shape and are correctly set. However such
becomes unusable. We still lack a gob weight. Gob temperatures, downstream processes as printing
solution to how it might work to too, can be measured to influence or surface treatments for increasing
turn a hot bottle and, for exam- the spout temperature within the the strength can also be measured
ple, to measure wall thickness. feeder. On the blank side, gob and controlled.
That’s unrealistic at the moment. delivery into the blank mould can
Today, we want to measure be detected and adjusted. The GMP&A: What role is played
the parameters of the forming tool temperatures on the blank by glass bottle weight and shape?
process directly - keeping them side (blank mould, neck ring and MK: In the 1990s, a price war
constant within narrow limits. plunger) can also be measured broke out for disposable packaging.
We use infrared cameras at the and controlled. Already today, In order to save on raw material,
Hot End to more swiftly identify infrared cameras on the machine energy and transport costs -but also
deviations in the process and, conveyor are frequently used to to reduce the charges to the dual sys-
above all, to neither exceed nor measure wall thickness distribu- tem for disposable bulk items- pro-
fall below the limits - all the while tion and detect global errors. jects have been launched to reduce
taking immediate countermeas- Optical cameras are planned on the weight of glass containers. That
ures. This technology is called the machine conveyor for meas- means producing with thinner wall
‘Hot End Closed Loop’. Ideally, uring and controlling the con- thickness. Heye has a very big
non-contact sensors control and tainer geometry as well as detect- advantage with its experience from
regulate the process. ing glass defects. H1-2 technology. As such it was

Smartline2 Cold end inspection machine

38 GMP&A 3/2022