|
|
|
|
|
|
|
|
Mode of operation: |
|
|
Depending on the task, the roundtable system is either equipped with rotating plates or article
holders, onto which the glass items are placed, i.e. for fire-polishing or for pre-heating and forming
(punching). It may also be equipped with two article-holders for each station for holding the top and
the bottom part of glass items for either separating (burning-off) or joining (welding) the two parts
(i.e. blown bowl and pressed stem or foot) or for forming the softened glass (stretching and twisting
of stems).
Highly flexible components perform all special functions. The processing cycle - which is based on the
temperature of the glass item necessary for processing - can be optimised according to the individual
requirements, since the MMC-software allows to achieve an optimal interaction of the servo-motor
based table rotation and the performance of each station. The burners as well as the articles can be
precisely positioned or moved in each processing step. All movement parameters as well as the tools
for forming the softened glass (punching, calibrating etc.) are controlled by the MMC-software. The
processing cycle typically includes functions like loading, pre-heating, flame-processing, forming of
the softed glass, cooling and/or unloading.
|
|
|
|
|
|
|
Fire-Polishing / Rim-Glazing |
|
|
Application: |
|
|
Fire-polishing of surfaces and handles mainly aims at eliminating press seams and at increasing the surface quality. Rim-glazing on the other hand allows to process the top or cap of blown glass items after the cold-cutting process if the glass items are not acid-polished.
|
|
|
|
|
|
|
|
Mode of operation: |
|
|
There are three principal options for the layout of the fire-polishing system:
First: the glass item is entirely fire-polished by large burners and is moved through one or more
fire-polishing stations subsequently until the required result is reached.
Second: each section of the glass item is fire-polished subsequently while manually height-adjustable
burner systems cover different zones of the rotating glass item in subsequent stations. A turning
device allows to reach all zones equally and a double-headed burner, which moves in and out, allows
to fire-polish handles.
Third: a computer-controlled vertical movement of the burner allows to individually adjust the
fire-polishing time for each zone of the rotating glass item. If oval or rectangular glass items have
to be fire-polished, the servo-motor based table movement, which allows to perform a nearly linear
backward and forward movement, may be used to perform a horizontal movement in addition
to the article rotation and the vertical movement of the burner system. These synchronized movement
parameters allow to follow the contour of the glass item. One or more stations may be equipped with
a computer-based height-adjustable burners.
For rim-glazing, the height of the burner is adapted to the height of the glass item and the glazing result
is regulated by the fire-polishing time. |
|
|
|
|
Features: |
|
|
|
|
|
|
|
Burning-off |
|
|
Application: |
|
|
The burning-off unit has been designed for removing the top or cap of blown articles. Burning-off the top leaves the rim slightly thicker than the wall, and - given this visual implication - it is generally used for glasses with a safety rim and for glass items which incorporate this rim into their design.
|
|
|
|
|
|
|
|
Mode of operation: |
|
|
The blown glass item is transferred to the roundtable of the burning-off unit, where the base is held by the upper article holder. A ring-shaped cutting torch burner is closed around the glass item, while the
top or cap is gripped by a lower gripping device. The burner heats the glass until the top can be pulled
down and the rim can be fire-polished. After cooling, the glass item can be taken out and transferred
into the annealing lehr. |
|
|
|
|
Features: |
|
|
|
|
|
|
|
Welding |
|
|
Application: |
|
|
The welding process allows two different applications: welding is necessary for joining the (pressed or
injected) stem or foot with the blown goblet bowl of stemware. But the welding process also allows to
weld more complex shapes such as round, oval or rectangular rims. This process is used for welding
architectural glass bricks.
|
|
|
|
|
|
|
|
Mode of operation: |
|
|
In a completely automatic stemware production line, the bowl (or bowl complete with vacuum-drawn
stem) is produced on the blowing machine, while the foot (or pressed foot complete with stem) is
produced on a press machine. Both items need to be joined together and this is done by welding.
The welding is either done on a separate roundtable system into which the bowl and stem or foot are
loaded. Alternatively, the welding can also be done in the welding station which is integrated into the
blowing machine. The stem or foot is transferred into the blowing machine from the press machine
and is welded to the bowl (complete with stem). A double-headed burner heats both parts at the
welding interface surface. When the surfaces reach the correct temperature, the bottom part moves
vertically upwards until contact between both surfaces takes place. After cooling, the complete
stemware is taken out for annealing. The same system may also be applied for welding glass bricks
for architectural use. While the tools (article holders and burner system) vary from the stem-welding
system, the processing procedure is basically the same. A special layout for the tools, especially the
burner systems, is decisive for the quality of the welding joint. |
|
|
|
|
Features: |
|
|
|
|
|
|
|
Stretching and Twisting |
|
|
Application: |
|
|
Depending on the manufacturing process, there are two fields of application for the stretching equipment:
For stemware which is produced in one piece already in the blowing machine by squeezing a
foot out of the vacuum-drawn stem, the stretching process is necessary to transform the thick and
short stem provided by this process into a longer and slimmer stem. For pressed stems or vacuumdrawn
stems (with a pressed foot welded onto the stem) special design requirements might make
the stretching process necessary in order to achieve even slimmer and higher stems than is possible
by pressing or vacuum-drawing.
The stretching equipment also allows to produce twisted stems by applying lacing and winding techniques.
Thus the range of designs available in a fully automatc stemware line is essentially extended.
|
|
|
|
|
|
|
|
Mode of operation: |
|
|
The stem is pre-heated while the top and the base of the glass item are held. The two article holders
rotate synchronously. The vertical movement of the lower article holder allows to stretch the stem as
soon as the glass is sufficiently heated and soft enough for forming. The softened stem may also be
twisted by changing the rotating speed of the lower station. |
|
|
|
|
Features: |
|
|
|
|
|
|
|
Punching / Fire-Cutting |
|
|
Application: |
|
|
Flame-processing in combination with mechanical tools allows to punch holes into the hot glass,
which is necessary for light-sources, mixing equipment etc.
|
|
|
|
|
|
|
|
Mode of operation: |
|
|
A cylinder, which performs a vertical movement, punches a hole into the glass item after the glass
item has been pre-heated. The part, which will have to be punched out, has been carefully conditioned
so that a defined cut is guaranteed. The hole is fire-polished, calibrated and cooled in subsequent
processing steps. |
|
|
|
|
Features: |
|
|
|
|
|
|
|