is thermally toughened safety glass?
toughened safety glass is a heat-treated glass which we can
produce in either flat or curved form. It has the following
- About 3 times higher resistance to mechanical shocks compared
to non-toughened glass
- About 3 times increased thermal resistance characteristics
compared to normal glass
- Safety glass, i. e. in case of breakage, it decays into
small blunt fragments, then reducing the risk of injuy.
the process of thermal toughening, a readily cut and treated
glass sheet is heated up to approx. 650＜ C and then quickly
cooled down by means of cold air. The inner part of the glass
cools down more slowly than the external surface. The inner
part still contracts when the surfaces of the glass have already
solidified. A compressive stress develops at the surface of
the glass, in the inner glass there is a tensile stress. Thermally
toughened safety glass cannot be treated further after the
use the following glass types as our basis material:
- coloured glass
- cast glass
- coated glass
luminaires and lamps
- household appliances
aspects have to be considered when using thermally toughened
The linear heat expansion coefficient is 9 x 10-6 K-1. A rule
of thumb: An increase of temperature by100＜C causes an expansion
of approx. 1,0 mm/m
When installing thermally toughened safety glass direct contact
with metal is to be avoided because "heat bridges"
can develop. In order to balance the unevenness of the supporting
surface and the different heat expansion coefficients please
use soft rubber.
Principally, the following minimum distances are to be respected
when planning the positioning of the holes:
a) Glass edge to edge of hole = double glass thickness
b) Edge of hole to edge of hole = double glass thickness
c) Holes at the corner: Should one of the distances between
edge of the hole toone glass edge be less than 35 mm, so the
difference of the distances to theedges has to be at least
The diameter of the hole has to be at least the thickness
of the glass!
The glass sheet principally has to be installed in a way that
the load / stress is distributed equally. Screws and fixings
must not load the glass punctually. The screwing is to be
Cuts into the glass need to have a radius equal to or bigger
than the thickness of the glass.
Non-observance of these rules leads to a lesser strength of
the glass! We principally examine every single case if the
glass with the requested treatment can be thermally toughened.
mainly produce according to your individual requests.
produce our thermally toughened safety glass in dimensions
between Dia:10 mm and 1000x800 mm in thicknesses of 3, 4,
5, 6, 8, 10, 12, 15, 19 and 25 mm. The maximum weight of each
sheet is 200 kg.
cut our glass on round and form cutting machines as well as
on CNC-cutting tables. The minimum cut size is diameter 10
the production of thermally toughened safety glass, the minimum
requirement of edge finishing is an arrissed edge. In many
cases, however, we recommend a ground edge due to stability
reasons. The edge finishing is made on round and form grinding
machines, double edgers as well as on CNC-working units. Our
standard edge finishing is the C-edge (= pencil edge). On
request, we can also produce other edge forms such as straight
edge with arriss, bevelled edge and facets.On basis of ground
edge,we make farther machining to provide polished edge, which
is the best finish of edge.In this way, you can see throught
from the side of glass.
holes in the glass are produced with tolerances different
from those known of metal working due to the characteristics
of the material glass. Glass is first slightly drilled from
the bottom and then drilled through the complete glass from
the top with a hollow diamond drill. Holes are generally available
in diameters of 4 to 240 mm. Bigger hole diameters and inner
edge treatment such as polishing are possible on request.
make decoration of the glass surface by silk screen printing
with ceramic colours. The colour is first applied to the glass
surface, dried up and finally, during the process of thermal
toughening, it melts with the glass so that a decoration which
is resistant to scratches is produced. Apart from ceramic
colours, organic glass colours may be used.
is blown on the glass surface with a fan. The sandblasting
can be made completely or partially onto the glass surface.
from these standard treatments, please inform us about your
requirements. We will be pleased to find a solution for your
our standard, we pack in between glasses with white paper.
We can deliver you reusable or non-reusable transport packaging
which is subject to agreement. Furthermore, individual packing
solutions are possible.