Glafo, PG Vejdes väg 15,
Vejdes plats 3
Tel: +46 10 516 63 50
a map at the
"about Glafo" page.
and strength assessment of flat glass
Glafo has purchased a meter for direct strength measurement and strength
assessment of float glass, in the form of a SCALP-04 (Scattered Light
Polariscope) from GlassStress Ltd.
the ways in which the meter can be used include:
- monitoring the stresses that occur, and how they change, in glass
when subjected to mechanical load;
- providing warning of unbalanced load in a structure;
- checking the degree of tempering and the tempering quality;
- investigating the stresses in heat-strengthened glass;
- measuring residual stress from manufacturing.
and coated glass
The instrument is also capable of stress measurements in curved glass
sheets. There are applications within automotive glass, glass for interior
fittings, architectural glass and a range of domestic glass. Several
different types of coated glass can also be measured. Float glass can
be measured from either side, regardless of the tin coating.
The meter is held against the glass, and sends a beam of polarised laser
light at an angle through the glass. Variations in the intensity of
the scattered light are detected, from which the instrument calculates
the stress profile in the glass. Measurement takes only a few seconds.
Anisotropic stresses may be determined (different stresses in different
directions) by measuring at the same position in a number of directions.
of the SCALP polariscope.
A typical stress profile in thermally toughened 5 mm thick glass. Tensile
stresses (positive values) in the centre of the material change to compressive
stresses (negative values) towards the surfaces of the glass. Compressive
stresses at the surface are about 145 MPa, making the glass about five
times stronger than ordinary annealed glass.
Contact person: Maria
Lang, +46 10 516 63 56, firstname.lastname@example.org