Requirements to purity and quality of glass

Butyl from double sealing is permitted max.. 2 mm into the unit from the spacer profile..Complaints concerning impurities in glass will be evaluated according to the below procedure on the basis of which it will be decided if they are immaterial i.e. inherent in the material and as such not covered under the warranty – or if they are so material as to qualify for a replacement of the glazing unit.

READ MORE: visual-deviations-in-quality-in-insulated-glass-units.pdf

Breakage in insulating glass units

There always exist several basic rules which prove out for the cases with non-tempered glass and thus they should be taken into account.

Three rules of breakage:

  1. Breakageg is always expanding in the direction of spread.
    If such expanded breakage is traced back, the primary breakage an splitting centre is reached.
  2. A crack can never overleap the existing crack. 
    A crack ends at the place of reached another crack. This fact often enables to establish the sequence of crack emergence as well as place/cause of the primary crack. This feature is used by glass specialists for "catching" of cracks.
  3. The average number of cracks depends on the degree of load at the time of cracking. 
    A denser network of cracks is usually formed when the glass has to hold a bigger load than vice-versa.
  • Thermal cracks. Read more
  • Risk factors for thermal cracks. Read more
  • Mechanical strokes. Read more