Glasstress Ltd. was formed on the basis of the Laboratory of Photoelasticity of the Institute of Cybernetics at Tallinn University of Technology. The personnel of GlasStress Ltd. has 40 years of experience in measuring stress in glass articles, especially in articles of complicated shape. For that we have developed modern measurement technology as well as automatic polariscopes which are easy to handle and can be used in the vicinity of the production line.
Traditional photoelasticity premits only qualitative estimation of stress in glass articles of complicated shape. Errors in peak stresses may be manyfold. Manufacturing of resistant glass articles demands accurate knowledge of the residual stresses in order to optimize the glass manufacturing technology.
For measuring stresses in axisymmetric glass articles a new method, based on integrated photoelasticity has been developed. The method permits the determination of the distribution of all the stress components in solid and hollow glassware. Regions with highest stress can be easily found. The method has been successfully used for measuring stresses in drinking glasses, bottles, neck tubes of the CRT glass bulbs, lamps, optical fibre preforms, etc., for many companies. New projects concern development of photoelastic tomography for stress measurement in glass articles of arbitrary shape and of a portable scattered light polariscope for thickness stress measurement in flat glass.
GlasStress instruments and measurement technology have entered numerous markets from containers and tableware to automotive and architectural glass. Initially, GlasStress supplied instruments for laboratory use. Developments now concentrate on higher volume lower cost stress analysis equipment that may also be implemented as quality control instruments at the production line.
GlasStress is now developing and providing real-time, on-line inspection equipment for the broader manufacturing sector. The AP-06C and now the SCALP-01 are playing important role in the quality control of glass and translucent products. GlasStress is working to improve its customers productivity and product quality.
Relationships have been established with major glass manufacturers to develop process control systems for the manufacture of containers, tableware, architectural glass and automotive glazing.