Nonaxisymmetric residual stress distribution in axisymmetric glass articles

Residual stress measurements in many bottles, tumblers and in other axisymmetric glass articles by using integrated photoelasticity have shown that the residual stress distribution often deviates from the axially Symmetrie one. A method is developed which enables determination of nonaxisymmetric residual stress distribution. A computer-controlled polariscope has been developed for automatic measurements. Several examples of residual stress distributions, which deviate strongly from the axisymmetric one, are given. It is shown that deviadons from axial symmetry lead to less favorable distribution of the residual Stresses; e.g., they may lead to tensile residual Stresses on the external surface of bottles.