Architectural glass light in industrial factories. Annealed glass is glass without internal stresses caused by heat treatment, i.e., rapid cooling, or by toughening or heat strengthening. Glass becomes annealed if it is heated above a transition point then allowed to cool slowly, without being quenched. Float glass is annealed during the process of manufacture. However, most toughened glass is made from float glass that has been specially heat-treated. Annealed glass breaks into large, jagged shards that can cause serious injury and is considered a hazard in architectural applications. Building codes in many parts of the world restrict the use of annealed glass
Glass-to-metal seal thermal expansion. Then the edges of the strip also have to be knife sharp. The disadvantage here is that the tip of the edge which is a local point of high tensile stress reaches through the wall of the glass container. This can lead to low gas leakages. In the tube to tube knife edge seal the edge is either outside, inside, or buried into the glass wall. Another possibility of seal construction is the compression seal. This type of glass-to-metal seal can be used to feed through the wall of a metal container. Here the wire is usually matched