What is the mechanical stress in glass bottles

In the process of production, glass bottle subjected to intense and uneven temperature variation, thermal stress is produced. The thermal stress can reduce the glass strength and thermal stability. Thermoforming products if without annealing make its natural cooling, is in the process of cooling, storage, use, produces the crack.

annealing is to eliminate or reduce the thermal stress in glass products to the allowable values of the heat treatment process. Thin-walled products ( Such as light bulbs, etc. ) And glass fiber after forming due to thermal stress is small, in addition to properly controlled cooling speed, generally no longer annealing. If the glass surface layer have regular and uniform distribution of compressive stress can improve the glass strength and thermal stability. Glass quenching strengthen is the application of this principle.

glass bottles of stress in general can be divided into three categories: thermal stress and structural stress and mechanical stress.

the thermal stress in glass bottles is due to the temperature difference and the stresses are present in the glass, according to its characteristics can be divided into two categories, temporary stress and permanent stress.

mechanical stress caused by the external force on the glass in glass bottle stress, disappear when the external force to remove the stress, the stress according to mechanical stress. In the process of production, if excessive mechanical force to bear on glass will make the glass broken.