Annealing is a process of slowly cooling hot glass objects after they have been formed, to relieve residual internal stresses introduced during manufacture. ... Glass that has not been properly annealed retains thermal stresses caused by quenching, which indefinitely decrease the strength and reliability of the product.

How does a glass Annealer work?

In technical glass production, molten glass is pressed and it rapidly cools as it is removed from the mold. This rapid cooling creates internal stresses within the glass piece. When the glass finally cools to room temperature, stresses in the glass can potentially cause spontaneous breakage.

What does an Annealer do?

Metal fabricators use annealing to help create complex parts, keeping the material workable by returning them close to their pre-worked state. The process is important in maintaining ductility and reducing hardness after cold working. In addition, some metals are annealed to increase their electrical conductivity.