Glass Annealing Temperature Tester (Annealing Point and Strain Point)

The SJY-I measures the annealing point and strain point of glass by the fiber drawing (pulling) method under programmable furnace temperature control. During testing, a uniform glass fiber is subjected to a defined load while the furnace cools at a specified rate, and the instrument detects the temperature at which the elongation rate meets the criteria for the annealing point and, by extrapolation, the strain point.

This method helps quantify and manage internal thermal stresses formed during glass forming, which can reduce mechanical strength, thermal stability, and optical uniformity. The system follows ASTM C336 as well as SJT11039-1996 for electronic glass and JC/T752-1996 for quartz glass, supporting process optimization and compliance in production and laboratory environments.