Glass Transition Test (TG)
Glass Transition Temperature is the temperature range where a thermosetting polymer changes from a hard, rigid or “glassy” state to a more pliable, compliant or “rubbery” state. Insulators which are exposed to a temperature below the Tg, exhibit higher physical strength and stiffness, as well as greater electrical insulation, dimensional stability and chemical resistance than they do above their Tg. So the insulation material will undergo Glass Transition Test to check that the temperature is below Tg.