Seamless oil casingSeamless oil casingTempered glass is put into dipping stove and heated, and finally cooled down after heat preservation. After above processions, vulcanized nickel contained in tempered glass reaches the stable condition, and stress of interior glass tend to equilibrium, thus reduce self-destruction of tempered glass. Heat dipping can make particles or bubbles inside glass destroyed during processing. Thus self -destruction of tempered glass can be largely reduced after heat dipping treatment. Main factor for self-destruction of tempered glass