Consequently, low tonnage container and tableware manufacturers have not had access to the level of glass conditioning control enjoyed by larger tonnage producers.
The new Emhart Glass 240 Forehearth has been specifically designed to radically improve the performance of low tonnage, 16-inch wide forehearths. By adapting the proven 540 Forehearth superstructure cooling system, the Emhart Glass 240 provides fully automatic longitudinal muffle cooling control. This, in combination with automatic combustion control, provides a powerful thermal conditioning system.
The Emhart Glass 240 Forehearth incorporates cooling plates embedded in the forehearth superstructure above the central glass stream. The rear faces of the plates are covered by a longitudinal refractory muffle extending over the length of the cooling zone. The muffle is fitted with an automatic, forced convection air cooling system.
In operation, the central glass stream radiates heat to the cooling plates that in turn are cooled by the airflow passing over the top faces of the plates. By controlling the airflow through the muffle, the amount of heat taken from the glass is dependent on the temperature of the cooling plates. Therefore, the central glass stream temperature and thermal homogeneity of the glass can be controlled. Since the cooling plates extend over the central section of the forehearth roof, the cooling effect does not extend to the side areas of the forehearth, which are controlled by the combustion system.
The Emhart Glass 240 Forehearth is ideally suited to those operating within the tonnage range of 3 to 20 tonnes per day. Due to the increase in cooling capability, changing to the Emhart Glass 240 will provide improved glass conditioning and accommodate greater tonnage and gob temperature ranges than existing systems.