04/08/09 General News
CHINA - forehearth contrasts
Two recent SORG forehearth installations in China demonstrate the range of applications that our Glass Conditioning Department deals with.
One installation is used to press small reflectors for halogen lamps in hard borosilicate glass with an expansion coefficient of 37 x 10-7. The typical gob weight is about 25 grams, the forehearth bowl temperature is around 1400 °C and the pull only 1,4 tons per day. The forehearth is enclosed and is heated electrically using immersed molybdenum electrodes.
At the other end of the scale the second installation is used to press high voltage electrical insulators, with gob weights of up to 7,5 kg (7500 gram), with temperatures as low as 1050 °C at the front of the forehearth. The forehearth is a conventional gas heated unit.
It is hard to imagine a greater contrast of two production lines, especially of two lines that were commissioned within a few weeks of each other.