Controlled Bubbling For Colour Change Efficiency

Many glass container manufacturers will agree that carrying out a colour change can present problems with prolonged glass defects as the old colour is gradually flushed out of the furnace, working end and forehearths. This is particularly an issue when going from a dark composition to a lighter one, and can lead to defects as the colder, darker glass becomes entrained from areas such as the corners of the throat and any areas where there is a transition in depth or direction. In this article the author, Grahame Stuart, or Electroglass, discusses the employment of precision controlled bubbling for colour change efficiency in glass containers.