Feeding high-concentration coloured glass (glass rod colour raw material) into the pipe-shaped feeder channel provides extremely flexible colour production conditions. Since the colour is added immediately prior to feeding, the glass melting process and the forehearth are unaffected by the colouring process. Colour change times are reduced to a minimum, since the pipe-shaped feeder channel and feeder contain a minimum volume of glass.

The colouring equipment is mounted onto the pipe-shaped feeder-channel, which supplies the feeder with molten glass from the furnace. In the colouring cell, the glass rod is fully automatically fed into the horizontal colourless glass stream. The vertical movement of the glass-rod is performed by a servo-motor system which allows a highly precise and computer-aided control of the feeding speed for the glass rod. This guarantees long-term consistency and reproducibility of the colour intensity for the production process. The infrared radiation of the hot glass stream causes the glass rod to melt before it enters the glass stream, which enhances the colour distribution in the colourless glass. The colour cord is diffused by the laminar glass stream in the channel and passes through one or more stirring cells. The minimal surface of the pipe-shaped channel in combination with a highly efficient heating system provides optimal conditions for a highly efficient stirring process. The stirring plunger in the vertical glass flow of the feeder head further enhances colour homogeneity. Full electronic control of all movement and temperature parameters guarantee consistent glass homogeneity and highly reproducible colours.

The compact structure of the mini-melting system allows the system to be installed onto the feeder channel in order to feed pre-molten concentrated coloured glass into the colourless horizontal glass stream of the pipe-shaped feeder channel. There are two application targets: the pre-melting of coloured glass allows to feed higher colour concentrations into the colourless glass stream or allows to colour higher pull rates of clear glass. Higher concentrations are especially necessary for thinwalled (blown) glass items or for low-weight glass items. For higher pull rates, the mini-melting furnace may also be installed onto standard u-shaped forehearth systems. Feeding liquid coloured glass into the liquid colourless glass stream allows to reduce the total channel or forehearth length and curbs energy consumption drastically.

The mini-melting system is mounted onto the pipe-shaped feeder-channel, which supplies the feeder with molten glass from the furnace. Highly concentrated coloured glass is pre-molten and refined in the mini-melting system. The liquid colour is added to the colourless glass stream through an innovative feed-pipe (�liquid in liquid�-colouring technology). A highly responsive temperature control for the feed-pipe allows to efficiently control the quantity of coloured glass which is added by fully electronically controlling the viscosity/time relation. This guarantees long-term consistency and reproducibility of the colour intensity for the production process. The colour cord is further diffused by the laminar glass flow in the channel and passes through one or more stirring cells. The minimal surface of the pipe-shaped channel in combination with a highly efficient heating system provides optimal conditions for a highly efficient stirring process.