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is reduced with the result that fuel efficiency is lost and good temperature control impossible to maintain. Ceramic burner nozzles from PSR replicate the form and shape of conventional stainless steel burner nozzles, thereby maintaining the seal inside the refractory burner block, but because the thermal conductivity of ceramic is much lower than stainless steel the burner nozzles run hotter, the volatile materials do not condense on the nozzle surface, and the nozzle diameter is maintained. Burner maintenance is eliminated and optimum fuel efficiency and temperature control is continuously maintained for the complete furnace campaign. mr-5000-combustion-systems



Discourage the production of ‘cat-scratch cord’ – How do we do it? PSR is able to provide its cord dispersal stirrer systems for the elimination of cat scratch cord, and to date has supplied almost 200 units. But it is possible to engineer resistance to it at the forehearth and distributor design stage. Although the source is hard to eliminate, being the glassy phase material rich in alumina and zirconia exuded from the fused cast AZS refractories in the furnace melting end, this inhomogeneous glassy material is not only chemically different to the parent glass but more importantly has a different viscosity. So as the glass flow progresses along the distributor and down the forehearths the difference in viscosity between the two glasses will become apparent and the cordy glass will move more slowly and concentrate in colder stagnant areas, waiting to be drawn back into the glass flow as temperature or tonnage increases. If you can ensure good glass thermal homogeneity and eliminate these thermally inhomogeneous areas at the design stage, such as is possible with PSR’s System 500 forehearth, there is a much better chance of discouraging the generation of cat scratch cord. Interestingly, the fact is that most of our Cord Dispersal Stirrer Systems have been installed on competitor’s forehearths rather than on our own. system-5oo

Glass thermal homogeneity – How do we do it? Glass thermal homogeneity for the glass entering the forming operation is traditionally measured by the use of three triplex thermocouples located at the front of the forehearth, although if you were to believe some suppliers’ technical information apparently this parameter is not important. We do not agree. Although good and consistent production efficiency is fundamentally important, glass thermal homogeneity is only unimportant if you are unable to achieve it. PSR’s System 500 forehearth with its hot face forced air cooling and automatically controlled cooling and combustion dampers provides the tools to be able to achieve high glass thermal efficiencies, enabling the glass entering the forming operation to have the tightest possible thermal gradient and the best possible start for today’s lightweight glass container production processes. system-5oo �

*Managing Director, Parkinson-Spencer Refractories, Holmfield, Halifax, UK


The Specialists in Electric Glass Melting and Conditioning BENFLEET, ENGLAND

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Profile for Quartz Business Media

Glass International February 2018  

Glass International February 2018