Glass Tank Furnaces Research Articles

Theoretical Considerations to the Optimum Dimension of Throat of Glass Tank Furnace

The dimension of throat is one of the most important problems concerning the design of tank furnace, because it is on the closest relationship to the acquisition of homogeneity of the glass and the long life of the throat refractory. Nevertheless, as none of the theoretical rules in respect to this problem has been found hitherto, the dimension of throat is determined only by experiences. But the optimum condition of throat with the simple type may be found by theoretical considerations alone.In consequence of the mathematical treatments, the velocity distribution formula of the throat current was derived, and then it was found that the velocity of throat current varies remarkably by the height of the throat and obtains a minimum value at a suitable height and width. Assuming that this dimension is the optimum condition, the following formula which determines the optimum dimension of throat was given.f1/4hopt=2.88(Wηl/ρ0ρbgkΔθ)1/4Moreover, as a result of calculation of the throat current under the optimum condition, it was concluded that the velocity of the current under this condition is almost determined only by the height of throat, but not nearly affected by the corresponding width and the speed of pull. Results of these calculations are in fairly good agreement with the observed and calculated values which were reported already by the other investigators. However, it was concluded that the theoretical value of the optimum height is obviously lower than the practical dimension.

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Flow of Gases in a Glass Tank Furnace, (II)

Flow of Gases in a Glass Tank Furnace, (II)

Model Study of the Current Distribution in the Electric Glass Tank Furnace

Model Study of the Current Distribution in the Electric Glass Tank Furnace

Studies on Glass Tank Furnaces by Model Experiments

Studies on Glass Tank Furnaces by Model Experiments

Refractory blocks for glass tank furnaces. By J. H. Partridge, B. Sc., Ph.D. With a Foreword by Prof. W. E. S. Turner, O.B.E., D.Sc., M.Sc. Pp. x + 128. Sheffield: Society of Glass Technology, 1935. Members 6s. 6d., non‐members 8s. 6d.

Refractory blocks for glass tank furnaces. By J. H. Partridge, B. Sc., Ph.D. With a Foreword by Prof. W. E. S. Turner, O.B.E., D.Sc., M.Sc. Pp. x + 128. Sheffield: Society of Glass Technology, 1935. Members 6s. 6d., non‐members 8s. 6d.

THE INSULATION OF ROOFS OF GLASS FURNACES

It is unjustifiable to assume that a furnace roof cannot be safely insulated. The principal variables controlling the possibility of safe insulation are: (1) temperature of bath below melting point of silica brick roof; (2) transparency of the atmosphere within the furnace, i.e., no possibility of impingement of dense hot flames. The data of this paper are taken from observations on a glass tank furnace in which the combustion rate (B.t.u. per cu. ft. per hr.) is very low. A testing method is described which will show whether or not insulation is safe for any given furnace, considering only the temperature of the inside face of the brick as affected by the application of insulation. The possibility that if the roof is insulated the progress of fluxing of the silica brick by dust and fumes within the furnace may be accelerated because the higher mean temperature of the brick is considered. In the furnace observed, corrosive dust and fumes were in the gases to a considerable extent, yet no unusual deterioration of the roof brick was noted after three years of insulation under continuous operation.

THE HEAT BALANCE OF A GLASS TANK FURNACE1

A seventy-two hour test was carried out on a continuous side-fired regenerative glass tank furnace with five oil burners on each side. A novel feature of this furnace was the insulation of the entire silica brick cap by means of a high temperature insulating brick. A complete record of the furnace operation during this period is given. Temperature measurements were made a t various points in the furnace and regenerator. A feature of the temperature observations is the great magnitude of the radiation correction when hot gases are flowing through passages lined with cooler brick work. The method described by Kreisinger and Barkley was used in making these measurements. This method could be employed for direct reading of true temperature at any point in the regenerative system. The heat balance of the complete furnace system between points at bottom of regenerators is given. Possible savings of fuel amounting to 14% of the total fuel burned are shown. An important fact brought out by this heat balance is that leakage through furnace brickwork is as prolific a source of heat loss as flow of heat through them by conduction.

CHECKER BRICK FOR RESISTING ALKALINE SLAGS1

ABSTRACTChecker brick of varying composition were tested by placing them in the regenerators of two glass tank furnaces. The operation of one furnace was representative of those making the usual grade of bottle glass while the other was operated at a considerably higher temperature and with a more corrosive dust.The amount of corrosion of the checker brick varied directly with the silica content of the brick. Those highest in alumina gave excellent service in the regenerator operating at the lower temperature. In the other regenerator, however, the. dust adhered to the high alumina brick and tended to clog the regenerator while it apparently fluxed and drained off of those higher in silica, leaving free passage for the gases.The brick were tested in the laboratory by making into cones with various percentages of the corrosive dust and determining the fusion point of the cones. The results agree closely with those obtained from the service tests.Detailed results including partial analyses of the brick and flue dust are given.