The Rate of Wear of Tank Blocks in Service

JSGT 1947 V31 T194-T212

The rate of wear of refractories in the sidewalls of tank furnaces melting colourless glass has been measured, at intervals throughout five complete furnace lives. Experimental observations have been made on fusion-cast mullite, on sillimanite, and on fireclay tank blocks, not all of the same original thickness, in furnaces operated at various levels of temperature and melting under different glass loads. Rates of wear have been determined under conditions of natural cooling, and also when high-velocity, forced air cooling was applied. As predicted by W. M. Hampton, an approximately linear relation was found to exist between age of furnace, and the block thickness measured at a point 2" below the glass surface; the wear deviated from the straight-line relation and diminished appreciably when the blocks reached a thickness of 3" or 4". The fusion-cast blocks showed more resistance to wear than the two types of sillimanite. The latter in turn were superior to the fireclay blocks in the service trials made to date. When forced air cooling was applied, the rate of wear appeared to diminish in two observed cases of fusion-cast, and of fireclay refractories, the drop in rate of wear being greater in the case of the fusion cast material. High velocity, forced air cooling exerted a measurable influence through some 10" of fusion-cast block. Studies were made of the influence on rate of wear, of various levels of furnace temperature, of the position of the test blocks within the furnace, and of the porosity of the blocks. Mean thicknesses of sidewall blocks in the melting end at the conclusion of a period covering several furnace lives were quoted.

H. Whittaker & E. Seddon