THE EFFECT OF STEAM ON THE TRANSVERSE STRENGTH OF FIRECLAY BRICKS1

In connection with an investigation of checker brick for carbureters of water-gas machines, it was considered desirable to find out whether or not fireclay brick suffered an appreciable decrease in transverse strength when exposed to the action of steam at a high temperature. Except for occasional references to the “destructive action” of steam, no information on this score was found in the literature. This paper describes experiments in which standard straight bricks at 11,00°C were subjected to the action of steam at the same temperature and the resulting change in transverse strength measured. No significant decrease in strength due to the action of steam alone was found.     

SERVICE FACTORS GOVERNING THE SLAGGING OF BOILERFURNACE REFRACTORIES1

Service factors, dependent on the type of coal burned and the method of burning, that are considered to govern slag erosion directly are: refractories temperatures, furnace gas temperatures, furnace gas compositions, furnace gas velocities, slag composition, and slag quantities. Values determined for part or all of these factors under each of the following sets of conditions are presented and their significance is discussed: eastern bituminous coals on underfeed stokers, powdered eastern bituminous coals in furnaces with extended radiant-heat absorbing surface, high-sulphur Pittsburgh coal on underfeed stokers, low-sulphur Pittsburgh coal on underfeed stokers, high-sulphur Pittsburgh coal on chain-grate stokers, Illinois coal on chain-grate stokers, and powdered Illinois coal.     

STUDIES IN POROSITY AND PERMEABILITY CHARACTERISTICS OF POROUS BODIES1

Definitions are given of porosity, permeability, and weight per unit volume. It is shown that these three terms are not synonymous, and that a change of permeability is not necessarily accompanied by a change in porosity.     

STUDIES OF THE CHANGES IN THE VISCOSITY OF CLAY SLIPS AND GLAZE SUSPENSIONS ON AGING AND BY TREATMENT WITH ELECTROLYTES1

The rate and extent of the spontaneous thinning out of clay slips and glaze suspensions were measured; the effects of electrolytes on the viscosities of slips and glazes after aging until minimum viscosity was reached were investigated; measurements of the rate and extent of the spontaneous thinning of a glaze after treatment with electrolytes were made; and further experiments hearing on spontaneous thinning were conducted, such as heating the slip or glaze and the application of the colorimetric method in determining P_H, etc.     

NOTE ON THE SOLUBILITY OF ENAMEL FRIT IN MILL WATER1

Methods of determining the solubility of enamel frit in mill water are outlined. Various tests tried show that (1) solution increases as fineness increases, (2) mixing has little or no effect upon solubility, (3) variation of smelter treatment has little or no effect upon solubility, and (4) Na₂O and B₂O₃ will dissolve from dry ground frit proportionately to the fineness thereof.