ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17370.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17371.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTReview of literature.—The literature on acid resisting enamels and glasses is reviewed.Acid resisting powers produced by different oxides.—When substituted one for another, in each case in equal percentage amounts, various oxides and minerals increased the resistance of various enamels to the action of boiling 20 per cent hydrochloric acid in the following order of effectiveness: Al2O3, cryolite, Na2O, PbO, BaO, Li2O, MgO, CaF2, ZnO, SrO, CaO, B2O3. The first five mentioned were especially effective. The remainder are undesirable materials from the standpoint of acid resistance.Effect of the enamel base.—The relative effects of the materials were the same for various base enamel compositions.Effect of ZrO2and TiO2.—ZrO2and TiO2, when substituted for small amounts of SiO2, increased the resistance of various enamels to attack by acids, ZrO2being most effective in this respect. The favorable action of ZrO2, is offset by a tendency to produce excessive chipping. Rutile gives less chipping than either zirconia or silica and greater acid resistance than silica.Best compositions.—Enamels 2,17,19,26,27, and 33 of table 1 showed resistance to action of the acid equivalent to that of the original competitions based on the analysis of a French acid‐resisting enamel. By use of the data developed in this investigation other highly acid‐resisting compositions can readily

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17372.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTField covered.—The glazes studied covered the field 3.0 to 13.0 equivalents SiO2and 0.3 to 3.25 equivalents A12O3between the A12O3:SiO2ratios of 1:4 and 1:20. The RO was maintained at 0.7 CaO and 0.3 K2O.Deformation temperatures.—The deformation temperatures were determined by cones in a small gas furnace heated at the rate of 5O°C per hour. The deformation temperatures are shown graphically by isotherms. The results of the part of the field previously covered by Stull and Howat agree with their work. It was found that there is a deformation eutectic axis at a slight inclination to the ordinate representing A12O2up to 7.0 equivalents SiO2. Above 7.0 equivalents the inclination rises, and at 11.0 equivalents SiO2it increases much more.Firing tests.—The glazes were applied to porcelain cups biscuited at cone 08, and fired to cones 10, 12, 14 and 16. The cone 10 test was made only for comparison, since Stull and Howat had previously covered a small part of the field at cones 9 and 11.The glazes are plotted both by empirical formulas and batch weights, showing the location of the best glazes at the different temperatures.In agreement with Stull's statement, increase in Al2O3in this type of glaze decreases crazing.Increase in SiO2will not decrease crazing but if carried far enough will cause crazing to occur.From cone 12 to cone 16 the best glazes have A12O3and SiO2contents corresponding to the approximate formula A12O3= 0.3 + 1/1

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17373.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTTwo terra cotta industries using Ohio clays existed in Ohio prior to 1860. Today no terra cotta industries exist within the State, although Ohio has the clay, fuel and skilled labor. One Ohio clay, the Tionesta or No. 3 B, is especially adapted for terra cotta. It crosses the state through Vinton, Hocking, Perry, Muskingum, Coshocton, Tuscrawas and Stark Counties.The occurrences and chemical composition as determined by the Ohio Geol. Survey are given by the author.This clay burns with a shrinkage of about 6 per cent and a porosity of about 8 per cent from cone 2 to cone 5 with practically no color variation. It will carry its own weight of non‐plastic without serious loss of mechanical strength.Successful combinations and working directions for body, engobe, glaze and vitreous slip are give

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17374.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTBefore installing a Dressler tunnel kiln, Norton Company made a study of an existing kiln. At Steubenville, Ohio, the kiln was found to be working well; repairs were small, economy in fuel, labor and firing time had resulted. The heat distribution was found to be variable but subject to control. The amount of rejected ware was very small and in no case could it be charged definitely to the kiln.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17375.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTA surface combustion furnace lined with alundum and fed by seven burners supplied from a mixture box in which an explosive mix. Of gas and air is made by a special inspirator melts down cone 36 in one hour using 156 cu. Ft. of city gas. The max. temp., 3400°F, attained is within 200°F, of the theoretical max. Advantages claimed are: Simplicity, low fuel consumption, ease of observation and measuring temperatures and ability to produce either neutral, reducing or oxidizing atmospher

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17376.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

摘要:

ABSTRACTLife factors.—The life of fire clay slabs, rings and saggers is influenced by a number of factors, both mechanical and chemical. The chief factors controlling the life of the slabs are (1) proper selections of clays and grog, (2) medium absorption or porosity, (3) strength in the unburned state, (4) proper and thorough blending and preparation of the mix, (5) proper pressing so as to insure freedom from flaws, (6) proper drying, (7) proper setting in the kilns and especially (8) initial burn. These factors are briefly discussed.Setting.—The manner of setting grinding wheels, using large slabs is described. This manner of setting causes transverse bending stress to be set up in the slab and shear stresses to develop. This shearing force, in connection with the large size and the high temperature (cones 11 to 12), make severe conditions for the slab to withstand.Shape and size.—The rate of heating and the size and shape of the slabs are additional factors. Round slabs, up to about 20° in diameter have a decidedly longer life when made in two half sections as compared with the solid shape. Larger slabs have longest life when split up into four sections, while if solid they will fail in one burn. Warping of the slabs, as well as cracking, causes failure. In general, if the width of area of the load is held constant, and length of span of the slab is increased, deformation and cracking is slightly increased. If the span is held constant, and the width or load area is increased warpage is greatly increased, especially as the number of burns under load increases. Cracking also increases in direct proportion to increase in width. These features are more pronounced the longer the span.Ultimate failure at high temperatures.—When not due to structural defects, failure is brought about by a gradual decrease in mechanical strength from burn to burn, so that fire‐clay slabs under transverse load at such temperatures have decided

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17377.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17378.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1921.tb17379.x

出版商:Blackwell Publishing Ltd    

年代:1921

数据来源: WILEY