bluuebunny/crossref_metadata_2025 huggingface dataset:
DISINTEGRATION OF SODA LIME GLASSES IN WATER1
Authors: Williams Arthur E.
Published: June 2006

Soda lime glasses have been treated in water at temperatures helow boiling point, at boiling point, and up to 25 lb. pressure in an autoclave. Effects produced are illustrated with photographs and show that glass disintegrates, i. e., cracks, spalls, and loses weight when treated at any temperature used. The rate of disintegration depends upon time, temperature, composition, and heat treatment of glass surface during forming, the latter factor apparently affecting considerably the tendency to spall or chip.

Treatment given glasses conforms in many ways to treatment glass receives in service, either when sterilized when used for food packing or continued washing and sterilizing as when used for delivering or serving food daily. The relative endurance of glasses may be studied by the methods used, and standard methods of testing based upon them can be worked out. An article must stand at least six hours in boiling water without apparent disintegration or chipping to be of good quality.

Spalling always appeared on the exterior only of pressed or blown ware. Disintegration of the glass is cumulative with time of treatment whether it be periodic or continuous treatment. Treating glass in hot water with increasing pressures does not seem to give greatly increased disintegration as the temperature and pressure rises.

Surfaces of blown or pressed articles are shown to be laminated rather than smooth and impervious.
THE PRODUCTS OF THE CALCINATION OF FLINT AND CHALCEDONY1
Authors: Washburn Edward W. , Navias Louis
Published: June 2006

Outline of the Investigation.—This investigation includes the measurement of the following physical properties; specific gravity at 0°, 25° and 98°, the index of refraction, the coefficients of thermal expansion up to 300°, the inversion temperature and volume change on inversion, and the X‐ray spectra, the materials studied being quartz, tridymite, cristobalite, silica glass and raw and calcined flint and chalcedony.

New Methods—For specific gravity, a special vacuum pycnometer was employed and the immersed powder was later subjected to a pressure of 1000 atmospheres.

Resultss.—The numerical data obtained are summarized in Table I and the X‐ray spectra are shown in Fig. 10. The specific gravity of calcined chalcedony was raised 2% by fine grinding.

Conclusions.—All of the known facts concerning chalcedony are in harmony with the theory that the raw material is colloidal quartz and the calcined material colloidal cristobalite.
THE CONTROL OF BISCUIT LOSSES1
Authors: Sproat Ira E.
Published: June 2006

The effect of the transverse strength and the moisture content of the body on biscuit losses is discussed. A transverse strength of 280 pounds per square inch and minimum moisture content produce the best results.

The analysis of the damaged ware and the brushers report gives data of great value in decreasing the biscuit losses, under given factory conditions.
THE MICROSCOPIC EXAMINATION OF THE MINERAL CONSTITUENTS OF SOME AMERICAN CLAYS1
Authors: Schurecht H. G.
Published: June 2006

The difference in structure of the English and American clay grains and mineral constituents were examined under the microscope.

English kaolin consists chiefly of crystalline Kaolin being similar to North Carolina kaolins in this respect. Georgia, South Carolina and some Pennsylvania clays consist largely of “colloidal” kaolin, which accounts for their difference in physical properties.

The objectionable abrasive features of the American clays causing excessive wear to machinery can be readily overcome by more “refined” refining methods but it is impossible by any present known methods or process to transform the colloidal kaolinite particles of our transported clays into the crystalline plate‐like structure of the English china clay.

Our only hope therefore, of producing clays in this country which will be as satisfactory as those now imported, lies in the development of the crystalline kaolins. This is possible by better mining, blending and refining processes. However, the total tonnage of clay in our crystalline kaolin deposits is limited and if drawn upon intensively they would soon be exhausted.

Minerals found present in the clays are chiefly muscovite, quartz, tourmaline, biotite, zircon, alkali feldspar, plagioclase, rutile, hydrated silica and hematite.
THE DEGREE TO WHICH DIFFERENT GLAZE COMPOSITIONS TAKE VAPOR LUSTERS1
Authors: Watkins R. T.
Published: June 2006

Glazes having an oxygen ratio of approximately 3 to 1, a medium or low acid content with a B2O2 to SiO2 ratio of approximately 1 to 2.5 and high in lead and low in lime, take the best vapor luster effects.
OPERATION OF LEERS1
Authors: Frazier C. E.
Published: June 2006

The muffle and open types of leers are compared. The latter has the following advantages: (1) More uniform temps. in the annealing chamber; (2) prevents ingress of cold air beside pans and thus avoids consequent cracking of the ware; (3) better control of temp. and greater reliability of pyrometric indications; (4) less fuel per gross of ware.

Size of leers: Leers 8 ft. wide and 65 ft. from center to center of sprockets are recommended for the average glass.

Leer chains: Chains having a working strain of 5800 Ibs. at 200 ft. per minute are recommended.

In the discussion, L. H. Adams points out that the exact annealing schedule required for any glass can be computed from the annealing constants of the glass which are known or can be determined in the laboratory.
THE COST SYSTEM AS AN AID TO EFFICIENT PLANT CONTROL1
Authors: Farnham Dwight T.
Published: June 2006

A cost system for a clay plant is described, by means of which complete records are kept of the condition of the plant each day as compared with an established standard. The results of such a system are a more perfect understanding between superintendent and general manager as to the actual factory conditions and increased efficiency in plant control. Graphic charts keep the information before the executives and workmen alike, thus leaving no one in ignorance of the progress of the work as compared with the established standard.
POROSITY: V. RECOMMENDED PROCEDURES FOR DETERMINING POROSITY BY METHODS OF ABSORPTION
Authors: Washburn Edward W. , Bunting Elmer N.
Published: June 2006

Detailed Procedure.—For shaped test pieces details of the procedure are given under the headings. “Preparation of Test Piece.”“Determination of Dry Weight,”“The Absorption Apparatus,”“Preparation of Standard Vaseline,”“Saturation Procedure,”“Calculation,” and “True Density.”

A Pycnometer Method.—A new and accurate method, which is applicable equally to shaped test pieces or to granular material, is described. Among other advantages it gives the operator control over the max. size opening which he desires to class as part of the pore space. It also can be made to indicate directly the necessary soaking period.
THE INFLUENCE OF HEAT ON THE MICROSCOPIC PROPERTIES OF SILICA IN ITS DIFFERENT MINERAL FORMS1
Authors: Robson J. T.
Published: June 2006

A study is made of the effect of heat at cone 13 and cone 14 on the index of refraction of the four common mineral forms of silica used in the ceramic industries. These mineral forms are sand, quartz, chalcedony and French flit. The effect of these mineral forms on the index of refraction of porcelain bodies fired to cone 13 and cone 14 is also given.
REFRACTORY CLAYS OF ILLINOIS1
Authors: Parmelee C. W.
Published: June 2006

A brief discussion of the geological occurrence of the fire‐clay beds in Illinois and the results of testing samples which are typical of various areas.
DATA ON VISCOSITY OF INDIANA CLAY SLIP WITH ELECTROLYTES IN REGARD TO THE CASTING OF TERRA COTTA1
Authors: Davis H. E.
Published: June 2006

A presentation of data on the use of several electrolytes with one particular clay, to wit: Indiana clay, such as is used by the terra cotta manufacturers of the Chicago district.

The various electrolytes used were sodium carbonate, sodium silicate, the two combined half and half, gallic acid, and tannic acid. Data was obtained by determining relative viscosities with the use of a flow viscosimeter, and by measuring the thickness of wall cast in a given time.

Sodium carbonate, used alone, seemed to be the most satisfactory. Tannic acid shows possibilities, but so much is required as to be commercially impractical.
AN OIL‐FIRED FURNACE FOR THE PLANT LABORATORY
Authors: Moulton D. A.
Published: June 2006

Description of Furnace.—This is an iron‐encased furnace with 1½‐inch asbestos insulation. The chamber is 21 inches square by 20 inches high and will hold 14 bricks on end.

Operation of Furnace.—This requires from 16 to 20 gallons of fuel oil per heat of high temperature for a period of five hours. Pre‐heated air is supplied by a No. 4 Blower running 3000 R.P.M. delivered through a 3‐inch pipe.
TERRA COTTA PROBLEMS SUGGESTED FOR DISCUSSION AND INVESTIGATION1
Authors: Hill C. W.
Published: June 2006

An occasional review of the manufacturing problems of any industry regarding which positive information is fragmentary or lacking is often of value. Such a review of some of our terra cotta problems may be productive of discussion which will bring to light unpublished data and may inspire our industrial ceramists to increased activity in fundamental research. It may also be of value to our University friends who are frequently in search of research problems of a practical nature. Naturally any summary prepared by an individual will not be complete but the omission of points which others regard as important will usually be noted and supplied by discussion.

The following subjects are proposed for discussion and investigation:

Plaster

Materials: (a) Body mix and materials, (b) barytes, (c) grog

Glaze

Process

Patching

Service problems.
INVESTIGATION OF DUST PRESS PRACTICE AS INFLUENCING FINISHED SIZES AND CRACKING
Authors: Spurrier H.
Published: June 2006

Owing to erratic firing behavior, the factors affecting finished sizes of ware were investigated. Uneven distribution of air and water content and uneven density produced irregular shrinkage and consequent cracking and warping. The percentage of water in the clay as pressed is shown to be the dominant factor as affecting shrinkage.

Suitable loading of die corrected the differential shrinkage.

Experimental procedure is detailed. Influence of rate of pressing on porosity is set forth.
THE EFFECT OF SOURCES OF PIG IRON UPON THE ENAMELING OF CAST IRON
Authors: Manson M. E.
Published: June 2006

Cast iron made from certain “northern” pig iron blistered badly, while that made under the same conditions from “southern” pig iron enameled satisfactorily.

The use of “northern” iron results in castings with low content of combined carbon although the other constituents usually determined in cast iron were present in about the same quantities as found in cast iron made from “southern” pig iron.

Reducing the silicon in the iron made with the “northern” pig iron from 2.80 to 2.30% with a total carbon content of 3.30%, resulted in the elimination of blistering in the enameling operations. Experiments have indicated that cast iron of this type with combined carbon less than 0.15% will develop blistering. However, it has not been definitely determined as yet whether the blistering is due directly to this low carbon content or to the presence of some other constituent not generally determined in a chemical analysis of cast iron.

Micrographs are shown of various irons before and after enameling. While these show some differences, it has been impossible to detect the cause for the blistering by means of them. All blistering irons, however, show in the micrographs characteristic dark blotches which have not as yet been identified.
GLASS CONTAINERS1
Authors: Bitting A. W.
Published: June 2006

For centuries glass bottles have been recognized as superior containers. At present over 4000 different sizes and shapes are being made and the industry is in a state of rapid extension. Glass containers possess the advantage of being sanitary and permitting the contents to be seen. Recently the laboratory of the Glass Container Association has tested 180 lots of beverage bottles. Some of the better types, or those approaching the champagne style, were found to withstand an end crushing pressure of from 8000 to 12000 pounds, a transverse pressure of from 800 to 1800 pounds, a hydrostatic pressure of from 400 to 1600 pounds, and an impact of a fifty‐pound hammer falling from 2 to 6 feet. Similar tests are in progress on other types of containers and on the closures employed. Troubles due to alkalinity are of rare occurrence.
EFFECT OF WEATHER UPON THE STRENGTH OF REFRACTORY BRICK1
Authors: Howe R. M. , Phelps S. M. , Ferguson R. F.
Published: June 2006

Magnesia and silica brick should be protected from the action of the weather.

Open textured fireclay brick (usually having end cold crushing strengths of less than 1500 pounds per square inch) should be afforded protection from the action of the weather.

Finely ground, dense, hard‐burned firebrick, especially those of medium or low refractoriness. may be exposed to the action of weather with a reasonable amount of safety. These are usually made from one clay which is shaped on a dry press or auger machine and have an end cold crushing strength approximating 5000 pounds per square inch.
A DEVICE FOR TESTING THE RESISTANCE OF CHINA TO CHIPPING1
Authors: Schramm Edward
Published: June 2006

The device (shown in the figure) measures the blow required to chip the edge. Results are reproducible to within about 10%, this variation being due to lack of uniformity in the pieces tested. Vitrified china is more resistant to chipping than is semi‐porcelain or European true porcelain.
A SMALL GLASS TANK1
Authors: Bsllamy H. T.
Published: June 2006

The construction of the furnace is shown in the figure. It is fed from the 3 burners and uses about 24,000 cu. ft. of B.t.u. gas per 24 hours. It successfully melts high lead crystal, alabaster, opal, gold ruby opalescent, and green opalescent glasses.
THE RELATION OF FINENESS OF GRINDING TO OPACITY IN WHITE ENAMELS
Authors: Sweely B. T. , Prince E. S.
Published: June 2006

The problem of securing a uniform opacity by making observations of smelting, testing of raw materials, etc., led to the conclusion that the most important process was the mill treatment given the mixture. A table showing screen analyses of white enamels is given.
COMPARATIVE TESTS OF ENGLISH AND DOMESTIC WHITINGS1
Authors: Williams A. E. , Woods B. J.
Published: June 2006

A knowledge of the properties of American whiting as compared with those imported from England is of importance to producers of the American material as well as to manufacturers of products in which whiting may be used.

Twenty‐two samples of domestic and foreign whiting have been submitted to examination and tested as follows: (1) visual examination, (2) microscopic examination, (3) determination of fineness of grain by three methods, (4) partial chemical analysis, (5) effect of the different whitings on the softening point of ceramic cone mixtures, and (6) effect on rate of vitrification of porcelain bodies.

The results indicate that although the English whitings contain considerably more fine material of a colloidal nature, the American whitings appear to be sufficiently fine grained for all ceramic purposes.

This extreme fineness may play a part in assisting in the flotation of the frit in glazes containing a low percentage of clay, but apparently has no effect in the fluxing point of ceramic glaze or body mixtures.

Sufficient data has been obtained to permit of the preparation of tentative specifications for whiting for ceramic purposes and the main requirements of such a material are given.
THE MECHANICAL MOVEMENT OF WATER THROUGH CERTAIN CLAYS AND ITS CONTROL12
Authors: Schurecht H. G.
Published: June 2006

Introduction.—Ceramic bodies containing Georgia clay cast and release from the molds slower and have a greater tendency to crack in drying and burning than similar bodies containing English china clay. Experiments were conducted to improve these properties of Georgia clays by studying the movement of water through them and its control.

Permeability.—It was found that the permeability of the clays to water was independent of the time between 2 and 10 days; that is, P is nearly constant in the formula P = W/T, in which W is the total water which has passed through and T is the time in days. This factor for North Carolina kaolin was 1.55≠.05; for English china clay 1.45≠.06; for Georgia clay 0.938≠.07; for South Carolina clay 0.673≠.07; and for Tennessee ball clay 0.64≠.08.

Capillarity.—The investigation showed that the capillary rise of water through these clays may be expressed by the formula H=Ch (log T ‐ 1.041) in which H is the height attained by the water in time T, and Ch is approximately constant for each clay between 10 and 250 minutes, that is, it represents the movement of water through clay when it contains a certain amount of water below that required for saturation. This factor for North Carolina kaolin is 6.67≠ 0.30; for English china clay 7.30≠ 0.70; and for Georgia clay 4.66≠ 0.80. The great capillary conductivity of water through primary kaolins explains why bodies containing these get drier and release from the molds quicker than those containing secondary clays.

Methods for Improving Georgia Clay.—The Permeability factor of Tennessee ball clay was increased from 0.64 to 1.20 by adding 0.7% NaOH, and that of kaolin from Dry Branch, Georgia increased from 0.938 to 1.72 by calcining to 450°C. By either, or a combination of the above treatments, it was possible to improve the properties of many Georgia clays, making them more like the English china clay in regard to permeability to water.
USE OF OX GALL IN PREVENTION OF CRAWLING OF GLAZES
Authors: Spurrier H.
Published: June 2006

The crawling of glazes may be entirely prevented by the use of ox gall in solution. The action is probably due to the lessened surface tension.
THE WITCHERY OF GLAZES1
Authors: Cox Paul E.
Published: June 2006

A paper showing the extent of research possible in glazes and the fascination of the work in that field. It is implied that the general chemist has little to offer to shorten the road that must be followed and that the work is reward enough for the labor involved. It is shown that the artistic temperament functions in this work along with the scientific temperament.
FURTHER STUDIES OF PORCELAIN GLAZES MATURING AT HIGH TEMPERATURES1
Authors: Twells Robert
Published: June 2006

The investigation covers three fields of glazes: Series A contains 21 glazes with variations in composition as shown in the formula .

Series B contains 10 glazes, each having the formula but having their clay content varying triaxially between Florida kaolin, North Carolina kaolin, and Kentucky ball clay No. 4. Series C contains 20 glazes with variations in composition as shown in the formula .

The method of experimentation consists of grinding the corner glazes of each series wet, for 18 hours, cross blending the corner glazes to produce the intermediate glazes, applying the glazes by dipping to green porcelain discs, and firing them in commercial periodic and tunnel kilns to temperatures between cone 16½ and cone 19 flat. The glazes were examined with the naked eye and a 10 X pocket lens.

The triaxial replacement of CaO by MgO and BaO, as tested, makes practically no change in the appearance of the glazes. With the pocket lens the bubbles in the glazes appear smaller and more numerous, near the BaO apex.

When fired in the periodic kilns for 42 hours the transparency of all the glazes in‐ creases with the temperature. The glazes fired in the tunnel kiln to cone 19 flat in 31 hours are more opaque and smoother than in the periodic kiln at three cones lower temperature.

The triaxial replacement of the Florida kaolin, by North Carolina kaolin and Kentucky ball clay No. 4 produces relatively little change in the fired appearance. The glazes containing all ball clay or a mixture of ball clay and North Carolina kaolin overfire at a lower temperature than do those containing all kaolin or a mixture of Florida kaolin and ball clay.

The best glazes with 0.2 K2O and 0.8 CaO have approximately an alumina: silica ratio of 1:9 and 1:11 for the field covered. These glazes are generally more trans‐ parent than the glazes with 0.3 K2O; otherwise the results are similar.

The conclusions are: (1) that the nature of the firing conditions are of the utmost importance in the development of a glaze, and (2) that an intelligent choice between glazes of equally desirable appearance requires a resort to petrographic method and mechanical tests.
NOTE ON THE HEAT DISTRIBUTION IN UPDRAFT KILNS1
Authors: Bleinincer A. V.
Published: June 2006

In the pottery updraft kiln the rising gas currents tend to separate into distinct streams which follow the lines of least resistance in making their exit through the kiln crown. The draft while weak at first becomes very strong during the heat raising period and emphasizes the vertical stratification of the gases. In using natural gas as fuel complete combustion is not usually attained during the period of maximum firing and CO is invariably found present.

The irregularity of the heat distribution is chiefly due to the formation of distinct gas currents and the long soaking of the top in order to secure proper heating of the bottom. Remedies proposed are slower raising of the heat in order to secure top and bottom temperatures more nearly equal and reducing the time of the soaking period which is often excessive; the use of dampers for the control of the draft; and the employment of low pressure forced draft. It is believed that in the future the application of positive pressure will prove most effective in securing more economical firing in all types of periodic kilns.
EFFECT OF VARIOUS SIZES OF GROG PARTICLES ON CLAY POTS
Authors: Williams Warren S.
Published: June 2006

The service obtained from refractory clay, glass‐drawing pots, 40 inches in diameter, was increased in factory practice by eliminating grog particles finer than 40‐mesh.
AN INVESTIGATION CONCERNING THE INFLUENCE OF THE ALKALIES AND ALKALINE EARTHS ON THE FUSION TEMPERATURES OF THE DIFFERENT TYPES OF REFRACTORY CLAYS
Authors: Watts A. S.
Published: June 2006

A summary of results of an investigation regarding the application of Richter's law and its modifications to refractory clays of higher and lower alumina and silica content than previously studied.
REFRACTORY REQUIREMENTS FOR OIL REFINING
Authors: Wikoff Alan G.
Published: June 2006

Aside from boiler settings and such minor uses as fullers earth revivifying furnaces and sludge acid recovery plants, the main use for refractories in oil refineries is in fire still settings. With the shell type stills which were almost exclusively used in the past, service conditions are not severe enough to require anything more refractory than the best quality No. 1 fire brick, but some of the tube type cracking stills recently introduced are much more severe in their refractory requirements.
METALLURGICAL REQUIREMENTS OF REFRACTORIES IN COPPER SMELTING AND REFINING1
Authors: Pyne Francis R.
Published: June 2006

The requirements of refractories in the copper industry may be classed as follows:

Resistance to temperatures

Resistance to chemical action

Ability to withstand sudden temperature changes

Minimum absorption of slag and metal

Absence of manufacturing defects.
THE USE OF WOOD IN GAS PRODUCERS
Authors: Saxton C.
Published: June 2006

The possibility of using wood as source of gas supply for melting of glass and firing of clay products is suggested. Comparative results actually obtained with same plant using coal and wood are given.
THE BEHAVIOR OF FIRE BRICK IN MALLEABLE‐IRON FURNACE BUNGS1
Authors: Scaurbcrt H. G. , Douda H. W.
Published: June 2006

Purpose.—An investigation was conducted to study the requirements of fire clay and bodies used for fire brick in malleable‐iron furnace bungs. Tests were made on complete bungs holding forty sample brick in malleable‐iron furnace bungs with twenty different fire brick. Laboratory tests were also made in conjunction with them.

Results.—The spalling tests bear the closest relation to the service test; those brick losing less than 10% withstand more than fifteen heats.

There is also a relation between the porosities and densities of fire brick, which lie between 15 and 28% and 1.5 and 2.6%, respectively, for the best brick.

There is no close relation between the load test and softening‐points of fire brick and their lifetime in malleable furnace bungs, so these tests are no criterions in judging the serviceability of brick, provided the brick are sufficiently refractory to support the arch at furnace temperatures.

Methods for Improving Fire Brick.—The resistance of a brick to spalling may be governed by: (1) the selection of the proper clays, (2) the size of grain and the proportioning of the non‐plastic ingredients, (3) the fineness of grain of the bond clay, (4) the manner of molding, and (5) the temperature of firing.
METHOD FOR ANALYZING DIASPORE CLAY
Authors: Thornbbrry M. H.
Published: June 2006

The method of analyzing refractories recommended by the A. S. T. M. having proved unsatisfactory for diaspore clays, a change has been made whereby fusion is accomplished by adding c. p. NaOH instead of Na2CO3 to the finely ground clay and the mixture heated in a nickel crucible over a bunsen burner.
THE EFFECT OF HEAT‐TREATMENT AND COMPOSITION OF SEMI‐PORCELAIN BODIES ON CRAZING
Authors: Sproat Ira E.
Published: June 2006

Limits of Investigation.—The investigation was confined to practical semi‐porcelain bodies and glazes, therefore, the results may be applicable only to this branch of the whitewares industry.

Effect of Thickness of Glaze.—The thicker the glaze the greater the tendency to craze. The glaze on several pieces of dinner ware may appear to the eye to be of uniform thickness, but still have sufficient variation in thickness as to show difference in crazing behavior. It being impossible to obtain a uniform thickness of glaze by hand dipping there is a need for a mechanical dipper. An improved type of biscuit kiln which will produce ware with a uniform absorption is another need.

Effect of Glaze Composition.—When sufficient change was made in the composition of a typical semi‐porcelain glaze to cause a marked decrease in its crazing tendency, it was at the expense of other desirable properties.

Effect of Body Composition.—The addition of 10.0% to 20.0% of “Hercules” clay to a general ware body greatly decreased its tendency to craze. No other change in body composition was found feasible, for when the change was sufficient to cause a decrease in the crazing it was at the sacrifice of other essential properties.

Effect of Variation in Absorption.—Contrary to the general opinion among potters, the tendency to craze was not increased by every increase in absorption. An absorption of about 7.0% to 12.0% showed the most resistance to crazing.

Effect of the Time‐temperature of the Gloss Burn.—Tendency to craze is decreased by increasing the maturing time‐temperature portion of the gloss burn.
DEFORMATION STUDIES OF SILICATES AND ALUMINUM SILICATES OF THE ALKALIES
Authors: Rice Bryan A.
Published: June 2006

The following investigation includes studies of the two ternary systems K2O2‐Al2O3‐SiO2 and Na2O‐Al2O2‐SiO2.

In each system two areas of low fusibility were found; one including members high in alkali, low in silica, and low in alumina; the other including those high in silica, low in alkali, and low in alumina. In both systems the high silica area was the one studied in detail as being of more practical ceramic value.

On each triaxial three eutectics (two binary and one ternary) were established. They had the following compositions:

The terms “eutectic” and “deformation eutectic” are used in this paper to designate those compositions which require the lowest temperature to complete deformation when uniformly heated with other compositions in the manner outlined in the following studies. Deformation was judged by the same method used with standard pyrometric cones.
THE VALUE OF SCREEN ANALYSIS IN CERAMICS
Authors: Nickerson F. P.
Published: June 2006

The development of equipment for classifying materials according to size. The importance of classification and proportioning of size of particles in products made from ground or crushed material.

The advantages in screen analysis, of testing sieves with openings made to a fixed ratio.

The advantages of logarithmic or direct diagram plotting of screen analysis.

Checking the efficiency and controlling the character of the product obtained from grinding units and checking products whose value is influenced by the size of grain.
SIMPLE METHOD OF MEASURING COLOR
Authors: MUNSELL A. E. O.
Published: June 2006

Clear thinking on color is important. The Munsell System clarifies; shows color in three dimensions: hue, value, chroma. The method of measuring color on solid, sphere, irregular solid, vertical and horizontal slices through the solid. Method of notation. Summary.
SHOP NOTES—PLASTER SHOP
Authors: Klinefelter T. A. , Parsons F. C.
Published: June 2006

This paper deals with the small problems which arise in the plaster shop, and are a source of annoyance and cost if handled incorrectly. The grade of plasters used, manner of handling, method of payment, extent of reinforcement of molds, care of benches, correct procedure in making the various parts and types of molds, are all touched on.
SHORT CUTS IN MITRE CUTTING
Authors: Klinefelter T. A. , Parsons F. C.
Published: June 2006

A discussion of the proper type of man to develop for mitre cutting, with hints as to quick and easy ways of doing the various processes involved in cutting and sticking mitres.
THE USE OF BENTONITE FOR SUSPENDING ENAMELS1
Authors: Manson M. E.
Published: June 2006

Bentonite, a highly colloidal clay, has a much greater suspending power than the ordinary enameling clays. One part of bentonite is equivalent to five parts of clay. Its use enables the enameler to reduce the amount of raw materials necessary to add to his frit. Some disadvantages are pointed out.
PRODUCER GAS FOR BURNING REFRACTORIES1
Authors: Richardson W. D.
Published: June 2006

History of installations in the United States of producer gas for burning fire brick. Causes of failure or abandonment of producer gas firing. Continuous regenerative kiln necessary for successful burning at high temperatures with producer gas.

The compartment kiln, fired with producer gas, best adapted for general refractories. Advantages of the compartment kiln over the car tunnel kiln. Essential features of continuous kilns for the successful burning of refractories. Special features of gas producers for ceramic kilns.

Temperatures from producer gas. Economy of producer gas as compared with natural gas, oil and powdered coal. Investigation of designs and methods of operating gas producers.
COLD CLEAN ARTIFICIAL GAS AND A DISCUSSION UPON THE GENERAL PROPERTIES OF GASEOUS FUELS1
Authors: Blake Alfred B.
Published: June 2006

This paper2 is written for the benefit of glass house people whose training has included no particular study of gas as a fuel. The ad vocation of some departure from the common practice, in the light of good and sufficient reasons, ought to be met in a receptive attitude. Warnings are given as to the acceptance of non‐standard processes, and apparatus proposed by those of precarious financial backing and questionable familiarity with the technicalities of gas supply and application.

There is a brief survey of the field to be covered, followed by a discussion which shows how various gases may be classified. There is a pronounced difference in quality between the various kinds of producer gas, and other standard gases. The heat content per unit volume of theoretically perfect air‐gas mixture is shown to be approximately equal for all high grade gases. This value plus the reaction temperature form two important considerations in the comparison of gas fuels. The importance of high “thermal head” in relation to rapid heating, and the economies of rapid heat transfer are pointed out. The fitness of high grade gas fuel for attainment of highest efficiency is shown. Theoretical flue gas heat losses are given.

A standard of 1.000.000 B.t.u. is proposed as a conversational basis for approximate comparison of gases as regards cost and volumes required. The merits of regeneration or recuperation are obvious for large scale, high temperature heating, but there are many reasons for adopting direct fire heating units for small operations. This emphasizes the value of high grade clean gas. The use of muffles in leers when clean sulphur‐free gas is the fuel is ridiculous.

The cost of a method forms the general determining factor in selection when results to be gained are equal. Technical schools ought to give more training on the subjects of fuels and combustion. Apparatus, methods, materials, yields, properties, and application of coal gas, water gas, mixed coal and water gas, and coke producer gas to the glass industry are discussed briefly and illustrations are given. A table of comparison of these gases is given and is followed by the demonstration of the method of obtaining the results given.
CLAY SEWER PIPE MANUFACTURE
Authors: SCHURECHT H. G.
Published: June 2006

Purpose.—A study was made of the heat distribution in four sewer pipe kilns in order to determine means of making this as uniform as possible and thus produce pipe of uniform maximum strength and reduce the cost of firing.

Results.—It was found that the coolest portions of the kilns are along the entire bottom and on the top near the outside of the kiln. The hottest portion is usually on the top in center of the kiln. Kilns having a small diameter have a more uniform distribution of heat than those having larger diameters.
EFFECT OF TIME AND TEMPERATURE UPON THE CHLORINATION OF FLINT FIRE CLAY
Authors: Kriege Herbert F.
Published: June 2006

An experiment is described in which flint fire clays were chlorinated at fixed temperature between 500°C and 950°C and for varying periods of times. A replaceable condensing system permitted the rate of formation of the volatile chlorides to be studied.
SOM. CAUSES OF BLISTERING OF SHEET STEEL METAL ENAMELS1
Authors: Comstock George F.
Published: June 2006

This paper gives the results of a metallographic investigation of some samples of defective white enameled ware, the peculiarities of the steel underlying the defects having been examined through the microscope. Two distinct kinds of defects were recognized, one of which, characterized by dark spots arranged in streaks, was found to be due to foreign inclusions in the steel. It was concluded that the other defect, consisting of irregularly scattered spots, was most probably due to gas absorption during pickling, the ultimate cause lying either with the pickling process or the steel quality. Detailed descriptions and photomicrographs are given of the structures and inclusions in the steel bases of the samples examined.
SILICA CEMENT1
Authors: McGee E. N.
Published: June 2006

Composition, requirements and specifications for first quality silica cement are discussed. Adequate control tests for determining its suitability are described, together with such investigations as have been made for the purpose of obtaining a satisfactory cement.

The latter part of the paper deals with the bonding qualities. An investigation showed that the use of molasses greatly improved the bond without affecting the refractoriness.
THE EFFECT OF VARIATION IN FIRING ON THE PHYSICAL PROPERTIES OF VITREOUS CHINA BODIES1
Authors: Sortwell H. H.
Published: June 2006

The porosity, transverse strength, compressive strength and impact strength of ten commercial china bodies were determined on sets of specimens fired in three positions in a kiln in each of ten potteries. The results showed that while there was considerable difference in the maximum strength of the bodies, nearly all of them developed high strength when fired most advantageously. The maximum strength existed over a narrower range in heat treatment than that of complete vitrification. Underfiring and overfiring of this type of body caused serious loss in strength.

Specimens of eleven bodies fired at cones 6, 8, 10, 12 and 14 in a laboratory kiln showed about the same differences in maximum strength as specimens of the same bodies fired in the pottery kilns. In one body only was as high strength. developed in the small kiln as in the factory. In most instances the highest strength developed was coincident with complete vitrification and in all the bodies it occurred near or prior to cone 12. There was considerable difference in the range in temperature over which the different bodies were vitrified and were of high strength. While two of the bodies were excellent in this respect, the remainder were vitrified and of high strength through only a narrow temperature range.
THE PROPERTIES OF SOME CLAY‐LIKE MATERIALS OF THE BENTONITE TYPE1
Authors: Schurecht H. G. , Douda H. W.
Published: June 2006

The evidence obtained in this work would indicate that bentonites are mixtures of two or more materials rather than one. The exact composition of these is not known but they are probably mixtures of colloidal silicates and fine‐grained kaolinite in varying proportions.

They are characterized by the following properties: Conchoidal fracture; an index of refraction between 1.48 and 1.54; high water of plasticity and volume drying, shrinkage varying from that of highly plastic clays to 114.61% and 195.9%, respectively; and a high alkali plus alkali earth content, usually above 5%. When added in small amounts to certain clays, some bentonites increase the dry strength to a remarkable extent. In firing they vitrify between 1000°C, soften at cones 1–14 and burn to a buff to brown color and therefore can only be used in small amounts in white ware.

It is possible by adding finely ground quartz and small amounts of bentonite to certain fire clays to produce mixtures approaching the Arkansas and certain other glass pot clays in physical properties and in index of refraction. Adding too much bentonite to clays causes them to crack in drying.
COPPER REDS FOR THE AMATEUR
Authors: Cox Paul E.
Published: June 2006

A brief review of the history of the production of such wares is given. Methods are described that can be used by the person having china painter's kiln. This paper is presented to encourage the amateur to make use of simple equipment for the production of decorated wares in which a satisfactory ceramic red can be produced.
ZIRCONIA REFRACTORIES
Authors: Sheppard Mark
Published: June 2006

Outline of physical properties of zirconium ore.

Mention of zirconia laboratory ware and method of manufacture.

Manufacture and physical properties of zirconia brick.

Zirconia cement and its uses.
FIRING REFRACTORY BRICK IN A ROUND DOWN‐DRAFT KILN WITH A MECHANICAL STOKER1
Authors: Ayars E. E.
Published: June 2006

An outline of firing tests conducted on round down‐draft kilns to develop a mechanical stoker for use in firing fire brick and other refractories. Stoker used has been applied to terra cotta kilns with considerable success but it appears that the larger sizes of kilns are not easily handled with this type of stoker. Further tests may develop something in the way of technique which will show a reduction in firing time. Fuel consumption has already been reduced and uniformly fired ware secured. The time element is of great importance in plant capacity.
FACTORS AFFECTING THE RESISTANCE OF SILICA REFRACTORIES TO ABRASION1
Authors: Harvey Fred A. , Mcgss Earlb N.
Published: June 2006

The resistance to abrasion is tested by grinding a groove in the surface of the refractory by means of a carborundum wheel with suitable mounting. Other methods used in the tests are discussed. Factors affecting resistance of silica brick to abrasion are porosity and degree of burn. Porosity is affected by grind, quality of ganister, per cent lime and workmanship. Data are given showing a rough relation between length of groove, porosity and burn.
THE DEHYDRATION TEMPERATURE OF PYROPHYLLITE AND SERICITE1
Authors: Stuckey J. L.
Published: June 2006

Pyrophyllite and sericite are sometimes closely associated in works and the clays derived from them. They contain similar amounts of chemically combined water, but the sericite gives up its water more readily than the pyrophyllite, and is completely dehydrated at a lower temperature.
AN ADIABATIC METHOD FOR STUDYING SPONTANEOUS HEATING OF COAL1
Authors: Davis J. D. , Byrne J. F.
Published: June 2006

An adiabatic calorimeter is described, by means of which the spontaneous heating characteristics of dry pulverized coal can be studied, so as to obtain a direct measure of the rate of spontaneous heating at different temperatures, uninfluenced by various heat interchange factors. Specimen time‐temperature curves of different coals are presented, which show approximately the same rate of heating over corresponding temperature ranges. From these curves, it is concluded that the main characteristic of spontaneous heating is that the rate of heating is an increasing function of the temperature. An empirical formula is developed, for which the constants, K, a and b, are determined for a Pittsburgh coal; θ= temperature, and T= time. From this formula, it is concluded: (1) no heating will take place below 26.27°C; (2) the time required for Pittsburgh coal to heat from this temperature to ignition is 144 hours, both the coal and the oxygen used being moisture free.
COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1
Authors: Budnikoff P. P.
Published: June 2006

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO3 and determination of CaO by KMnO4 titration, the SO3 by Andrews method of titration of BaCrO4 has been found to give very reliable results with the least consumption of time.
ARTIFICIAL SILLIMANITE AS A REFRACTORY1
Authors: Wilson Hewitt , Sims Clarence E. , Schroeder Frederic w.
Published: June 2006

Alumina‐silica mixtures were prepared by fusing quartz, china clay, fire clay, and alumina in the electric furnace. When alumina is less than 68%, crystalline sillimanite (3Al2O3.2SiO2) with glass is produced. This material is not very resistant to loads at high temperatures because of the early fusion and internal lubricating action of the glass surrounding the crystals. Above 68% alumina, crystalline corundum appears am1 the glass is practically absent. This latter composition is very resistant to high‐temperature loads when ail interlocking, recrystallized bond is developed. This material is not affected materially by acid slags, but it cannot resist basic slags. However, the dense structure of a brick of material above 68% Al2O3 causes less slagging in a laboratory bath test than silica brick. The laboratory made sillimanite‐corundum brick withstood higher temperatures than the best silica, magnesia, chrome, fire clay, or zirconia brick even though the cone of fusion of the former is less than that of MgO, Cr2O3 or ZrO2. More and better service tests with a large number of brick fired in large kilns is needed to follow up this laboratory work.
DEVITRIFICATION IN A LIME‐FLINT GLASS TANK1
Authors: Payne A. R.
Published: June 2006

A brief account of the formation of cristobalite in a tank of soda‐lime glass due to failure of the refractories in the bridge‐wall. The efforts made to eliminate this devitrified glass are described. These efforts were not successful and the only solution was to shut the tank down and rebuild it.
OBSERVATIONS ON THE PROPERTIES OF CLAYS AND CLAY‐GROG BODIES
Authors: Schramm Edward
Published: June 2006

Determinations of shrinkage, absorption, and transverse strength were made on a series of clays and clay‐grog bodies fired together. Highly porous grog bodies are obtained with tight burning clays when the latter possess high shrinkage. This is due to the formation of crevices between the clay and grog particles, and to produce a tight grog body the clay must be of low shrinkage and low porosity.
THE ELECTRIC BRASS FURNACE REFRACTORY SITUATION1
Authors: Gillett H. w. , Mack E. L.
Published: June 2006

The three prominent types of electric brass furnaces are described, and the conditions which they impose on the refractories are outlined. The limitations which the properties of refractories place on the applicability of the various furnaces are considered and an attempt made to point out lines along which development and improvement are most likely to take place.
THE USE OF BORIC OXIDE IN GLASS‐MAKING
Authors: TURNER W. E. S.
Published: June 2006

Boric oxide behaves differently from other glass‐making constituents in that the variation of physical properties is not progressively continuous with a variation in composition. With increase of boric oxide content in sodium borosilicate glasses, the refractive index (μD) rises to a maximum as also does the annealing temperature, while the coefficient of thermal expansion reaches a minimum and then rises. The durability, or resistance to water and hydrochloric acid reaches a maximum when the glass contains about 12% of boric oxide and subsequently falls off very rapidly. There is, accordingly, a limit to the usefulness of boric oxide in glass.
THE DEVELOPMENT OF TRANSPARENT COLORED GLASS IN AMERICA FOR GOGGLE PURPOSES1
Authors: Hettinger Edwin L.
Published: June 2006

Prior to the World War all of the goggle glass was imported from abroad. Necessity made us develop it in this country. Today all of the colors used for goggles are made near Pittsburgh. Glass is blown into large balls which are cut into strips and then cut into circles. Average thickness of glass is 2 mm. Average diameter of balls, 36 inches. Shades are graded into light, medium and dark. Colors are amber, smoke, fieuzal, amethyst and blue.
FACTORS AFFECTING THE WARPAGE OF SHEET IRON AND STEEL IN ENAMELING1
Authors: Danielson R. R. , Hartshorn T. D. , Harrison W. N.
Published: June 2006

The effects upon warpage of different methods of cleaning the metal, durations of firing periods, scaling practices, gages of metal, types of enamel, etc., are studied. Test pieces 16 × 16 inches are employed, several commercial enameling irons and steels being used and compared. Warpage is determined by obtaining the areas on five evenly spaced, vertical planes, parallel to one edge of the test piece,‘included between a flat, horizontal base plane and the contour of the test piece resting thereon. The average of the five areas in square centimeters is used to express numerically the degree of warpage.

The conclusions are: (a) A wide divergence between the expansivities of the enamel and the metal base induces warpage, (b) there seems to be less tendency for the scaled metal to warp than for that cleaned chemically, (c) thin metal is more sensitive to the factors affecting warpage than thicker metal,(d) sudden, irregular cooling induces warpage, (e) tendency to warpage is reduced by properly supporting the ware during firing and cooling.
UTILIZATION OF GEORGIA KAOLINS IN THE MANUFACTURE OF FACE BRICK1
Authors: Stull R. T. , Bole G. A.
Published: June 2006

The availability of the sedimentary kaolins of Georgia for the manufacture of face brick, when blended with sutficient flux‐bearing rock (aplite) and sand, has been demonstrated. Two representative clays were used. Four samples of aplite were mixed with varying amounts of the kaolins and fired to cones 6 and 12. The physical properties of the fired specimens are tabulated. Using this information as a basis, semi‐commercial tests were run using varying percentages of kaolin, aplite and sand. Bricks were made up by both the dry press and stiff mud process and fired to temperatures around cone 9. Trouble was experienced due to excessive shrinkage and due to crack. ing with mixtures containing no sand. Due to lower drying shrinkage, the dry press method of manufacture was found to be better suited to certain mixes than the stiff mud process. A mix was finally produced which went through the stiff mud process nicely, dried safely, and burned to a dense, light buff body at cone 81/2. The total shrinkage of this body was comparatively low.