ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16265.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

摘要:

ABSTRACTActual problems, the cause and possible solution are described. Calculations are given showing the economies of good drainage, well upkept equipment, and sane management of clay mines. Observations show that clay is wasted and mining hazardous and unnecessarily expensive in several of the clay mines examined. Recommendations are made.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16266.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16267.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16268.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16269.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16270.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

摘要:

ABSTRACTThis paper deals with manufacture, properties, and uses of gypsum plaster in the various branches of the pottery industry,i.e., in white ware, stoneware, electric insulators, sanitary ware, etc., in the terra cotta industries, in plate glass, and for sundry minor ceramic uses.The methods of producing calcined gypsum are briefly described and then follows a discussion of the physical and chemical properties of the three principal forms of calcium sulphate as used commercially, (1) crude gypsum, (2) calcined gypsum (gypsum plaster), and (3) gypsum casts of set‐up gypsum plaster.The proper methods of mixing, blending, and casting plaster are described, with graphs showing effects of varying such factors as consistency, mixing time, etc. Methods of testing plasters are briefly discussed. Considerable attention is given to difficulties commonly encountered in the use of plaster, with causes and methods of coffeetion. This includes the use and abuse of plaster molds, such as “rotting” of molds, “burning” of molds, efflorescence, etc.The properties of gypsum plaster can be varied within wide limits to meet special requirements. It is shown how the plasters used for pottery and terra cotta molds are quite different from those used in bedding plate glass.The purpose of the paper is to give a more complete picture of how gypsum plaster may and should be used in theceramic i

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16271.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

摘要:

ABSTRACTAbout 300 panels have been erected to determine the effect of some of the various factors of different brick, mortars, workmanship. and design in causing leaky brick walls. The brick varied in absorption from 0.6 to over 12% of their weight when placed flat side down in 1/8 inch water for ten minutes. The mortars included both lean and the richest mixes of lime and Portland cement in varying proportions and of a large number of masonry cements. Most of the panels one brick in thickness leaked in half an hour on being sprayed with a hose. A very few mortars were found that were quite tight. Those panels with an air space between the front and the backing allowed no water to pass clear through the wall. Many panels have been broken in flexure with very interesting and important results. Other panels have been built to test out interior ventilation of walls, and many other points have been studied.

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16272.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16273.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY

摘要:

ABSTRACTThis article indicates the results obtained by introducing into a porcelain mixture an unstable nonplastic aggregate, consisting chemically of alumina, silica, and a fluxing oxide, which latter has been heat‐treated in such a manner that its crystallization has been arrested. Upon subsequent kiln Wing, crystallization takes place and the arrested crystals grow, orienting themselves in such a manner as to form a network of interwoven crystals. The effect of this crystallization improves the physical properties of the porcelai

ISSN:0002-7820    

DOI:10.1111/j.1151-2916.1930.tb16274.x

出版商:Blackwell Publishing Ltd    

年代:1930

数据来源: WILEY