Standard and tentative methods of sampling and testing highway materials : recommended by the Second Conference of State Highway Testing Engineers and Chemists, Washington, , Feb 23-27, 1920 . ?ig. 20.—Open-cup oil tester. SAMPLING AND TESTING HIGHWAY MATERIALS. 43 25. FLOAT TEST FOR CONSISTENCY. The float apparatus consists of two parts (see fig. 21), an aluminum float or saucer,a, and a conical brass collar, b. The tv/o parts are made separately, so that one floatmay be used with a number of brass collars. In making the test the brass collar is placed with the small end down on the brass
Standard and tentative methods of sampling and testing highway materials : recommended by the Second Conference of State Highway Testing Engineers and Chemists, Washington, , Feb 23-27, 1920 . ?ig. 20.—Open-cup oil tester. SAMPLING AND TESTING HIGHWAY MATERIALS. 43 25. FLOAT TEST FOR CONSISTENCY. The float apparatus consists of two parts (see fig. 21), an aluminum float or saucer,a, and a conical brass collar, b. The tv/o parts are made separately, so that one floatmay be used with a number of brass collars. In making the test the brass collar is placed with the small end down on the brassplate, which has been previously amalgamated with mercury by first rubbing it witha dilute solution of mercuric chloride or nitrate and then with mercury. A smallquantity of the material to be tested is heated in the metal spoon until quite fluid,with care that it suffers no appreciable loss by volatilization and that it is kept freefrom air bubbles. It is then poured into the collar in a thin stream until slightlymore than level with the top. The surplus may be removed, after the material hascooled to room temperature, by means of a spatula or steel knife which has been slightlyheated.
Size: 1811px × 1380px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1920, booksubjectroadmat, bookyear1921
