Since there is no standard size for cement barrels, the capacities vary considerably, Portland cement barrels ranging from 3.1 to 3.6 cu. ft., while natural cement barrels contain from 3.4 to 3.8 cu. ft. In Germany cement is packed to weigh three hundred ninety-six pounds per barrel, gross, the net weight being about three hundred seventy-five pounds. American Portland usually weighs four hundred pounds gross or about three hundred eighty pounds net.
In 1896 the Boston Transit Commission had a number of measurements made of the capacity of Portland cement barrels, and these have been compiled by Mr. Sanford E. Thompson.1 Table 58 presents some of the averages obtained from this series of tests. It is seen that the capacity of the barrels varied from 3.12 to 3.50 cu. ft., the mean volume being 3.29 cu. ft. The difference between the capacity of the barrel and the volume of the packed cement contained is due to the fact that there is usually a small space beneath the head not filled with cement. A barrel of packed cement makes about 1.25 barrels, measured loose.
271. Natural cements made in the East are packed to weigh three hundred pounds net, while some of the Western natural cements weigh but two hundred sixty-five pounds per barrel net. Any of the natural cement factories will doubtless pack their cement to suit customers on large orders, and there seems to be little reason for this variation in weight between the West and the East. There would perhaps be some trouble in getting three hundred pounds of a very light, finely ground, natural cement in the ordinary sized barrel, but two hundred eighty pounds may be put in a barrel without difficulty, and it would seem that a compromise might be made on this weight.
1 Engineering News, Oct. 4, 1900.
Height of barrel between heads, feet ....
Capacity between heads, cubic feet.....
volume of packed cement in barrel, cubic feet .
volume of loose cement in barrel, cubic feet . .
Net weight of cement in barrel, pounds . . .
Weight per cubic foot of cement as packed in
Weight per cubic foot, loose, pounds ....
Note. — Results are averages of thirty-one tests with seven brands, four of which were American. The above data compiled by Sanford E. Thompson and published in Engineering News of Oct. 4, 1900.