204
MODERN GAS WORKS PRACTICE
noted th.at clays and related materials have no sharply defined melting points, and the definition of refractoriness adopted refers to the temperature at which the angular edges of the material begin to lose their angularity when heated under the conditions stated.”
SOFTENING POINTS OF SEGER CONES
Cone No. Cent. Fahr. Cone No. Cent. Fahr.
022 600 1112 9 1280 2336
021 650 1202 10 1300 2372
020 670 1238 11 1320 2408
019 690 1274 12 1350 2462
018 710 1310 13 1380 2516
017 730 1346 14 1410 2570
016 750 1382 15 1435 2615
015a 790 1454 16 1460 2660
014a 815 1499 17 1480 2696
013a 835 1535 18 1500 2732
012a 855 1571 19 1520 2768
011a 880 1616 20 1530 2786
010a 900 1652 26 1580 2876
09a 920 1688 27 1610 2930
08a 940 1724 28 1630 2966
07a 960 1760 29 1650 3002
06a 980 1796 30 1670 3038
05a 1000 1832 31 1690 3074
04a 1020 1868 32 1710 3110
03a 1040 1904 33 1730 3146
02a 1060 1940 34 1750 3182
01a 1080 1976 35 1770 3218
la 1100 2012 36 1790 3254
2a 1120 2048 37 1825 3317
3a 1140 2084 38 1850 3362
4a 1160 2120 39 1880 3416
5a 1180 2156 40 1920 3488
6a 1200 2192 41 1980 3560
7 1230 2246 42 2000 3632
8 1250 2282 — — —
TESTING UNDER STRESS
Although the conditions of testing in furnaces such as described above coincide with. those prevailing in a retort setting in respect of temperature, it must not be forgotten that the fireclay material forms part of a structure, and is, in consequence, subjected to varying degrees of stress (chiefly compressive) according to its function in the setting. la this respect a series of tests have been carried out by J. W. Mellor 1 to determine the effect of stress upon ultimate refractoriness.'
1 Report of Refractory Materials Committee, 1918.