LOSS OF IRON BY OXIDATION IN CUPOLAS.
protected and unprotected plan seen in heats Nos. 3 to 8, it will appear how unreliable are the data as to how much sand or scale one is crediting to iron when weighing the charges of sand-coated pig t irons for regular cupola practice. To avoid this uncertainty, I adopted the idea of taking gray iron cast in chill moulds for both sides of the cupola, coating that for one side heavily with some heat resisting material (by giving each three coats and drying them in an oven after every coating), and charging the other side with the surface of the chilled or sandless gray iron exposed. By weighing the iron before it was coated I knew exactly what weight of iron was going into the respec-
TAIII.K 65.—COMPARATIVE OXIDATION TEST OK IRONS CHARGED ON
MICH AND I.ONV 1JKDS OF FUEL. SEE 1'AGK 315.
Heat No. (). Heat No. 10. Heat No. ir. Heat No. 12.
Kind of metal charged. Chill rollsmi-protected. Chill roll s iiii-protected. Chill rolls coated with lead wash. Chill rolls coated with lead wash.
Weight of ehar^'es each side. . . <).) Ibs. 7^ Ibs. 7S Ibs. 100 Ibs.
Blast, on. ... ........... ...'....'* ....... ^7.777".77Z — ,,_55 4.27 3-42 3-33 '"
Hijuh bed running ............................ 4 -3s 3-50 3-45
J^>w bed running. 4.00 4'^ ^l ••'•' "M-7-X T,,^()
ilitfh bed all down. 77 7 7. 7.. 77777777777 "7j.nl, 4.4* 3.03}^ 4 05
I/>w bed all down ............ ..... 4.o» 4-4-1 4.56^ 3-55
Weight of iron obtained from high bed (u Ibs. '» ox. 70 Ibs. 7 ox. 72 Ibs. () OX. 96 Ibs. 12 OX.
Weight of iron obtained from low bed.. 62 Ibs. U) OX. ~~"l'll>."~ 70 Ibs. K ox. "a Ibs7 72 Ibs. 14 ox. ...... ~2 I'bsT" 96 Ibs. 14 oz. -yj---
I/>ss of iron from low bed 10 OX. """ i ib."™ () OX. a Ibs. ..... 7 ox. ..... 2 Ibs. 4 ox. "^ Ibs7~
6 ox. S ox. 2 OX. 2 OX.
tive sides of the cupola. In. reality, I consider this the only true way of making a comparison between chillle on the sand r.i-,1 toll, and whieh were eharj'.ed on one side, u htle the elullerl tolls \\ejo ehau;« d on the oth«T, of the ettpola, tor heat-, No-, land '. 1-or Itfat-. No-. •; io ;=; all t lull Hills \vc ie n-,cd jot both sides, the only «li!l'i'frui'i' ln-ill>' the .lulls i<»i itttc side xvei rotated as d«.:st.:t ihed on pa^es ,u •„ ,i j and ;i,nds pe!' (on of iron, or a ratio of 7.7 iron to i coke, in onler to deliver the melted iron in the same condition as on an ordinary day. In other words, an additional fuel consumption <>!' a little over 3,h per cent, is needed under the above conditions...................... 3,658 units £