C—ls

Slags. First slag- p er Cent. Iron . . .. . . .. .. . . 4-22 Second slag Iron .. .. .. . . 7-59 Third slag— Iron .. .. .. .. .. .. 2-26 Lime . . .. .. .. .. .. 42-10 Steel Ingots. . The steel ingots were forged down to square bars, and cold and forging tests carried out- on them at an adjacent works, and other bars were forwarded to London for further tests. The forging tests made in Darlington were satisfactory; the material forged under the hammer without any signs of red shortness, and welded, fairly well. A cold-bend test was made by bending under the steam-hammer a 1 Jin. square bar, and this bent through an angle of, 155° before fracture. The results of mechanical tests made in London were as follows :— Tensile Tests. Laboratory No. 3271. Ultimate strength, 49-6 tons per square inch. Yield-point, 35-4 tons per square inch. Reduction of area, 23 per cent. Elongation in 4v/area, 15-2 per cent. Fracture, two-thirds crystalline, one-third silky. Cold-bending Tests. Dimensions, 1-40 in. x 1-00 in. (planed). Bent over 3-in. - diameter bearing. Broke after passing through 65°. Crystalline. These results were quite satisfactory, and about what would be expected from steel of this grade. Castings. The pigs from heats 9 and 10 were mixed together and melted in the cupola, the metal then being cast into test bars and different castings. One of the 2 in. x 1 in. test bars tested at the works for transverse strength gave the following results : Breaking-strain, 24-75 cwt. ; deflection, /„ in. Other bars were brought to London for further mechanical tests. The results of these tests were as follows : — Tensile 'Test. Laboratory No. 3270. Dimensions : Diameter, 0-565 in. ; area, 0-251 sq. in. Tensile strength, 9-1 tons per square inch. Appearance of fracture, sound. Transverse Test. Laboratory No. 3269. Dimensions, 1-01 in. x 2-04 in. Breaking-strain, 27-5 cwt. Final deflection, 0-51 in. Appearance of fracture, sound.

400 K.W. SNYDER ELECTRIC FURNACE.

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