Page:Encyclopædia Britannica, Ninth Edition, v. 13.djvu/343

 IRON 327 As yet the process does not seem to have attracted the attention, or to have produced the results, that were expected of it some two or three years back. Eaton s Process (Brown s Process). In connexion with the history of the dephosphorization of pig iron, and its conversion into steel, the experiments of Eaton (of Brooklyn, N.Y.)are of interest; in 1860 he patented the production of steel by the fusion together of cast iron and alkaline carbonates or by the exposure of the cast iron to the decarbonizing and purifying action of these salts in a fused state. No practical use seems to have been made of the process. Recently the subject has been investigated by Drown, who finds that cast iron plates immersed in melted sodium carbonate for several days become converted into malleable iron to a greater or lesser depth by a pro cess substantially the same as that occurring when iron oxide is used as the &quot;cementing&quot; agent ( 22), so far as the removal of carbon is concerned, but differing in that silicon and phosphorus are also largely oxidized and removed. Thus the following analyses represent the purifying effect of a seven days treatment of a bar of pig iron : Original Cast Iron Bar. After Treatment for seven days. Interior of Bar after Treat ment. Layer of outer Metal & inch deep. Next layer of A incn deep. Third layer of iV inch deep. No. 1. No. 2. Carbon 3-56 1-38 0-87 0-11 0-82 0-45 0-057 0-574 0-015 0-33 1-09 0-67 0-166 0-607 0-201 0-942 1-281 0-776 3-58 1-38 0-91 3-293 1-362 0-911 Silicon Phosphorus .... i Carbon Silicon Phosphorus 25. Machinery and Appliances employed in the Manu facture of Malleable Iron. When a ball has been prepared in the puddling furnace, it consists of a loosely coherent spongy mass of iron of doughy consistency with fluid slag filling up all the interstices and dripping from it. The first thing to be done with it is to hammer or squeeze it into a somewhat more compact mass or bloom, the fluid slag being thus to a considerable extent removed ; the mass is then further hammered or rolled into rough bars, by which time it has so far cooled down that before it can be further manipulated it must be again heated up to welding heat ; previously to this heating it is cut up into slips which are &quot; piled &quot; on one another and &quot; fagoted &quot; together with iron wire, and after being heated up again are hammered into a bloom and rolled or otherwise worked into bars, plates, rods, &c., as required. For very coarse bars piling and reheating is not always necessary ; but for the better qualities of &quot; merchant iron &quot; these operations are carefully gone through, often more than once ; the size of the piles, the way in which the separate portions are arranged in them, and the mode of rolling, &c., depending on the form ultimately desired ; thus the arrangement is somewhat different when T i ron is intended to be made from that adopted for plates, and so on ; the pile being made in the former case pyramidal or somewhat J_ shaped, in the latter of rectangular section. FIG. 40. Alligator Squeezer. Formerly the balls were squeezed by an &quot; alligator &quot; cr &quot; croco dile&quot; squeezer such as that represented in fig. 40, and were then &quot;shingled&quot; by shingling hammers, such as the &quot;tilt&quot; hammer (where the hammer forms a lever with the fulcrum in the middle, a cam pressing upon one end serving to depress that end and raise the other which carries the head) and the &quot; helve &quot; hammer (where FIG. 41. Helve Hammer. I. Elevation. II. Plan. the fulcrum is at one end, the lifting cam being at the other, and the hammer head between the two, as near the cam as possible, fig. 41) ; these arrangements were usually worked by water-power. &quot;With the increased use of steam-power more powerful squeezers were em ployed. Fig. 42 represents Brown s revolving squeezer, the ball being made to pass between two rotating cams which flatten it out, and sub sequently between the second of these and a third which carries the operation further ; in more powerful machines of the kind a larger number of cams still is employed. Fig. 43 represents another form of rotary squeezer, in which, by the friction of the revolving inner wheel C (studded with blunt projecting teeth) p 42. -Brown s Eevolving Squeezer, the ball D is urged onwards from A where it enters to E where it leaves, and is con sequently flattened out and squeezed by the pressure between C and the outer circle BB. The use of the steam hammer, however, has now largely superseded these arrangements for the produce of hand- puddling furnaces ; for larger masses hydraulic squeezers are often used ; thus Siemens employs an hydraulic compressor in which three or more hydraulic rams simultane ously advance horizontally to the ball in radial directions, the ball being mounted on a turntable, so that when the rams retire it can be shifted round so as to present fresh surface to the rams ; after lateral compression, a vertical ram or screw descends upon the ball so as to compress it in a new direction. For the large balls obtained in tue Banks furnace, &c., a powerful _ squeezer is used, in principle ana- Fl - 43. Revolving Squeezer, logons to Brown s (fig. 42), having two rollers at the base revolv ing in the same direction, and a large eccentric or cam geared to them and also revolving in the same direction, the end being hammered up by a horizontal steam hammer when the pressure forces the metal outwards. Fig. 44 represents a single-acting hammer after Nasmyth s con struction (Cave smodification), in which thecylinder is fixed and the