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Show i mi WELDING BY ELECTRIC ARC Powerful Current That Melts Iron and Steel In a Few Minuter. Tho person in tho aoiompniUl.iK Illustration Is not a character in cue of Jutes Verno's romances, but n wjrk-mnn wjrk-mnn engaged In welding Iron by ime of tho now processes employing (ho electric arc. The hend must bo .mi-jilctoly .mi-jilctoly protected to nvold Injury ??om tho Intcnso radlntlon hence (he grotesquo head-gear. Mr. C. H. Ajel. of tho Wcstlnghouso Company, vlio describes these now processes In tho American Machinist, tells us hnt thero nro two chief typos tho Hvnar dos, which uses but a slnglo olectwdo, and tho Zoroncr, in which two. nro employed. Ha snys: "For small work nnd for work whero n certain degreo of nccuracy nn& refinement re-finement Is necessary, tho Zeiencr process will glvo rather better remits than tho Hennrdos, for tho njsoii that in tho former tho arc Is, ooin-pnratlvoly ooin-pnratlvoly speaking, under closj reg- The Benardos Process Ui Use, ulatlon, whllo in tho lattoi thcro Is only such regulation ns my bo obtained ob-tained hy hand. Nevertheless, for genoral work tho llcnnrdoy process, on account of Its slmpllclt. Is to bo prnforred. "It Is necessary to conduo; tho welding weld-ing In an inclosuro, ns thy intense rays of tho arc seriously Interfere with any other work In tho isunedluto vicinity. For a similar reason, when tho Hennrdos process Is irmploycd, welder should bo thoroughly shielded, eyes as well as body. A head-gear of canvas or of stoVcplpa is readily mado nnd fitted with a sniiill projecting projec-ting window of thick cnlced glass, Gloves provided with long gauntlets will nnswor for the hands, -vhllo tho ordinary clothing, If not too thin, will sufllco for tho rest of tho tody. Exposure) Ex-posure) to tho dlrnct rayB cf tho arc causes nn Irritation of tho sltlu In effect ef-fect much llko sunburn; tlw skin reddens red-dens and subsequently pcolu but with no moro serious coiiBeqimiccB, A short trial will, however, h. moro effective ef-fective In demonstrating tho desirability desirabil-ity of caro In this matter than any words of caution. "Whon tho Zerener procnjn is era-ployed, era-ployed, howovcr, tho welding Is usually usual-ly on a much smaller scale, and It Is then only neccssnry to pjutect tho eyes by n pair of suitable colored glasses." Tho method of operation In tho single-carbon process Is thus described by Mr, Auel: "Assuming now that cvctythlng Is in rcadlnesB for making n weld, tho operator places himself in fiont of tho casting, holding In ono hand the carbon car-bon (negatlvo) clcctrodo by means of nn Insulated handle, and having within convenient reach of tho other hand the matcrlat to bo usod as tiller, either Iron rod, . . . bits of broken steel castings, or small punchtnga from boiler plate. Ho then pulls the hood down over hla head, touches the carbon car-bon olectrodo to the casting, . . , thereby closing tho circuit and. thus producing the arc. As soon as tho nro Is sprung, tho carbon olectrodo should be withdrawn to a dUtanca of at least two Inches, moro If possible, and the arc continued until tho melting melt-ing temperature of tho metal 1' reached. "If it is not possible to maintain the arc at the proper distance, or If It Is too Intenso, tho depth of the trlnngular plates In the water rheostat or the number of grids In tho resistance resist-ance should be altered accordingly, The arc, Instead of being concentrated concentrat-ed on one spot, should bo given a rotary ro-tary motion In order to heat the casting cast-ing thoroughly In tho vicinity of tho proposed weld. "When tho melting temperature Is reached, either the Iron rod, small bits of steel castings, or punching of boiler plate aro fed In'o the boiling metal. This feeding Is continued, tho arc meanwhile also being maintained, until the weld Is completed. To make the casting conform to u particular I shape, or tn glvo It n smoother finish or closer grain, tho surface of the weld may be hammered while cool. Ing." |