GENERAL DIVISIONS OF THE INDUSTRY

The Open-Hearth Furnace.

The m a m ifa c tu re of steel castin g s in th e U n ite d S ta te s classifies itself into divisions as to p ro cesses;

and in to b ran ch es or sections as to uses in one o r

* “ L ist of M anufacturers of Steel C astings in th e U n ited S t a t e « and C anada,” Issued in 1922 by the Steel F o u n d ers’ Society of America, enum erates Foundries whose com bined capacities a f t e r slight and reasonable corrections, are found to to ta l 1 966 900 n e t

to n s per annum . * “ et

several divisions. N a tu ra lly th e la rg e st division, considered from a to n n a g e s ta n d p o in t, is t h a t of th e o p e n -h e a rth , necessarily sub-divided according to th e basic o r acid n a tu r e of th e fu rn a c e bottom . The to n n a g e s of steel castin g s being m ade to-day in th e S ta te s from basic o p e n -h e a rth fu rn aces are n o t ap p reciab ly d ifferen t from those produced from acid o p en -h e a rth fu rn aces. I n 1917 w hen steel c a stin g p ro d u ctio n w as a t a very high level, A m eri­

can o p e n -h e a rth fo u n d ries delivered 1,357,700 n e t tons, of which 54 p e r c en t, was basic an d 46 p e r­

cent. acid. A t th is w ritin g , sta tis tic s for p roduc­

tio n in 1922 h ave n o t been a u th o rita tiv e ly re p o rte d .* T here is little d o u b t t h a t th e figures when com piled will to ta l less th a n in 1917, when th ey exceeded any re p o rte d up to th e p re se n t tim e for any o th er year. E a s te r n o p en -h earth foundries favour th e acid bottom to very la rg e e x te n t, while th e basic bottom is chiefly em ployed in th e m iddle w estern sta te s. T his is m ore a m a tte r of use of th e p ro d u c t th a n i t is of g eographical location, as related to source of m elting-stock supply.

D espite th e trem en d o u s grow th of th e electric fu rn ace in d u s try in re c e n t y ears in th e S ta te s, to be d ealt w ith la te r, th e re is no reason now to su p ­ pose t h a t th e to n n a g e s of o p e n -h e a rth steel cast­

ings an n u ally m ade in A m erica w ill soon be ap preciably red u ced beyond p re s e n t p ro d u c tio n . W hile th e b e tte r su ita b ility o f th e elec tric fu rn ace is g ra d u a lly becom ing d e m o n strated for c e rta in castin g s h ere to fo re produced in g re a te r or less degree from th e o p en -h e a rth . T he c o n sta n t developm ent of new uses fo r all k in d s of steel castin g s w ill probably com pensate fo r to n n a g e losses su stain ed by o p en -h earth fo u n d ries in p re ­ ferred m a n u fa c tu re elsew here of p a r t of th e to ta l p roduct. C onsidering q u a lity an d cost, th e open- h e a rth is ad m irab ly a d a p te d for th e m ajo r p o rtio n of th e to n n ag es of steel c astin g s m ade in A m erica.

The Electric Furnace.

N ext in size to th e la rg e st, or o p en -h earth division, is t h a t of th e electric fu rn ace, also sub­

divided according to th e n a tu r e of its lining.

* Figures showing tonnage production of various classes of castings are tak en from a n n u al “ Special Statistical B ulletins ” of th e American Iro n and Steel In s titu te , which show production in gross tons.

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H ow ever, th e r e is now n o th in g lik e th e e q u a lity of fa v o u r for basic an d acid lin in g s as e x ists in th e case of th e o p en -h earth for fo u n d ry use. T o-day probably 90 p e r c en t, of th e steel c a stin g s p ro ­ duced from A m erican elec tric fu rn a c e s a r e of acid steel. P e rh a p s e ig h t y e a rs ago th e balance w as in fa v o u r of th e basic e lec tric fu rn a c e . W ith in th e la s t five y ears th e p ro p o rtio n re p re s e n tin g th e acid lin in g fo r th is ty p e of m e ltin g u n i t em ployed fo r th e fo u n d ry h a s grow n v ery ra p id ly .

The p re s e n t to ta l c a p a c ity of th e fo u n d ries m ak in g e lec tric steel fo r c a stin g s in th e U n ite d S ta te s is now pro b ab ly 250,000 n e t to n s p e r y e a r, or roughly, 13 p e r c en t, o f th e to t a l steel fo u n d ry cap acity . A ctu al p ro d u c tio n fro m such fo u n d rie s in 1921 re p re se n te d t h a t p ro p o rtio n o f all ste e l c astin g to n n a g e s th e n p ro d u ced . P ro b ab ly th e p ro p o rtio n fo r la s t y e a r an d t h a t fo r th e c u r r e n t y e a r will each exceed 13 p e r cen t.

The d evelopm ent of th e e lec tric fu r n a c e in d u s try in th e S ta te s h a s been of e x tr a o rd in a ry in te re s t.

The first electric fu rn a c e s to m a k e ste e l fo r c a st­

ings in A m erica w ere in sta lle d in 1908, w hen 55 to n s of such castin g s w ere th e r e p ro d u c e d . I n 1920 th is o u tp u t h ad grow n t o 173,819 n e t to n s.

This y e a r ’s o u tp u t w ill p robably re a c h , if i t does n o t exceed, t h a t figure. E x p a n sio n of th is d iv isio n of th e A m erican in d u s try d u r in g th e la s t d ecad e has been 2,000 p e r c en t. F a c to r s t h a t h av e caused th is gro w th h av e inclu d ed q u a lity of th e p r o d u c t; a v a ila b ility of reaso n ab ly -p riced e le c tric pow er; an d th e h ig h p ric e a tte n d in g t h e s c a rc ity of coke su ita b le fo r use in co n v erters. T he vessels la s t nam ed have yielded to th e com m ercial a n d m etallu rg ical su p e rio rity of th e e le c tric fu r n a c e in m any foundries.

The Converter.

The c o n v erter ta k e s th i r d r a n k in im p o rta n c e as re g a rd s to ta l to n n a g e s pro d u ced in th e S ta te s . This division of th e in d u s try is g ra d u a lly lessen in g in volum e of o u tp u t. T he te n d e n c y to disp lace th is m edium an d to s u b s titu te th e r e fo r th e e le c tric fu rn a c e m ay be re a d ily a p p re c ia te d by n o tin g th e fa c t t h a t from 1914 to 1918 inclusive, th e r e w as an u n v ary in g in crease in th e to n n a g e of c o n v e rte r steel castin g s m ade in th e U n ite d S ta te s , u n til in th e y e a r la s t nam ed such p ro d u c tio n to ta lle d

a b o u t 179,000 n e t to n s ; w hereas in t h a t y ear

1 2 1 ,0 0 0 n e t to n s of electric steel castin g s w ere pro­

duced. I n c o n tr a s t w ith th is we find as before sta te d , n e a rly 174,000 n e t to n s of electric steel castin g s delivered in 1920, w hile only 117,577 n e t to n s w ere sim u ltan eo u sly m ade by m eans of th e converters. P ro b ab ly , to -d ay , th e o u tp u t of steel castin g s from co n v erters is n o t g re a te r th a n half of t h a t pro d u ced fro m elec tric fu rn aces in th e U n ited S ta te s. C o n tin u an ce of th e p re s e n t ten- dencv to s u p p la n t th e c o n v erter w ith th e electric u n it can be p re d ic te d w ith o u t h azard . W hile, as before in d icated , q u a lity h as been an im p o rta n t facto r in th e su b s titu tio n , can d o u r ju stifies th e adm ission t h a t th e chief elem en t in m any cases in displacing th e c o n v erter in th e S ta te s w ith th e electric fu rn a c e h as been th a t of o p e ra tin g cost.

T here is no sub-division of th e co n v erter division of th e A m erican in d u s try as to th e n a tu r e of lin in g . The m etal produced is acid. E fforts to m ake basic co n v erter steel in th e S ta te s h av e been ex p eri­

m ental, in sig n ifican t as to re la tiv e effects on to n ­ nage, an d so f a r as th e a u th o r knows, u n re la te d to foundry purposes. This, of course, is due to th e n a tu r e of m a te ria ls re q u ire d for co n v erter o p eratio n , as m u st be g en erally know n abro ad as well as a t home.

The Crucible.

The la s t g en eral division in to w hich th e in d u s try has been divided in th e S ta te s, is t h a t of th e crucible. I t is v ery d o u b tfu l if one m ay t r u t h ­ fully say th e re is y e t such a division ex istin g . C er­

ta in ly th e r e is none such in a com m ercial sense.

The w rite r h as no p erso n al know ledge t h a t an y crucible steel is m ade to-day in th e S ta te s for castin g purposes. I n 1921 th e r e w ere only 824 n e t tons of crucible steel c astin g s m ade in A m erica.

Ten years previously th e r e w ere m ore th a n 23,000 n e t to n s so produced. T he crucible h a d a long and highly useful career, b u t was in e v ita b ly displaced by u n its capable of m uch m ore econom ical p ro ­ duction. I t would be superfluous to ela b o ra te on th is fa c t, since i t is a m a tte r of common know ledge.