Manufacture of Nickel Steel Axle Housings at Foundry of Moreland Motor Truck co.

By Ethelbert Favary Consulting Engineer, Morelant! Motor TruclT Co. paper Reail Beforb the Western Metal Congress.

During the rvar, rvhen it r,vas difficult to obtain steel castings- fr.om the East, the company with which I am con_ nected built its own electric furnices from specifi"ution, furnished by the Vonbaur Company. In this iy; ;h;A: rect arc with a non-conducting heaith is used; *e employ three-phalg al ternating current-three carbons .r, t. ri' J ti'. furnace. The larger. (3-ton) furnace is provideJ-;i;i; ;r;: mauc regutatron ot the arc; the smaller (Ifu_ton) furnace. is hand regulated.

which we must consider to insure good castings. They are -the carbon, the manganese and ihe silicon. -Srfof,"i ""J ph-osphorous-the two most undesirable

;;; affected by refining and need not be considered, .. tnly "r" taken care of automatically, as mentioned before, Since the oxygen is introduced as rust or scale of the scrap iron used, and later as bre, the silicon

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Th: electric process ofiers several distinct advantages:_ It is flexible and is very weil suited for the manufactirre of castings. The temperature can be controlled within close lrmrts. 'I'he deoxidation and reduction can be as thorough as desired and phosphorus and sulphur can be eliminat-ed ganese.upox being oxidized become manganese silicate and enter the slag. The carbon is oxidizecl tJ carbon monoxide and esca.pes as .a -gas. The deoxidizing process does not nave to be carrred to such a final degree in the acid type furnace. The iron oxide is lowered to i'point *n.r. ;l--JJt. practical conditions. The deoxidizing agents used are man- g'an€se in the form of ferro mangane-se isilico" i" trt" roi* of ferro silicon; and carbon titaiium, which i, ; p;;p*;; compound. By using the latter instead of pure "lu-irro* we find the physical properties greatly improved_t";;il; strength as well as elongation and reduitiori in area.

The silicon should bi- added first, well before iap, and the manganese later. , Silicon is not only a dec,xidizer'bui it is efficient as a degasifier.

Refractory Materials

As refractory materials we now use vitrified briik (for_ merly used silica brick) for the roof and the siae waii;-uil;;" the slag line. Below the slag line we use silica brick and silica sand sintered by the electric arc. We nna th;i ih; p.urchase of the best r-efractory materials is the .fr."p..t in the) end.

We pay the utmost attention to the raw material which rve _purchase and we_-only use scrap of a predet;r;i;;J analy,sis. Rust is eliminated, rvheie .*."r.i,,r., itrr.rgf, tumbling.

Manufacturing Axle Housings

as completely as necessary. In the acid process the phos_ phorus is controlled by purchasing. scrap oi f.""*" ifr"._ phorus content while deoiidation iridures desulphurizri"": Electrically- produced steel has great density^ and ."" -ir. made free from blow holes, from slag and iro"t .oiUeJ S.asgs; it .is strong, jgugn and ductile]To produce ,i.f."l steel castings, th-e nickel alloy is added direc'tly to the bath betore it is transferred into the ladle.

Due to the {ow cost of the electric current on the pacific Coast, the cost for small furnaces,is very lorv i"d";;.- ii-i;; holever, necessary_ that the man in chaige have a thorough Knotvledge ot the electric furnace method. In order to pr-o_ duce good sound steel it is a-bsolutely necessary that the metal does not contain-impurities, o*ide, or gases.

For the production of caitings the electric p-ro..r, offers great- advantages because a hi[h temperature is easily ob_ tainable and this rvill reduce the ..i"p to., ."."""i.."a with.other systems and the furnace -uy ir. ,ir"d fo. tir-.-prl- duction of both iron and steel castings. A trot m;i"i'i; ;i; necessary.to run thin sections rvhen outlines must be sharp. ly maintained.

rn the acid proceslif#'f.::".:iil onry three elements.

*See "The Manufacture of Electric Steel,'by Frank T. Sisco.

When we first started,td p,roduce axleiousings for our six-rvheel trucks, several diificulties wer. en.orintered; I will mention them for the benefit of others rrt o -"y *i.h to_produce complicated castings.

11. th9 first samples which -were made like those shown rn .trg. l. rve found sh-rinking cracks in the corners at a, b and at c. These cracks developed because of the gr""i", mass of metal at these points, *hich adversely affectEd uni_ formcooling. To ovCrcome these the next step was to leave off the corners apd add extra metal to the ;;r".6 ;; shorvn F fig. 2, which rvere afterwards turned off. lo stitt more effectively eliminate cracks, metal chills (a) *.ie Ja_ ed, as shown, but at the present time metal chilli have been eliminated, and instead- a softer core is ur.a, -ti.fr-1, obtained by the employment of a softir binder for the sand. r. ne snrlnklng cracks at c were more difficult to overcome and we had to eliminate the circumferenlial rbr ""a-""ii longitudinal ribs, as shown at e. The .-itt ,i"g (;i b.'il-g attached to the ribs,.instead of to the outer ho-usi"'g, ;;;: not influence the shrinkage of the housing and therEiore a sound casting is produced free from cruJks. fhe iing i, necessary.to support the end of the chrome nickel sieel tube whrch supports the wheel bearings.

,tn l!.r. 5.aslinSs.we use about .3 to:31 of carbon, l/o ot nrckel is added to the bath. As soon as these castings are poured they are withdrarvn from the mold (the.""r"L;"t

(Continued on page 49.)