Document 7RY8nY50Y3e4Nd37Bg1DE0L8V

LIA22861 4Al LEAD INDUSTRIES ASSOCIATION 4*0 LCXINOTON AVCNUK NCW VOKK 17, N. . Jsnusry 26, 1955 SUBJECT MATERIALS THE RAILROADS BUI - V.'S, ST. ST 6? Lead To Koaibers of the Lead Industries Association! Attached please find a copy of an article entitled "Materials the Railroads Bvgr - The Story of Load," reprinted from "Railway Purchases and Stores," Docoobor, 195U, Issue. The second article In this series which will deal with the railroads u ao of load particularly In bearings, batteries and paints will appear In their February issue, and reprints will bo sent you when available. t*e hope you will find this reprint of interest. If you would like additional copies, wo shall be glad to supply then upon requost. Slnceroly yours. TH! I `ium ritnliir r*! 1 -- n-- - r i r* 'u p h --w;i 0 n ij .i > i i a'miiiirr-- '-' ' "--L LlM26bZ A. lAall.i fcW.-WI h*\ Materials the Railroads Buy ^Ae St&uf, Jlead ----------^ - ... ^ `^ ..u * . - * --| - t h i f-'-- ..... ' - R<*printH frrmj RAILW AY Ft `RCHASES A\D STORES DrcrmlxT, 19S4 ------ ----- - - ^ -- ' ^ .IWJiJUpiF Distributrd by LEAD INDUSTRIES ASSOCIATION 420 Lrvinton Avrtu* NrwYofi 17. N. Y. mi ii mmi N 2005.01 CMV iwfm* LIA22663 Materials the Railroads Buy No. 17 of a Snv The Story of Lead ROBIRT I.. ZIliGFQ.D AND DAVID M. B0RC1NA U MIIAM K*r> ASMS! AST 1U MU lUTAln. W.IMfTTMJ T. U At* tVIVTTMU.1 AMUOATHR Tlx* I'liiliil Statrn is, aixl lu Ui n for a great many years. tlx* principal lead producing cvxmtry of thr world. itirrcnth atxiHiutmg for alxtut Of) |*f cent of tlx* worlds Mfptit of approximately 1 .`Ml.CKO tons. (Amn< ru.il juantitir\ of had arc united iii 21) of tlx* 4S states ssith tlx* xs*strm stati*s predominant How* cscf. Mis v h im i\ tlx* largest prodiKing state with Malm, t'lali. (!o|orado. M'Hii.iii.i. Washington. OUalxm'.a ar.<! ittlxrs adding to tlx* supph each year. approximately in tlx* unh-r named Uy far tlx* major ptrtion of tlr lead (mix'd is I\ tiixh-rgronixl iiK*th<*d\ with tlx* ore generally containing galena. a had sulphide. aixl iimially aswmated with otlx-r nx*tals. notahly zinc and silver. Of comidriahly less commm-ial importantr an* Ox* ot!x*r h ad mnx r.iK, ctrnisitr. u load cadxmate. aixl angh*sitr. a h ad sulphate. Lend Ore Concentrated Before Shipment to MlIU Few miixs poxhuv oi<*s rit h rtxtugh or purr enough to lx* shipp'd dmxth to a smelter without iutemx*diatr pnvt'Nsimj. Mon* oftrn tlx* mitwr will struck* with a comparatively low grade of lead ofr On tlx* oth<*r liand. an orr ran lx* p Ih ix u ih n.ills rirh in had hut contain so tiimh /iix and u'pp f that sjx*x i.d trr.itnxnt U resum'd Ix foic shipuxnt ran Ik * math* hi a surlier vslx*rr |x*naltx*s may !x* irmimtl hy tlx* prrvncr of with irnpuritkn, ()h\i<Hsfy. it is ix/t I'cotHtmicafly frasihh* to ship on* containing only 10 jx*r rout, hi us say. of load content or on* containing inipnriti<*s that will p*nalizr tlx* miix'f. v> it Ix k o iix *s tx'cessary to coix.vntratr thr orr. Concentrating milh art* tlxtrforr located in mining airas wlxrr otx* or uxtre mining propertxn can haul tlx ir orr for concentrating and or removal of impurities The Flotation Proem At tlx* mill tlx* lead ore is cnidx-d c\tn*moijr fine, soux-tinx** to policies h*sv than 1 mm. in diameter, atxl treat*d h\ nix* of tlx* modern pnxesM's of mineral coiKvntrxtion. Tlx* remarkable flotation priKxu may lx* usol. a method siinplr etxmgh to di-strilx* Ixit (*nni* plicatixl in r\<*cution, and such an un|v>rtant aixl mar* vt'hxis riK-tallurgical development of tlx* twentieth century that it hav left a deep impression u j x h i thr h ad and practically alt otlx-r nx*tal mining iixhistrirt. Flotation is applicable principally to Mx* sulphide type of orr. fortunately tlx* commoixM \arn*ty, or to an oxide on* whiih has neeixed a preliminary sulphiding. Urn fls. tlx* flotation pnxess grtHr.dlv innstilnles taking fiix-h cnislxsl orr diluted with. say. foui tiroes as nmch 6 i*TV8wi I Looding or* in o Missouri food mim water, ami agitating tin* man violently with air in a tank to whuh a fraction id one p<*r cent of pine oil. with nr without small amount* of other suitable cltcmi* cals, has hem added. As a result of the agitation a froth containing nuwt of tl*r metallic constituents of tla* ore is formed on top of tin* tank while the valueless angue nutter remains unaffected at tlse bottom of tin' tank. The froth flows from tlie tank and is easily dried. Flotation practice has reached such a stage of per fection that extraordinarily efficient work is being done, not onh in extracting a single mineral from an ore, but also in v^parating tlie sexeral minerals in so-called complex oivv for example, an ore consisting of an intimate mixture of lead, topjier aikl aiie mineral*. For scars tin* treatment of many complex ores RifH<*d metallurgists, but with selective flotation as a tool, many mineral ch-posits ones* considered practically worthless luxe dm-cHpcd into important lead mitw*. Furthermore. nuny straight lead ores formerly believed too low* grade for economical treatment suddenly be* canto profitable posdhilitiex. adding greatly to the world's asailabb* h ad reserves. Flotation lias, to a considerable extent, supplanted earlier methods of concentration using gravitational methods of milling, that is. pulsating jigs, vibrating tables and many otlter machine's but the older mecl unical nv*tltods are used alone or with flotation in treating many ores for which the)* are particularly suited. Smelling Ixad concentrates wltrn they kavr the mill contain 40 per evut and upwards of lead. The riclier the lead content tlie letter, for it reduces transportation and smelting costs. Smelting is a continuous operation generally trmductid in blast furnaces. Before the concentrates can be charged into the furnace, they must be roasted to remove most of the sulphur con tained in the concentrates and to agglomerate the very Mop showing fh prima ry lood production oroos in fh# United Stotts. fh* sletchos orrond fho border show tomo of tho products which us* tood wr  vwui# .W UUWWU pjm '.y uU2Zeb5 On* o/ o boni of Aoftrt/M ctfli in a concentretfon mill. Tft# frofh which over* fiowj fh* c*H cortfoins fh* Wodfkh component of fh# C fitx* Bot.ition pruduil which is ixl a physically dosirabW blast furnace material. Tlx* rousted concen trate, or sinter. ix;w in tle form of lumps, is charged into the top of tin* Iteated blast furnace with limt-doix* and oth?r suitable fluxes ami coke for fuel. A blast of air is admitted to tlx* lower |wrt of tlx* furnace to aid combustion and to complete tlx* fonnation of metal lic oxides whkh arr mSucvd to metal by tlx* coke and carbon mmxnide present. Tlic ron-mctallic waste forms a slag with the fluxing materials The blast furnace is tlx*n tapped so that the lead flow's off into kettles nr nxilds. In this form the lead is a scmifinidxd product known as base bullion, con taining silver ami impurities. SpcciRcalk. haw bullion contains small amounts of gold, silver, copper, zinc, antimony, arsenic, bismuth and ot!x*r impurities which must be removed in wltolo or in part by refining to produce a commercial Wad. Krfinini The most widely used refining process is the Parkes process Bn tfiis treatment the lead is first melted and allowed to coni lelow tle freezing point of copper, which crystallizes and is removed by skimming. It then passes to a n*verbrratory or softening furnace whore tlx* temjxTaturr is raised and the molten Wad stirred. A blast of air oxidizes any antimony or a/settic present, both of which impurities harden Wad (lx*nce tlx* term "softening" furnace), and tlx*se oxides arc skimmed off. A continuous softening process for the elimination of antimony atxi arsenic from lead bullion has been perfected which represents more than just a conversion from Iwttch to continuum procedure. In this process, oxidation rate*, many tiirx*s in e\c**s* of tlx*e obtainabW by usual batch softening methods, are realized by tlx* continuous maintenanev of tlx* antimony content of the furnace nx*ta! within a determined optimum range of 0.01-0.05 per cent antimony. The accelerated oxidation rate obt.iinabW in continuous operations per* mits a marked reduction not only in the operational costs of batch method*, but also in space and equip* STAMMRD SPF.CIKICATION *OR PICIXAD A-S.T.M. I^rutlMi B2%49 Qk w Ii I Rc^imwc*> 0T>JinK /yrd* Silvrr, nu^ prr ento Silvn, mm., prr <mt Copper, tout., prf crtX Ccfpjw*. min., prf trot Sdvrr and CVPpprf tojfrthrf. toll.. prf imt Anmlc, nui.. prr (ml Antimony and tn together, max.. prr cent Arsenic, anttmonv, ami tin tnfrtlter, mu. per cent Zinc, mat , pc< <ml Iron, mm . |trf imt RumutK, mat., prf emt Lrad | l.y diflrrrncr), min., pn (ml 011015 00015 00025 0.0015 OOOttS 0 0015 onus 005 99 94 Chrmirwl ls+i' 0020 0 0M2 0060 0.040 Artrf /W 0.002 0 060 0.040 0002 0 001 0 002 0 005 09 00 0002 0001 0 Cto*C 0 025 09 on Crr/*rr l//4 0020 0.060 0.040 0015 0.<*8 0(ht2 0 10 99 65 CWirxtn. Driif< r*- izrd ls**H A" 0-002 0 0025 Crmmam Derifirr- i-~cd ts<l IT* 0002 6.0025 Soft CaW tifn-rtird/W 0.002 664 0.015 0002 0 002 0 IS 99 65 0.015 0 002 OIKS 025 0975 0015 0002 01*2 owe 99 95 *ExpUfuttNy Node: Corrpdinf Wad to <V-ftcn4tum Out has been uxrd for many yr*r* In tlc tra<W In tWxtibe Wad which lau been rrh/ad to high d*-|ficr uf punty Oxmicil Wad has hrrn uml fur man) )r*n ia dr tradr to dcwfibr tlir uniliiilvrrt;nl Wad pradu^rl from Southriam Mis souri orct. Arid Wad It nuW l>> <Wn.< n>pprf to fully rrfiiwd Wad. Cappar Wad t> iru<W lx ailing <*>(>(*? to fully rrm*d W^d. Soft urxWaiKarUad Wad t evd iu lltc ti*W to c x -h o It thr typr U hud produced frvn rr uf Uk Joplin. M-r. district. < aur merrt requirement*. After softening. tlx* lead goes to the desilverizing kettles wlierc small quantities of zinc an* added. Cold and silver art* nxxr soluble in zinc than in lead, and, consequently, any of tliesc metals present in the lead inmxdiatel* least it in lavtir of tin* zinc. .V* zinc is lighter than lead, tlx* ziix: rises to tin* surface and, wlx*n tlx* temperature is lowered. solidifies and Is skimmed. This leaves only a little /.inc remaining as an impurity which is nvidi/cd and skimmed in a reveilx*ratory fumacr. A nw recent developnxmt re moves tlx* zinc as a vapor bv creating a vacuum over tlx* surface of tlx* molten lend Tlx* zinc vapr i< condensed as nx-tul on tlx* cool dome of the vacuum vessel and re-used. Itrfitx*d lead becomes Ofx* *f tlx* purest of tlx* commercial metals through thb treatment and is cast into pips. The Futtinson process, now rarely used, depends upon tlx' fact that wlx-n l*ad is cooled slowly, p^rt of it will solidify and can lx* skimmed off while the silver will remain in tlx* nxdtrn kail left behind. 'i^sr Betts process. rinpViyed in several pljntv including orx* in tlx* United Stjtes, is an elevtrolytic metlxxl advantapeomly used with bullion high in bismuth. The his* nanh is removed and recovered. which It iot the case with tlx* Farkes process. Tlx* Harris process of softmiing and deziixinp l>y the use of molten caustic salts is used in some plants in England, Europe and japan. Tlx* process is designed to remove impurities from molt*n desilverized k*ad by pumpinp it thuxtgh a mi'hirr of nmlttm salts contained in a tank xhme tlx* load kettle. Tlx* metallic impurities react with tlx* clxinicah and are collected in the form of tlxir uvides ovv salts. Tlx* Harris process while sotuxl in llx-orv has txt Ixvn universally adojXcd since in practice it cannot always compete ccorx-mically with tlx* F*rki*> or IVtt process. So iik * on*s, null as tb.xa* of sootlx*astem Missouri, contain Inn little silver fix profit.ihle desilverizing. Therefore tlx* finislx-d pigv, while free from other im* puntim, are ixttid for tlx-ir comparatively high t`ivrr ami copjver content uml arr given tlx* dosii;i .ion "Clxmicu! ` lead txvauw* <*f wide me in tlx* tlx* A C`I Imlustrun in tlx* form of v1x*vi aml pijv Tbit is txi* <HM* of {lx* commercial grade* of pip lead vilahlr to the consumer. Tlx'sc prades art* described In the accompanying table of tlx* American SoHcty for Testinp Mattriah specification for the various grades of pig lead. Scrap u Important Sourer of Lend An important source of lead each year is scrap or sccoixlary lead as it is nvorc formally known. In 195$, in tlx* United Stat<*s, approximately 455,000 tons of lead were produced from secondary sources accounting for more than a third of all the lead consumed by American industry in that year. The chief scxirce of lead scrap Is from automobile storxpe batteries which contain somewhere b*twern 20 and 25 lb. of lead a piece, Tle bulk of this lead Is recovered after an avtTage service life of about 26 montlis. Additxnud sourevs f<x lead scrap include such items as lead slx*atlx*d cahk*. pipe aikl sheet, solder, railroad U*ariiigs, type metals aixl lead drosses. SoootKLiry lead is recl.iiiix*d by 6re refining methods in refiner*^ usually ilnntivl exclusively to tlx* handling of xviHslin leatl aixl lead a Urns. A comparatively small percentage is also rrfitxd at primary refineries. Much of tlx* vcotxlurv lead produi'cd is s*dd as lead alloy, particularly lead from rxvlainxd Ivatteries and cable slaathing which contain small prriviitagos of an timony aixl otlxT metals. Tlx* Ixitk of tlx* secondary lead recoveml containing antimony is rc->nld to hattery manufacturers. Secondary had containing tin is most often rc-uvd in the manufacture of solder, bearing metals and otlx < V ad-tin alloys. By applying proper refining technique. soft lead can be produced from wcondary soureev to inert primary lead specifications. Figs of lead and antii.xmial lead mu.illv weitih abotit 100 II). each, while ingots of lend or its nflovt may havr almost am- dt-siretl w*ight a ik ! sliajx' from the suuli 3- to 5-Ih cakes to lx* melted in portable gasoline furnaces to 100-lh. cvliixlrical billets to fit extrusion presses. Lead and Lrad Alloy Product* In semi-fabricated ami fabricated form, a variety of lead and lead alloy poxliRtv arr available. Examples arc: CoU`f>g rtfin*d l+od into p*gi  ^i" LIA22867 i^U. 1. F.ttnxWd - ptpr. rod. wtrr, ribbon, traps, brods. vrdjfr k**d. tpreul *Kapr 2. Rolled -- d1, fid. strip liLhki fur drawing, cUmpin* and ipmning. l*Unl of \*n<ma diapr* 3. Cast - sand ur dtr-rart (Ktjtily nr prrtsure) 4- Ox-mkal ConijxHirxU - mule*. * sulphate*. rlirufnatrt, organic OHiijamritU. ulKalrs, M.**ta*rt etc. 5 Ohrf -- X(r<llk pcmUl, WI1>4. 1m< Lead and iU alloys ran !k * fabricated by almost all commercial process*-*. It can, far instance, Ik * extrud ed. drawn, rolled, cast, stamped, spun. and can be applied as a coating to other metals eitlxT by lxit- dipping, ch-ctruplating or spraying. Thick layer* of lead can be bomb'd to steel or otlxi metals for greater strength. Joints may Ik * nuule by soft *oWrring or welding. The pmiK-rtu*) of lead and most of it' alloys arr quite difi<Tcut from tbosr* of otlxi- oxtals. xit this very difference iiiake* lead p'culi.ir!\ suitable for many ap plications wlx're other nxi.ih would not Ik * practical. dustry is a pretty Imporia^t c*jrtomcr. In a recent year alxxit 1,124,000 tx-t tun* of lead ore and concen trates w it t shipped fn a total of 20,000 railroad car* within the birder* of this country. More than 8,000 ear* shipped ov er 447,(WO tom of lead-containing red* does ami scrap. Alxxit 757,000 ton* of lead bullion and pig lead were shipped in 14.500 car*. Thu* American railroad* in one year iivd alxm* 42,500 railroad cars to transport more tluin 2.325,000 ton* of lead and lead* containing material* to and from lead smehen and refineries. Tltesr large tonnages are still only a part of the total lead slvipped by rail each year. A major source of rknix-stic supply of lead comes from foreign source* and the hulk of this tonnage. 555.000 tons in 1951, upon arrival at American ports is shipped by rail. Secondary lead, tlx* thi.vl source of supply amounting to 415,000 tons in 195V is also shipped hy aik though to a lessee extent tlian tlx* primary sources. TIk - iiv of tlx* railroads hy the lead industry* dor* tmt stop with tlie raw material. Tig lead, and the huts* doth of product* nude from lead, such as tlie storage betters whkh contains approximately 20 lb. of lead, arc also major uvi* of rail freight. Breovs* of Ht tow me'finp po<nf, lead it ttodily cost into pfOChcoUy any p* On tlo otlxi lund, it is often possible to gain Mime useful property of lead in cai wlwrc lead may not at first seem suitable. if t!x*v lifb rents*) art* dearly rccogriTcd. For imtaw-c. xbgh* d sign changes or changes in manufacturing hiltnnpie may r.ake it jvrssi blr to uv* lead with greater sativfactinn in plaee of a metal with quite different ih.iratterixtic*. In get h i a I. lead mx! its alloy* base high resistance to corrosion, high sjx-i ifc gravity. are mjnjur.itivelv soft, have a low melting piint are easily fabricated TIm-v have lew ehxtrieal conductivity and tensile strength and a relatively high etr-fheient of thefird expansion. lloweser. tfm* projwrties can |w varied within quit*' a wide range !> jnduiom iim> of alloying elements. For iiixtamv, strength ami hardix-ss of ordinary lend can In* multiplied many times or un iting point greatly reduci-d by alloying. la-ad harden**! and stii ngthenetl with small amounts of tin, antimony and arsenic. or <*vi*n smaller percent age* of tin* allaliiM* eaith m< tals f> a standard antifriction nutenal lor many tvjx-s of hearings. and tlx* larg-4 (tiiisuitH,f of had for this jxirpiv- is tin* rail roads. Tin* standard K \ It solid hearing assemhh eontaint alsotit h lh of lead. Incider'ally. shaking alxxit railmadx. the had in la*ad Rorrvr* Ample TIh t c has U-vn considerable discussion about U. S. h ail revrvis in n-vent years. To the uninitiated, fig ures rrpiesenting lead nvrvis can he misinterpreted v*rv easily. For instance, in 1947, liearings before the ''ulKommitli't* on Iu\<*stigjti<>n of Natirmal flesources erf tV Senate Omimittiv on Public IarxU were published. In :1h *m- baiiugs, repM*s<*iitatiscs of tlie U. S. Bureau o! and tlie l*. S G<*<'hgical Survey estimati'd r<no\cralth- h .ul contaitK-d in rt*sTVi*N in tlie ground at .ihmt fi.V'ni'oft tn:i\ in l&M, or atxiut 15 timr* the asifuge 19 > >-1944 rale of prodnctKm. Tlw lay irvin. given this wt of f-ts, would reach the cuiK'lusion tlut by 1959 tlirrr would be no more lead h*ft in tlx* 1* S to lx* mirxxl Ihmewr. in the report of tlx* President'* Matmah Policy (aimmission. publislxtl in June*. 1952, rrscrvm are <-\timated at about 7.(K*Mt00 tom in 1950, or alxmt 10 tux*s 1950 produc tion Thus estifiutevl rrvrvr* were somewhat higler in p)50 tlun in PHI despite tlie fait tlut iwariv 2,500.000 tons of lead li.ul lx*cn tnirx*! fioni Vnitrd State* imix-s iu tlx' intiT'.'ening years. Both n*ports admit tlut tlx' r-ser*r figures given arc minima. Tliis clearly indicah-s tlx* <Uner of using revive figures a* of any particular date a* a guidr* to tlie life of the reserve* hvaiiw they (atmot of rx*ci*svity take into account the rx-w rev-m* ojxixil up each year. Also, a mining company will block ovit it* reserve* for only a few years alx'ad of its. actual mining operation* Ixvause of tlx* rvomimlc factors involved. The g<ixTal pra<-tice Is to fmd thnxigh dr*eh>pment work erxxigh revenvs each year to repla<e tlie anxxmt cs- (meted. Kvp<*rieixc ha* slxiwn that reserves will lie ade<juate to take care of tlx- Win M s nessh fix h ad for many years to eotne and any ti-nqxsrary shortage tliat has dev elop'd Iu-. Ixs'n tlx- n*Mih of nimomic maladjustnvnt and artificial itiutmls (airrentlylead Is plentiful .o h I tlx-fr is nothing to nxlicate that it will not remain sa 0