S E C O N D only to th e railroads, steel m ills in th e U n ited S tates use m ore pow er in d u strial trucks th an an y o th er group.
H ig h in th e list also are th e m etalw orking a n d m etal-consum ing industries such as those d ev o ted to m achining, stam ping, forging; foundries, aircraft, motors, trucks; p a p e r, chem icals, food packing an d ru b b e r. A ll h ave m a d e v ital con
trib u tio n s to th e w a r effort, an d all de
p e n d on p o w er trucks a n d o th er m odem eq u ip m e n t fo r conveying a n d handling ra w m a te ria l an d finished products.
P ow er trucks h av e w on w idespread recognition as im p o rtan t factors in fast, econom ical a n d safe pro d u ctio n . O ne of th e reasons fo r this is th a t th ey conserve m anpow er; a n d w h a t is m ore im portant in m an y industries, they accom plish work
112 / T E E L
Fig. 5— T h e tw o tines o f th is fo rk tru ck are b ein g used to h andle te n coils o f w ire a t a tim e , greatly reducing
tim e a n d cost o f unloading
Fig. 6— B lack sheets and tin plate stra p p ed to skids are h a n d led a n d tiered easily, e ffectively reducing shipping
an d storage costs at b o th m ill a n d fabricating p la n t
Fig. 7— S a fe ty clam ping a tta ch m en t is b u ilt in to fra m e to ho ld loose m aterial d u ring h a n d lin g operations
Fig. 8— O ne o f first p o w er tru cks w as a u n it o f th is ty p e e m p lo y e d in charging annealing fu rn a ce w ith m alleable iron castings in pots. R u b b e r tires w ith sta n d tem p era tu res u p to 700 d egrees Fahr., p erm it loading and u n
loading furnace w h ile hot May 21, 1945
that is considered h azard o u s an d rep ellen t when done m anually.
T h e g reatest ad v an ce in developm ent of p o w er trucks o ccu rred in th e years betw een th e o u tb reak of W o rld W a r I and th e b eg in n in g of th e p re s e n t struggle.
T hey w ere w ell estab lish ed as indispens
able eq u ip m e n t in m an y industries, ready to assist in acceleratin g m ass pro d u ctio n of goods a t th e o u tb reak o f this w ar.
Im provem ents h av e b e e n m a d e in re
cent years, m ainly in enlarging p o w er plant an d capacity, a n d to a n im p o rtan t extent in desig n of attach m en ts to a d a p t them to m ore uses. B u t basically they are th e sam e m achines w h ich w e re a t work in m an y industries in 1940, and which w e re o rd e re d in large num bers for n e w p lan ts d e v o ted to p ro d u ctio n of arm ament.
D em an d fo r th em exp an d ed m uch fa s te r th a n th e y could b e b u ilt. L ike m ach in e tools a n d o th e r essentials, th ey w ere co n tro lled by d o u b le-b arreled p ri
orities; steel fo r th e ir construction could be o b tain ed only on g overnm ent order;
an d th e ir d istribution w as lim ited to those com panies w orking on essential re q u ire m ents.
T h e su b ject of m aterials h an d lin g has been stu d ie d intensively, an d if recen t experience is a n y indicator, th e use of p o w er trucks w ill b e universally accep ted p ractice in p o stw ar m an u factu rin g .
I t is not difficult to discern th e reason w hy th e steel ind u stry is one of th e la rg est users of such trucks. T h e ind u stry is a vast m echanism fo r h an d lin g m aterials
— in m ining, tran sp o rtatio n , processing, a n d shipping— em ploying m ore e q u ip
m e n t of a diverse ch a ra c te r in th ese operations th a n any o th er group.
T h e steel ind u stry ’s evolution in m achines an d m eth o d has ab o lish ed b a c k breaking, d angerous m an u a l labor. As every one know s, it has c o n trib u te d in large m easure to establishing this n atio n ’s h ig h sta n d a rd of living. B u t n o t so g en erally u n d ersto o d is th e fa c t th a t if it h a d n o t achieved these results befo re th is w ar, th e fa te o f th e w o rld m ig h t h av e b een different, fo r it n o t only su p p lied th is co u n try ’s req u irem en ts of all-im p o rtan t w ar m etal, b u t also m o st of those of o u r allies.
Som e id e a of steel as a m aterials- h an d lin g in d u stry m ay b e g ain ed from figures issued recen tly by the A m erican Iro n a n d S teel In stitu te, w h ich show th a t 5 tons of raw m aterials are consum ed
Fig. 3— E xtra h ea vy d u ty ram tru ck carries 25,000- p o u n d coil. Four w h eels arranged in pairs across th e front, each pair p iv o te d to conform to flo o r irregulari
ties a n d d istrib u te load evenly. A ll fo u r w h eels h ave brakes. O ne w h e e l in each pair is d riv e n th ro u g h roller
chain fr o m m otor-driven differential bearing axle
Fig. 4— T h is tru ck has cradle w ith rollers on b a ck a n d ' b o tto m extension p erm ittin g u n it to u p e n d coils. E x te n sion on other side is in fo r m o f tw o forks. U nit can p ick u p coils fro m either horizontal or vertical position, ro
tate th e m 90 degrees a n d d ep o sit th e m in reverse posi
tion or discharge th e m a t th e side. C radle is tilte d b a ck
w a rd w h e n traveling to p re v e n t coil fro m rolling off Fig. 1— H u g e “p o w er w agons” o f th is ty p e are one o f
latest innovations in steel m ills w h ere th eir 156-inch pla tfo rm is e q u ip p e d w ith six sets o f endless conveyor chains tltat can b e d riven in eith er direction to load, straighten or discharge th ree or fo u r large coils, d e p e n d ing u p o n diam eter. R a ted capacity is 50,000 pounds.
M achine p ro ved less costly to operate th a n road tru ck or industrial railw ay
Fig. 2— C losing doors o f d u m p or hopper ty p e ore cars in L a k e Superior district is to u g h job in cold w eather w hen ice freezes m echanism s. B u t n o w th e special pow er truck sh o w n e q u ip p e d w ith a m echanical connection to th e car m ech a n ism w in d s u p b o tto m gates on 515
cars in
Fig. 9— B attery b eh in d operator counterbalances h ea vy loads on
th is ram truck
Fig. 10— R am tru ck is d riven and steered b y both th e fro n t and
rear w h eels
T o tal ... 28,798,826 In mills such as those d ev o ted to pro
duction of heavy, com pact tonnages, and in th e ir w arehouses and shipping de
p artm en ts especially, p o w er trucks have d em o n strated th eir p o w er a n d stam ina.
V irtually all types are in service, in
cluding those w ith low -lift a n d high-lift platform s; cranes; com bination platform s a n d cranes; fork trucks w ith various at
tachm ents for h a n d lin g v aried classes of m aterial; th e sim ple load carrier, with larg er p latfo rm area; th e tra c to r fo r haul
in g trains of h a n d or po w er-lo ad ed trucks.
In re c e n t years, som e unusually large trucks h ave b e e n b u ilt, w ith special m echanism s fo r m u ltip le loads of strip steel in coils.
C apacities of th e m achines range from 1 0 0 0 to 60,000 pounds, b u t th e average of those in th e m ills is 6000 to 1 2 ,0 0 0 p ounds. L ow -lift p latfo rm trucks lift th e ir loads 3 to 6 inches, w hile high-lift p latfo rm an d fork ty p e trucks elevate loads to h e ig h t of 117 inches. Crane trucks h av e telescoping boom s extending 12 to 19 feet.
E x c e p t fo r th e b atteries in the all
electric trucks, a n d th e controls arid rub
b e r tires, th e trucks are practically all steel; th e bodies b e in g b u ilt of heavy
( Please tu rn to Page 144) fo r every ton of steel produced. T he
n u m b er o f freig h t cars th a t w ould be n eed ed to ho ld all its incom ing m aterials a n d outgoing products as in 1944 w ould re a c h 2V4 tim es aro u n d th e e a rth a t th e e q u ato r. In every 24 hours th e ind u stry as an average receives:
317.000 n e t tons of iron ore 249.000 n e t tons of coal 128.000 n e t tons of scrap
80,200 n e t tons of limestone
25,000 n e t tons of miscellaneous m aterials 5,779,000 gallons of fuel oil
621,300 gallons of ta r and pitch
T hese m aterials are enough to load 16,000 fre ig h t cars, a train 133 miles long.
I n every 24 hours, th e in d u stry ships steel in the follow ing tonnages to these consum ers:
Consum er Ne t Ions
F or direct w ar purposes ... 58,548 To the railroads ... 15,954 C onstruction ... 12,258 Containers ... 10,925 M achinery and tools ... 6,645 Pressing, stam ping an d fo rm in g . . 7,930 A griculture ... 3,044 Oil, gas and m i n i n g ... 4,426 C onverting, export and processing 44,962 Jobbers and distributors ... 21,410 M iscellaneous consumers ... 12,180
T o tal ... 198,282
T his tonnage w o u ld load 4406 fre ig h t cars, a train 36 m iles long. M ore than 41 p e r c e n t of th e in d u stry ’s o u tp u t of finished steel in re c e n t years has b e e n in th e flat-rolled classification, as for ex
am p le in 1944:
Product
T in and tem e p late . ...
Strip ...
Sheets ...
Black p late ...
Sheared and universal p la te . .
OX Y ACETYLEN E p ressu re w elding may b e fully or p artially m echanized.
Specimens are b u tte d u n d e r nom inal pressure, h e a te d b y m eans of m u ltip le small oxyacetylene flam es to a tem p era
ture o f a b o u t 1200 degrees C en t, an d upset to a co n tro lled d eg ree. Tire p ro c ess possesses m any special advantages, among w hich are a d ap ta b ility to high- carbon an d alloy steels, w hich are w e ld ed w ith difficulty b y fusion w elding methods; sm oothness and uniform ity of the com p leted w eld; sh o rt w eld in g tim e;
and relativ ely low u n it cost. Physical properties of th ese p ressu re w elds are excellent.
O xyacetylene p ressu re w eld in g differs from p ractically every o th e r cu rre n t welding process in th a t th e w eld is m ade not in th e liq u id p h ase b u t b y coales
cence of grains across tire w eld in te r
face a t subfusion tem p eratu res u n d e r the influence o f co n tro lled tem p e ra tu re and pressure. T h e w eld is accom plished by abu ttin g th e clean sq u are faces of the two sections to b e w eld ed u n d e r moderate pressu re, an d h e atin g th e w eld zone by one o r m o re oxyacetylene flames to a uniform te m p e ra tu re o f a b o u t 1 2 0 0 to 1250 degrees C ent. (2192 to 2282 degrees Faltr.) u n til u p settin g a t th e
joint occurs. T h e com pleted joint has a definite b u lg e or u p se t a t th e w eld, varying in h eig h t w ith th e thickness o f th e m etal w elded. T h e b u lg e is characterized b y sm ooth, w ell-ro u n d ed fillets. T h e process is ideally a d a p te d to sem iautom atic o r fully au to m atic o p eration an d th u s is cap ab le of a hig h d e g ree of uniform ity. F ig. 1 illustrates a group of p ressu re w elds in 1 an d 114- inch d iam eter b a r stock show ing th e gen eral ap p earan ce o f w elds m ade by this m ethod.
A p p aratu s fo r p ressu re w eld in g com prises e q u ip m en t fo r app ly in g en d p re s
sure, suitable w eld in g h ead s designed to p rovide uniform a n d co n tro lled heating, an d necessary indicating an d m easuring devices fo r reg u latin g th e process th ro u g h o u t its cycle of operation.
Pressure E q u ip m en t: T h e ty p e of p ressure eq u ip m e n t d ep en d s alm ost en
tirely on th e shape of th e specim en a n d th e location of th e w eld. Som e operations req u ire ra th e r com plex e q u ip m ent, w h ereas fo r others a sim ple press is en tirely suitable. F o r joining long m em bers such as railroad rails a n d ov er
lan d p ip e, presses e q u ip p e d w ith side clam ping jaws are necessary, a n d sev
eral different types of th ese clam ps h av e
Fig. 1— O xyacetylene w eld s in group of 1 a nd VA-inch d ia m eter bars. N o te general condition o f upset zone a nd clean sm o o th condition a fter w eld in g
*
FiS- 2— M ultiple fla m e heads fo r pressure w eld in g o f railroad rails. Flam es directed do w n w a rd on to p surface o f rail are o f uniform size, w hereas fla m es directed against side, w e b and base o f rail are proportioned to (hickness of
section against w hich th e y im p in g e