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Towided by P a id Revere in ISO I

Executive Offices: 230 P ark Ave., N ew Y ork 17, N . Y.

Revere has made over 2,000,000 rockets out of electric welded tube tested up to 6,000 lbs.

per square inch.

I R O N a n d S T E E L P R O D U C T I O N

as the first. Instead of depending on a material having a high thermal conduc­

tivity to transmit a large quantity of heat, a thin wall section of material having lower conductivity high storage properties was used. In batch-type op­

erations this storage factor made the recuperator a 'thermal fly-wheel’ that stored heat from one cycle and gave it air through the recuperator under suffi­

cient pressure to operate modern burn­

ers efficiently.”

M etallurgists Concerned with Control of M elting Reactions

J. S. Marsh, engineer, stocks of virgin materials through care­

ful selection and segregation of alloy scrap and through controlled melting.

Controlled melting presupposes knowl­

edge of the reactions of the alloying elements in the presence of steel and slag; and we are indebted heavily to the chemically minded metallurgists for the information amassed to date. For example, their data prove that • the be­

havior of the oxidizable elements, such as chromium, manganese, and phosphorus is similar; high residuals are favored by high temperature, low metal oxy­

gen (i.e., high carbon), low slag vol­

ume, and other items, such as slag basicity in the basic process.

"Knowledge of melting reactions is equally applicable to the problem of making steels of low contents of alloy­

ing elements such as nickel, copper, mo­

lybdenum, chromium, manganese, and phosphorus. Since the first three ele­

ments are not oxidizable in the sense of the behavior of the last three, it follows that they can be controlled best by dilu­

tion. The oxidizable elements, however, can be minimized by inverting the steps listed for high recovery; thus elimination of chromium, manganese, and phos­

phorus is favored by low temperature, high metal oxygen, and high slag vol­

ume.

“The growing knowledge of steel- melting reactions is making it increasing­

ly possible to separate probables from

improbables in on-paper furnace prac­

tices.” severe manpower shortages, and drastic scarcities of many raw materials, the in­ quality and particularly surface condi­

tion and yield on all grades of steel has been a factor seldom taken into adequate consideration until such huge tonnages of ‘quality steels’ afforded the oppor­

tunity to follow through in minute de­

tail the effects heretofore considered trivial. In no place in the steel plant heated. Continuous research on at­

mospheres in both open-fired heat­

ing furnaces and in furnaces with special protective atmospheres has suc­

ceeded in establishing many of the laws of cause and effect which govern the chemical changes caused by heating in

gaseous atmospheres (scaling and de- carburization are two of the principal results).

“Engineering problems involved in applying these laws are now being solved

“Development of furnaces and instru­

ments for furnace atmosphere control is

“These developments, spurred by ex­

perience being gained in these war years, will include control of open furnaces by supervised instrumentation, atmosphere furnaces for heat-treating, annealing, and for ‘skin recovery’ of carbon lost in forming processes, and determination of the proper uses of salt treatments and of induction heating for surface control.”

Temperature M easurem ent of Liquid S teel Show s Progress

rate and unreliable. Recently, however, independent research by several differ­

ent steel plants and co-operating instru­

ment manufacturers has resulted in the development of equipment which gives every indication of fulfilling the pressing need for quantitatively accurate instru­

mental means of determining molten steel temperatures.

“One of the more promising inventions is that by U. S. Steel Corp. for modifi­

cation of the Collins-Oseland open-end tube using a photoelectric (photronic) cell as the radiation sensitive unit for converting the radiant energy of the bath to electrical energy for recording pur­

poses. Another adaptation of the Col­

lins-Oseland tube which is being ac­

tively developed involves the use of a high-speed radiation sensitive thermo­

pile together with suitable recording equipment for reading the output volt­

ages; this equipment, when perfected, will favor a high degree of speed and accuracy, and a minimum maintenance cost.

“In one basic electric shop each fur­

nace has been equipped with a

quick-260 / T E E L

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< A R. B O L O Y

tT R A D E da r> p M A R KM A R K

C A R B O IO Y C O M P A N Y , INC. • U141 E. EIGHT MILE BLVD. • DETROIT 32, M IC H IG A N

C H „ „ . . Ckvalond HdUiton . to t A n,... « - > - • " ~ * "■ '> * '-'* ■ " " ' - t '

January 1. 1945

261

I R O N a n d S T E E L P R O D U C T I O N

immersion pyrometer consisting of a platinum, platinuni-rhodium thermocou­

tentiometer type recording instrument.

"To the furnace operator these devel­

opments signify an opportunity to im­

prove steel quality and furnace life, and reduce refractories costs; to the metal­

lurgist and the research engineer they afford for the first time adequate means to study and control tire complex physi­

cal chemistry reactions involved in the steelmaking process.”

R ecorded Flam e Temperatures Serve A s V aluable Guide maintenance, repairs, scheduling, charg­

ing, working, tapping, and teeming have been worked out with precision and all avoidable delays and interruptions have been cut down approaching an irreduci­

tion. Combustion engineers are study­

ing flame conditions as a means of con­

trolling combustion in order to obtam better flame temperatures throughout the furnace for the various stages of the heat. This has resulted in locating the maximum flame temperatures immedi­

ately above the bath on the incoming end furnace and only represented the condi­

tions which existed at the time. Also and slag temperature throughout the furnace operation. This procedure not only gives more information on which to evaluate the flame conditions but pro­

vides a valuable guide for the furnace operator in regulating the combustion air, atomizing steam, and liquid fuel.

“Effects of flame conditions, tempera­

tures, and heat-head above the open- cut down production. Bath temperature is a new tool to increase not only quality but also production and efficiency.”

Serious Alloy Contamination

main relatively uncontaminated, it would appear that, with any reasonable volume of carbon steel from here out, we need not fear serious alloy contamination.

“Should steel production fall back to 50,000,000 tons and scrap separation cease, the producers of carbon steel

All-Scrap Open-Hearth H eats Afford Lower Mix Cost fired furnaces of conventional design.

Carbon in tire form of graphite and pe­ spiegel whenever they are available.

The silicon added to the bath to keep the carbon from too rapid oxidation is obtained from silicon sheet scrap averag­

ing about 3 per cent silicon. temperature of 375 degrees Fahr.

“Results are comparable with those obtained from conventional pig-scrap charges in the same shop. This practice is no cure-all for the troubles normally encountered in open-hearth operation;

about the same percentage of soft metals, raw slags which have to be shaped up, and time-consuming high melts will be encountered. It does, however, with proper supervision and metallurgical control give as good quality and yield those for normal peace-time require­

ments. This has been helpful in

obtain-262 / T E E L

Manufacturer of: Universal Turret Machines • AutomaticThread

M A C H I N E C O M P A N Y

SPRINGFIELD, VERMONT, U. S.A.

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