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Glossary of Steel
Industry Terms
                         

Agglomerating Processes
Fine particles of
limestone (flux) and iron ore are difficult to handle and transport
because of dusting and decomposition, so the powdery material is
usually processed into larger pieces. The raw material's properties
determine the technique that mills use.
- Sinter.
Baked particles that stick together
in roughly one-inch chunks. Normally used for iron ore dust
collected from the blast furnaces.
- Pellets.
Iron ore or limestone particles
rolled into little balls in a balling drum and then hardened by
heat.
- Briquettes.
Small lumps formed by pressing
material together. Hot Iron Briquetting (HBI) is a concentrated
iron ore substitute for scrap for use in electric
furnaces.
AISI (The American Iron
and Steel Institute) An association of North American companies
that mine iron ore and produce steel products. There are 50 member
companies and over 100 associate members, which include customers
who distribute, process or consume steel. The Institute has
reorganized into a North American steel trade association, which
represents the interests of Canada, Mexico and the United
States.
Alloying Element Any
metallic element added during the making of steel for the purpose of
increasing corrosion resistance, hardness, or strength. The metals
used most commonly as alloying elements in stainless steel include
chromium, nickel, and molybdenum.
Alloy Steel An
iron-based mixture is considered to be an alloy steel when manganese
is greater than 1.65%, silicon over 0.5%, copper above 0.6%, or
other minimum quantity of alloying elements such as chromium,
nickel, molybdenum, or tungsten. An enormous variety of distinct
properties can be created for the steel by substituting these
elements in the recipe.
Alloy Surcharge The
addition to the producer's selling price included in order to offset
raw material cost increases caused by higher alloy
prices.
Annealing A heat or
thermal treatment process by which a previously cold-rolled steel
coil is made more suitable for forming and bending. The steel sheet
is heated to a designated temperature for a sufficient amount of
time and then cooled. The bonds between the grains of the metal are
stretched when a coil is cold rolled, leaving the steel brittle and
breakable. Annealing "recrystallizes" the grain structure of steel
by allowing for new bonds to be formed at the high temperature.
There are two ways to anneal cold-rolled steel coils - batch and
continuous.
- (1)
Batch (Box).
Three to four coils are stacked on top of each
other, and a cover is placed on top. For up to three days, the
steel is heated in a non-oxygen atmosphere (so it will not rust)
and slowly cooled.
- (2) Continuous.
Normally part of a coating line,
the steel is uncoiled and run through a series of vertical loops
within a heater: The temperature and cooling rates are controlled
to obtain the desired mechanical properties for the
steel.
Argon-Oxygen
Decarburization (AOD) Process for further refinement of
stainless steel through reduction of carbon content. The amount of
carbon in stainless steel must be lower than that in carbon steel or
lower alloy steel (i.e., steel with alloying element content below
5%). While electric arc furnaces (EAF) are the conventional means of
melting and refining stainless steel, AOD is an economical
supplement, as operating time is shorter and temperatures are lower
than in EAF steelmaking. Additionally, using AOD for refining
stainless steel increases the availability of the EAF for melting
purposes. Molten, unrefined steel is transferred from the EAF into a
separate vessel. A mixture of argon and oxygen is blown from the
bottom of the vessel through the melted steel. Cleaning agents are
added to the vessel along with these gases to eliminate impurities,
while the oxygen combines with carbon in the unrefined steel to
reduce the carbon level. The presence of argon enhances the affinity
of carbon for oxygen and thus facilitates the removal of
carbon.
Attrition A natural
reduction in work force as a result of resignations, retirements or
death. Most unionized companies cannot unilaterally reduce their
employment levels to cut costs, so management must rely on attrition
to provide openings that they, in turn, do not fill. Because the
median ages of work forces at the integrated mills may be more than
50, an increasing number of retirements may provide these companies
with added flexibility to improve their competitiveness.
Austenitic The
largest category of stainless steel, accounting for about 70% of all
production. The austenitic class offers the most resistance to
corrosion in the stainless group because of its substantial nickel
content and higher levels of chromium. Austenitic stainless steels
are hardened and strengthened through cold working (changing the
structure and shape of steel by applying stress at low temperature)
instead of by heat treatment. Ductility (ability to change shape
without fracture) is exceptional for the austenitic stainless
steels. Excellent weldability and superior performance in very low
temperature services are additional features of this class.
Applications include cooking utensils, food processing equipment,
exterior architecture, equipment for the chemical industry, truck
trailers, and kitchen sinks. The two most common grades are type 304
(the most widely specified stainless steel, providing corrosion
resistance in numerous standard services) and type 316 (similar to
304 with molybdenum added to increase opposition to various forms of
deterioration).
Auto Stamping
Plant A facility that presses a steel
blank into the desired form of a car door or hood, for example, with
a powerful die (pattern). The steel used must be ductile (malleable)
enough to bend into shape without breaking.
Automatic Gauge Control
Using hydraulic roll force systems, steelmakers have the ability
to control precisely their steel sheet's gauge (thickness) while it
is traveling at more than 50 miles per hour through the cold mill.
Using feedback or feed-forward systems, a computer's gap sensor
adjusts the distance between the reduction rolls of the mill 50-60
times per second. These adjustments prevent the processing of any
off-gauge steel sheet. Go back to the top

Bake Hardenable
Steel A cold-rolled, low-carbon sheet steel used for automotive
body panel applications. Because of the steel's special processing,
it has good stamping and strength characteristics and, after paint
is baked on, improved dent resistance.
Basic Oxygen Furnace
(BOF) A pear-shaped furnace, lined with refractory bricks, that
refines molten iron from the blast furnace and scrap into steel. Up
to 30% of the charge into the BOF can be scrap, with hot metal
accounting for the rest. BOFS, which can refine a heat (batch) of
steel in less than 45 minutes, replaced open-hearth furnaces in the
1950s, which required five to six hours to process the metal. The
BOF's rapid operation, lower cost.and ease of control give it a
distinct advantage over previous methods. Scrap is dumped into the
furnace vessel, followed by the hot metal from the blast furnace. A
lance is lowered from above, through which blows a high-pressure
stream of oxygen to cause chemical reactions that separate
impurities as fumes or slag. Once refined, the liquid steel and slag
are poured into separate containers.
Bars Long steel
products that are rolled from billets. Merchant bar and reinforcing
bar (rebar) are two common categories of bars, where merchants
include rounds, flats, angles, squares, and channels that are used
by fabricators to manufacture a wide variety of products such as
furniture, stair railings and farm equipment. Rebar is used to
strengthen concrete in highways, bridges and buildings (see Sheet
Steel).
Billet A
semi-finished steel form that is used for "long" products: bars,
channels or other structural shapes. A billet is different from a
slab because of its outer dimensions; billets are normally two to
seven inches square, while slabs are 30-80 inches wide and two to
ten inches thick. Both shapes are generally continually cast, but
they may differ greatly in their chemistry.
Black Plate
Cold-reduced sheet steel, 12-32 inches wide, that serves as the
substrate (raw material) to be coated in the tin mill.
Blast Furnace A
towering cylinder lined with heat-resistant (refractory) bricks used
by integrated steel mills to smelt iron from its ore. Its name comes
from the "blast" of hot air and gases forced up through the iron
ore, coke and limestone that load the furnace. Under extreme heat,
chemical reactions among the ingredients release the liquid iron
from the ore. The blast of air burns the coke, and limestone reacts
with the impurities in the ore to form a molten slag. The hot metal
collects in the bottom of the furnace. Once fired up, the blast
furnace operates continuously until it needs to be relined seven to
ten years later.
Blanking An early
step in preparing flat-rolled steel for use by an end user. A blank
is a section of sheet that has the same outer dimensions as a
specified part (such as a car door or hood) but that has not yet
been stamped. Steel processors may offer blanking for their
customers to reduce their labor and transportation costs; excess
steel can be trimmed prior to shipment.
Bloom A
semi-finished steel form whose rectangular cross section is more
than eight inches. This large cast steel shape is broken down in the
mill to produce the familiar 1-beams, H-beams and sheet piling.
Blooms are also part of the high quality bar manufacturing process:
Reduction of a bloom to a much smaller cross-section can improve the
quality of the metal.
Breakout An accident
caused by the failure of the walls of the hearth of the blast
furnace resulting in liquid iron or slag (or both) flowing
uncontrolled out of the blast furnace.
Burr The very subtle
ridge on the edge of strip steel left by cutting operations such as
slitting, trimming, shearing, or blanking. For example, as a steel
processor trims the sides of the sheet steel parallel or cuts a
sheet of steel into strips, its edges will bend with the direction
of the cut (see Edge Rolling).
Busheling Steel
scrap consisting of sheet clips and Stampings from metal production.
The term arose from practice of collecting the material in bushel
baskets through World War 11.
Butt-Weld Pipe The
standard pipe used in plumbing. Heated skelp is passed continuously
through welding rolls, which form the tube and squeeze the hot edges
together to make a solid weld. Go back to the top

Capacity Normal
ability to produce steel in a given period. This rating should
include maintenance requirements, but because such service is
scheduled to match the machinery's needs (not the calendar's), a
mill might run at more than 100% of capacity one month and then fall
well below rated capacity as maintenance is performed.
- Engineered
Capacity. The theoretical volume of
a mill, given its constraints of raw material supply and normal
working speed.
- "True"
Capacity. Volume at full
utilization, allowing for the maintenance of equipment and
reflecting current material constraints. (Bottlenecks of supply
and distribution can change over time - capacity will expand or
reduce.)
Casing Casing is the
structural retainer for the walls of oil and gas wells and accounts
for 75% (by weight) of OCTG shipments. Casing is used to prevent
contamination of both the surrounding water table and the well
itself. Casing lasts the life of a well and is not usually removed
when a well is closed.
Cast Iron (See
Pig Iron)
Charge The act of
loading material into a vessel. For example, iron ore, coke and
limestone are charged into a Blast Furnace; a Basic Oxygen Furnace
is charged with scrap and hot metal.
Chromium (Cr) An
alloying element that is the essential stainless steel raw material
for confeffing corrosion resistance. A film that naturally forms on
the surface of stainless steel self-repairs in the presence of
oxygen if the steel is damaged mechanically or chemically and thus
prevents corrosion from occurring.
Circored A gas-based
process developed by Lurgi Metallurgie in Germany to produce DRI or
HBI (see Direct Reduced Iron and Hot Briquetted Iron). The
two-stage method yields fines with a 93% iron content. Iron ore
fines pass first through a circulating fluidized-bed reactor, and
subsequently through a bubbling bed fluidized-bed
reactor.
Cladding Method of
applying a stainless steel coating to carbon steel or lower alloy
steel (i.e., steel with alloying element content below 5%). Used to
increase corrosion resistance at lower initial cost than exclusive
use of stainless steel. Methods: (1) welding stainless steel onto
carbon steel, (2) pouring melted stainless steel around a solid
carbon steel slab in a mold, or (3) placing a slab of carbon steel
between two plates of stainless steel and bonding them by rolling at
high temperature on a plate mill.
Coils Steel sheet
that has been wound. A slab, once rolled in a hot-strip mill, is
more than one-quarter mile long; coils are the most efficient way to
store and transport sheet steel.
Coke The basic fuel
consumed in blast furnaces in the smelting of iron. Coke is a
processed form of coal. About 1,000 pounds of coke are needed to
process a ton of pig iron, an amount which represents more than 50%
of an integrated steel mill's total energy use. Metallurgical coal
burns sporadically and reduces into a sticky mass. Processed coke,
however, burns steadily inside and out and is not crushed by the
weight of the iron ore in the blast furnace. Inside the narrow
confines of the coke oven, coal is heated without oxygen for 18
hours to drive off gases and impurities.
Coke Oven Battery A
set of ovens that process coal into coke. Coke ovens are constructed
in batteries of ten - 100 ovens that are 20 feet tall, 40 feet long
and less than two feet wide. Coke batteries, because of the exhaust
fumes emitted when coke is pushed from the ovens, often are the
dirtiest area of a steel mill complex.
Cold Reduction
Special mills roll cold coils of pickled hot-rolled sheet to make
the steel thinner, smoother and stronger than can be created on a
hot mill. Stands of rolls in a cold-reduction mill are set very
close together and press a sheet of steel from one-quarter inch
thick into less than an eighth of an inch, while more than doubling
its length.
Cold-Rolled Strip
(Sheet) Sheet steel that has been pickled and run through a
cold-reduction mill. Strip has a final product width of
approximately 12 inches, while sheet may be more than 80 inches
wide. Cold-rolled steel is considerably thinner and stronger than
hot-rolled sheet, so it will sell for a premium (see Sheet
Steel).
Cold Working
(Rolling) Changes in the structure
and shape of steel achieved through rolling, hammering, or
stretching the steel at a low temperature (often room temperature).
To create a permanent increase in the hardness and strength of the
steel. The application of forces to the steel causes changes in the
composition that enhance certain properties. In order for these
improvements to be sustained, the temperature must be below a
certain range because the structural changes are eliminated by
higher temperatures.
Consumption Measures
the physical use of steel by end users. Steel consumption estimates,
unlike steel demand figures, account for changes in
inventories.
- Apparent
Supply. Derived demand for steel
using AISI reported steel mill shipments plus Census Bureau
reported imports, less Census Bureau reported exports. Domestic
market share percentages are based on this figure, which does
not take into account any changes in
inventory.
Continuous Casting A
method of casting steel into a billet. bloom or slab directly from
its molten form. Continuous casting avoids the need for large,
expensive mills for rolling ingots into slabs. Continuous cast slabs
also solidify in a few minutes versus several hours for an ingot. As
a result, the chemical composition and mechanical properties are
more uniform. Steel from the BOF or electric furnace is poured into
a tundish (a shallow vessel that looks like a bathtub) atop the
continuous caster. As steel carefully flows from the tundish down
into the water-cooled copper mold of the caster, it solidifies into
a ribbon of red-hot steel. At the bottom of the caster, torches cut
the continuously flowing steel to form slabs or blooms.
Contract Sales Steel
products committed to customers through price agreements extending
three to 12 months. About one-half of all flat-rolled steel is sold
on this basis, primarily because the auto companies sign agreements
to cover at least one year's production. Price increases that the
steel mills might announce during the year do not generally affect
the revenues from the contract side of the business.
Conversion Cost
Resources spent to process material in a single stage, from one type
to another. The costs of converting iron ore to hot metal or
pickling hot-rolled coil can be isolated for analysis.
Converter/Processor
Demand from steel customers like rerollers and tube makers, which
process steel into a more finished state, such as pipe, tubing and
cold-rolled strip before selling it to end users. Such steel
generally is not sold on contract, making the converter segment of
the mills' revenues more price sensitive than their supply contracts
to the auto manufacturers.
COREX® COREX
is a coal-based smelting process that yields hot metal or pig iron.
The output can be used by integrated mills or EAF mills. The process
gasifies non-coking coal in a smelting reactor, which also produces
liquid iron. The gasified coal is fed into a shaft furnace where it
removes oxygen from iron ore lumps, pellets or sinter; the reduced
iron is then fed to the smelting reactor.
Corrosion The
gradual degradation or alteration of steel caused by atmosphere,,
moisture, or other agents.
Culvert Pipe Heavy
gauge, galvanized steel that is spiral-formed or riveted into
corrugated pipe, which is used for highway drainage
applications.
Cut-to-Length
Process to uncoil sections of flat-rolled steel and cut them into a
desired length. Product that is cut-to-length is normally shipped
flat-stacked. Go back to the top

Defined Benefit
Retirement Plan A type of pension plan whereby the employer
promises to make pension payments to retired employees in specified
amounts, regardless of the performance of the fund established to
provide for the retirees or the amount contributed. Because the
employees' total years of service and their length of retirement are
uncertain, the employer's future liabilities must be estimated and
can fluctuate over time.
Defined Contribution
Retirement Plan A pension plan in which the employer promises to
make specified contributions to the pension fund, but the amount of
pension benefits ultimately paid to retired employees depends on how
well the pension fund's assets are managed. There are no balance
sheet items for Defined Contribution Plans because all liabilities
are satisfied in full each year.
Desulfurization
Operation that injects a chemical mixture into a ladle full of hot
metal to remove sulfur prior to its charging into the Basic Oxygen
Furnace. Sulfur enters the steel from the coke in the blast furnace
smelting operation, and there is little the steelmaker can do to
reduce its presence. Because excess sulfur in the steel impedes its
welding and forming characteristics, the mill must add this step to
the steel-making process.
Direct Reduced Iron
(DRI) Processed iron ore that is iron-rich enough to be used as
a scrap substitute in electric furnace steelmaking. As mini-mills
expand their product abilities to sheet steel, they require much
higher grades of scrap to approach integrated mill quality. Enabling
the mini-mills to use iron ore without the blast furnace, DRI can
serve as a low residual raw material and alleviate the mini-mills'
dependence on cleaner, higher-priced scrap. The impurities in the
crushed iron ore are driven off through the use of massive amounts
of natural gas. While the result is 97% pure iron (compared with
blast furnace hot metal, which, because it is saturated with carbon,
is only 93% iron), DRI is only economically feasible in regions
where natural gas is attractively priced.
Drawn-Over-Mandrel A
procedure for producing specialty tubing using a drawbench to pull
tubing through a die and over a mandrel, giving excellent control
over the inside diameter and wall thickness. Advantages of this
technique are its inside and outside surface quality and gauge
tolerance. Major markets include automotive applications and
hydraulic cylinders.
Drill Pipe Pipe used
in the drilling of an oil or gas well. Drill pipe is the conduit
between the wellhead motor and the drill bit. Drilling mud is pumped
down the center of the pipe during drilling to lubricate the drill
bit and transmit the drilled core to the surface. Because of the
high stress, torque and temperature associated with well drilling,
drill pipe is a seamless product.
Ductility Ability of
steel to undergo permanent changes in shape without fracture at room
temperature.
Dumping Dumping
occurs when imported merchandise is sold in, or for export to, the
domestic market at less than the normal value of the merchandise,
i.e., a price which is less than the price at which identical or
similar merchandise is sold in the comparison market, the home
market (market of exporting country) or third-country market (market
used as proxy for home market in cases where home market cannot be
used).
Dumping Margin The
amount by which the normal value exceeds the export price or
constructed export price of the subject merchandise.
Duplex A category of
stainless steel with high amounts of chromium and moderate nickel
content. The duplex class is so named because it is a mixture of
austenitic (chromium-nickel stainless class) and ferritic (plain
chromium stainless category) structures. This combination was
originated to offer more strength than either of those stainless
steels. Duplex stainless steels provide high resistance to stress
corrosion cracking (formation of cracks caused by a combination of
corrosion and stress) and are suitable for heat exchangers,
desalination plants, and marine applications.
Go back to the top

Edge Rolling (Edge
Conditioning)
Rolling a strip of steel to
smooth the edges. By removing the burr off the coil, it is safer for
customers to manipulate.
Electric Arc Furnace
(EAF)
Steel-making furnace where
scrap is generally 100% of the charge. Heat is supplied from
electricity that arcs from the graphite electrodes to the metal
bath. Furnaces may be either an alternating current (AC) or direct
current (DC). DC units consume less energy and fewer electrodes, but
they are more expensive.
Electric Resistance
Welded (ERW) Pipe
Pipe made from strips of
hot-rolled steel which are passed through forming rolls and welded.
While seamless pipe is traditionally stronger and more expensive
than comparable ERW pipe, ERW technology is improving and the
technique now accounts for approximately 48% of OCTG shipments by
tonnage.
Electrical Steel
(See Silicon Electrical Steel) Go back to the top

Fabricator
A producer of
intermediate products that does not also produce primary metal. For
example, a rebar (see Reinforcing Bar) fabricator purchases
rebar and processes the material to the specifications of a
particular construction project.
FAS 106
An accounting rule
established in 1990 that requires companies to change their
accounting for the cost of their retirees' future nonpension
benefits (life insurance and health services). What was once "pay as
you go" or a "cash basis" expense item has been changed to an
accrual basis. Such costs are now recognized during the employees'
working years. When the steel companies shifted to the new
accounting rule, most companies charged the "catch-up" to equity in
large one-time write-downs as they established the new liabilities
on their balance sheets.
FAS 109
An accounting rule
for deferred taxes that requires companies to explain within their
financial statements the difference between the tax expense found on
the income statement and the check actually sent to the Internal
Revenue Service (IRS). (This rule superseded FAS 96 and APB
II.) Some steel companies carry net operating losses (NOLS) on
their balance sheets as assets that can be used to offset future
taxes. Under the rules of FAS 109, however, a valuation allowance
may be recorded to reduce these NOLs unless there is a high
probability that they will be used.
Fastmet
A process to
directly reduce iron ore to metallic iron pellets that can be fed
into an electric arc furnace with an equal amount of scrap. This
process is designed to bypass the coke oven-blast furnace route to
produce hot metal from iron ore. It is also one of several methods
that mini-mills might use to reduce their dependence on high-quality
scrap inputs (see Direct Reduced Iron and Hot Briquetted
Iron).
Feedstock
Any raw
material.
Ferritic
The second-largest
class of stainless steel, which constitutes approximately 25% of
stainless production.
Ferritic stainless steels
are plain chromium
steels with no significant nickel content; the lack of nickel
results in lower corrosion resistance than the austenitics
(chromium-nickel stainless steels). Ferritics are best suited for
general and high-temperature corrosion applications rather than
services requiring high strength. They are used in automotive trim
and exhaust systems, interior architectural trim, and hot water
tanks. Two of the most common grades are type 430 (general-purpose
grade for many applications, including decorative ones) and type 409
(low-cost grade well suited to withstanding high
temperatures).
Ferrochrome
An alloy of iron
and chromium with up to 72% chromium. Ferrochrome is commonly used
as a raw material in the making of stainless steel.
Ferrous Alloy
(See Alloy
Steel.)
Finmet
The process reduces
iron ore fines with gas in a descending series of fluidized bed
reactors. The reduced iron is hot briquetted.
Finish
The surface
appearance of steel after final treatment.
Finishing Facilities
The portion of the
steel-making complex that processes semi-finished steel (slabs or
billets) into forms that can be used by others. It is the opposite
of the Hot End. Finishing operations can include rolling
mills, pickle lines, tandem mills, annealing facilities, and temper
mills.
Flat-Rolled
Steel
Category of steel that includes Sheet, Strip and Tin Plate
among others.
Flux
An iron cleaning
agent. Limestone and lime react with impurities within the metallic
pool to form a slag that floats to the top of the relatively heavier
(and now more pure) liquid iron.
FOB Pricing
Freight on Board
Pricing. Phrase that explains whether the transportation costs of
the steel are included. "FOB Mill" is the price of steel at the
mill. not including shipping.
Freight Equalization.
A common
industry practice when a mill sells steel outside its geographic
area; it will assume any extra shipping costs (relative to the
competition) to quote the customer an equivalent price to get the
business. Go back to the top

Galvanized Steel
Steel coated
with a thin layer of zinc to provide corrosion resistance in
underbody auto parts, garbage cans, storage tanks, or fencing wire.
Sheet steel normally must be cold-rolled prior to the galvanizing
stage.
Steel is run through a molten zinc coating bath,
followed by an air stream "wipe" that controls the thickness of
the zinc finish.
Electrogalvanized. Zinc plating process whereby the molecules on the
positively charged zinc anode attach to the negatively charged
sheet steel. The thickness of the zinc coating is readily
controlled. By increasing the electric charge or slowing the speed
of the steel through the plating area, the coating will
thicken.
Differences.
Electrogalvanizing equipment is more expensive to
build and to operate than hot dipped, but it gives the steelmaker
more precise control over the weight of the zinc coating. The
automotive manufacturers, because they need the superior welding,
forming and painting ability of electrogalvanized steel, purchase
90% of all tonnage produced.
Galvalume™
Steel
sheet with a unique coating of 55% aluminum and 45% zinc that
resists corrosion. The coating is applied in a continuous hot-dipped
process, which improves the steel's weather resistance.
Galvalume™ is a trademark of BHP Steel, and the product is
popular in the metal building market.
Gauge
The thickness of
sheet steel. Better-quality steel has a consistent gauge to prevent
weak spots or deformation.
Greenfield Site
Mill that is built
"from scratch," presumably on a green field.
Go back to the top

Hardening
Process
that increases the hardness of steel, i.e., the degree to which
steel will resist cutting, abrasion, penetration, bending, and
stretching, The increased endurance provided by hardening makes
steel suitable for additional applications. Hardening can be
achieved through various methods, which include: (1) heat treatment,
where the properties of steel are altered by subjecting the steel to
a series of temperature changes; and (2) cold working, in which
changes in the structure and shape of steel are achieved through
rolling, hammering, or stretching the steel at a relatively low
temperature.
Heat
A batch of refined
steel. A basic oxygen or electric furnace full of steel. One heat of
steel will be used to cast several slabs, blooms or
billets.
Heat Treatment
Altering the
properties of steel by subjecting it to a series of temperature
changes. To increase the hardness, strength, or ductility of steel
so that it is suitable for additional applications. The steel is
heated and then cooled as necessary to provide changes in the
structural form which will impart the desired characteristics. The
time spent at each temperature and the rates of cooling have
significant impact on the effect of the treatment.
Heavy Structural
Shapes A
general term given to rolled flanged sections that have at least one
dimension of their cross sections three inches or greater. The
category includes beams, channels, tees and zees if the depth
dimension is three inches or greater and angles if the length of the
leg is three inches or greater.
High-Carbon Steel
Steel with more
than 0.3% carbon. The more carbon that is dissolved in the iron, the
less formable and the tougher the steel becomes. High-carbon steel's
hardness makes it suitable for plow blades, shovels, bedsprings,
cutting edges, or other high-wear applications.
Hot Band (Hot-Rolled
Steel) A coil
of steel rolled on a hot-strip mill (hot-rolled steel). It can be
sold in this form to customers or further processed into other
finished products,
Hot-Briquetted Iron
(HBI)
Direct-reduced iron that has been processed into briquettes.
Instead of using a blast furnace, the oxygen is removed from the ore
using natural gas and results in a substance that is 90%-92% iron.
Because DRI may spontaneously combust during transportation, HBI is
preferred when the metallic material must be stored or
moved.
Hot End
The section of a
steel-making complex from the furnace up to, but not including, the
hot-strip mill.
Hot Metal
The name for the
molten iron produced in a blast furnace. It proceeds to the basic
oxygen furnace in molten form or is cast as pig iron.
Hot-Strip Mill
A rolling mill of
several stands of rolls that converts slabs into hot-rolled coils.
The hot-strip mill squeezes slabs, which can range in thickness from
two to ten inches, depending on the type of continuous caster,
between horizontal rolls with a progressively smaller space between
them (while vertical rolls govern the width) to produce a coil of
flat-rolled steel about a quarter-inch in thickness and a quarter
mile in length.
HYL I, HYL III
Processes for
producing DRI and HBI developed by Hylsa. The processes reduce iron
ore lump or pellets with reformed natural gas in a vertical shaft
furnace. The HYL I process uses four fixed-bed reactors; HYL III
uses a single shaft furnace.
Hydroforming
A forming process
in which a tube is placed into a forming die. The tube is then
formed to the shape of the die through the application of internal
water pressure. The hydroforming process allows for severe shape
deformation, making it ideal for automotive structural parts such as
engine cradles, radiator supports and body rails. Various shaped and
sized holes can be punched in the tube almost anywhere during the
process. Go back to the top

I-Beams
Structural
sections on which the flanges are tapered and are typically not as
long as the flanges on wide-flange beams. The flanges are thicker at
the cross sections and thinner at the toes of the flanges. They are
produced with depths of three to 24 inches.
Ingot
A form of
semi-finished steel. Liquid steel is teemed (poured) into molds,
where it slowly solidifies. Once the steel is solid, the mold is
stripped, and the 25- to 30-ton ingots are then ready for subsequent
rolling or forging.
lnmetco
Inmetco
is a coal-based process similar to FASTMET that uses iron oxide
fines and pulverized coal to produce a scrap substitute. Mill scale
and flue dust, inexpensive byproducts of steel making, can be mixed
with the iron oxide fines. Inmetco, unlike other direct reduction
products, is intended to be hot charged into an EAF, with attendant
energy savings. The process includes three steps. First, iron oxide
fines, pulverized coal and a binder are formed into pellets. Second,
the pellets, two-three layers deep, are heated in a gas-fired rotary
hearth furnace for 15-20 minutes to produce sponge iron.
Subsequently, the iron must be de-sulfurized. The coal in the
pellets provides much of the energy required in the second
phase.
Integrated Mills
These facilities
make steel by processing iron ore and other raw materials in blast
furnaces. Technically, only the hot end differentiates integrated
mills from mini-mills. However, the differing technological
approaches to molten steel imply different scale efficiencies and,
therefore, separate management styles, labor relations and product
markets. Nearly all domestic integrated mills specialize in
flat-rolled steel.
Interstitial Free
Steel A
recently developed sheet steel product with very low carbon levels
that is used primarily in automotive deep-drawing applications.
Interstitial Free Steel's improved ductility (drawing ability) is
made possible by vacuum degassing.
Iron Carbide
One of several
substitutes for high-quality, low-residual scrap for use in electric
furnace steelmaking. Iron carbide producers use natural gas to
reduce iron ore to iron carbide.
Iron Ore
Mineral containing
enough iron to be a commercially viable source of the element for
use in steelmaking. Except for fragments of meteorites found on
Earth, iron is not a free element; instead, it is trapped in the
earth's crust in its oxidized form. Go back to the top
  
Ladle Metallurgy Furnace
(LMF)
An intermediate steel processing unit that further refines
the chemistry and temperature of molten steel while it is still in
the ladle. The ladle metallurgy step comes after the steel is melted
and refined in the electric arc or basic oxygen furnace, but before
the steel is sent to the continuous caster.
Legacy Costs
Any costs that are
associated with prior operations. Employee liabilities (pensions and
health care benefits) and environmental cleanup costs usually are
included under this moniker.
Leveling Line
A process to
flatten any shape deficiencies (wavy edges and buckles) in the
sheet, prior to final shipment. Most cold-rolled sheet initially has
a crowned cross section that, if such a shape is undesirable to the
customer, must be flattened in the leveling line.
Life Cycle Costing
An accounting
method of costing where expenses are allocated over the life of the
product. Life cycle costs are often lower for stainless steel than
for alternatives despite a higher initial outlay because stainless
products generally last longer and require little
maintenance.
Light-Gauge Steel
Very thin steel
sheet that has been temper-rolled or passed through a cold-reduction
mill. Light gauge steel normally is plated with tin or chrome for
use in food containers.
Line Pipe
Pipe used in the
surface transmission of oil, natural gas and other
fluids.
Long Products
Classification of steel products that includes bar products, rod
and structural products. Long products are the traditional products
produced by mini-mills.
Low-Carbon Steel
Steel with less
than 0.005% carbon is more ductile (malleable): It is capable of
being drawn out or rolled thin for use in automotive body
applications. Carbon is removed from the steel bath through vacuum
degassing. Go back to the top

M sections (Bantam
Beams™, Junior Beams™ )
Light footweight beams primarily used in the
construction of pre-engineered housing. These beams are produced in
lighter footweights, usually six to ten pounds per foot, than
traditional structural products.
Man-Hours Per Ton
This is a measure
of labor efficiency - the ratio of total hours worked by steel
employees to the tons shipped for a given period. Changes in the
inventory level and work that is contracted out will affect the
reported measurement. Figures normally are announced annually to
smooth any inventory distortions.
Martensitic
Small category of
stainless steel characterized by the use of heat treatment for
hardening and strengthening. Martensitic stainless steels are plain
chromium steels with no significant nickel content. They are
utilized in equipment for the chemical and oil industries and in
surgical instruments. The most popular martensitic stainless steel
is type 410 (a grade appropriate for non-severe corrosion
environments requiring high strength).
Merchant Bar
A group of
commodity steel shapes that consist of rounds, squares, flats,
strips, angles, and channels that fabricators, steel service centers
and manufacturers cut, bend and shape into products. Merchant
products require more specialized processing than reinforcing
bar.
MIDREX Direct Reduction
Process MIDREX
was developed by the Midrex Corporation, which produces about 65% of
DRI globally. The continuous process uses iron ore lumps or pellets
as a raw material; the limit is roughly 70% pellet. Reformed natural
gas flows into the bottom of a vertical shaft furnace as ore is
charged into the top. As gas rises through the ore, which is falling
through the shaft, it removes oxygen from the ore. The DRI is
removed from the bottom of the furnace. It can be discharged as
pellets and lumps, or hot briquetted.
Mini-Mills
Normally defined as
a steel mill that melts scrap metal to produce commodity products.
Although the mini-mills are subject to the same steel processing
requirements after the caster as the integrated steel companies,
they differ greatly in regard to their minimum efficient size, labor
relations, product markets, and management style.
Molybdenum (Mo)
An alloying element
used as a raw material for some classes of stainless steel.
Molybdenum in the presence of chromium enhances the corrosion
resistance of stainless steel. Go back to the top

Net Operating Loss
(NOLS)
An income-averaging provision that allows companies with
losses to either carry forward the loss up to 15 years to offset
otherwise taxable future income or carry back the NOLs up to three
years to receive a refund for taxes previously paid (see FAS
109).
Nickel (Ni)
An alloying element
used as a raw material for certain classes of stainless steel.
Nickel provides high degrees of ductility (ability to change shape
without fracture) as well as resistance to corrosion. Approximately
65% of all nickel is used in the making of stainless
steel.
No. 1 Heavy Melt
Obsolete steel scrap grade, at least one-quarter inch
in thickness and in sections no larger than five feet by two feet.
Much of the metal comes from demolished buildings, truck frames and
heavy duty springs. Mini-mills are primary consumers of No. I heavy
scrap. Go back to the top

Oil Country Tubular
Goods (OCTG) Label applied to the pipe products used
by petroleum exploration customers. OCTG includes casing, drill pipe
and oil well tubing which, depending on their use, may be formed
through welded or seamless processes.
OPEB Expense
Other
Postretirement Employment Benefits. Usually refers to health care
obligations to a mill's retired workers, although its meaning also
can include layoff benefits (see FAS 106).
Open Hearth Furnace
A broad, shallow
hearth to refine pig iron and scrap into steel. Heat is supplied
from a large, luminous flame over the surface, and the refining
takes seven to nine hours. Open Hearths, at one time the most
abundant steelmaking furnace among integrated companies, have been
replaced by the basic oxygen furnace.
Operating Rates
The ratio of raw
steel production to the mill's stated capacity. Each December, steel
companies report to the AISI its estimated capacity (if they could
sell all steel they produced) for the following year, adjusted for
any facility downtime.
Order Rate
The ratio of new
orders recorded to the mill's capacity to produce the steel to fill
the orders. Many analysts view trends in the order rate as
harbingers of future production levels.
Oscillating A method of winding narrow strip steel over a much wider
roll. Customers want to have as much steel on a coil as will fit in
their machines, so they can spend less time moving the material and
more time using it. By coiling the strip like fishing line (or
thread) over a spool, a much longer strip can fit onto a coil of
proper diameter. Oscillate-wound coils allow the customer to enjoy
longer processing runs. Go back to the top

PM 2.5
The moniker
for the Environmental Protection Agency's new Particulate Matter
standards. The EPA is revising current PM standards and establishing
a new PM 2.5 standard regarding the release of particulate matter
down to 2.5 micrometers in diameter (less than
1/3 the width of a human hair).
Peak Earnings
The ultimate
earnings level of a company at the top of the business cycle. This
is the expected profit during the time of the highest commodity
demand and the strongest product pricing.
Pellets (See
Agglomerating Processes)
Pickling
Process that cleans
a steel coil of its rust, dirt and oil so that further work can be
done to the metal. When hot-rolled coils cool, rust forms on the
unprotected metal; often coils are stored or transported while
exposed to outside air and water. Through a conti nuous process, the
steel is uncoiled and sent through a series of hydrochloric acid
baths that remove the oxides (rust). The steel sheet is then rinsed
and dried.
Pig Iron
The name for the
cast iron produced in a blast furnace that contains a large quantity
of carbon (above 1.5%). Mini-mills also may charge pig iron in their
furnaces in the place of scrap. Named long ago when molten iron was
poured through a trench in the ground to flow into shallow earthen
holes, the arrangement looked like newborn pigs suckling. The
central channel became known as the "sow," and the molds were
"pigs."
Piling (Sheet
Piling) A
structural steel product with edges designed to interlock; used in
the construction of cofferdams or riverbank
reinforcement.
Pipe
Technically a tube
used to transport fluids or gases. However, pipe and tube are often
used interchangeably in steel lexicon, with a given label applied
primarily as a matter of historical use.
Plate
Sheet steel with a
width of more than eight inches, with a thickness ranging from one
quarter of an inch to more than one foot (see
Sheet.).
Powder Metals Fabrication technology in which fine metallic
powder is compacted under high pressure and then heated at a
temperature slightly below the melting point to solidify the
material. Primary users of powder metal parts are auto, electronics
and aerospace industries.
Precipitation Hardening
(PH) A small
group of stainless steels with high chromium and nickel content,with
the most common types having characteristics close to those of
martensitic (plain chromium stainless class with exceptional
strength) steels. Heat treatment provides this class with its very
high strength and hardness. Applications for PH stainless steels
include shafts for pumps and valves as well as aircraft
parts.
Pulverized Coal
Injection System (PCI)
A blast furnace enhancement to reduce an integrated mill's
reliance on coke (because of environmental problems with its
production). Up to 30% of the coke charged into the blast furnace
can be replaced by this talcum-like coal powder, which is injected
through nozzles at the bottom of the furnace.
Go back to the top

Q-BOP
Modified
Basic Oxygen Furnace in which the oxygen and other gases are blown
in from the bottom, rather than from the top. While the Q-BOP stirs
the metal bath more vigorously, allowing for faster processing, the
design produces essentially the same steel grades as the top-blowing
basic oxygen furnace. Today's state-of-the-art furnace design
combines the previous technologies: 60% of the oxygen is blown from
above with the rest blown through the bottom of the
vessel.
Qualification Trials
The testing
required for a new process adopted to make certain grades of steel
with exacting end uses. In order for the process to become
qualified, the steel made by the process must be
tested. Go back to the top

Reducing Agent
Either
natural gas or coal can be used to remove the oxygen from iron ore
in order to produce a scrap substitute. In gas-based processes, the
iron ore is heated in a vessel as reformed natural gas passes
through. In coal-based processes, iron ore is combined with gasified
or ground coal and heated. The oxygen in the ore combines with
carbon and hydrogen in the gas or coal, producing reduced, or
metallic, iron.
Refractory Brick
Heat-resistant
brick. Because its melting point is well above the operating
temperatures of the process, refractory bricks line most steelmaking
vessels that come in contact with molten metal, like the walls of
the blast furnace, sides of the ladles and inside of the
BOF.
Reinforcing Bar (Rebar)
A
commodity-grade steel used to strengthen concrete in highway and
building construction.
Reline
The process of
replacing the refractory lining of a liquid steel vessel. Once it
wears out, the brick lining of a furnace must be cooled, stripped
and replaced. This maintenance can be significant because a blast
furnace reline may require up to three months to
complete.
Residuals
The impurities in
mini-mill steel as the result of the mix of metals entering the
process dissolved in obsolete scrap. Residuals are key concerns
regarding the mini-mills' recent entry into the flat-rolled market,
where high residuals can leave sheet steel too brittle for customer
use.
Reversing Mill
The stand of rolls
used to reduce steel sheet or plate by passing the steel back and
forth between the rolls; the gap between the rolls is reduced after
each pass.
Rod
Round, thin semi-finished steel
length that is rolled from a billet and coiled for further
processing. Rod is commonly drawn into wire products or used to make
bolts and nails. Rod trains (rolling facilities) can run as fast as
20,000 feet per minute - more than 200 miles per hour.
Roll Force Systems
Mill stands place
considerable pressure on slabs, blooms and coils to further process
the material. There are two general ways of applying the force to
the steel - screw and hydraulic systems.
his older method used the
basic principle of the screw to adjust the space between the mill
rolls. Because metal touches metal, these configurations will
eventually wear down and can cause quality
problems.
Hydraulic
(Pancake Cylinder).
This modern system uses fluid pressure
to rapidly adjust the roll spacing several times per second. These
minute, instantaneous adjustments allow for superior gauge
tracking and higher-quality products.
Go back to the top

Scale
The oxide
of iron that forms on the surface of steel after
heating.
Scrap
Ferrous
(iron-containing) material that generally is re-melted and recast
into new steel. Integrated steel mills use scrap for up to 25% of
their basic oxygen furnace charge; 100% of the mini-mills' raw
material for their electric furnaces generally is
scrap.
Waste steel that is generated from within the steel mill,
through edge trimming and rejects. It normally is sent directly
back to the furnace.
Prompt (Industrial)
Scrap. Excess
steel that is trimmed by the auto and appliance stampers and
auctioned to scrap buyers as factory bundles. This is a
high-quality scrap as the result of its low-residual content and
consistent chemistry.
Obsolete Scrap. Iron-bearing trash. Automobile hulks,
worn-out refrigerators and useless storage tanks, for example, can
be recovered from the junkyard and remelted. The residual impurity
of such scrap normally relegates obsolete scrap to the mini-mills
(see No. I Heavy Melt).
Scrap Substitute
Feedstock that can
be charged in place of scrap in electric arc furnaces and basic
oxygen furnaces. Scrap substitutes include, among others, DRI, HBI,
iron carbide, and pig iron.
Seamless Pipe
Pipe made from a
solid billet which is heated then rotated under extreme pressure.
This rotational pressure creates an opening in the center of the
billet which is then shaped by a mandrel to form pipe.
Secondary Steel
Steel that does not
meet the original customer's specifications because of a defect in
its chemistry, gauge or surface quality. Mills must search to find
another customer (that can accept the lower quality) to take the
off-spec steel at a discount. While secondary will not affect the
reported yield, margins will suffer.
Sendzimir Mill
(Z-mill)
Compact mill used for rolling cold coils of stainless steel
in order to make the steel thinner, smoother, and stronger. Used to
control the thickness of steel better at less capital cost and to
roll thinner sheets and strips. Stainless steel sheet or strip
passes between a matching pair of small work rolls with extremely
smooth surfaces, heavily reinforced by clusters of back-up rolls.
The rolls reduce the steel to the desired thickness.
Service Center
A catchall name for
an operation that buys steel, often processes it in some way and
then sells it in a slightly different form. A service center is
distinguished form an end-user by the fact that, unlike an end-user,
a service center sells steel, not a fabricated product. Service
centers are manufacturers to the extent that they add labor to steel
by providing a service.
Shape Correcting
Rolling, heating
and quenching steel sheets often affect the dimensions of the steel.
Levelers, temper mills and edge trimmers rework the processed steel
to match customer specifications.
Shearing
If the edges of
sheet and strip are not controlled during reduction, they must be
trimmed parallel by shears. This process may be performed by either
the steel mill or steel processor to match customer
needs.
Sheet Steel
Thin, flat-rolled
steel. Coiled sheet steel accounts for nearly one-half of all steel
shipped domestically and is created in a hot-strip mill by rolling a
cast slab flat while maintaining the side dimensions. The malleable
steel lengthens to several hundred feet as it is squeezed by the
rolling mill. The most common differences among steel bars, strip,
plate, and sheet are merely their physical dimensions of width and
gauge (thickness).
Product Classification
by Size
Specified Thickness
Specified Width in Inches
In Inches Up to 6 Over Over
Over Over 48
6 to 8 8 to 12 12 to 48
0.2300 + Bar Bar Plate
Plate Plate
0.2299 - 0.2040 Bar Strip
Strip Sheet Plate
0.2039 - 0.1800 Strip Strip
Strip Sheet Plate
Shredded Scrap
Fist-sized,
homogenous pieces of old automobile hulks. After cars are sent
through a shredder, the recyclable steel is separated by magnets.
Mini-mills consume shredded scrap in their electric arc furnace
operations.
Silicon Electrical
Steel A type of
specialty steel created by introducing silicon at the BOF during the
steelmaking process. Electrical steel exhibits certain magnetic
properties, which make it optimum for use in transformers, power
generators and electric motors.
The metal's grain runs parallel within the steel,
permitting easy magnetization along the length of the steel.
Although grain-oriented steel may be twice as expensive to
produce, its magnetic directional characteristics enable power
transformers, made from this metal, to absorb less energy during
operation.
Non-Grain-Oriented.
Because there
is no preferential direction for magnetization, non-grain-oriented
steel is best used in rotating apparatus such as electric
motors.
Sintering
A process that
combines iron-bearing particles, once recovered from environmental
control filters, into small pellets. Previously, these materials
were too fine to withstand the air currents of the smelting process
and were thrown away. The iron is conserved now because the chunks
can be charged into the blast furnace (see Agglomerating
Processes).
Skelp
Steel that is the
entry material to a pipe mill. Resembles hot-rolled strip, but its
properties allow for the severe forming and welding operations
required for pipe production.
Slab
The most common
type of semi-finished steel. Traditional slabs measure ten inches
thick and 30-85 inches wide (and average about 20 feet long), while
the output of the recently developed "thin slab" casters is
approximately two inches thick. Subsequent to casting, slabs are
sent to the hot-strip mill to be rolled into coiled
sheet.
Slag
The impurities in a
molten pool of iron. Flux such as limestone may be added to foster
the congregation of undesired elements into a slag. Because slag is
lighter than iron, it will float on top of the pool, where it can be
skimmed.
Slitting
Cutting a sheet of
steel into narrower strips to match customer needs. Because steel
mills have limited flexibility as to the widths of the sheet that
they produce, service centers normally will cut the sheet for the
customer.
Special Bar Quality
(SBQ) SBQ
represents a wide variety of higher quality carbon and alloy bars
that are used in the forging, machining and cold-drawing industries
for the production of automotive parts, hand tools, electric motor
shafts and valves. SBQ generally contains more alloys than merchant
quality and commodity grades of steel bars and are produced with
more precise dimensions and chemistry.
Specialty Steel
Category of steel
that includes electrical (see Silicon Electrical Steel), alloy
(see Alloy Steel) stainless (see Stainless Steel)
and tool (see Tool Steels) steels.
Specialty Tube
Refers to a wide
variety of high-quality custom-made tubular products requiring
critical tolerances, precise dimensional control and special
metallurgical properties. Specialty tubing is used in the
manufacture of automotive, construction and agricultural equipment
and in industrial applications such as hydraulic cylinders, machine
parts and printing rollers. Because of the rage of industrial
applications, the market typically follows general economic
conditions.
Spot Market
Sales for delivery
in less than three months.
Stainless Steel
The term for grades
of steel that contain more than 10% chromium, with or without other
alloying elements. Stainless steel resists corrosion, maintains its
strength at high temperatures, and is easily maintained. For these
reasons, it is used widely in items such as automotive and food
processing products, as well as medical and health equipment. The
most common grades of stainless steel are:
The most
commonly specified austenitic (chromium-nickel stainless class)
stainless steel, which accounts for more than half of the
stainless steel produced in the world. This grade withstands
ordinary corrosion in architecture, is durable in typical food
processing environments, and resists most chemicals. Type 304 is
available in virtually all product forms and finishes.
Type
316. Austenitic
(chromium-nickel stainless class) stainless steel containing 2%-3%
molybdenum (whereas 304 has none). The inclusion of molybdenum
gives 316 greater resistance to various forms of
deterioration.
Type 409.
Ferritic
(plain chromium stainless category) stainless steel suitable for
high temperatures. This grade has the lowest chromium content of
all stainless steels and thus is the least expensive.
Type 410.
The most widely used martensitic (plain chromium
stainless class with exceptional strength) stainless steel,
featuring the high level of strength conferred by the
martensitics. It is a low cost, heat-treatable grade suitable for
non-severe corrosion applications.
Type 430.
The most widely used ferritic (plain chromium
stainless category) stainless steel, offering general-purpose
corrosion resistance, often in decorative
applications.
Statistical Process
Control (SPC) A
technique used to predict when a steelmaking function's quality may
deteriorate. By tightly monitoring the product's variance from
specifications, the operator can determine when to apply
preventative maintenance to a machine before any low-quality
(secondary) steel is produced.
Steckel Mill
A reversing steel
sheet reduction mill with heated coil boxes at each end. Steel sheet
or plate is sent through the rolls of the reversing mill and coiled
at the end of the mill, reheated in the coil box, and sent back
through the Steckel stands and recoiled. By reheating the steel
prior to each pass, the rolls can squeeze the steel thinner per pass
and impart a better surface finish.
Steel Intensity
The amount of steel
used per unit of gross domestic product. Intensity reflects the
secular demand for steel, as opposed to cyclical demand. The amount
of steel used in vehicles and the popularity of alternative
materials affect the intensity, or how much steel is needed per unit
produced. The state of the economy, however, determines how many
units.
Steel-intensive
Products
Consumer products such as automobiles and appliances that,
because so much of their weight is from steel, exhibit a high demand
correlation with steel. Because the average car weighing 2,900
pounds is 53% steel, rising auto sales directly increase steel
demand,
Steel Service Center
Inventories (SSCI).
End-of-period material stocks reported by the Steel Service
Center Institute
Ratio of the end-of-period inventory to average
monthly level of sales for the period.
Steel Strapping
Banding and
packaging material that is used to close and reinforce shipping
units, such as bales, boxes, cartons, coils, crates, and
skids.
Strength
Properties related
to the ability of steel to oppose applied forces. Forms of strength
include withstanding imposed loads without a permanent change in
shape or structure and resistance to stretching.
Stress Corrosion
Cracking (SCC)
Slow growth of cracks in stainless steel caused by the
combined effect of mechanical stress and exposure to a corrosive
environment.
Strip
Thin, flat steel
that resembles hot-rolled sheet, but it is normally narrower (up to
12 inches wide) and produced to more closely controlled thicknesses.
Strip also may be cut from steel sheet by a slitting machine (see
Sheet Steel).
Structurals
Steel product group
that includes 1-beams, H-beams, wide-flange beams and sheet piling.
These products are used in the construction of multi-story
buildings, industrial buildings, bridge trusses, vertical highway
supports, and riverbank reinforcement.
Substrate
Raw material used
as an input for steel processing: For example, hot-rolled steel is
the substrate for cold-rolling operations.
Go back to the top

Taconite
Natural
mineral containing less than 30% iron. It is the primary ore used in
blast furnaces. Domestic supplies of iron-rich ores (greater than
50% iron) were largely depleted in the 1940s, so integrated steel
companies now process the lower-grade taconite to make it
useful.
Tailored Blanks
A section of sheet
or strip that is cut-to-length and trimmed to match specifications
for the manufacturer's stamping design for a particular part.
Because excess steel is cut away (to save shipping costs), all that
remains for the stamper is to impart the three-dimensional shape
with a die press (see Blanking).
Tandem Mill
A type of
cold-rolling mill, the tandem mill imparts greater strength, a
uniform and smoother surface and reduced thickness to the steel
sheet. Unlike the original single-stand mills, a tandem mill rolls
steel through a series of rolls (generally three to five in a row)
to achieve a desired thickness and surface quality.
Teeming
Pouring; ingot
molds are filled (teemed) by iron-bearing ladles.
Temper Mill
A type of
cold-rolling mill, usually with only one or two stands, that
finishes cold-rolled, annealed sheet steel by improving the finish
or texture to develop the required final mechanical properties; By
changing the rolls of the temper mill, steel can be shipped with a
shiny, dull or grooved surface.
Terne
Sheet steel coated
with a mixture of lead and tin. Terne principally is used in the
manufacture of gasoline tanks, although it also can be found in
chemical containers, oil filters and television
chassis.
Tin Mill
Continuous
tin-plating facility to produce tin mill steel sheet to be used in
food and beverage cans and other containers.
Tin/Chrome Plating
A plating process
whereby the molecules from the positively charged tin or chromium
anode attach to the negatively charged sheet steel. The thickness of
the coating readily is controlled through regulation of the voltage
and speed of the sheet through the plating area.
Tin-Free
Steel
Chromium-coated steel. Because it is used in food cans just like tin
plate, it ironically is classified as a tin mill product. Tin-free
steel is easier to recycle because tin will contaminate scrap steel
in even small concentrations.
Tin Plate
Thin sheet steel
with a very thin coating of metallic tin. Tin plate is used
primarily in can-making.
Tolerances
A customer's
specifications can refer to dimensions or to the chemical properties
of steel ordered. The tolerance measures the allowable difference in
product specifications between what a customer orders and what the
steel company delivers. There is no standard tolerance because each
customer maintains its own variance objective. Tolerances are given
as the specification, plus or minus an error factor; the smaller the
range, the higher the cost.
Toll Processing
The act of
processing steel for a fee ("toll"). Owners of the steel sheet may
not possess the facilities to perform needed operations on the
material (or may not have the open capacity). Therefore, another
steel mill or service center will slit, roll, coat, anneal, or plate
the metal for a fee.
Tool Steels
Steels that are
hardened for the use in the manufacture of tools and
dies.
Ton -
Gross Ton.
2,240 pounds. Unit of measure for steel scrap and iron
ore-
- Short (Net) Ton. 2,000
pounds. Normal unit of statistical raw material input and steel
output in the United States.
- Metric Ton. 1,000
kilograms. 2,205 pounds or 1.102 short tons.
Trade Case
A type of lawsuit
filed by U.S. companies against their foreign counterparts in
response to imports at prices lower than those in the U.S. market.
Sanctions can be imposed by the International Trade Commission and
the Commerce Department on foreign producers involved in dumping and
government subsidization if domestic manufacturers can prove
material damage to their results.
Tubing
When referring to
OCTG, tubing is a separate pipe used within the casing to conduct
the oil or gas to the surface. Depending on conditions and well
life, tubing may have to be replaced during the operational life of
a well.
Tundish
The shallow
refractory-lined basin on top of the continuous caster. It receives
the liquid steel from the ladle, prior to the cast, allowing the
operator to precisely regulate the flow of metal into the
mold. Go back to the top
 
Vacuum Degassing
An advanced
steel refining facility that removes oxygen, hydrogen and nitrogen
under low pressures (in a vacuum) to produce ultra-low-carbon steel
for demanding electrical and automotive applications. Normally
performed in the ladle, the removal of dissolved gases results in
cleaner, higher-quality, more pure steel (see Ladle
Metallurgy).
Vacuum Oxygen
Decarburization (VOO)
Process for further refinement of stainless
steel through reduction of carbon content. The amount of carbon in
stainless steel must be lower than that in carbon steel or lower
alloy steel (i.e., steel with alloying element content below 5%).
While electric arc furnaces (EAF) are the conventional means of
melting and refining stainless steel, VOD is an economical
supplement, as operating time is reduced and temperatures are lower
than in EAF steelmaking. Additionally, using VOD for refining
stainless steel increases the availability of the EAF for melting
purposes. Molten, unrefined steel is transferred from the EAF into a
separate vessel, where it is heated and stirred by an electrical
current while oxygen enters from the top of the vessel. Substantial
quantities of undesirable gases escape from the steel and are drawn
off by a vacuum pump. Alloys and other additives are then mixed in
to refine the molten steel further.
Voluntary Restraint Agreements (VRAs)
A compromise reached between the U.S. government and
foreign steel-exporting nations. Instead of the United States
imposing punitive duties on subsidized steel imports, the foreigners
would "voluntarily" limit their steel exports to the United
States. Go back to the top
 
Walking Beam
Furnace
A type of continuous reheat furnace in which the billet or slab
moves through distinct heating zones within the furnace: By
controlling the speed through the zones, steelmakers can achieve
precise rolling temperatures and consume less fuel during
operation.
Wide-Flange Beam
A structural steel
section on which the flanges are not tapered, but have equal
thickness from the tip to the web and are at right angles to the
web. Wide-flange beams are differentiated by the width of the web,
which can range from three inches to over 40 inches, and the weight
of the beam, measured in pounds per foot.
Widths
The lateral
dimension of rolled steel, as opposed to the length or the gauge
(thickness). If width of the steel strip is not controlled during
rolling, the edges must be trimmed.
Work Rules
The division of
jobs into separate crafts and specify guidelines for work in the
labor contract. These provisions define the duties of a specific
job, and management must negotiate with the labor representative to
make any changes. Go back to the top
 
Yield
The ratio of the quantity of finished shipments to the total
raw steel produced, adjusted for changes in inventory and any slabs
that are purchased from outside. Yield has significantly improved
during the past decade, primarily as the result of the industry's
conversion to continually cast steel, whose yield is superior to
that of traditional ingot teeming.
Z-mill (See
Sendzimir Mill) Go back to the top
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