Back Drafting
Taking the blast furnace out of blast for short periods, often less than 2
hours, (instead of banking) to perform various maintenance functions such
as replacing tuyeres or repairing skip cables. This is done usually by
opening the chimney valve and the hot-blast valve to a stove that has
already been prepared by heating it to temperature and then shutting off
the gas valve. As the furnace gas is drawn back into the stove, air is
admitted through the peep sights and stove burner, and the operator makes
certain that the gas burns in the stove. During the operation, the bleeders
at the top of the furnace also are opened to pull some of the furnace gas
out through the top.
Heating after pickling /or pickling and coating to remove hydrogen.
Balanced Steel (Semi-Killed and Semi-Rimmed Steel)
Steel to which controlled amounts of deoxidizers have been added in the
liquid stage during tapping and teeming, the object being to reduce the
severity of piping. This steel is intermediate between killed and rimming
Refers to metal strap signode band that is one half inch wide. This band is
used to thread and pull the strip through the line.
Inhomogeneous distribution of alloying elements or phases aligned in
filaments or plates parallel to the direction of working.
Shutting down the blast furnace for few days. The blast is taken off, the
blowpipes are dropped and the tuyere openings are plugged with clay to
prevent air from drafting through. Thus, hearth heat is preserved and the
furnace can be returned to operation with a minimum effort.
Finished product of solid section generally supplied in straight length,
which are rolled from billets and may be rectangular, square, flats,
channels, round, half round or polygonal. The bars may be supplied in coil
form also. The dimensions generally conform to the following :
a. Rounds and Half-Rounds : Minimum diameter 5mm.
b. Squares and Polygonal : Minimum 6mm side.
c. Flat Bar (Flat) : A finished product, generally of cross section, with
edges of controlled contour and thickness 3mm and over, width 400mm and
below and supplied in straight lengths. The product shall have rolled edges
only (square or slightly rounded). This group also includes flat bars with
bulb that has swelling on one or two faces of the same edge and a width of
less than 400mm.
Bar Hold
The end of a bar or forging so reduced as to accommodate a porter bar or
tongs for manipulation during forging.
Bare Spot
A location on the strip where coating did not adhere.
The part of a forging of major cross section, the length of which usually
exceeds the diameter.
Basal Crack
A crack in the ingot base caused by restriction to free contraction during
Base Box
Unit of area of 112 sheets of Tin Mil products (tin plate, tin free steel
or black plate) 14 by 20 inches, or 31,360 square inches. Tin plate is
sold, and carried in finished inventory, on a weight per unit area rather
than on a thickness basis.
Base Metal Contamination
Dirt or other impurities in the steel strip.
Base Size
The intermediate size in which wire is annealed before drawing; in case of
drawn galvanised or drawn tinned wire, the size in which it is galvanised
or tinned.
Base Type
Type of base used for cooling; i.e., water or fan.
Base Weight
Tin Mill term; Thickness divided by .00011. Also weight in pounds of one
Base Box of tin plate. In finished inventory, base weight is specified
instead of decimal thickness.
Basic Flux
Used to remove unwanted acidic impurities to form a fusible slag. The chief
natural basic fluxes are limestone, composed primarily of calcium carbonate
(CaCO3), and dolomite, composed primarily of calcium-magnesium carbonate
(Ca, Mg)CO3.
Basic Oxygen Furnace (BOF)
What 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
Why BOFs, which can refine a heat (batch) of steel in less than 45 minutes,
replaced open-hearth furnaces in the 1950s; the latter 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. 
How 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.
Basic Oxygen Process (BOP)
A process in which molten steel is produced in a basic lined furnace by
blowing oxygen into molten iron, scrap and flux materials. The furnace is
known as Basic Oxygen Furnace (BOF).
Basic Process
A steel making process in which steel is refined under a basic slag in a
basic refractory lined furnace or convertor.
Basic Refractory
A refractory material basic in chemical composition and containing high
amounts of such oxides as lime and magnesia, for example, calcined dolomite
or magnetite.
Basic Steel
Steel made by basic process.
Basis Weight
See Base Weight.
Batch Anneal
The process by which a large, stationary stack of steel coils (4 coils
high) is subjected to a long heat-treating cycle. This process enables the
cold-rolled sheet to fully recrystallize into the softest possible product
conforming to customer specifications. Controlling the recrystallization
process makes a fine-grained microstructure easy to obtain, and minimizes
the tendencies for retention of directional properties of the rolled steel
which could produce undesirable shapes in the stamping of a cylindrical
part such as a can. Also see Anneal and Continuous Anneal.
Batch Pickling
Pickling of steel sheets and other light-gauge sheared lengths performed
with specialized equipment in which a batch of sheets are processed
together. Agitation of acid bath is employed as a means to increase the
pickling rate.
Bath Sample (Spoon Sample)
A sample taken from molten steel in the furnace, for estimation and
analysis of constituents.
Bead Test
Commonly used for testing coating adherence, especially on light-gauge
material. A bead is used to deform the steel such that the sample contains
a continuous ridge.
Forging the wall of a steel ring between a top becking tool and a becking
bar to increase the internal diameter with or without an increase in the
external diameter.
Belly Band
The band (strapping) that goes around the outside diameter of a coil.
Bench Drawn
Bars bright drawn in straight lengths on a draw bench.
Device used in drop forging hammer dies to bring the several sections of
the stock or prepared blank into alignment.
Bend Tests
Various tests used to assess the ductility of steel when subjected to
bending. Tests may include determination of the minimum radius or diameter
required to make a satisfactory bend and the number of repeated bends that
the material can withstand without failure when it is bent through a given
angle and over a definite radius.
Bessemer Process
A steel making process in which pig iron is refined in an acid refractory
lined convertor by blowing air or a mixture of air, carbon dioxide and
oxygen or steam through the molten metal. The basic process is known as
Thomas process.
Best Patented Steel Wire
Rope wire drawn to tensile strength of 128 to 147 kgf/mm2.
Best Plough Steel Wire
Patented rope wire drawn to a tensile strength of 155 to 170 kgf/mm2.
Refers to pipe; the end preparation for field welding of the joint.
lso BY-COIL. Tin Mill term. Customers buy "by coil" or "bi-coil" rather
than cut sheets.
A semi-finished steel form that is input material for manufacturing long
products: bars, channels or other structural shapes. A billet is different
from a slab because of its outer dimensions; billets are usually square and
not exceeding 125x125 mm in cross section with rounded corners, while slabs
are 750-1000 mm wide and 50-250 mm thick. Both shapes are generally forged
or continually cast or rolled in billet mill / slabbing mill from ingots,
but they may differ greatly in their chemistry.
Soft wire used for tying bundles or coil of wire.
Binders are used to impart strength to the refractory during manufacture or
in service. These are of 4 types : 
d. Temporary Binder : Their function is to improve handling strength
during manufacture. Temporary binders include paper byproducts, sugar, or
certain clays.
e. Chemical Binder : They impart strength during manufacture, after
manufacture, or on installation as a monolithic material. Chemical binders
include resins, starches, synthetic clays, waxes etc.
f. Chemical Binders : Chemical binders set hydraulically when mixed with
water. The primary binders of this type used in refractories are the
calcium-aluminate cements which set rapidly and are able to retain some of
their bonding strength to intermediate temperatures.
g. Organic Binders : Organic binders include tars, pitches, or resins for
use in reducing atmospheres where the carbon residuals impart bonding
strength or act to inhibit alteration.
Biological Oxidation
The most commonly applied technology for final treatment of coke plant
waste waters which have significant levels of phenol, cyanide, and ammonia,
plus lesser concentrations of other organic compounds, primarily as a
result of condensation from coke oven gases. The process consists of two
stages : in an aeration basin, a mass of microorganisms in the form of
suspended solids called an 'activated sludge' is supplied with oxygen,
which enables it to destroy the biologically degradable contaminants in the
wastewater. The treated water overflows to a clarifier, where the activated
sludge is settled out to be recycled back to the aeration basin. The
overflow water from the clarifier is discharged.
Bitumen Coating (Asphalt Coating)
An internal and / or external coating obtained either by dipping in a bath
of molten asphaltic bitumen or by painting or dipping in a suitable
asphaltic bitumen solution.
Bitumen Lining (Asphalt Lining)
An internal protection consisting of suitable bitumen, usually reinforced
with inert mineral filler, applied hot by centrifugal means.
Bitumen Sheathing (Asphalt Sheathing)
An external protection consisting of bitumen reinforced with inert mineral
filler which may be of a fibrous nature. The sheathing is applied hot.
Bituminous Solution
A paint made from bituminous materials dissolved in appropriate hydrocarbon
Black Annealing
Annealing without any protective covering or using a controlled atmosphere.
It is also termed as open annealing. Box annealing of ferrous alloy sheet,
strip or wire.
Black Edges
The black colouration at the edges of annealed sheets and strips caused by
oxidation or due to soot deposit.
Black Patches
Patches of scale left on sheet and strip surface due to unsatisfactory
Black Plate
1. Any steel that has not been coated – usually has gone through Tandem
Mill (cold-rolled). Also defines a product, uncoated material in tin plate
gauges. 2. 128 lb. (.0141 in) and lighter tin mill product which has not
received any additional metallic coating during production. 3. A low carbon
cold reduced steel intended for use in the uncoated state or for coating
with tin and chromium.
Black Iron
Uncoated steel product.
Black Sheet or Strip
Hot-rolled sheet or strip that is not descaled.
Black Softened
Hot- or cold-rolled sheet and strip softened by black annealing, but not
yet descaled (and usually refers to stainless variety).
Blank Holder
The device used to hold the blank to prevent wrinkling of the edges during
pressing or drawing.
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
Blast Furnace
A tall shaft-type furnace, with a vertical stack superimposed over a
crucible-like hearth, lined with heat-resistant (refractory) bricks and
used by integrated steel mills to smelt iron by reducing iron oxides
present in ores and sinter into liquid hot metal by using coke as fuel and
reducing agent. Its name comes from the blast of preheated air and gases
blown from the bottom through water-cooled copper tuyeres and forced up
through the iron ore, sinter, coke, and fluxes (limestone and dolomite)
that load the furnace. Hot metal and slag are periodically tapped from
bottom and gasses rising from the top are cleaned and used as fuel in the
steel plant. Blast furnaces are rarely stopped but they can be slowed down
or idled.
Blast Furnace Coke
The sized coke obtained from screening in the range of 25 mm to 80 mm which
is suitable for charging in the blast furnaces.
Blast Furnace Gas
A by-product of the iron blast furnace. 2.5 to 3.5 ton of BF gas is
generated per ton of the pig iron produced.
A process of cleaning or preparing surfaces by high speed impact of
abrasive particles, such as sand, chilled iron shot, or angular steel grit
(generally called sand blasting, shot blasting or grit blasting).
1. Escape of liquid steel through the bursting of the shell of a partly
solidified ingot due to build up of pressure inside the solidifying mass,
or escape of liquid from the core of an ingot, withdrawn from the mould
before it has solidified sufficiently. 2. A coating defect consisting of
the migration of an ingredient to the surface of a coating, or a migration,
which stains in an adjacent area. The term blooming is also a form of
bleeding – usually associated with lubricants rather than pigments.
1. Coating defect consisting of the formation of bubbles in a coating,
which appear as hemispherical elevations. The blisters are hollow, and are
usually caused by entrapped air or solvent. 2. A raised spot on the surface
on the surface of metal due to expansion of gas which causes a subsurface
metal separation such as inclusions and small laminations.
Block Drawn
Wire drawn in coil on a block.
Block Off
1. Wooden separators which are used at both the bottom of a lift and
between IPM's (bundles) of a lift. 2. The act of placing 4x4s between the
lifts in the piler's box.
A coating defect consisting of the adhesion of two adjoining coatings or
materials. Usually this term refers to the coating on one side of coated
plate being tacky or sticky and adhering to the adjacent sheet.
Bloom (1)
A semi-finished forged, rolled or continuously cast steel form whose
cross-section is square or rectangular (excluding slab) and is generally
more than 125 x 125mm (or equivalent cross-sectional area). This large cast
steel shape is broken down in the mill to produce the familiar I-beams,
H-beams and sheet piling. Reduction of a bloom to a much smaller
cross-section results in formation of billets. 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.
Bloom (2)
A coating defect consisting of the migration of an ingredient, in the
coating, to the surface of the cured film. Usually blooming refers to waxes
or lubricants, which rise to the surface and cause a hazy appearance.
Blow Back
A coating defect consisting of a lower coating film weight on the bottom of
the coated sheet caused by high velocity air in the oven. Blow back usually
occurs with high solids coatings which have little solvent to evaporate and
"set" the film.
Blow Hole (Gas Cavities)
Cavities in solid steel formed by entrapped gas bubbles during
Blowing Out
When a furnace has reached the end of its campaign (lining worn out), it is
usually blown out except under most unusual circumstances. Or, if business
conditions deteriorate to the extent production is no longer required, the
decision may be made to blow out the furnace.
Blown Ingot
An ingot with pronounced blow holes.
Blown Metal
Liquid pig iron which has been subjected to blowing in the converter, as a
result of which the iron is refined to the degree depending on requirement.
Blown metal is made into steel by addition of elements as required.
Blue Annealing
Heating hot rolled ferrous sheet in an open furnace to a temperature within
the transformation range then cooling in air to soften the metal. A bluish
oxide surface layer is formed.
Blue Annealed Wire
Wire with scale free surface, but oxidised to a blue temper colour during
Blue Billy (Purple Ore)
The iron oxide residue from the manufacture of sulphuric acid from iron
pyrites containing approximately 50% iron. It is used for fettling the
puddling furnace.
Blued Edges
Blue or bluish-black oxidation colouration at the edges of sheets and
strips arising during heat treatment in the absence of any protective
A coating defect consisting of the whitening of a cured film which results
in a translucent or opaque appearance with accompanying loss of gloss.
Blushing usually occurs during the pasteurization or steam processing of
films which are undercured or water sensitive.
Boiler Tubes (Smoke Tubes)
Tubes which form part of the heating surface of a boiler, as distinct from
superheater tubes. The tubes may contain water and be surrounded by the
furnace gases as in a water tube boiler, or they may act as flues and be
surrounded by water as in smoke tube boiler.
A dovetailed block of steel which rests on the base block of the hammer
into which the bottom die is keyed.
Treating cold rolled or galvanized steel surfaces with phosphate to improve
Bonderized Coating
A thin film of phosphate pretreatment applied to a steel surface (bare or
zinc coated) to enhance paintability.
A projection on the surface of a forging.
Reducing the diameter at the end of a hollow forging to form a neck.
Bottom Blowing
Injection of oxygen, singularly, with additives (such as pulverized lime)
or in addition to hydrocarbon fuels (such as natural gas, pulverized coke
or fuel oil), all routed in the same manner to initiate reactions in the
bath during oxygen steelmaking.
Bottom Casting (Trumpet Casting, Uphill Casting)
Simultaneous casting of a number of ingots by pouring the metal into a
central refractory-lined tube or trumpet, whence it flows through
refractory runners into the bottom of the moulds.
Bottom Fash (Bottom Flash, Bottom Fin)
A layer of metal in the space between the base of the mould and the bottom
plate which is attached to the ingot. Similarly, a layer of metal may be
formed at the top, in the space between the mould and the refractory lined
hot top, the layer of metal formed being called top flash.
Bottom Plate (Bottom Stool)
A cast iron plate of suitable size, on which the bottom of the mould (which
is open at both ends) sits. This plate may be recessed or refractory lined.
Bottom Splash (Bottom Shell)
The splash of metal solidifying on the bottom portion of a mould, and later
engulfed in the rising column of liquid steel, and arises from the impact
of the liquid steel on the bottom plate in initial stages of teeming.
Bottom Stirring
Injection of essentially inert gases into the bottom of the BOF vessel,
penetrating the bottom shell and the bottom refractory lining, under the
molten bath, to agitate the molten masses for such purposes as homogeneity
of the melt after introducing additions in the furnace and improving the
interaction between the steel bath and the slag. There is usually no direct
chemical reaction associated with bottom stirring. The gas injection is
either by means of refractory material porous plugs embedded in the bottom
lining, or by means of tuyeres, penetrating the bottom lining.
Box Annealing (Close Annealing)
A process of annealing a ferrous alloy in a suitable closed metal
container, with or without packing material, in order to minimize
oxidation. The charge is usually heated slowly to a temperature below the
transformation range, but sometimes above or within it, and is then cooled
The greatest deviation from a straight line along a longitudinal edge in a
sheet or strip.
Box Annealing
Annealing of a metal or alloy in a sealed container under condition that
minimise oxidation. See black annealing also.
Brake Press Bending
An operation which produces various degree bends when fabricating parts
from steel.
Cracks or separation of the steel.
Uncoiler rolls through which the strip passes; composed of a mandrel and
leveling rolls which unwind the strip prior to processing through the
Pickler. Breaker rolls assist in breaking up the Hot Mill surface scale.
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 and cause considerable damage to the furnace and
surrounding auxiliaries. The term is also used in continuous casting when
the solidified outer shell breaks-out resulting in liquid steel flowing-out
and spreading over the casting machine, jeopardising the entire casting
Breeze Coke
Smallest fraction of coke, less than 10 mm in size.
See Slips.
Bridle Unit
A three-roll cluster used to control line tension at strategic locations on
the line.
Bright Annealing
Annealing in a protective medium to prevent discoloration of the bright
Bright Annealed Wire
Wire which has been annealed in a controlled atmosphere to prevent surface
Bright Bar or Wire
Bar or wire with a bright finish obtained by cold drawing, machining,
grinding etc.
Bright Ground
Bar or wire ground between abrasive wheels which give a bright finish to
the material.
Bright Machined
Material which has been turned, ground, shaped or milled to size and
finished with a smooth bright surface.
Bright Turned Rounds
a. Round hot rolled material which has been reduced in size by centreless
turning and finished with a smooth bright surface
b. Round hot rolled material which has been turned between centres and
finally finished. Turned material is generally cold rolled to remove tool
Brinell Hardness Test
A test for determining the hardness of a material by forcing a hard steel
or carbide ball of specified diameter into it under a specified load. The
result is expressed as the Brinell hardness number.
Briquette Blending
Using non-coking or poorly coking coals by partially briquetting them with
coking coals (and binder i.e. tar or pitch) to produce high-strength coke.
1. Regular galvanize coating (not minimized spangle or JP).
2. Rolls that have no grit; smooth finish on surface of steel.
Brittle Fracture
Separation of a solid accompanied by little or no macroscopic plastic
deformation. Typically, brittle fracture occurs by rapid crack propagation
with less expenditure of energy than for ductile fracture.
Brittle Inter-metallic Layer
An iron-zinc alloy layer formed between the steel substrate and the free
zinc of galvanized coatings.
Tendency to fracture without any visible sign of appreciable deformation.
Broken Backs
A band of traverse cracks along a drawn wire.
A mark transferred to the strip surface from a defective process roll.
Similar to dent or punchmark.
See Butyl Stearate.
A compression phenomenon that occurs when, after some critical level of
load, a bulge, bend, bow, kink, or other wavy condition is produced in a
beam, column, plate, bar, or sheet product form.
Build Up Coil
A coil made by putting together two or more coils to make one max coil or
one shippable coil.
Specific number of sheets which equals 1 unit of production. Number is
determined by multiplying sheets/Packages/Bundle. For example, an order
calls for 112 sheets/package according to the maximum height allowed for a
lift. Therefore, multiplying 15 packages X 112 sheets = 1680 sheets/bundle.
The regulation of the proportion of ore, pellets, sinter, flux, coke and
miscellaneous materials charged into the blast furnace. Essential to keep
the operation of the furnace at maximum efficiency and to control the hot
metal composition.
Burden Ratio
In blast furnace, the ratio of iron-bearing materials per charge to the
weight of coke.
Burned Steel
A defect on the surface of the ingots, usually on their corners, as a
result of flame infringement as they are heated in the soaking pits.
(1) During austenitising, permanent damage of a metal or alloy by heating
to cause incipient melting or intergranular oxidation.
(2) During subcritical annealing, particularly in continuous annealing,
production of a severely decarburised and grain coarsened surface layer
that results to excessively high temperature.
(3) In grinding, sufficient heating of the workpiece to cause discoloration
or to change the microstructure by tempering or hardening.
Burnt Edges
Broken edges occurring during hot-rolling and caused by overheating or
Burnt Rubber
Small or large black spots that generally show up on surface and are
generally caused by pickling steel too hot.
Burr (Fash, Flash)
The very subtle ridge on the edge of strip steel left by cutting operations
such as slitting, trimming, shearing, sawing 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).
Burr Mashers
Devices used to remove build up on edge of strip after the slitting
Burst Edges
Edges of sheet or strip ruptured due to excessive cold rolling.
1. Steel scrap consisting of sheet clips and stampings from metal
production. This term arose from the practice of collecting the material in
bushel baskets through World War II. 
2. Compacting wrought iron turnings, borings and scrap into a bloom or slab
by heating to a welding temperature and forging.
Rotating disc-type valve which moves 90o from the closed position to the
fully open position. Normally used to stop or control the flow through a
line, the butterfly regulates steam on the plant service line.
Butt Weld
Weld made to join two strip ends set against each other.
Butt Welding
Joining two edges or ends by placing one against the other and welding
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.
Butyl Stearate (BSO)
A lubricant applied on electrolytic chromium coated steel.
By Coil
Selling term which refers to product sold in the form of a coil vs. cut
plate. "Bi Coil" is also used in production to refer to coils vs. cut
By-Product Process of Coke Making
In this process, air is excluded from the coking chambers, and the
necessary heat for distillation of coal is supplied from external
combustion of some of the gas recovered from the coking process (or, in
some instances, cleaned blast furnace gas or a mixture of coke oven and
blast furnace gas).
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