An alphabetical list of terms, with explanations.

  • A & P

    Annealed and Pickled.

  • Acid Brittleness

    Brittleness caused by pickling in dilute acid to remove scale.

  • Acid Steel

    Steel melted in a furnace having an acid bottom and lining and under a slag with acid reaction.

  • Actual Size

    The real measurement for either the Inside Diameter or the Outside Diameter of the pipe.

  • Aging

    The process or sometimes the effects of allowing metal to remain at ordinary temperatures or in heat treatment at tempera­tures above normal to hasten changes that take place in normal aging.

  • Alloy Elements

    Elements added to improve or change prop­erties of the metal.

  • Annealing

    A heating and cooling operation, usually slow cooling, performed on steels in the solid state.
    Annealing is a comprehensive term, the purpose of which maybe:
    (1) To remove stresses.
    (2) To induce softness.
    (3) To alter ductility, toughness, electrical, magnetic or other physical properties.
    (4) To refine the crystalline structure
    (5) To remove gases.
    (6) To produce a definite microstructure.

  • Av.


  • B & O

    Blued and Oiled

  • Basic Steel

    Steel melted in a furnace with a basic bottom and lining and under a slag having a basic reaction.

  • Bessemer Process

    A steel making process in which air is blown through the molten iron so that the impurities are thus removed by oxidation.

  • Billet

    A rectangular semi-finished rolled ingot of from 4 to 36 square inches in cross section, with a width less than twice the thickness.

  • Binary Alloy

    An alloy having two principal elements.

  • Black Annealing

    A method of annealing sheets or other products, used when it is not important that the product be free of scale discoloration.

  • Blue Annealing

    A method of annealing sheets which gives them a bluish-black color. The heavier gauges are allowed to cool slowly after rolling: the lighter ones are passed singly through an open furnace to bring them to the proper annealing temperature.

  • Blue Brittleness

    Brittleness occurring in steel at 413 to 700°F or after cooling when worked at these temperatures.

  • Box Annealing

    Annealing steel by heating in a closed metal box which protects it from oxidation.

  • Bright Annealing

    Annealing clone in closed containers with a reducing atmosphere which prevents the oxidation and discolora­tion of the surface.

  • C & S

    Cut and Straightened.

  • C.D.

    Cold Drawn.

  • C.F.

    Cold Finished.

  • C.R.

    Cold Rolled.

  • Carbon Steel

    Steel which derives its properties from various percentages of carbon without any great amount of other alloying elements.

  • Carburizing

    A case hardening process by which carbon alone is added to a limited or specified penetration by heating steel below its melting point in contact with carbonaceous solids, liquids, or gases.

  • Case

    The surface area of an iron-base alloy whose carbon content has been increased substantially by case hardening.

  • Case Hardening

    Carburizing and subsequently hardening by suitable heat-treatment, all or part of the surface portions of a piece of iron base alloy.

  • Chipping

    Removing seams and other surface defects from steel by means of hand or power chisels.

  • Cleavage Plane

    Planes along which crystals break more easily.

  • Cogging

    Reducing ingots to blooms by rolling or forging.

  • Cogging Hammer

    Forging hammer for reducing ingots to blooms.

  • Cold Shortness

    The characteristic of metals that are brittle at ordinary or low temperatures.

  • Cold Shut

    A place in metal where two portions of the metal in either a molten or plastic condition have come together but have failed to unite into a solid mass.

  • Cold Working

    The operation of forming the metal, without the application of heat, by rolling, hammering, drawing, pressing or other means to obtain accurate size, fine finish or increased strength.

  • Conduit

    Pipe serving as a duct for electrical wiring; usually supplied in ten-foot lengths, with plain ends or threaded and coupled. The pipe used is normally galvanized, slightly larger than standard weight with a smooth inner surface. However, the term “conduit” may refer to pipe for uses other than electrical.

  • Core

    The interior portion of an iron-base alloy whose chemical composition has not been substantially changed as the result of case hardening.

  • Crop

    The defective ends of a rolled or forged product which are cut off and discarded.

  • Cup Fracture

    A type of fracture in a tensile test specimen which looks like a cup having the exterior portion extended with the interior slightly depressed.

  • Cyaniding

    Surface hardening of an iron base alloy article or portion of it by heating at a suitable temperature in contact with a cyanide salt, followed by quenching.

  • D & S

    Dehydrated and Sealed.

  • Decarburization

    A metallurgical process in which the surface of steel is depleted of carbon, by heating above the lower critical temperature or by chemical action.

  • Differential Heating

    Heating so that various portions of an article reach different temperatures in order that different properties will be produced upon cooling.

  • Drawing

    Reheating after quenching for hardening, to some temperature below the lower limit of the critical range, followed by cooling as desired.

  • Effect of Boron on Steel

    Increases hardenability of lower carbon steels – up to 0.008% maximum boron content. Has improved machinability, as well as hot and cold working characteristics over standard alloy steels.

  • Effect of Carbon on Steel

    Increasing the carbon content increases the tensile strength and hardness.

  • Effect of Chromium on Steel

    Increases hardenability, resistance to corrosion and oxidation, abrasion and high temperature strength.

  • Effect of Copper on Steel

    Used to increase atmospheric corrosion resistance, and sensitivity to both cold and hot shortness.

  • Effect of Manganese on Steel

    Manganese is added in the making of steel to prevent red shortness and increase hardenability.

  • Effect of Molybdenum on Steel

    Increases hardenability and coarsening temperature. Raises the creep strength and red hardness, and enhances corrosion resistance of stainless steel.

  • Effect of Nickel on Steel

    Strengthens and toughens ferrite and pearlitic steels, and renders high chromium alloy steels austenitic (stainless steels).

  • Effect of Phosphorous on Steel

    Produces brittleness and general cold shortness. Strengthens low carbon steel, increases resistance to corrosion, and improves machinability.

  • Effect of Silicon on Steel

    Used as a general purpose deoxidizer. Strengthens low alloy steels and increases hardenability. Used as alloying element for electrical and magnetic steels.

  • Effect of Sulphur on Steel

    When sulphur is over .06 there is a tendency to red shortness. Free cutting steel, for threading and screw machine work, is obtained by increasing sulphur content to about .075 to .10.

  • Effect of Vanadium on Steel

    Elevates coarsening temperatures, increases hardenability, and is a strong deoxidizer.

  • Elastic Limit

    The greatest stress a material is capable of developing without a measurable change remaining after complete release of the stress. To determine the elastic limit, a load is applied to a specimen at a uniform rate, and the stress at which the specimen suddenly elongates is recorded on an “extensometer”, reading to 0.0002 inch, which is attached to the specimen to indicate distance between gauge marks.

  • Endurance Limit

    Maximum stress to which material may be submitted without causing fatigue failure.

  • Eutectoid Steel

    A steel consisting of nothing but pearlite (about .90 carbon).

  • Ex.


  • F.C.

    Free Cutting.

  • F.T.

    Free Turning.

  • Ferro Alloys

    Iron alloyed with some element such as manganese, chrome, or silicon, etc., used for adding the element to steel.

  • Fiber

    A fiborous or woody appearing structure found in fractures of wrought metal, and generally indicating directional properties.

  • Fiber Stress

    Unit stress at a section over which the stress is not uniform.

  • Finishing Temperature

    Temperature at which the hot working is finished.

  • Flash

    A fin of metal formed on the sides of a forging when the metal is forced out between the edges of the forging dies and which does not unite with the parent metal.

  • Forging Strains

    Strains caused by forging or by cooling after forging.

  • Fracture

    The surface of a broken piece of metal.

  • Fracture Test

    Breaking metal to determine structure composition of physical condition by examining the fracture.

  • Full Annealing

    Heating to above the critical temperature range followed by slow cooling through the range.

  • Grain Growth

    Increase in grain size.

  • Grains

    Metal crystals.

  • Granulation

    The formation of grains immediately upon solidification.

  • Graphitizing

    Graphitizing is a type of annealing of cast iron whereby some or all of the combined carbon is transformed to free or uncombined carbon.

  • H.D.

    Hard Drawn.

  • H.F.

    Hot Finished.

  • H.H.

    Half Hard.

  • H.R.

    Hot Rolled.

  • Hardening

    A Heat Treating Process that implies heating steel to a temperature above the critical range, and cooling it rapidly enough through the critical range to harden it appreciably.

  • Hardness Tests

    (a) Brinell Hardness – A hardness test performed on a Brinell hardness testing machine. The smooth surface of a specimen is indented with a spherical-shaped hardened steel ball of known diameter by means of a predetermined load applied to the ball. The diameter of the impression is measured in millimeters with a micrometer microscope, and the reading is compared with a chart to determine the Brinell Hardness number (Bhn).
    (b) Rockwell Hardness – A hardness test performed on a Rockwell hardness testing machine. Hardness is determined by a dial reading which indicates the depth of penetration of a steel ball or diamond cone when a load is applied.
    (c) Scleroscope or Shore Hardness – A hardness test performed on a Shore Scleroscope Hardness Tester. The hardness is determined by the rebound of a diamond pointed hammer (or tup) when it strikes the surface of a specimen. The hammer (or tup) is enclosed in a glass tube and the height of the rebound is read either against a graduated scale inscribed on the tube, or on a dial, depending on the model instrument used.

  • Heat Treatment

    Metal or alloy is heat treated to improve it for the service intended or to prepare it for operations such as cold rolling, cold drawing or machining. This process is broadly defined as an operation or combination of operations involving the heating and cooling of metal or alloy in the solid state to obtain a certain desired condition or set of properties.

  • Hex.


  • Hot Shortness

    Brittleness in hot metal.

  • Hot Working

    The operation of rolling, hammering, pressing or extruding metal which has been made plastic by heating.

  • Hvy.


  • Hypereutectoid Steel

    Steel with less than the eutectoid percentage of carbon.

  • Impact Test

    A method of testing specimens to determine resistance to blows or shock.

  • Ingot

    A casting for subsequent rolling or forging.

  • Ingot Iron

    Open hearth iron low in carbon, manganese and other impurities.

  • Killed Steel

    Molten steel held in a laddle or furnace until all the gas has gone out and the metal is quiet.

  • Lap

    A seam over fins or sharp comers in hot metal and then rolling or forging them into the surface.

  • Lap Weld

    Weld made on overlapped edges of scarfed or beveled skelp to form tubing or pipe.

  • Macrostructure

    The structure of ground or polished sample revealed by slight magnification or the naked eye.

  • Malleablizing

    Malleablizing is a type of annealing operation with slow cooling whereby combined carbon in white cast iron is transformed to temper carbon and in some cases the carbon is entirely removed from the iron. Note: Temper carbon is free carbon in the form of rounded nodules made up of an aggregate of minute crystals.

  • Matrix

    The main substance in which a constituent substance is embedded.

  • Mechanical Working

    Changing the former structure of a metal by subjecting it to pressure by rolling, pressing, or forging. The crystalline structure is refined and the quality of the metal is improved as the particles are forced into intimate contact. The strength is always increased by working and the hardness and ductility may be affected depending upon the amount of work done and by the temperature at which the working is carried on.

  • Modulus of Elasticity

    Within the limits of elasticity the M.E. is the ratio of the load applied to the corresponding movement caused by the load.

  • Network Structure

    A structure in which the crystals of one constituent are surrounded by envelopes of another constituent which gives a network appearance to an etched test specimen.

  • Nitriding

    A process by which nitrogen alone is added to a limited or specified penetration by heating certain alloy steels, which have a properly conditioned surface, in contact with ammonia gas or other substance from which the steel may absorb nitrogen. This produces an extremely hard, wear-resistant surface.

  • Normalizing

    The normalizing process is applied to steel to restore its normal condition after hot working, cold working, or non-uniform cooling, or to efface the effects of a previous heat treatment. Normalizing is accomplished by heating to a temperature about 100° F. above the critical range and then cooling in still air at room temperature.

  • Overheating

    Heating to such a temperature that while the properties of the metal are impaired, it has not been burned and can therefore be restored by heat treatment.

  • Patenting

    Heating to above the critical and cooling in air or molten lead at a temperature of about 700° F.

  • Percentage of Elongation

    The percentage of increase in length of a tension test specimen after rupture.

  • Percentage Reduction of Area

    The percentage of decrease of cross-sectional area of a tension test-specimen after rupture.

  • Pickling

    Removing scale by immersion in a dilute acid bath.

  • Plate

    Carbon steel plate comprise that group of flat rolled finished steel products within the following size limitation:
    .0180 in. or thicker, over 48 in. wide
    .0230 in. or thicker, over 6 in. wide
    7.53 lb./ sq. ft. or heavier, over 48 in. wide
    9.62 lb./ sq. ft. or heavier, over 6 in. wide

  • Preheating

    (1) A general term used to describe heating applied as a preliminary to some further thermal or mechanical treatment. (2) A term applied specifically to tool steel to describe a process in which the steel is heated slowly and uniformly to a temperature below the hardening temperature and is then transferred to a furnace in which the temperature is substantially above the preheating temperature.

  • Process Annealing

    Heating to a temperature below or close to the lower limit of the critical and then cooling.

  • Proportional Limit

    See Elastic Limit.

  • Psl

    Product Specification Level.

  • Pspe

    A hole or cavity formed in ingots when the metal solidifies.

  • Quaternary Alloy

    An alloy having four principal elements.

  • Quenching

    Cooling by immersion in some medium, which may be any liquid or gas, or even a solid in suitable form, to absorb heat rapidly from the article to be quenched.

  • Random Lengths

    Lengths can be specified, but, if random lengths are permitted, cutters have a spread from 2 to 5 feet,depending on ordered length and size.

  • Red Shortness

    Brittleness in red hot steel.

  • Reduction of Area


  • Refining Temperature

    Brittleness in steel when it is red hot.

  • Regenerative Quenching

    The difference between the original cross sectional area and that of the smallest area at point of rupture. It is usually stated as a percentage of the original area.

  • Rimmed Steel

    Temperature at which the grain size and structure of the steel is refined, usually just above Ac3.

  • Scale

    Double quenching carburized parts to refine case and core.

  • Scarfing

    By control of analysis, temperature, etc. if is possible to produce a steel which when poured into molds will partly deoxidize itself on the surface which is in contact with the mold. This type of deoxidation or killing leaves a surface of almost pure iron and drives the other constituents and impurities towards the center of the ingot. When such aft ingot is sectioned and etched the skin or rim shows up plainly and thus the name “rimmed steel” was suggested. Rimmed Steel is usually under 0.25 carbon and low in silicon and manganese, and is largely used for the production of soft wire, sheets, etc.

  • Schedule Numbers

    An oxide of iron which forms on the surface of hot steel. Sometimes it forms in large sheets which fall off when the steel is rolled.

  • Seam

    Cutting surface areas of metal objects, ordinarily by using a gas touch. The operation permits surface defects to be cut from ingots, billets, or the edges of plate that is to be beveled for butt welding.

  • Seam Annealed

    ANSI numbers assigned to pipe depending upon wall thickness (Becoming obsolete).

  • Self-hardening Steel

    A crack caused by a blowhole or other defect which has been closed but not welded.

  • Semi-steel

    Heating a weld seam to a temperature slightly below the point at which grain structure is effected (known as the critical temperature), followed by cooling in still air. This reduces weld hardness without changing the grain structure.

  • Shore Hardness

    An alloy tool steel that hardens when cooled in air and which will hold a cutting edge at temperatures nearing a light red.

  • Skelp

    Steel of an intermediate carbon range between iron and steel.

  • Slab

    The reading of a conventional scale determined by the rebound of the hammer of the Shore scleroscope on striking the surface of the specimen.

  • Slabbing Mill

    Steel that is the entry material to a pipe mill. It resembles hot-rolled strip, but its properties allow for the severe forming and welding operations required for pipe production.

  • Soaking

    The most common type of semi-finished steel. Traditional slabs measure ten inches thick and 30-85 inches wide (an 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 and plate products.

  • Solidification Range

    Heavy plate mill.

  • Spalling

    Holding steel at fixed temperature long enough for a complete uniform penetration of the heat.

  • Spheroidizing

    Temperature at which metal solidifies.

  • Stencil

    Cracking and flaking of the metal surface.

  • Stress Relieving

    Prolonged heating of iron base alloys at a temperature in the neighborhood of, but generally slightly below, the critical temperature range, usually followed by relatively slow cooling.
    Note a — In the case of small objects of high carbon steels, the spheroidizing result is achieved more rapidly by prolonged heating to temperatures alternately within and slightly below the critical temperature range.
    Note b — The object of this heat treatment is to produce a globular condition of the carbide.

  • Stretch Reduction

    Paint spray identification placed on pipe. Specification, size, wall, grade, test pressure, method of manufacture and normal mill characters and mill identification are usually included; however, detail varies by specification. “Made in USA” is included.

  • T&C

    A process of reducing residual stresses in a metal object by heating the object to a suitable temperature and holding for a sufficient time, and cooling slowly. This treatment may be applied to relative stresses induced by casting, quenching, normalizing, machining, cold working or welding.

  • TBE

    Property of absorbing considerable energy before fracture; usually represented by the area under a stress-strain curve, and therefore involving both ductility and strength.

  • Temper Carbon

    Threaded and Coupled.

  • Tempering (also termed drawing)

    Threaded Both Ends.

  • Tempering or Drawing

    Graphite produced by heating at a temperature below the melting point.

  • Tensile Strength

    Reheating, after hardening to some temperature below the critical temperature range followed by any rate of cooling.
    Note a — Although the terms “tempering” and “drawing” are practically synonymous as used in commercial practice, the term “tempering” is preferred.
    Note b — Tempering meaning the operation of hardening followed by reheating IS a usage which is illogical and confusing in the present state of the art of heat treating and should be discouraged.

  • Ternary Alloy

    This process is applied to relieve stresses due to hardening and to adjust the hardness to the value desired. The hardened steel is reheated to a temperature below the lower critical range and is then permitted to cool.

  • Toughness

    The maximum load, per unit of original cross-sectional area, a material in tension is capable of withstanding before complete failure or rupture. As known as ultimate tensile strength.

  • Turn

    Alloy having three principal elements.

  • Ultrasonic

    Property of absorbing considerable energy before fracture; usually represented by the area under a stress-strain curve, and therefore involving both ductility and strength.

  • Vic-Victaulic

    A nondestructive testing method of detecting, locating, and measuring both surface and subsurface defects in metals with the use of high frequency sound.

  • Victaulic

    A work shift in the mill of usually 8 hours duration.

  • Wall-Heavy

    Registered trademark of Victaulic Corp. of American.

  • Wall-Thin


  • Work Hardness

    Wall thickness less than the specified minimum wall thickness called for by the pipe standard designated in the purchase order specifications.

  • Yield Point

    Wall thickness less than the specified minimum wall thickness called for by the pipe standard designated in the purchase order specifications.

  • Yield Strength

    Hardness resulting from mechanical working.