Difference of Grades
There are three grades of steel
Bar end of Grade 60 will be marked with yellow paint
Grade
|
Grade
|
Minimum Yield Strength
|
|
|
in pounds
|
in
|
inch-pound
|
metric
|
per square inch
|
megapascals
|
| Grade 40 | Grade 280 | 40,000 | 280 |
| Grade 60 | Grade 420 | 60,000 | 420 |
| Grade 75 | Grade 520 | 75,000 | 520 |
For the grades 60 & 75 the bar will be marked
Grade
|
Metric grade
|
Continuous line system
|
Number system
|
|
|
number stamped onto bar
|
60
|
420
|
1 line running the length of the bar
|
60
|
4
|
offset at least five spaces from the center of the bar
|
75
|
520
|
2 lines running the length of the bar
|
75
|
5
|
offset at least five spaces from the center of the bar
|
Semi Finished
Slabs: Steel slabs are hot-rolled from an ingot or strand cast. They are wide and rectangular in shape.
They are used for the manufacture of all 'flat' steel products such as coils, sheets, strip, plates and other flat-rolled steel products.
Billets
Steel billets result from the second stage of the steel production process. They are hot-rolled or forged from an ingot or strand cast. Smaller and longer than a bloom, billets are usually a square cross section less than 36 square inches.
They are used for the manufacture of all 'long' steel products such as bars, rods, pipes, tubes, wire and wire products.
Blooms
Blooms are hot-rolled or forged from an ingot or strand cast. They usually have a square cross section exceeding 36 square inches.
They are mainly used in the manufacture of ‘long’ products such as structural shapes, structural profiles, building beams, rails and columns.
Flat
Hot Rolled Coil (HRC)
Hot rolled coil is rolled on a hot strip mill from slabs. It can be found on the market in coil or sheet form and is further processed into finished products by the manufacturer. Hot rolled coil is typically 2-25mm thick and up to 2,250mm wide.
Hot rolled coil is produced as a feedstock for cold rolled coil and coated coil, but also for direct use in a variety of industrial applications including steel tubes used in transport, construction, shipbuilding, gas containers, pressure vessels and energy pipelines. Hot rolled sheet with an anti-slip surface and a diamond or teardrop pattern is typically used for stairs, industrial floors and tailboards for goods vehicles.
Cold Rolled Coil (CRC)
Cold rolled steel is a 'flat' steel product. The material is manufactured from hot rolled steel, the thickness of which is further reduced on a strip mill without the use of heat. The resulting thinner and flatter material is known as cold rolled steel. Typical thickness is from 0.15 to 3 mm. Typical width is from 600 to 2,100 mm.
Finished cold rolled steel coil has excellent forming properties, electromagnetic properties, paintability and weldability It is suitable for fabrication by forming, pressing and bending. Applications include domestic applications, automotive manufacturing, lighting fixtures, electrical components (stators, rotors), various kinds of sections, roofing applications, profiled sheets, and wall elements.
Hot Dipped Galvanised Coil / Sheet
Obtained by passing cold rolled coil through a molten zinc bath, in order to coat the steel with a thin layer of zinc to provide corrosion resistance. Hot dipped galvanized coil can be found on the market in coil or in sheets and is further processed into finished products by the manufacturer. Typical thickness is from 0.3 to 3 mm. Typical width is from 600 to 2,100 mm.
Hot dipped galvanized coil has excellent forming properties and is suitable for fabrication by forming, pressing and bending. Applications include domestic appliances, building applications (e.g. wall elements, roofing, automotive parts (e.g. underbody), lighting fixtures, drums and various kinds of sections and profiled sheets.
Hot Rolled Plate
Hot rolled plate is produced by hot rolling a steel slab to form a plate. Typical thickness is between 2 to 20mm and maximum width is 1860 mm.
The material is used in the shipbuilding, pressure equipment and construction industries.
Cold Rolled Sheet
Flat rolled products for which the required final thickness has been obtained by rolling at room temperature. To meet the various end use requirements, cold-rolled sheet products are metallurgically designed to provide specific attributes such as high formability, deep drawability, high strength, high dent resistance, good magnetic properties, enamelability and paintability.
Cold rolled steel sheet is used in a wide variety of end applications such as appliances refrigerators, washers, dryers and other small appliances, automobiles - exposed as well as unexposed parts - electric motors, and bathtubs.
Tin Plate
Tinplate is cold reduced steel sheet coated with a thin layer of tin. Tin mill products are produced in a variety of types including electrolytic tinplate, electrolytic chromium coated steel and black plate, an uncoated product. It has good corrosion resistance and food compatibility – although many products require a thin coating of lacquer to maximise the shelf life of the contents.
Around 90% of tinplate is used in packaging, with food and drinks cans the biggest market, but it is also widely used for other consumer and general packaging, such as aerosols, paints and oils.
Coated Sheet
Coating steel sheet improves durability and lengthens product life. It is manufactured to meet specific customer requirements for corrosion resistance, strength and formability. Thickness, width, surface quality and surface finish vary greatly.
The most typical applications are for metal roofing and automotive manufacturing.
Coated Steel Coil
Colour coated, or pre-painted, steel, is steel coil to which a paint, powder or film coating has been applied in a continuous process prior to it being cut and shaped. It provides a durable uniform surface finish, and can be an alternative to conventional post-manufacture painting of steel parts. The coil is coated on one or both sides. Rolls apply first a primer and then a topcoat to the moving steel strip. The substrate is usually cold reduced galvanised coil, but galvanised HRC and even uncoated coil is used.
Building applications account for around two thirds of consumption, with cladding on steel frame buildings a well known use. It is also widely used for domestic appliance casings and for some furniture.
Reinforcing Bar
Reinforcing bar (or Rebar) is formed from a steel billet, normally having surface deformations for use in reinforcing concrete. The bar can be produced in straight lengths as well as coiled.
Rebar is used in the construction industry to reinforce concrete.
Merchant Bar
Merchant bar is a range of commodity carbon steel long products including round, square and hexagonal bars, angles, channels and flats. Maximum diameter or width is usually 80-100mm, although flats up to 150mm wide are included. These are a staple item for many steel stockholders, large or small.
Merchant bar is widely used in the manufacture and fabrication of a broad range of engineered products.
Structural Sections
Heavy or structural sections are steel products such as beams or columns which are usually formed with a specific cross section shape e.g. H, I or U.
Used to build large structures such as multi-storey buildings and bridges.
Wire Rod
Hot rolled from steel billet, wire rod is delivered as coil, most commonly at 5.5mm dia, but in sizes up to 60mm dia. Close control of final cooling is a critical part of production. The most important characteristic for determining a rod's end use is its drawability; the extent to which the rod's diameter can be reduced during the drawing process.
Engineering Steels
Engineering steels, or special bar quality (SBQ), is used to describe steel long products for more demanding processing or end-use applications than can be met by commodity grades. Products include bright bars, rolled carbon and alloy bars, forged, tool and stainless steels. These are generally machined, forged or cold drawn during subsequent processing.
The main application area is the automotive industry for engine, transmission, steering and suspension components, but engineering steels are also used for a wide range of industrial applications including hand tools, oil & gas exploration and wind turbine components.
Forgings
Forgings are used in a variety of mechanical applications in heavy industries such as mining, construction and oil & gas exploration.
Seamless Tubes
Boiler tubing, the oil and gas industries and automotive transmission components are typical applications.
Welded Tubes
Welded tubes are made from hot rolled or cold reduced strip, sheet or plate.
Welded tubes are used in a wide range of general engineering applications as well as in power generation plants, oil refineries, automotive manufacturing and furniture production.
Stainless Steel
Stainless steel is the generic name for a number of different steels used primarily for their resistance to corrosion. The one key element they all share is a minimum percentage of chromium: 10.5%. Although other elements are added to improve corrosion resistance, chromium is always present. The principal grades are austenitic (typically 16-26%Cr, 6-22Ni); ferritic (10.5-28%Cr with no/low Ni); martensitic (higher carbon content than ferritic and typically 12-19%Cr with low/no Ni); and duplex, a dual-phase austenitic/ferritic steel (Cr>21%, Ni <8%).
Its many varied applications include food production and storage equipment, pumping and storage of oils, gases and acids, specialist components in the automotive industry, cutlery, surgical instruments and fasteners.
