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    Aluminium sheets, plates and coil.Aluminium Trading supplies aluminium sheets, plates and coil to hundreds of industries throughout Southern Africa each month. The metals strength, superb corrosion resistance and light-weight structure make it a very popular material to work with to meet the modern and intricate demands of today’s world. In fact, Aluminium has become the second most used metal on the planet after iron/steel. But a very common question we still receive is “What are the differences between aluminium sheets, plates, and coil?”
    When looking at the three types of aluminium products, the only difference is the thickness. The thickest product being aluminium plate followed by sheet and finally, coil being the thinnest. However, the exact thicknesses separating each category depends on a few factors. Metals, in general, have been differently classified for thickness depending on the metal, the gauge, and even the application.

    Historical Metal Standards – Inconsistent?

    Before the development of modern, accurate measurement devices and technology, ‘gauges’ were the standards used to classify the thickness of metals, wires in particular. Over time, each metal industry formed its own independent standards. This resulted in gauge numbers that vary for aluminium, copper, brass and the many different variants of steel. An example of this can be seen in the Dictionary of Units of Measurement. This publication defines 10-gauge aluminium as being 0.259 centimetres thick, while 10-gauge standard steel is 0.341 centimetres and a 10-gauge galvanized steel is 0.351 centimetres.

    Due to the confusion caused by the gauging system, the American Society for Testing and Measurement (ASTM) stated in specification ASTM A480-10a; ‘The use of gage numbers is discouraged as being an archaic term of limited usefulness not having general agreement on meaning’.

    Modern Measurements for Metal Thickness

    Today it has become common practice to simply specify an exact thickness for any given product. Although gauges are still listed in the United States, South African and European industries have used the term less and less frequently in recent years.

    In terms of aluminium and its alloys in South Africa, there is still a bit of uncertainty over the exact thickness of the metal in classifying it as either sheet, plate or coil, with most distributors and fabricators deciding these classifications by themselves. At Aluminium Trading we provide aluminium plate with a thickness greater than 4.5mm, aluminium sheet with a thickness of 0.5mm – 3mm, aluminium coil with a thickness of 0.5mm to 0.6mm and foil with a thickness of approximately 0.29mm.

    To demonstrate the difference in thickness amongst different distributors we contacted Mr Kent Bell, a Market Manager at Hulamin South Africa, and asked for their classifications on aluminium thicknesses. Hulamin specialises in rolled aluminium products for precision and high technology applications, and are one of the largest producers of rolled aluminium products in Africa.

    Coated Steel: Resistant, Useful, and Aesthetic
    Coated steels are steel sheets that have a metallic and/or non-metallic coating to prevent rust and corrosion that humidity and contamination can cause on the steel.

    Coated steel has an extra layer of metal, paint, or both to protect it from rust and wear. It is ideal for those who are looking for resistant, aesthetic, light, and cost-effective materials in industries such as construction, automotive, white goods, and other growing sectors.

    Steel Coating Process:

    Inception

    The basis of most coated steel is cold-rolled steel.

    The sheet is covered with a metallic and/or non-metallic coating to prevent rust and corrosion that humidity and contamination can cause on the steel.

    Metallic coatings can consist of a zinc layer (Zintro) or alloys of zinc and other materials such as aluminum (Zintro Alum).

    Galvanization

    Galvanization can be done by immersion in molten metal or by electrochemical processes.

    The process starts with the placement of cold-rolled steel sheets.

    The edge of each roll is trimmed to remove imperfections.

    Then, it goes through alkaline or direct flame cleaning process to eliminate residues such as oil or particles.

    The sheet is then transported to a continuous annealing furnace to recover structural properties and ductility.

    It is then immersed in a molten metal crucible in which coating is adhered to; excess liquid metal is swept off with air or gas.

    Finally, the sheet is given a surface finish, treated with a chemical solution to protect the coating, a thin layer of oil oxide is applied, and then it is rolled.

    Electrogalvanization

    Electrogalvanization consists of immersing the material in an electrolytic solution of zinc chloride and passing an electric current through it.

    The current passage causes the zinc to adhere to the surface of the steel sheet and coat it.

    Painting

    Non-metallic coatings such as paint form a film that protects and embellishes the alloy when it dries (Pintro).

    Cut and Finish

    The production process ends with the cut or form into rolls, sheets, and strips of rectangular, square, circular, and triangular designs, among others.

    In addition, surface finishes and other treatments can be applied for specific uses.

    ALL ABOUT CONNECTIONS: HOW DIFFERENT TYPES OF STEEL BEAMS WORK
    When it comes to construction projects heavily involved in steel structures, it’s important to understand the available steel beams that work best for your specific needs. Different structural components are required for their distinct properties, so choosing the right structural steel beam is critical since they are designed for precise applications.

    If you’re wondering what type of steel beams you need, we’re here to give a lowdown on the different support beams you will encounter so you can arm yourself with enough information to make better decisions for your upcoming project. Here are the several types of structural steel beams:

    C-BEAMS

    Also known as channel beams, these are designed with top and bottom flanges to support a C-shaped construction, giving your structure better load-bearing capabilities and a stronger anchor.

    It’s an odd shape primarily used in bridges, but their unique web holes make them a perfect alternative for wide flange beams since you can achieve the same result with fewer pieces. Other ways to use a c-beam include brackets, cladding, covers, grating support, stiffeners, reinforcements, and even decorative purposes.

    I-BEAMS

    Widely regarded as a universal beam, the composition of its flanges create an “I” shape as it consists of two horizontal planes that connect at the web to provide vertical support.

    H-BEAMS

    One of the strongest steel beams on the list, H-beams, is made up of horizontal elements, while the vertical beams act as the web. The flanges and web create a cross-section that mimics the shape of the letter “H” and are popular in construction or civil engineering projects.

    W-BEAMS

    W-Beams are similar to I-beams, though the difference is that they come with wider flanges and web, which means it’s better to carry heavier loads. Of course, the drawback is that it also weighs more than I-beams, so they are often better for residential or commercial construction.

    T-BEAMS

    T-Beams perform excellently in bending and other load-bearing structures, making them the right choice for heavy-duty construction projects such as bridges. T-beams don’t sag, plus it suits larger spans since it reduces deflection.

    THE BOTTOM LINE: CHOOSING THE RIGHT STEEL BEAMS THAT BEST SUITS YOUR CONSTRUCTION PROJECT

    Steel beams come in all shapes and sizes, but their varying properties play a significant role in the type of construction you’re planning. It’s important to choose the right one for your project since it will impact its durability, longevity, and structural integrity, all of which are critical factors for building applications.

    ARE YOU LOOKING FOR CASTELLATED BEAM SUPPLIERS IN THE USA?

    If you’re on the hunt for quality yet affordable castellated beam materials, look no further than C-BEAM. We’re a steel beam company that offers wide-ranging supplies for your structural needs, but we also offer services like marketing, project manufacturing, and project management to streamline your process from concept to final delivery.

    When to Use Specialty Steels
    Specialty steels – also referred to as alloy steel – contain additional alloyed materials that deliver special properties to the final product. Specialty steels are engineered to provide superior performance under specific conditions. For bearings such as roller bearings and ball bearings, specialty steels would be selected versus other bearing materials to deliver properties that can best withstand the operating conditions the bearings will be exposed to.

    Various stainless steel alloys are included among common specialty steels. Typically, standard bearings are fabricated using chrome steel, which can be heat-treated and ground to deliver durability and high load capacity, allowing the bearings to perform well in broad applications.

    Depending on the operating conditions of the ball bearing or roller bearing, other specialty stainless steels may offer better performance. For specific applications, alloy steels can deliver a range of beneficial properties.

    Specialty steels offer a variety of enhanced characteristics, making them a preferred choice for ball bearings and roller bearings depending on the application. The benefits of specialty steels include:

    • High corrosion resistance
    • Targeted resistance to high and/or low temperatures
    • Easily fabricated
    • Dimensional stability and strength
    • Non-magnetic
    • Sterile and hygienic
    • Well suited for special applications
    • Lighter weight
    • Grease-free use

    Applications of Specialty Steels

    In the fabrication of bearings such as ball bearings or roller bearings, the enhanced properties offered by specialty steels make them well-suited for sensitive applications, such as:

    • Food and Beverage
    Specialty steels – such as AISI 4440C stainless steel – are used in bearings for food processing equipment because they can be easily cleaned and offer high corrosion resistance while maintaining durability at high and low temperatures. TC2 grease-free bearings may also be used if a lubricant-free product is more suitable for the application.
    • Chemical Industry
    AISI 304 stainless steel is selected for bearings used in chemical processing due to its ability to resist acids, such as chlorine gas, dry chlorine, ammonium sulfate, caustic soda, and others. This specialty steel can be used in acidic or alkaline environments.
    • Severe Environments
    Due to the high corrosion resistance, superior stability, high strength, and resistance at high and low temperatures, specialty steels are well suited for bearings used in many types of severe environments. Where standard bearings may fail, the properties of specialty steels offer high performance.

    Things You May Not Know about Galvanized Steel
    There are so many interesting facts surrounding steel. Did you know steel is the worlds’ most recycled material? Over two out of every three tons of steel is made from recycled materials, and up to 95 percent of some kinds of steel (the steel used in cars, for example) is used again.

    There are also fascinating facts about galvanized steel, steel that is dipped in molten zinc so it does not rust. Here are five things you probably didn’t know about galvanized steel.

    Galvanized steel was named after an eighteenth-century Italian scientist, Luigi Galvani.

    Luigi Galvani (1737-1798) was not just a premier physicist of his time but also a physician, philosopher, and biologist. He discovered that animal tissues — the classic example is applying electrical current to the muscles in a frog’s legs — respond to tiny electrical currents. Galvani’s discovery was so significant that all kinds of electrical currents came to be known as “galvanic.” When the discovery by Sir Humphry Davy 50 years later led to the understanding that zinc in contact with iron could protect iron from rusting through an electrochemical process, the procedure of coating iron with zinc became known as “galvanizing.”

    Galvanized steel is an inexpensive structural component and building material, and it costs relatively little to maintain.

    Galvanized steel costs a few cents per pound more than untreated structural steel. Its alternative, stainless steel, costs four to five times as much as galvanized steel. Any welder who works with regular steel can also work with galvanized steel, although welders need protection from zinc fumes. Specialized training is needed to do construction or manufacturing with stainless steel, and the cost of labor for stainless steel is about 50 percent higher.

    Buildings and structures made with galvanized steel may not need maintenance for 50 years or longer. This is not the case with either structural steel or stainless steel.

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