{"id":7661,"date":"2026-08-13T17:35:48","date_gmt":"2026-08-13T09:35:48","guid":{"rendered":"https:\/\/www.bomissteel.com\/a-detailed-understanding-of-steel-strip\/"},"modified":"2026-08-19T15:46:55","modified_gmt":"2026-08-19T07:46:55","slug":"a-detailed-understanding-of-steel-strip","status":"publish","type":"post","link":"https:\/\/www.bomissteel.com\/pt\/a-detailed-understanding-of-steel-strip\/","title":{"rendered":"A Detailed Understanding of Steel Strip"},"content":{"rendered":"

Conclus\u00e3o sobre IA:<\/strong> The width is what distinguishes steel strip from steel sheet. A strip is any width of 24 inches (approx. 610 mm) or less. Anything wider than that is sheet metal. The strip is manufactured by hot rolling, pickling and cold rolling the steel strip. An intermediate annealing step can be carried out depending on the required mechanical properties. The choice of material is dependent on the environmental conditions. The most economical choice for general outdoor use is galvanizado<\/a> steel strip. Aluminum-zinc coating is more durable in the coastal areas with high humidity and high temperature. This coating is made of about 55% aluminium and 43% zinc. If a specific colour is desired, the steel substrate is split into two groups, galvanised and aluminum-zinc. The latter applies to coastal and industrial projects. The HS codes are HS code 721230 for galvanised strips, HS code 721250 for aluminum-zinc coated strips and HS code 721240 for colour coated strips. Typical thicknesses are from 0.13 to 2.5 mm. Prices depend on the material, thickness, coating thickness and embalagem<\/a>.<\/p>\n

Many buyers ask what is the difference between steel strip and steel sheet metal. Are galvanised steel and galvanised aluminium similar? What is the substrate for color-coated sheets? Do I need a galvanised steel or galvanised aluminium substrate? The fact that many people ask these questions shows that it may seem simple, but it often causes confusion when ordering. Just 2.5 cm difference in width can mean that the specifications are totally wrong. Rust and peeling developed in two to three years due to the wrong choice of steel substrate and installation of the material on a coastal project.<\/p>\n

\"Especifica\u00e7\u00e3o<\/p>\n

The steel strip unit price is not high, but the scope of application is very wide, it is used in three industries: construction, automobile manufacturing, manufacturing industry. There it’s the basis for roofs, wall panels, ducts, fences, solar mounts and lots more. Usually deliveries are in coils. The supplier should be consulted before ordering to clarify the number of metric tonnes per container, delivery to the port etc. Because of the large quantities involved, the costs of a wrong decision are also high: if the material is found to be unsuitable for the task after purchase, problems occur with returns and the project cannot be delayed any longer to complete. It is therefore much cheaper to clarify a few points before ordering than to fix them afterward.<\/p>\n

The article explains steel strip from the ground up. How does it go from hot-rolled coil to finished product? What is the difference between steel strip and steel sheet? Then we will explain the most common products, which include galvanised steel strip, aluminum-galvanized steel strip, color-coated galvanised sheet and color-coated aluminum-galvanized sheet. We’ll walk you through the technology, properties and applications. After reading this text you will be able to state precisely in your order the material, the width, the thickness and the coating and avoid unnecessary complications in coordinating the specifications with your supplier.<\/p>\n

Steel Strip: What Is It? Steel strip and steel sheet: What’s the difference?<\/h2>\n

Steel strip is also called cold-rolled steel strip. Its raw material is the hot-rolled coil. First, this is pickled to remove scale and impurities from the surface. Hence the term \u201ccold-rolled.\u201d The pickling line might seem unremarkable, but it\u2019s actually very important. The surface treatment must be done thoroughly before the subsequent cold rolling can be done evenly, and the coating can be applied only when it is really needed.<\/p>\n

Cold-rolling mills are of different types. This is the easiest and most direct way. A single stand mill rolls the material in one pass. The stand stays still in a reversing mill, and the coil moves back and forth, allowing for multiple passes. In a tandem mill, a number of stands are arranged in a row, and the coils are rolled in a continuous line, allowing for a higher throughput and heavier coil weights. In-line rolling mills are the standard for large scale operations. Small-scale, single-stand and reversing rolling mills are in common use.<\/p>\n

Depending on the particular recipe, annealing may be necessary. The material can be cold-rolled directly to a thickness close to that of the final product without intermediate rollings. Alternatively, the annealing may be at a specific intermediate thickness (to soften the grains so that further rolling is easier or to obtain the desired mechanical properties). The process depends on whether or not the material is to be specially softened.<\/p>\n

The next point is the easiest to remember. How do you tell strip steel from sheet steel? You check the width. Coils larger than 610 mm (24 inches) in width are called steel sheet. Strip steel is steel which is less than 610 mm wide. This distinction is so sharp that it applies to both international trade and domestic orders.<\/p>\n

Another misconception is also often held: Many narrow sheets are slit by the supplier into wide longitudinal cuts (slitting). Strip steel is material that has been cut and has a width of less than 610 mm. The word \u201ccut\u201d in a quote refers to the cutting of wide coils into narrow strips. Some narrow strip materials are supplied in coil form and cut separately to length before shipment. Best to specify when you order.<\/p>\n

Galvanised steel strips – the cheapest way to protect against corrosion – is that enough?<\/h2>\n

Galvanised Steel Strips (GI) are made by coating the surface of Steel Strips with zinc. In hot-dip galvanising, the steel strip is dipped into molten zinc to form a zinc coating. A thinner and more uniform coating is produced by electrogalvanizing, which involves the depositing of zinc ions using an electric current. Hot-dip galvanising is the normal process for mass-produced items. Electrogalvanizing is used mainly for precision parts where uniformity of coating is important.<\/p>\n

The zinc coating has only one function, that of a barrier. As long as the water vapour never touches the steel below, it can’t rust. This principle seems simple, but is especially effective outside – fences, gates, support structures, and other parts exposed to years of rain and sun will last for decades with proper care. Maintenance is simple; inspect the zinc coating for damage regularly and patch any bare areas to extend its service life.<\/p>\n

Another advantage of galvanised steel strip is the low cost. The unit price is cheaper than stainless steel and aluminum-coated steel. Its corrosion protection<\/a> is fully sufficient for normal operating conditions. Therefore, galvanised steel strip is widely used in large quantities in many industries, such as construction, automotive industry, electrical engineering and agriculture – cable tray, cable ducts, equipment enclosures – it can be found everywhere. Suppliers need to know the exact zinc coating weight when asking for specifications as they will quote on the weight. Do not forget this detail.<\/p>\n

So are there any downsides? Yup. Zinc coating is sensitive to salt and long-term high humidity. In environments such as coastal projects and pickling shops, the service life of galvanised steel is greatly reduced; aluminum-zinc coated steel should be considered. Galvanisation is the economical answer for inland projects and outdoor environments with moderate humidity. Don\u2019t spend money on performance you won\u2019t use. This is a fundamental procurement skill. First define the environmental requirements, then talk about the materials not vice versa.<\/p>\n

Aluminum-zinc coated steel strip: where did the money go?<\/h2>\n

Aluminum-zinc coated steel strip is called \u201cGalvalume\u201d in English and \u201cAluzinc\u201d in Chinese. It has ‘aluminium’ in the name, and it actually does contain aluminium. The coating is made up of roughly 55% aluminium, 43% zinc, and small amounts of silicon. The process is similar to hot-dip galvanising, the only difference is the makeup of the galvanising solution. The addition of aluminium to the zinc bath changes the performance characteristics.<\/p>\n

The addition of aluminium resulted in two major improvements. First, resistance to corrosion. Aluminium will form a dense oxide layer on its surface and this layer is more resistant to high humidity and salt spray than a pure zinc layer. This is especially helpful in coastal areas. Secondly, heat resistance: Metal roofs often reach 70-80 \u00b0C in the sun, and aluminum-zinc coatings are significantly more stable in this temperature range than zinc coatings. The aluminum-zinc coatings are more resistant to the early ageing for roofs with heat sources, such as factory buildings and machine rooms.<\/p>\n

It is also worth mentioning the division of roles between the two metals: aluminium oxidises and forms a protective film against corrosion, and zinc continues to act as a sacrificial layer. If the film is damaged, it is the zinc that corrodes first, not the steel. The total corrosion rate is a little less than that of a pure zinc coating. This ensures a longer service life, especially for applications with a service life of more than 10 years, such as roofs and wall panels.<\/p>\n

Another, rarely talked about, benefit is the looks. The aluminum-zinc coating surface is silver-grey and has a crystalline structure, so it looks better outdoors than pure zinc coatings. Doesn’t need any extra finishing for exposed architectural features and decorative elements and can be applied even directly on walls.<\/p>\n

The main areas of application are roofs and wall panels, but it is also widely used for HVAC ducts, construction of agricultural and storage buildings and solar panel frames. This is where the corrosion resistance of the aluminum-zinc coating comes into play, as solar panel mounts are exposed to the elements for extended periods of time. An important point: for projects near the coast, in high temperature areas or where the roof is expected to have a lifespan of several decades, or even 20 years, the investment in the aluminum-zinc coating pays for itself because of its long service life.<\/p>\n

How to Choose a Coloured Sheet: Zinc or Aluminum-Zinc Based?<\/h2>\n

A color-coated steel sheet is produced by coating a steel substrate, applying paint, and forming the coated steel sheet into shape. The substrate can have two types: galvanised and aluminium-zinc. The corresponding products are colour coated galvanised sheet (PPGI) and colour coated aluminium-zinc sheet (PPGL<\/a>). This coating has other advantages and provides a cleaner look.<\/p>\n

First on coated zinc sheets. The steel substrate is a galvanised steel with high quality exterior coating. The coating protects against corrosion and UV radiation, and forms a further protective layer over the zinc coating. The light colours reflect the sunlight, so the roof does not absorb as much heat. This means that it will be cooler in the summer and you will not have to spend as much money on the air conditioning. The paint finish is colourfast, non-peeling and maintenance free all year round. Thanks to a broad spectrum of colours and finishes it is suitable for any architectural style. It is the most common type of color-coated steel sheet metal and is appropriate for residential and commercial roofs, agricultural buildings, warehouses, and wall cladding.<\/p>\n

Colour Coated Galvanised Aluminium Sheet. This product replaces the base material with galvanised aluminium, providing corrosion resistance, high temperature resistance, and the colour coated appearance of galvanised aluminium in a single sheet. It specialises in coastal and industrial settings. Conventional color-coated sheet metal is often damaged by salt spray and industrial gas. PPGL also exhibits superior colour stability, retaining its brightness even after years of sun exposure. This increases the service life of the roof coating compared to PPGI<\/a> and ensures an attractive appearance. Common applications are industrial and commercial roofs, residential buildings, agricultural buildings, greenhouses and energy efficient buildings.<\/p>\n

How do you select the correct sheet metal? Consider the steel substrate and the painted surface separately. The steel substrate determines the minimum corrosion protection and service life. The coated surface determines the appearance, texture, colour and reflectivity. If the environmental conditions are good and you have a small budget, PPGI is enough. PPGL is recommended for coastal areas, industrial areas, and long term use. The price difference between PPGI and PPGL is not so big for a roof with a service life of more than ten years, and the more expensive one is the wrong choice. If you are unsure, give the supplier the location of the project and the expected service life and they can calculate the costs.<\/p>\n

Related Products<\/h2>\n

Looking to source steel strip or coated coil for your project? These BOMIS Steel<\/a> products pair directly with the material families discussed above:<\/p>\n