This article takes an in-depth look at metal grating.
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Metal grating is composed of metallic sheets intricately arranged in a grid or lattice pattern. This structure may be achieved through perforation or assembly. It finds extensive usage across various industries as stairs, platforms, scaffolding, and shields. Manufacturing methods for metal gratings involve processes such as expansion, perforation, shaping, and welding.
Originally, metal grating was developed to enhance air circulation in subterranean settings to avert heat buildup and preserve cleanliness. During World War II, it became recognized for its swift deployment in creating runways and emergency pathways, affectionately dubbed "magic carpets."
Considerations involved in crafting metal gratings include thickness, bar sizes, pattern openings, load-bearing capacity, and the environmental conditions of the installation site. Metal gratings are remarkably versatile, available in standard dimensions or custom-built to meet unique application requirements. Customized alternatives are frequently employed to address specific needs for different installations.
Various metals can be employed in creating metal gratings, with iron, carbon steel, aluminum, and stainless steel being the most prevalent. These gratings are typically utilized for non-slip applications that necessitate a secure working platform.
Metal gratings are available in numerous patterns, designs, and configurations, including combinations of steel gratings with steel plates. Production methods encompass welding, press-locking, or integration with metal plates, all crafted to endure rigorous and challenging environments.
Engineers, architects, and designers prioritize creating highly functional metal grating solutions customized to the load-bearing, safety, and environmental needs of a given structure. When specifying metal grating, professionals assess critical factors such as thickness, surface area, load capacity, span, bar dimensions, panel size, and the arrangement or pattern of grating openings. These openings—commonly found in oval, square, and diamond configurations—can significantly impact the grating’s performance in industrial, commercial, and architectural applications.
During the metal grating design process, additional considerations include the required levels of light transmission, ventilation, drainage, and acoustic control, as well as the visual aesthetics and anti-slip properties. Heavier-duty gratings are frequently constructed from welded steel grating or pressure-locked bar grating for maximum strength and longevity, making them ideal for high-traffic floor grating, catwalks, and platforms in demanding environments such as manufacturing plants and chemical processing facilities.
Expanded metal grating is defined by its unique manufacturing technique: precision slits are made in a metal sheet, which is subsequently stretched and expanded into a diamond-shaped mesh pattern. This process creates a grating panel with integrated rigidity and durability without the need for welds or joints. Expanded metal gratings are fabricated from a range of materials, including carbon steel, stainless steel, and aluminum, to cater to both indoor and outdoor usages and corrosive environments.
Standard expanded metal grating features a slip-resistant surface, making it suitable for walkways, ramps, and safety platforms. Flattened expanded metal grating, produced through a cold rolling process, provides a smoother, more uniform finish for areas where foot traffic, wheeled equipment, or visual aesthetics are a priority. Non-flattened, or raised, expanded metal grating offers enhanced traction, making it ideal for anti-slip flooring solutions in facilities where worker safety is paramount.
Bar metal grating, sometimes referred to as industrial bar grating, is perhaps the most widely recognized type of metal grating. It is comprised of parallel load-bearing bars connected by perpendicular cross bars, offered in a variety of joining methods such as welded, press-locked, riveted, and swaged connections. Welding is the predominant technique, ensuring maximum rigidity and stability for industrial floor grating and catwalk grating.
Material selection—including galvanized steel, stainless steel bar grating, and aluminum bar grating—depends on load, environmental exposure, and corrosion resistance requirements. Bar grating’s high strength-to-weight ratio, open grid design, and ease of maintenance make it a longstanding choice for applications such as trench covers, stair treads, mezzanine floors, fire escapes, street drains, drainage grates, loading docks, catwalks, and bridges. Custom bar spacing and serrated surfaces provide optimal balance between traction, light passage, and debris control.
Wire mesh metal grating—also known as wire cloth or wire fabric grating—is produced from intersecting wires aligned in rows and columns to create a highly versatile, grid-like structure. This form of grating is prized for its adaptability, ease of installation, long service life, and excellent strength-to-weight properties, meeting the demands of commercial, architectural, industrial, and agricultural industries.
Depending on the application, welded wire mesh grating fuses intersecting wires together at every junction for maximum structural integrity, while woven wire mesh grating interlaces the wires like textile fabric, producing a flexible yet strong mesh. Wire mesh grating is frequently selected for machine guarding, safety enclosures, fencing, filtration, ventilation panels, stair treads, and shelving due to its open area, visibility, and customizable mesh sizes. Materials such as stainless steel wire mesh offer superior corrosion resistance in harsh environments.
Perforated metal grating is engineered by punching, stamping, or laser cutting precise holes—circular, square, or custom-shaped—into robust metal sheets such as carbon steel, stainless steel, galvanized steel, copper, or aluminum. Modern fabrication methods like rotary pinning, die punching, and laser cutting achieve accurate, repeatable patterns for tailored mechanical performance.
With excellent strength, customizable open areas, and inherently slip-resistant surfaces, perforated metal grating is used for industrial flooring, architectural facades, HVAC screens, equipment enclosures, acoustic panels, security screening, sunshades, and filtration systems. Its flexibility and load-bearing capability also address applications needing noise reduction, light diffusion, ventilation, and debris control in modern building design and manufacturing environments.
Safety grating, often called grip strut grating or anti-slip metal grating, is engineered specifically to deliver a stable, highly skid-resistant walking surface. The defining feature is the diamond-shaped or serrated punching pattern, designed to maximize grip and reduce slip and fall hazards in industrial settings, construction work platforms, maintenance walkways, and stairways.
Standard designs incorporate large open areas for effective drainage of liquids and debris, as well as optimal airflow for ventilation in both indoor and outdoor environments. The serrated edges and cold-stamped protrusions provide traction even in oil, water, or ice-prone settings, ensuring compliance with OSHA and workplace safety standards. Safety grating is commonly produced in galvanized steel or stainless steel for optimal durability and corrosion resistance.
Compound metal grating merges two or more types of metal grating—often combining bar grating and checkered plate—to create an even more robust, stable, and versatile flooring solution. Typically, a checkered (tread) plate is securely bonded to the top of welded steel bar grating; plate thickness ranges from 0.12 inch to 0.24 inch (3 mm to 6 mm). This design increases surface traction and load capacity, while also helping to distribute wheel and pedestrian loads over a wider area.
A variety of options exist, including integration with wire mesh layers, multiple bar grating panels, or perforated plates, to meet unique project requirements. Heavy gauge—and sometimes pre-galvanized—steel is preferred to prevent structural deformation during galvanizing or zinc coating processes, ensuring years of dependable, maintenance-free service, particularly in walkways, industrial platforms, and bridge decks subject to frequent heavy loads.
Press locked metal grating (or press-locked bar grating) stands out for its precise joining method: load and cross bars are notched and permanently pressed together at high pressure, forming a smooth, visually appealing, and seamless surface. This tight and stable configuration makes press-locked grating a leading choice for architectural grilles, decorative screens, fencing panels, and high-visibility projects, where both strength and aesthetics are important.
Available in carbon steel, aluminum, and galvanized steel options, press-locked bar grating is offered with a range of bar spacings, thicknesses, and customizable dimensions to suit everything from pedestrian catwalks and platforms to infill panels, exterior cladding, and stair rails. The uniform appearance and ease of fabrication make this style especially attractive for building facades and urban infrastructure, while maintaining structural integrity and long-lasting performance.
Choosing the right metal grating depends on critical factors such as material type, load requirements, environment, anti-slip needs, open area, and budget. Whether you need industrial bar grating for structural flooring, expanded metal grating for ventilation, wire mesh for infill panels, or custom-fabricated press-locked grating for architectural projects, partnering with reputable metal grating manufacturers ensures compliance with relevant standards (such as ANSI and OSHA), long-term performance, and tailored solutions. Explore leading metal grating suppliers to compare materials, coatings, load tables, and project support as you evaluate and purchase the most effective solution for your industrial, commercial, or architectural needs.
The term grating refers to any covering, frame, or open grid structure engineered to cover openings, provide structural support, serve as a platform, or offer protection in both industrial and commercial environments. Modern metal grating systems come in a wide variety of configurations and are made from several materials, including robust plastics and high-performance metals such as carbon steel, stainless steel, and aluminum alloys. When selecting a metal grating material, essential considerations include the application requirements, load-bearing capacity, environmental conditions, anticipated pedestrian or vehicular traffic, and whether the grating should also enhance the architectural or aesthetic appeal of the structure.
Metal gratings are integral to numerous applications where safety, drainage, ventilation, and structural performance are critical. Common uses span airports, manufacturing facilities, chemical processing plants, power stations, and other industrial environments thanks to their exceptional durability, slip resistance, and robust construction. Choosing the optimal grating ensures worker safety, operational efficiency, and long service life, which can help reduce maintenance costs and minimize downtime.
Aluminum metal gratings are recognized for their impressive malleability, high corrosion resistance, and ductility, as well as their excellent thermal conductivity and electrical conductivity. Lightweight and easy to fabricate, aluminum grating panels are non-toxic, non-magnetic, and naturally resistant to bacterial growth, making them ideal for food processing plants and environments where hygiene is paramount. Remarkably, aluminum gratings retain their toughness and integrity even in extreme cold, resisting brittleness and deformation. Alongside their strength, their clean, modern appearance and low maintenance requirements contribute to their popularity in industrial catwalks, walkways, decorative grating installations, and architectural projects where visual appeal is desired.
Light-duty steel metal grating is engineered for applications such as pedestrian walkways, maintenance platforms, machinery floors, and light rolling traffic scenarios, including carts and hand trucks. Typically fabricated as bar grating—using techniques such as swaging, riveting, dovetailing, or welding—these panels are constructed from carbon steel featuring load-bearing bars and perpendicular cross bars to create a sturdy, open grid. The open-grid design allows for excellent drainage, ventilation, and slip resistance, enhancing safety in workplace settings. Its cost-effectiveness, durability, and minimal maintenance demands make steel grating a preferred option for industrial safety barriers, catwalks, and highway drainage platforms. Light-duty grating is also valued for its ability to meet OSHA safety standards and provide dependable support in both indoor and outdoor applications.
Several grades of stainless steel are utilized in the manufacture of stainless steel metal grating, including grades 304, 304L, 316, and 316L. Noted for their corrosion resistance, high tensile strength, and longevity, stainless steel gratings are engineered to withstand exposure to caustic chemicals, high-humidity environments, and significant temperature fluctuations. Standard manufacturing processes, including swaging and welding, enable a diverse range of bar grating panel sizes and configurations, from narrow trench covers to wide platform panels.
Stainless steel grating is a top choice for platforms, stair treads, and floorings in water treatment facilities, food processing plants, chemical manufacturing, petrochemical refineries, and oil and gas production environments. Its enhanced slip resistance and ability to endure both indoor and harsh outdoor settings make it suitable for high-traffic areas demanding stringent hygiene, chemical resistance, and non-corrosive properties. Custom fabrication options are available for unique industrial applications, supporting architectural flexibility and long-term reliability.
Galvanized steel grating is composed of carbon steel grated panels that undergo hot-dip galvanization—a process where the grating is coated with a protective layer of zinc to prevent rust, enhance resistance to corrosion, and extend service life. This galvanized finish makes the grating highly durable for both indoor and outdoor installations, especially where heavy moisture, chemicals, or abrasive substances are common. Over time, the zinc coating gradually wears, which acts as a sacrificial barrier to ensure the underlying steel remains protected.
Most galvanized steel gratings meet or exceed B load class standards—capable of withstanding loads up to 28,000 lbs (125 kN) as defined by Deutsches Institut für Normung (DIN), making them suitable for use in mining operations, transportation hubs, drainage covers, loading bays, and municipal infrastructure projects. Their slip-resistant surfaces and ease of installation further contribute to their popularity in a wide range of industrial and commercial grating applications.
Heavy-duty carbon steel metal gratings are manufactured with deeper, thicker load bars that are joined at elevated temperatures to form exceptionally robust and rigid grid structures. This high-strength grating is designed to support substantial loads, making it essential for heavy industrial applications such as truck loading docks, airfields, mining platforms, and large equipment housings. Heavy-duty carbon steel grating is engineered to withstand aggressive impacts, heavy rolling traffic, and long-term wear, while still allowing for drainage and ventilation in the work environment.
Beyond durability and load capacity, these gratings are valued for their customizable sizing, anti-slip surfaces, and versatility in challenging conditions. Their reliable performance and ability to be fabricated to exacting specifications make them the preferred choice for projects requiring top-tier safety, longevity, and structural support in rugged industrial settings.
Choosing the Right Metal Grating for Your Project
When specifying metal grating products, consider the project's specific needs, including anticipated traffic type (pedestrian, vehicular, machinery), environmental conditions (corrosive, high-moisture, extreme temperature), budget constraints, and long-term maintenance requirements. Consult with leading metal grating manufacturers and industry experts to ensure compliance with regulatory codes and safety standards. Carefully evaluating these factors will help maximize safety, efficiency, and longevity in your selected grating solution. For detailed technical guidance, project estimation, or to request a quote, reach out to qualified metal grating suppliers familiar with both standard and custom grating systems.
The production of grating varies based on the materials and manufacturing techniques used. Common methods include welding, dovetailing, stretching, and swaging, with welding being the most frequently employed. The choice of method depends on factors such as material thickness, weight, and the intended use of the grating.
Regardless of the chosen manufacturing process, selecting the appropriate metal is the initial step. This decision is guided by the environmental conditions and the required strength and durability of the grating.
Expanded metal grating starts with metal sheets that have diamond-shaped cuts. This process involves cutting diamond-shaped slits into the metal while stretching the sheets in a single operation.
During the piercing and stretching process, expanded metal grating develops a raised surface with consistent bonds and strands angled relative to the plane of the metal sheet. This results in a grate with notable strength and rigidity. For applications needing a smooth surface, the metal sheets can be flattened between rollers.
Non-flattened expanded metal grating, also known as raised metal grating, features a three-dimensional appearance due to its angled or bumpy texture. This design enhances its strength and rigidity. It is used in various applications, including platforms, walkways, protective panels, speaker grills, and fluid or air filters. The key advantage of non-flattened grating is its contribution to structural strength and stability.
Swaging is a cold metalworking technique that deforms metal to fit precisely into another metal component through applied force. In the production of metal gratings, the process starts with load-bearing metal bars spaced evenly for structural integrity and design. Tubular bars are then placed across these load-bearing bars at regular intervals and are joined using electrode welding. The depth and spacing of the bars can be adjusted based on the intended application of the grating.
Dovetailing is a traditional manufacturing technique used for centuries to join different materials. In metal grating, this process starts with precision slotting of the load-bearing and cross bars. The slots are meticulously cut to ensure a snug fit for the cross bars within the load-bearing bars.
Once the bars are correctly aligned, a hydraulic press is used to apply pressure, forcing the metal pieces into a permanent, secure lock. This creates a tightly connected, flat surface with enhanced rigidity. The dovetail design provides lateral stability and effective distribution of axial loads. Metal gratings with quarter-inch clean openings manufactured using dovetailing are often preferred in public areas where drainage and high-heeled traffic are considerations.
Welded metal grating is created through an electro-forging process, where rectangular load-bearing bars are welded to cross bars. This welding method results in a strong, durable connection between the bars. The thickness of the load-bearing bars in welded metal grating ranges from 0.125 inches to 0.5 inches (0.3175 cm to 1.27 cm).
Welded metal grating is one of the most widely used types, suitable for various applications. It can be left in its raw metal state or finished with options such as paint, hot-dipped galvanizing, enamel, epoxy coatings, or powder coatings for added protection and aesthetics.
Riveted metal grating is made using materials such as carbon steel, 6000 series aluminum, and 300 series stainless steel. The production involves riveting crimped flat bars in a reticulated pattern onto load-bearing bars. This method produces gratings with enhanced resistance to impact, fatigue, and heavy loads. The reticulated cross bars offer excellent strength and durability, making them suitable for applications requiring high stress and pressure endurance.
Metal gratings typically come with open ends but can be enhanced with banding—flat metal bars welded to the edges of grating panels. Banding improves the stiffness of the gratings and provides a finished, architectural look. It is essential for removable metal gratings to ensure safety during installation and removal.
For areas with motor traffic, banding is crucial to minimize impact loads on adjacent load-bearing bars and prevent deformation. Trench banding is an additional option where the band bar is positioned above the load-bearing bars in drainage applications, allowing for effective drainage while maintaining structural integrity.
Standard banding offers a uniform finish and aligns with the depth of the grating bars, welded centrally. Load banding features welds at each load-bearing bar to evenly distribute the load across the grating panel and provide a consistent end finish.
Various types of mechanical fasteners are used to securely connect metal gratings through friction. These fasteners come in different sizes and styles to accommodate the specific requirements of different metal grating forms.
Weld Lugs – Weld lugs are welded between the load-bearing bars such that the metal grating can be bolted to the supporting structure.
Industrial products, including metal gratings, are produced according to established standards. The two most widely recognized standards are those from the American National Standards Institute (ANSI) and the Deutsches Institut fĂĽr Normung (DIN), also known as the German Institute for Standardization.
DIN uses a classification system from A to F, while ANSI provides classifications based on the specific applications and performance requirements of the metal grating.
ANSI standards categorize metal gratings into five groups based on their load-bearing capacity:
Light Duty – Suitable for loads under 2,000 lbs (900 kg), these gratings are designed for pedestrian traffic only.
Medium Duty – Capable of supporting loads ranging from 2,000 lbs to 5,000 lbs (900 kg to 2,250 kg), this grating is appropriate for light pneumatic traffic, sidewalks, and residential parking areas.
Heavy Duty – These gratings support loads between 5,000 lbs and 7,500 lbs (2,250 kg to 3,375 kg) and are used for commercial traffic and tractor trailers.
Extra Heavy Duty – Designed for use on roads, highways, and bridges, this grating has an H-20 load rating, supporting up to 10,000 lbs (4,500 kg).
Special Duty – Built to withstand airport traffic and loads of 10,000 lbs (4,500 kg) or more, these gratings are engineered for high-demand applications.
Load Class A – Designed for pedestrian traffic, Load Class A can support up to 3,370 lbs or 15 kilonewtons (kN).
Load Class B – Suitable for parking lots, sidewalks, and light vehicular traffic, this class supports up to 28,000 lbs or 125 kN.
Load Class C – For commercial use, Load Class C handles loads of up to 56,000 lbs or 250 kN.
Load Class D – This class is intended for very heavy-duty applications with an H-20 rating, supporting up to 90,000 lbs or 400 kN. It is suitable for use with forklifts, roads, bridges, and highways.
Load Class E – Capable of withstanding diverse manufacturing and transportation conditions, including high-impact steel struts and metal wheels, Load Class E supports up to 134,000 lbs or 600 kN.
Load Class F – Designed for airport traffic, Load Class F has a load-bearing capacity exceeding 200,000 lbs or 900 kN.
Metal grating is frequently used as a safety feature to offer a stable, secure, and firm work surface with excellent traction. Additionally, it can be utilized as a barrier to help prevent accidents in hazardous or unsafe conditions.
The choice of metal grating depends on the material used. Aluminum and stainless steel are ideal for corrosive and moist environments, while carbon steel provides the strength and durability needed for heavy-duty applications.
Metal gratings enhance the aesthetic appeal of various structures, including flooring, walkways, platforms, and mezzanines. Their safe, robust, and durable characteristics make them an excellent choice for adding both functionality and visual interest to any construction. The cohesive quality of metal gratings contributes to a sense of continuity while also serving as a protective barrier.
Metal gratings are utilized in water filtration systems due to their corrosion resistance and remarkable strength. Their efficiency is highlighted by their ability to process large volumes with minimal material usage and a long service life. Pressed metal gratings are particularly effective in capturing large debris, such as plastic bags and boxes, from water before further processing.
Metal grating is commonly used for flooring and can be crafted from various alloys to meet specific application requirements. Aluminum floor grates are ideal for marine and wastewater environments due to aluminum's lightweight nature, which makes them easy to handle and position in tight spaces.
Steel metal floor grating is typically employed in heavy-duty settings where strength and a rugged surface are essential. Production facilities rely on steel grating for its superior performance and safety in demanding environments.
Metal grating fencing combines an attractive appearance with the strength and rigidity needed for high-security applications. The secure connections between grating panels make it ideal for areas requiring protection from intruders. Metal grating fencing can be customized and fabricated to fit any site, ensuring a precise match to the location's dimensions.
Wire mesh is fabricated by the intertwining, weaving, or welding of wires of various thicknesses to create proportionally equal parallel rows and intersecting columns. Also known as wire fabric, wire cloth, or...
Expanded metal is a sheet metal mesh. It is made by stretching a slitted sheet of malleable metal. The orientation of the slits is perpendicular to the direction of the stretch. The result of such stretching is an array of holes on the slits - to give a mesh form...
Hardware cloth is a woven mesh made by interlacing various sizes of wire to form a metal fabric that can be used for animal cages, fence material, strainers, and filtering screens. The differences between the various types of hardware cloth...
The phrase "wire mesh" describes two- or three-dimensional structures constructed of two or more metallic wires connected by various techniques. In a wide range of settings, wire mesh products are...
Perforated aluminum consists of an aluminum sheet which has been manually or mechanically pierced or punched using CNC (computerized numerical control) technology in order to produce shapes and patterns of various sizes...
Perforated metals are sheets of metal that have had decorative shapes, and holes punched or stamped into their surface for practical or aesthetic purposes. The perforation of metal sheets takes several forms and includes a variety of geometrical patterns and designs...
A perforated metal is a piece of sheet metal that has been stamped, fabricated, or punched to create a pattern of holes, slots, and various aesthetic shapes. A wide range of metals are used in the perforating metal process, which include steel, aluminum, stainless steel, copper, and titanium...
Perforated stainless steel is cut, punched, or stamped to produce a precise pattern of holes or apertures. It is used for functional reasons, such as filtration or ventilation, and aesthetic ones, such as architectural accents...
Perforated metals are sheets of metal that have had decorative shapes, and holes punched or stamped into their surface for practical or aesthetic purposes. The perforation of metal sheets takes several forms and includes a variety of geometrical patterns and designs...
Welded wire mesh is a series of wires that are welded where the individual wires cross. The openings of the mesh varies depending on the type of wire used and the function of the mesh. Regardless of size and wire, welded wire mesh is permanent and...
Wire cloth is a woven (or nonwoven) sheet or web material with a series of openings across the surface. Wire cloth is also known as: Metal Fabric or Metal Cloth; Wire Mesh, Metal Mesh, or Alloy Mesh...