Steel plate and sheet: hot-rolled, chequer and structural
Steel plate and sheet are the flat carbon steel products behind fabricated parts, base plates, gussets, tanks, floors and machine frames, supplied hot-rolled, as chequer plate and to structural grades. ULAMEX supplies plate and sheet in S235JR, S275JR and S355J2, to EN 10025-2, EN 10029 and EN 10051, with a 3.1 certificate on request. This guide covers the difference between plate and sheet, chequer plate, grades, standards, surface and protection.
What steel plate and sheet are
Plate and sheet are flat-rolled carbon steel, and the split between them is thickness. Plate is the thicker product, from about 3 mm upward, used where strength and stiffness matter, for base plates, gussets, tanks, structural connections and heavy fabrication. Sheet is the thinner product, below about 3 mm, used for panels, guards, enclosures and light fabrication where the part is formed and does not carry heavy load. Both are supplied black, with a hot-rolled mill-scale surface, ready to be formed, welded and then protected.
Plate and sheet compared
| Product | Thickness | Typical use |
|---|---|---|
| Plate | About 3 mm and above | Base plates, gussets, tanks, structural and heavy fabrication |
| Hot-rolled sheet | Below about 3 mm | Panels, guards, enclosures, light fabrication |
| Chequer / tear plate | Patterned | Anti-slip floors, walkways, steps and vehicle decks |
| Wide flat | Rolled flat product | Straps, ties, flat structural members |
Plate is the load-carrying flat product, sheet the lighter formed product, and chequer plate the anti-slip floor product. The right one follows the thickness and the job.
Chequer and tear plate
Chequer plate, also called tear plate or floor plate, is steel plate rolled with a raised pattern on one face, a teardrop or diamond, that gives grip underfoot. It is used for walkways, platforms, steps, ramps, mezzanine floors and vehicle decks, anywhere a walking or loading surface must resist slipping. The pattern adds grip without adding much weight, and the flat underside sits cleanly on a frame. For a rust-free version of the same anti-slip floor, see our guide to aluminium tread plate.
Grades for plate and sheet
Plate and sheet are supplied in the non-alloy structural grades of EN 10025-2, matched to the load and the service temperature.
| Grade | Yield (min) | Character |
|---|---|---|
| S235JR | 235 MPa | General plate and sheet, impact tested at +20 C |
| S275JR | 275 MPa | Higher strength for more loaded parts |
| S355J2 | 355 MPa | High strength, impact tested at -20 C for demanding structures |
S235JR is the everyday mild steel plate, S275JR the higher-strength choice, and S355J2 the high-strength grade that stays tough in the cold. For the full grade detail see our guide to structural steel S235, S275 and S355.
Standards and tolerances
Plate and sheet are supplied to a material grade and a dimensional tolerance standard that depends on the product.
| Standard | Scope |
|---|---|
| EN 10025-2 | Grades and delivery conditions for non-alloy structural steel |
| EN 10029 | Tolerances on dimensions and shape for hot-rolled plate 3 mm and above |
| EN 10051 | Tolerances for continuously hot-rolled sheet and strip |
EN 10029 sets thickness, flatness and out-of-square limits for plate, with a thickness tolerance class agreed on order, and EN 10051 covers thinner hot-rolled sheet. Chequer plate is a patterned product supplied to a mill standard rather than EN 10029. State the grade, thickness, size and any tolerance class with an enquiry, and add the 3.1 certificate requirement.
Surface and edge
Hot-rolled plate and sheet leave the mill black, with a dark blue-grey scale that is normal and does not affect strength. Plate is supplied with a mill edge as rolled, or with a dressed edge where a clean or profiled edge is needed. For parts that are painted or shown, the scale is removed by shot blasting or pickling first. The edge and surface are specified to suit the next process, welding, machining or coating.
Forming and fabricating plate
Plate and sheet are formed and fabricated into finished parts. Plate is formed by pressing and rolling into curved and folded shapes, drilled or punched for bolted connections, and welded with standard mild-steel filler. Thicker plate is bevelled at the edges to make a weld preparation for full-penetration joints, and heavier fabrications are stress-relieved after welding where flatness matters. Structural fabrication of load-bearing plate work for the European market is carried out to EN 1090, and ULAMEX holds EN 1090-1 EXC2 with welding to ISO 3834-2, so plate is supplied ready for certified fabrication.
Plate and sheet weight
Flat steel is priced and shipped by weight, so the mass per square metre matters for cost, handling and structural design. Carbon steel has a density of about 7.85 g/cm3, which gives a flat product a mass of roughly 7.85 kg per square metre for every millimetre of thickness. A 10 mm plate is about 78.5 kg/m2, a 3 mm sheet about 23.6 kg/m2, and a 20 mm plate about 157 kg/m2. Chequer plate weighs slightly more than its base thickness because of the raised pattern. Give the thickness and the size with an enquiry and the desk returns the weight and the price together.
Applications
Steel plate and sheet are the flat building blocks of fabrication. Structural steelwork uses plate for base plates, gussets, cleats, stiffeners and connection plates. Tanks, silos, hoppers and pressure parts are rolled and welded from plate. Machine bases, frames, guards and wear parts use plate and sheet. Chequer plate makes walkways, platforms, steps and vehicle decks. Sheet forms panels, enclosures, ducting and light guards, and wide flat serves as straps, ties and flat members. Across all of these the flat product is formed and welded into the finished part.
Protecting plate and sheet
Bare carbon plate and sheet rust, so any part left exposed or damp is protected. Indoor dry parts can be primed; exposed parts are painted over a blast-cleaned and primed surface, or hot-dip galvanised for long-life outdoor protection. Where galvanising is chosen, see our guide to galvanised steel, and note that vent and drain holes suit the dipping of fabricated plate parts. Where the part must resist corrosion without a coating, stainless plate is the alternative.
Steel, stainless or aluminium flat product
Carbon plate and sheet suit most fabrication, but two alternatives cover jobs they cannot. Carbon steel is the strongest for the price and the easiest to form, drill and weld, so it is the default where corrosion is handled by a coating. Stainless plate resists corrosion in the metal itself, for food, marine, chemical and visible parts that must not rust. Aluminium plate and tread plate are about a third of the weight, do not rust, and suit floors, panels and transport parts where weight matters. ULAMEX supplies carbon, stainless and aluminium flat products, so a project sources the right material from one supplier.
Steel plate and sheet from ULAMEX
ULAMEX has supplied carbon steel since 1988, and flat products are a core part of the range.
| What you get | Detail |
|---|---|
| Products | Hot-rolled plate, hot-rolled sheet, chequer plate and wide flat |
| Grades | S235JR, S275JR and S355J2 to EN 10025-2 |
| Standards | EN 10029 plate tolerances, EN 10051 sheet tolerances |
| Fabrication | EN 1090-1 EXC2 with welding to ISO 3834-2; 3.1 certificate on request |
| Terms | No minimum order on stocked SKUs, dispatch 2 to 7 working days |
Need steel plate or sheet for a project? Send the grade, thickness, size or drawing, and ULAMEX will return a non-binding quotation. See our guides to structural sections and aluminium tread plate, and our supply capabilities, or contact the export desk at [email protected] or +48 504 424 761.
Frequently asked questions
What is the difference between steel plate and sheet?
Thickness. Plate is the thicker flat product, from about 3 mm upward, used for load-carrying and heavy fabrication. Sheet is thinner, below about 3 mm, used for panels, guards and light formed parts.
What is chequer plate?
Chequer plate, also called tear plate or floor plate, is steel plate rolled with a raised teardrop or diamond pattern on one face for grip. It is used for walkways, platforms, steps and vehicle decks. An aluminium tread plate version is available where the floor must not rust.
What grades are plate and sheet available in?
S235JR, S275JR and S355J2 to EN 10025-2. The number is the minimum yield in MPa and the suffix is the impact grade: JR at +20 C, J0 at 0 C and J2 at -20 C.
What standards apply to steel plate?
Grades to EN 10025-2, thickness and shape tolerances to EN 10029 for hot-rolled plate 3 mm and above, and EN 10051 for thinner continuously hot-rolled sheet. Chequer plate is supplied to a mill standard.
Which grade should I choose for a cold or heavily loaded structure?
S355J2, which is impact tested at -20 C, for structures that must stay tough in the cold or carry heavy load. S235JR and S275JR, tested at +20 C, suit general and moderately loaded work.
Does steel plate rust?
Yes, bare carbon plate rusts, so exposed or damp parts are protected by priming, painting over a blast-cleaned surface, or hot-dip galvanising. Where a part must resist corrosion without a coating, stainless plate is the alternative.
Do you supply a certificate for CE-marked steelwork?
Yes. A 3.1 inspection certificate is supplied on request, and ULAMEX holds EN 1090-1 EXC2 with welding to ISO 3834-2, so plate is ready for certified structural fabrication.
How much does steel plate weigh?
Carbon steel is about 7.85 g/cm3, so a flat product weighs roughly 7.85 kg per square metre for each millimetre of thickness. A 10 mm plate is about 78.5 kg/m2 and a 3 mm sheet about 23.6 kg/m2.