There are certain forms of steel that are often confused for one another, and a good example here is the use of steel sheet and steel plate. Not only are these two often mixed up, they’re often paired together for certain project needs — and this can make things even more complex for those who don’t know the basic differences between them.

At Wasatch Steel, we’re happy to offer a wide selection of both steel sheet and steel plate for our clients, plus assistance with choosing the right one — or both — for your project needs. What are the differences between these two product types, how are they processed, and which is right for your project needs? Here’s a primer.

Steel Sheet

Steel sheet metal is defined as any metal that’s thicker than foil, but thinner than plate (which we’ll get to in a moment). It’s determined by the gauge, or thickness, of the sheet. Steel foil is much thinner than steel sheet, typically between .010 to .5 milimeters (mm) in thickness. Anything thicker would be considered steel sheet, at least until it reaches 6mm — at which point it becomes steel plate.

Standard sheet metal can go through several different processing methods, including perforation, corrugation, slitting, blanking/shearing, and deep drawing. The sheet is then fabricated into a number of different shapes depending on your specific needs.

Steel Sheet Processing Methods

Steel sheet can be further segmented into the way it’s processed, for which there are two options:

• Hot-rolled steel sheet: This is steel that’s rolled at high temperatures (often around 2,000 degrees Fahrenheit), then left to cool. Due to the fact that it’s still hot when it’s finished processing, there may be residual stresses within the metal itself. Hot-rolled steel is ideal for forging, bending applications, and many forms of pipes and tubing. It’s often found in construction, vehicle frames, and other heavy-duty applications.
• Cold rolled steel sheet: This is formed when the steel is cooled in a room with very low humidity after it’s been hot-rolled. The cooling process is slower, making cold rolling more expensive and less common than hot rolling — but the outcome offers a thinner metal that requires even less processing time, meaning you gain a finished product that’s even stronger and more durable. Cold-rolled steel is ideal for stamping, coiling, and other types of metal fabrication. It’s also commonly found in structural metal parts and pieces of metal furniture.

Steel Plate

Steel plate metal is defined as any steel that’s thicker than sheet, but still considered flat-rolled. It’s determined by the thickness of the plate, which runs between .5mm to 10mm (it’s important to note that steel plate is not actually stamped or cut, but instead rolled). As with steel sheet, the difference in thickness between plate and sheet metal is significant.

Steel plate can be further processed into different shapes through blanking/shearing, rolling, and press breaking. It’s then often sent to the heat treat plant for processing into other shapes, or directly to fabricators.

Within steel plate are a few different categories: Low, medium and high carbon varieties. The more carbon content in a given piece of steel plate, the more sturdy and strong it’s going to be. Low carbon steel is the least durable (and cheapest), while medium and high carbon varieties offer more durability, but at a higher cost. High carbon steel plates are often used for bridges, I-beams and other applications where you’ll need increased strength.

Steel plate, in general, is often used for structural applications. It’s commonly found in bridges, for instance, as well as the chassis of large vehicles. This is because it’s very durable, can be rolled into different shapes, and provide more strength than steel sheet metal.

Common Uses of Steel Plate

Now that you know some basics on steel sheet and plate (plus foil options that are even thinner than steel sheet), how do you go about choosing which is ideal for your project? Here are some common areas where plate would be used:

• Fasteners: The use of steel plate to connect two items together can be a smart choice. For example, if you’re building a deck and need to fasten the planks together, steel plate will provide extra strength for your materials.
• Framing Steel Plate Frame: One of the most popular applications for steel plate is in framing — and here, the material must be strong while also lightweight. Hot-rolled steel might not be an ideal option because it’s thicker and heavier than cold-rolled steel plate, making it less efficient to transport for construction projects.
• Cold Rolled Steel Frame: This is preferred when you happen to have access to a nearby steel mill that can provide custom-cut pieces of steel plate. While cold-rolled steel is more expensive than hot-rolled, if you can find a mill that’s willing to cut your custom pieces, it might be the most cost-effective solution for certain projects.
• Tack Welding Steel Plate Frame: For smaller steel projects, tack welding plates together instead of using bolts or screws could be the way to go. While you’ll have less support with tack welding, it’s also much faster and requires fewer tools to pull off the job. This is ideal for small steel projects that are lightweight, yet still require strength.

Steel plate can vary in price depending on size, thickness and grade — but based on an average, it could cost about 10% more than steel sheet metal.

For more on steel plate and steel sheet, or to learn about any of our steel products or services, speak to the staff at Wasatch Steel today.