Here’s a quick fact: Flat isn’t always just flat. More specifically, when it comes to stainless steel bars, there are two different types of flat: true flat and edge-conditioned flat (also known to some as gauered flat).
True Flat Stainless Steel BarsTrue flat stainless steel bars are those that have been produced on a rolling mill. In instances when the material needs to be polished in order to create a more consistent finish across all four sides (think architectural and aerospace applications), true flat bars often win out.
Other typical end uses for true flat stainless steel bars include food machinery, conveyor equipment, packaging equipment, bottling equipment, separators, and chemical processing, among others.
When compared to edge-conditioned flat stainless steel bars, true flat has a wider variety of grades:• 304/304L stainless steel flat bar
• 316/316L stainless steel flat bar
• 303 stainless steel flat bar
• 17-4 stainless steel flat bar
Why use true flat stainless steel bar:• Tighter tolerances – thickness & width
• Better squareness on edge
• Can be produced as hot roll annealed and pickled or cold drawn
Be aware:• Longer mill lead-times
• Cost of production can be higher than cut flats
• A limited number of US-based mills produce true flat bars
Edge-Conditioned Flat Stainless Steel Bars
Edge-conditioned flat stainless steel bars don’t start out as bars. They have been slit from coil or sheared or saw cut from plate, before the edge is conditioned. This means the edges may have a slightly different finish from the flat sides. In addition, edge-conditioned flat stainless steel bars may not be truly as flat as a true flat stainless steel bar.
Among the common uses for edge-conditioned stainless steel bars are stiffeners for tank manufacturing, ornamental applications, grab bars, bar rings, and structural members, among others.
Typical grades for edge-conditioned stainless steel flat bars are 304/304L stainless steel flat bar and 316/316L stainless steel flat bar.
Why use edge-conditioned stainless steel flat bar:
• The cost of product is typically less than true flat
• There is a larger market for cut flats
• Can be an outstanding value where tolerances will permit
• Widely available and can typically have short lead times
• Can be purchased already polished on two or four sides
• Tolerances are typically not as tight, as it is difficult to use precision equipment
• Edges are not as square – difficult to machine or finish easily
• Thickness limitations exist due to slitting, shearing and gauge-edge constraints