What is the standard thickness tolerance for steel sheet Q235

The standard thickness tolerance for steel sheet Q235 varies depending on the specific standard that is being used and the thickness range of the sheet.

In China, the national standard GB/T 709-2019 specifies the tolerances for hot-rolled steel plates and sheets in different thickness ranges. For Q235 steel sheets with a thickness of less than or equal to 20mm, the standard tolerance is ±0.5mm, while for sheets with a thickness greater than 20mm but less than or equal to 60mm, the tolerance is ±1.0mm. For sheets with a thickness between 60mm and 100mm, the tolerance is ±1.5mm.

In other countries, such as the United States, different standards may apply. For example, ASTM A568/A568M-19a, which covers carbon steel sheets, specifies the tolerances for thickness, width, and length. The tolerance for thickness depends on the thickness range and type of material, but for general-purpose carbon steel sheets like Q235, the tolerance is typically ±0.005 inches (0.13 mm) for sheets up to 0.229 inches (5.8 mm) thick and ±0.007 inches (0.18 mm) for thicker sheets.

It's important to refer to the specific standard being used to determine the appropriate tolerances for a particular steel sheet.