Today’s theme of Hooksoon Classroom
When procuring stainless steel materials, suppliers typically indicate the thickness tolerance provided by the steel mill on the product. It’s important to bear in mind that even within the same roll of steel, slight variations in measurements may occur at different points. This phenomenon is referred to as thickness tolerance.
- Reason:Throughout the rolling procedure conducted by the steel mill machinery, the steel coil can undergo deformation due to the heat generated by the rolling. This deformation leads to variations in the thickness of the rolled stainless steel coil. In general, the central thickness tends to be greater than that of the plate edges. This phenomenon is influenced by the characteristics of the process machinery and equipment.
- Tolerance:The majority of mentioned thickness tolerances pertain to negative tolerances (lower limits). However, positive tolerances (upper limits) are also applicable, albeit less frequently. For instance, aiming for a thickness of 2.0mm may result in an actual measurement of 1.97mm, which establishes the range of thickness tolerance as 1.97mm to 2.0mm.
- Standard:The specifications for thickness tolerance may exhibit slight variations based on different national standards. For instance, Taiwan predominantly adheres to CNS (National Standards of the Republic of China), the United States follows ASTM (American Society for Testing and Materials), and Japan adheres to JIS (Japanese Industrial Standards).
If customers have specific thickness requirements, it’s crucial for them to ensure that the center thickness does not surpass the tolerance range stipulated for the purchased steel coils. Moreover, there’s typically a variance in thickness from the beginning to the end of the coil. It’s advisable to unroll approximately one meter of the coil and re-measure the thickness.
