N-Grades: Identify Surface Roughness Better

N-Grades provide a simplified and standardized way of indicating materials’ surface roughness levels, benefiting manufacturers. By using N-Grades in technical drawings, manufacturers can ensure that the required roughness levels are met consistently and accurately.

Ignoring N-Grades in technical drawings can lead to confusion and errors in manufacturing, which can result in increased production costs and delays.

In technical drawings, Surface Roughness is an important parameter that can impact the functionality and aesthetics of a part. Surface roughness, which is the deviation of a surface from its ideal form, is commonly measured using parameters such as Ra, Rz, Rq, and Rt, among others. Numerous methods for measuring surface roughness make it challenging for manufacturers to understand and apply them.

ISO developed the N-Grades system to simplify identifying surface roughness in technical drawings. N-Grades refer to the new ISO Grade Scale Numbers that categorize surface roughness parameters into 12 grades ranging from N1 to N12. Most of the surface roughness parameters can be mapped to an N-Grade. N-Grades provide a streamlined and standardized way of indicating surface roughness levels. Werk24 converts surface roughness parameters to N-Grades based on the following table.

 

Advantages of N-Grades

  • N-Grades can prevent errors in interpretation and save time in measuring and specifying surface roughness.

  • N-Grades are independent of the unit measurement, making them easier to apply. This independence allows for consistent interpretation of the roughness level regardless of the measurement system used.

  • Mapping most of the surface roughness parameters to an N-Grade reduces complexity.

  • N-Grades allow you to standardize and simplify surface roughness annotation.