The classification of rolling and polishing surfaces shows the extent to which they can be achieved. Another effective representation is measuring surface roughness. The standard measurement method, called CLA (center line average), measures the lateral movement of the meter across the steel plate, recording the amplitude of the peak and valley changes. The smaller the number of CLA, the smoother the surface.
The final results of different grades can be seen from the surface processing and CLA numbering in the following table.