Average roughness value Ra (DIN 4768)
This is defined as the arithmetical mean of the absolute sums of the roughness profile R within the entire measured length lm.
Average roughness depth Rz (DIN 4768)
This is defined as the average value resulting from the single roughness depths of five successive single measured lengths le.
Single surface roughness depth Z1 ... Z5
This is the vertical distance between the highest and the lowest point of the roughness profile R within a single measured length le.
Maximum surface roughness depth Rt (DIN 4768/1)
This is the distance between the elevation and depression of the line within the measured length (reference distance) of a profile filtered according to DIN 4768 Bl.1.
in accordance with ISO 1302
in accordance with ISO 3141
|Arithmetical mean deviation||Ra [μm]||0.025||0.05||0.1||0.2||0.4||0.8||1.6||3.2||6.3||12.5||25||50|
|Surface roughness||Rz [μm]||0.25||0.63||1||1.6||2.5||4-6.3||10||16-25||40||63||100||160|
|Longitudinal turning Face turning||⬜||⬜||⬜||⬛||⬛|
|Cylindrical longitudinal grinding
Cylindrical surface grinding
⬜ = Roughness (can be achieved through special methods)
= Roughness (can be achieved with normal workshop practice)
⬛ = Roughness (can be achieved through rough machining)