| Symbol | Rz |
|---|---|
| Unit | µm |
| Attribute-ID | vdi_2230_roughness_height_according_to_ISO_4287 |
| Numeric ID | 12176 |
| Value Type | PMTechValue |
The roughness height according to ISO 4287 Rz affects the amount of embedding fz (R4).
The following selections are available:
| Average roughness height Rz according to ISO 4287a) | Loading | Guide values for amounts of embedding in µm | ||
| in the thread | per head or nut bearing area | per inner interface | ||
| < 10 µm | tension/compression | 3 | 2.5 | 1.5 |
| shear | 3 | 3 | 2 | |
| 10 µm to < 40 µm | tension/compression | 3 | 3 | 2 |
| shear | 3 | 4.5 | 2.5 | |
| 40 µm to < 160 µm | tension/compression | 3 | 4 | 3 |
| shear | 3 | 6.5 | 3.5 | |
a) Mean value from the maximum surface roughness Rt of at least two sampling lengths; with five sampling lengths, Rz corresponds with a good approximation of the “old” Rz from DIN 4768
Table from: VDI 2230 Part 1, VDI Verlag Düsseldorf, 2015, p. 73, "Table A5. Guide values for amounts of embedding of bolts, nuts and compact clamped parts made of steel, without coatings."