Amount of embedding
| Symbol | fZ |
|---|---|
| Unit | - |
| Attribute-ID | vdi_2230_amount_of_embedding_combo |
| Numeric ID | 19217 |
| Value Type | PMString |
For the amount of embedding fZ from the plastic deformation of the contact surfaces the following selection options are available:
- User input, i.e. a direct numerical input of the amount of embedding.
- Acc. to VDI 2230, i.e. the calculation according to the guideline (R4) based on the mean roughness depth Rz according to ISO 4287, the number of inner interfaces and the load type.
Example: Rz = 20 µm, tension/compression and shear → fZ = 3 + 2 · 4.5 + 2 · 2.5 = 17 µm
| 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 Part1, 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".