| Symbol | d12.9 |
|---|---|
| Unit | mm |
| Attribute-ID | vdi_2230_pre_size_diameter_for_12p9 |
| Numeric ID | 19148 |
| Value Type | PMTechValue |
Using the bolt pre-dimensioning from VDI 2230 Table A7, possible nominal diameters for the bolt are recommended based on the load (axial force, shear force), the type of load (static/dynamic, centric/eccentric) and the tightening method (large/medium/no scatter) depending on the strength grade.
Proceed according to Table A7:
A - select next larger force, for combination of axial and transverse force applies: FAmax < FQmax/µTmin then calculation continues with FQmax, otherwise with FAmax
B1 - when designing according to FQmax go 4 steps further with the force
B2 - when designing according to FAmax go 2 steps further in force for dynamic and eccentric, 1 step for dynamic and centric or static and eccentric, or 0 steps for static and centric
C - go 2 steps further in the force in case of tightening with large scatter, 1 step in case of medium scatter and 0 steps if there is no scatter.
D - Recommended nominal diameters according to the strength grade
| Force in N |
Nominal diameter in mm |
||
| Strength grade | |||
| 12.9 | 10.9 | 8.8 | |
| 250 | - | - | - |
| 400 | - | - | - |
| 630 | - | - | - |
| 1000 | 3 | 3 | 3 |
| 1600 | 3 | 3 | 3 |
| 2500 | 3 | 3 | 4 |
| 4000 | 4 | 4 | 5 |
| 6300 | 4 | 5 | 6 |
| 10000 | 5 | 6 | 8 |
| 16000 | 6 | 8 | 10 |
| 25000 | 8 | 10 | 12 |
| 40000 | 10 | 12 | 14 |
| 63000 | 12 | 14 | 16 |
| 100000 | 16 | 18 | 20 |
| 160000 | 20 | 22 | 24 |
| 250000 | 24 | 27 | 30 |
| 400000 | 30 | 33 | 36 |
| 630000 | 36 | 39 | - |
Table from: VDI 2230 sheet 1, VDI Verlag Düsseldorf, 2015, p. 117, "Table A7. Estimating the diameter range of bolts"
Example:
A - FAmax = 8500N so the next higher force level is for FMmax = 10000N
B2 - dynamic and eccentric, thus 2 steps further to 25000N
C - Tighten with torque wrench 1 step further to 40000N
D - choice of strength grade of 12.9 gives a recommended bolt M10