This page shows the essential information about a bolt connection (through-hole with a bolt inserted through it) with the following components:
- Bolt DIN EN ISO 4014
- Nut DIN EN ISO 4032
- Washer DIN EN ISO 7089
This page serves as a guide when selecting suitable screws and represents an excerpt or compiled information from the various standards, but does not replace a proof of strength for a screw connection.
Section view of the bolt connection
Characteristics of the bolt connection
| Parameters, geometrical | Symbol | Unit | Standard | M3 | M4 | M5 | M6 | M8 | M10 | M12 | M16 | M20 |
| Pitch | p | mm | ISO 261 | 0,5 | 0,7 | 0,8 | 1 | 1,25 | 1,5 | 1,75 | 2 | 2,5 |
| Head height | a | mm | DIN EN ISO 4014 | 2 | 2,8 | 3,5 | 4 | 5,3 | 6,6 | 7,5 | 10 | 12,5 |
| Washer thickness | b | mm | DIN EN ISO 7089 | 0,5 | 0,8 | 1 | 1,6 | 1,6 | 2 | 2,5 | 3 | 3 |
| Diameter of the through hole | c | mm | DIN EN 20273 (middle) | 3,4 | 4,5 | 5,5 | 6,6 | 9 | 11 | 13,5 | 17,5 | 22 |
| Inner diameter of the washer | d | mm | DIN EN ISO 7089 | 3,2 | 4,3 | 5,3 | 6,4 | 8,4 | 10,5 | 13 | 17 | 21 |
| Thread length | e | mm | DIN EN ISO 4014, l <= 125 mm | 12 | 14 | 16 | 18 | 22 | 26 | 30 | 38 | 46 |
| Thread length | e | mm | DIN EN ISO 4014, l <= 200 mm | 44 | 52 | |||||||
| Head height of the nut | f | mm | DIN EN ISO 4032 | 2,4 | 3,2 | 4,7 | 5,2 | 6,8 | 8,4 | 10,8 | 14,8 | 18 |
| Outer diameter of the washer | g | mm | DIN EN ISO 7089 | 7 | 9 | 10 | 12 | 16 | 20 | 24 | 30 | 37 |
| Parameters, mechanical | Strength class | |||||||||||
| Minimum breaking force of the bolt connection | kN | 5.6 | 2,51 | 4,39 | 7,1 | 10 | 18,3 | 29 | 42,2 | 78,5 | 122 | |
| kN | 8.8 | 4,02 | 7,02 | 11,35 | 16,1 | 29,2 | 46,4 | 67,4 | 125 | 203 | ||
| kN | 10.9 | 5,23 | 9,13 | 14,8 | 20,9 | 38,1 | 60,3 | 87,7 | 163 | 255 | ||
| kN | 12.9 | 6,14 | 10,7 | 17,3 | 24,5 | 44,6 | 70,8 | 103 | 192 | 299 |
