Bolt grips according to DIN 6914 and DIN EN 14399-4 have specific definitions.
- Bolt grip according to DIN 6914
The grip length according to DIN 6914 is calculated taking into consideration the thickness of the connected elements and the elements used for the connection.
The lk value appears in the properties window of the connection on the "Length" tab (e.g., 2x Bl10, HVM12 DIN 6914).
The connection washer thickness and the nut thickness are calculated using an integrated calculation method, by taking into consideration the bolt diameter, so that the correct bolt length are obtained.
- Bolt grip according to DIN EN 14399-4
The grip length according to DIN EN 14399-4 is calculated taking into consideration the thickness of the connection elements and the thickness of the washers.
Σt represents the grip length according to the modified form of DIN EN 14399-4.
On the "Length" tab in the properties window of the connection, for a bolt according to DIN EN 14399-4, only the thickness of the connection elements will be specified (e.g., 2 x Bl10, HVM12 DIN EN 14399-4).
The bolt grip length will be correctly specified because, as shown above, the thickness of the corresponding washers and the nut height are taken into consideration through the usual calculation method.
- Conclusion
Although the norm has been modified, by correctly specifying the bolt grip length, the final result remains correct.