The minimum thread length is calculated strictly according to:
- EN 14399-3 for high-strength structural bolting assemblies for preloading (System HR)
- EN 14399-7 for high-strength structural countersunk bolting assemblies for preloading (System HR CSK)
- EN 14399-4 for high-strength structural bolting assemblies for preloading (System HV)
As a part of High-strength structural bolting assemblies for preloading.
In calculation, you need to consider standard reference thread length (b), minimum length of the shank - un-threaded part of the bolt, and distance from the head of the bolt till the first full thread.
To help with that, we have created some useful calculators.
- Thread Length Calculator for HR Bolts to EN 14399-3
- Thread Length Calculator for HR Countersunk Bolts to EN 14399-7
- Thread Length Calculator for HV Bolts to EN 14399-4
In any doubts, please contact our Quality Department.