Vdi 2230 2021 -

In earlier editions, $n$ was a discrete integer (1,2,3). The 2021 edition allows fractional $n$ based on FEA validation. For example, a joint where the load is introduced 30% under the head and 70% at the nut can now be modeled precisely.

): This accounts for the scatter in preload depending on the tool used (e.g., torque wrench vs. hydraulic tensioner). vdi 2230 2021

: The guideline now provides more detailed guidance on the design and calculation of joints with non-standard bolts, reflecting the increasing use of specialized fasteners in modern engineering applications. In earlier editions, $n$ was a discrete integer (1,2,3)

Do not calculate manually for complex joints. These tools have integrated the 2021 revision: In earlier editions