For bolts screwed into soft materials (e.g., aluminum $\le 200$ MPa tensile strength), VDI 2230:2021 mandates a minimum engagement length $m = 2.0 \times d$ for coarse threads and $1.8 \times d$ for fine threads, unless a thread stripping check proves otherwise.
The VDI 2230 guideline, titled "Systematic calculation of highly stressed bolted joints," has long served as the international benchmark for the analytical calculation of multi-purpose bolted joints. The 2021 update represents a significant technical evolution, refining the methodology to account for the increasing complexity of modern engineering materials and the demand for higher safety margins in lightweight construction. 1. The Core Philosophy and Scope vdi 2230 2021
Unlike simpler models, VDI 2230 offers analytical calculations for eccentric loads using a "load factor" to account for changes in resilience and the load application point. Integration with Modern Simulation For bolts screwed into soft materials (e