A full VDI 2230 through-bolt joint (DSV) worked example, going through R0–R13 in all 14 steps. It includes the specific input parameters, the intermediate result of each step and the final safety factors, ties the theory of the previous 7 articles into one calculation chain, and lists every input you need to re-run the case in the calculator.
The lower half of the VDI 2230 calculation chain — six strength checks (assembly stress, service stress, fatigue, bearing pressure, engagement depth, slip) plus the tightening torque R13. Each check's physical meaning, formula and safety factor explained one by one.
The upper half of the VDI 2230 calculation chain R1–R6 explained: the tightening factor αA, the three sources of the minimum clamping force FKerf, the choice of force-ratio Φ formula, preload loss (embedding + thermal expansion), and the derivation of the minimum and maximum assembly preload.
VDI 2230 uses an equivalent deformation cone (Ersatzverformungskegel) to model the compression zone of the clamped parts. This article explains the cone-angle formula, the cone-plus-sleeve combined model, multi-layer plate handling, and the key differences between DSV and ESV.
VDI 2230 breaks a real bolt into a chain of series cylindrical segments to compute its total elastic resilience δS. This article walks through the substitutional lengths and resilience formulas of the head, shank, free thread, engaged thread and nut region one by one, and explains the difference between DSV and ESV.
A detailed look at the core physical model of VDI 2230: the spring model (Federmodell), the elastic resiliences δS and δP, the joint diagram (Verspannungsschaubild), the physical meaning of the force ratio Φ, and the full derivation logic of the main equation Eq.16.
The applicability conditions of VDI 2230 Blatt 1, the interface limiting dimension G, the family of standards it depends on, and the implicit premise about how force is transmitted. Making clear what the standard can and cannot compute, so you avoid applying it blindly in the wrong scenario.
VDI 2230 is the globally recognized standard for the systematic calculation of high-strength bolted joints. This article explains the shortcomings of a simple strength check, the 14-step VDI 2230 calculation chain and the physical meaning of its main equation, to help engineers see why systematic bolt calculation is necessary.
Why does a bolted joint fail as a whole when the surface is only crushed a tiny bit? This article uses the model of a 'stretched rubber band clamping a sponge' to see through the mechanics of the bearing-pressure check: from microscopic peak crushing and macroscopic embedding (Setzen), to the elastic recoil that causes an irreversible loss of preload (clamping force), to the chain failure of loosening and fatigue fracture — and gives engineering measures such as controlling the limiting surface pressure and enlarging the bearing area.
Where does the reduction factor κ in bolt pre-selection come from? Starting from the two-way stress state where axial tensile stress and torsional shear stress combine during tightening, this article uses the von Mises yield criterion to derive the definition, formula and engineering values of κ, explaining how thread friction acts like an 'invisible tax' that cuts the bolt's axial load capacity, and why it appears in the denominator of the Kübler equation.