How the calculator works.
The lifting-lug calculator runs public-domain mechanics checks on single-plate lugs alongside the code routes it has activated — ASME BTH-1-2020 §3-3.3, EN 1993-1-8:2005 §3.13, and DNV-ST-N001:2020 §16. The methodology route you select drives the governing utilisation; the other families appear as cross-checks. Every implemented check names its source reference, edition and clause, and is guarded by a hand-computed validation case.
Standards strategy
Public-domain mechanics plus the active code routes: ASME BTH-1-2020 §3-3.3 / §3-3.4.3, EN 1993-1-8:2005 §3.13, and DNV-ST-N001:2020 §16. Every check traces to an edition and clause number.
Validation cases
Hand-computed benchmarks for every active family. Every benchmark is re-run before each release; drift outside the stated tolerance blocks the release.
Demo report
Example of the printable report: primary checks from the selected methodology, cross-checks from the other frameworks, assumptions and source traceability.
Methodology
The calculator iterates a registry of checks. Each check is a deterministic function of the inputs — the same configuration always produces the same result. Checks are composed into a governing-check selection, an overall utilisation, warnings from the out-of-scope rules, and a list of assumptions used by the checks that ran.
Internal units
Internal canonical units are SI: Newtons (N), millimetres (mm), megapascals (MPa). US customary display is a UI-level conversion only — the engine never operates in mixed units.
Scope
- Single-plate lugs / padeyes. Cheek-plate configurations are out of scope for v1.
- In-plane load application. Lifting angles above 30° trigger a scope warning and a recommendation to use a detailed method.
- Linear-elastic, isotropic plate material. Fatigue, residual stress, and plastic redistribution are not modelled.
- Code-specific partial factors, Nd values and DAF/SKL defaults apply only when the matching methodology route is selected. The mechanics-of-materials route uses user-supplied allowables and no code-specific coefficient.