References¶
The documentation and the docstrings of the source code cite the following
documents as ref. [n]. The numbers are the same everywhere.
| Ref. | Document | Used for |
|---|---|---|
| [1] | Seidel, M.: IEC 61400-6 AMD1 Background document. Fatigue design for ring flange connections in wind turbine support structures. Rev00, Siemens Gamesa, 2024. | Background of the AMD1 model, design gaps, stochastic model (Table 7). |
| [2] | IEC 61400-6:2020+AMD1:2025 CSV. Wind energy generation systems - Part 6: Tower and foundation design requirements. Consolidated version, IEC, 2025. | The standard: design preload and losses (6.7.5.1), design gap (6.7.5.2), bolt force model (6.7.5.3 and Annex G), damage calculation (6.7.5.4). Equation numbers G.xx refer to Annex G. |
| [3] | Petersen, C.: Nachweis der Betriebsfestigkeit exzentrisch beanspruchter Ringflanschverbindungen. Stahlbau 67 (1998), pp. 191-203. doi:10.1002/stab.199800690 | Stiffness of the clamped parts. |
| [4] | Petersen, C.: Stahlbau. 4th edition, Springer Vieweg, 2012. doi:10.1007/978-3-8348-8610-1 | Stiffness of the clamped parts. |
| [5] | Seidel, M.: IEC 61400-6 AMD1 & ED2 Background document. Fatigue design for ring flange connections in wind turbine support structures. Rev01, draft 2026-08-04, Siemens Gamesa. | ED2 changes of the model (9.7), ED2 design gaps (2.2.4), stochastic model (6.4, Table 8), shell stiffness database (9.3.1). |
| [6] | Tobinaga, I.; Ishihara, T.: A study of action point correction factor for L-type flanges of wind turbine towers. Wind Energy 21 (2018), pp. 801-806. doi:10.1002/we.2193 | Action point correction a' (ref. [2], G.1.3). |
When a docstring cites a section or an equation, the number refers to the document cited: for example ref. [2], eq. G.36 is equation G.36 of IEC 61400-6:2020+AMD1:2025, and ref. [5], section 9.7 is section 9.7 of the Rev01 background document.
Availability
IEC 61400-6 can be purchased from the IEC webstore or from the national standardization bodies. The background documents are working documents of the IEC 61400-6 maintenance team; the Bolt & Beautiful project documentation is available from the project website.
Product and design standards¶
The bolt, nut and washer models of pyflange.bolts refer to:
- ISO 68-1:1998, ISO general purpose screw threads - Basic profile.
- ISO 724, ISO general-purpose metric screw threads - Basic dimensions.
- ISO 898-1:2013, Mechanical properties of fasteners - Part 1: Bolts, screws and studs.
- ISO 4032, Hexagon regular nuts (style 1).
- ISO 7089, Plain washers - Normal series.
- EN 1993-1-8:2005, Eurocode 3 - Design of steel structures - Part 1-8: Design of joints.
- VDI 2230 Part 1, Systematic calculation of highly stressed bolted joints.
Citing PyFlange¶
If you use PyFlange in a report or a publication, please cite it as:
PyFlange: Python library for the analysis of large bolted ring-flange connections. KCI The Engineers B.V., Siemens Gamesa Renewable Energy B.V., TNO, developed within the Bolt & Beautiful GROW project. https://github.com/kcibv/pyflange, version x.y.z.
and state the version you used (py -m pip show pyflange).