SELFRAG AG is specialized in development of high voltage pulse power products, plants and systems for selective fragmentation of various solids.
For their voltage pulse system, SELFRAG AG engineers designed a new pressurized high voltage switch. CADFEM helped them to proceed pressure vessel analysis.
A FEM model of the complete pressure vessel was generated to complete the vessel assessment.
The FE-analysis with ANSYS combined with CADFEM expertise enabled engineers to save precious time and complete efficiently the vessel assessment.
The company SELFRAG AG is specialized in development, engineering and marketing of high voltage pulse power products, plants and systems for selective fragmentation of various solids. SELFRAG is focusing on scaling up the mineral processing levels required in the mineral industry. The objectives are to increase recovery and grade while decreasing energy consumption in the mining comminution circuit. For their voltage pulse system, SELFRAG designed a new pressurized high voltage switch. At the beginning of the design phase, CADFEM prepared a verification concept for the pressure vessel, which was approved by the certification authority Swiss TS. CADFEM performed then the verification analyses according to EN 13445 Appendix C by means of numerical methods.
The FE-analysis with ANSYS enables the assessment of unconventional designs within a single model, which was necessary for this specific application. The verification of the pressure vessel according to EN 13445 Appendix C, has the advantage that there is no need for a classification or linearization of the stresses, which saves engineering time during the evaluation of the FE results. The strength of the 174 bolts according to VDI 2230 were assessed efficiently by means of the CADFEM ANSYS Extension “Bolt Assessment inside ANSYS”, compared to a manual extraction and external evaluation of the bolt loads. Thanks to training on the specific project, SELFRAG AG is able to do the future verification analyses in-house.
A FEM model of the complete pressure vessel was generated, which considered the influence of the internal pressure, temperature, operating weight and bolt pretension. The pressure vessel was analyzed for:
- global plastic deformation
- progressive plastic deformation under cyclic loading
- stability of fiber reinforced tube by a nonlinear buckling analysis
- bolt strength according to VDI 2230
The strength of the pressure vessel was successfully verified with the proof pressure in an experimental test