PSI - Issue 26

Vladimír Chmelko et al. / Procedia Structural Integrity 26 (2020) 417–421 Chmelko et al. / Structural Integrity Procedia 00 (2020) 000 – 000

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3. Conclusions

In this paper, the attention was paid to two parameters needed for numerical simulations of pipelines loaded with internal pressure. A simple bilinear material model was designed and based on measuring the contractual and actual tensile diagram of X52 steel. The conditions and the destruction criterion for local defects (unsupported weld roots, offset of welded pipe faces, small corrosion defects) were designed on the basis of verification with experimental results of pipe destruction tests. It can be said that the set conditions and criterion are related to the used material model. Confrontation with experimental results in combination with a suitably selected destruction criterion leads to a good correlation of destruction pressures with reality. The influence of local defects is not disqualifying in terms of safety of pressure pipeline operation. In the operation of older piping systems there are also other unprojected situations, such as geometric variances of the pipe from the circular shape, additional bending stress and others, whose synergy with local defects significantly reduces the safety of operation of pressure piping systems. The above-mentioned methodology of numerical simulations can also be used successfully to assess such complex situations.

Acknowledgements

This work was supported by the Slovak Research and Development Agency under the contract No. APVV-17 0666 and by the Research & Development Operational Programme funded by the ERDF ITMS: 26240220084 Science city Bratislava.

References

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