Vibration induced fatigue failure prediction in process pipework / Norshahanis binti Zamahsari

The vibration in piping system has been a great threat in industry. This vibration has become a leading source of pipe failure especially in oil and gas industry with 21% of the pipework failure on the topsides facilities were due to vibration and fatigue failures in the North Sea of UK, reported by the UK’s Health & Safety Executive (HSE). Due to this, it is needed to verify whether the targeted area of observation really have high possibilities of flow induced vibration (FIV), earlier from designing stage. Other issues that need to be focused on are to identify best suitable means to reduce FIV and verify whether the recommended action is effective enough to reduce and cope failure in piping system. This research aims to identify potential FIV which can lead to fatigue failure if excessive. Following the guideline published by Energy Institute on the Avoidance of Vibration Induced Fatigue Failure (AVIFF), the assessment was done accordingly. From qualitative and quantitative assessment until the process of simulating the piping system through simulation software based on the recommended action identified, the processes were done following all the required steps. By calculation and detailed analysis, several lines were identified to have high failure potential. By using computational fluid dynamic (CFD) and finite element analysis (FEA), the simulation models of the piping system were produced. Changes to the pipe nominal diameter and wall thickness were applied to the effected lines. After changes applied, simulation was repeated with CFD tools and it was verified that changes made were able to reduce vibration on the line.