PSI - Issue 14

Praveen Bhat et al. / Procedia Structural Integrity 14 (2019) 656–663 Praveen Bhat, S. Karunanithi/ Structural Integrity Procedia 00 (2018) 000 – 000

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yard expenses and time duration for carrying out strengthening and refurbishment activities. It was found that around 20% cost savings can be achieved if the modifications are carried out in offshore itself ( Ref. 4 & 5 ).

6. Conclusion The preliminary analysis indicate that the existing platforms can be reused at the proposed new locations, through refurbishment & strengthening of existing structure, and installation of new plinth platform, as & if required. This innovative project is first of its kind in the Indian sub-continent. A methodology has been developed for platform relocation in western offshore of India including both decommissioning and refurbishment aspects (Figure 5). The feasibility study reveals that the three platforms A, B & C are re-locatable to new proposed locations; Y, X & Z respectively. The results presented in the paper may be required to be updated in view of considering the actual soil data for the finalized re-location based on the actual soil investigation report. The use of existing platform would help achieve substantial savings on account of non-requirement of new platform and realizing early monetization from the new offshore fields. Also, cost savings in view of not requiring disposal of non-producing platform in sea or at on-shore site would be achieved. In addition, good amount of savings can be realized if the strengthening/refurbishment requirements are met with in offshore than mobilizing the We acknowledge the support and resources provided by ONGC required for carrying out the feasibility study for ascertaining the structural adequacy of existing fixed jacket platforms for relocation to new fields. The study has been immensely beneficial in understanding the pertinent issues relevant to the relocation of existing platforms including abandonment and decommissioning aspects. We are immensely grateful for the continuous motivation received from Shri Dinesh Kumar, ED-Head of Structures Section, IEOT-ONGC. We also extend our sincere thanks to Shri C. Tandi, ED-Head Of Institute, IEOT-ONGC for his generous support and encouragement. References Recommended Practice for Planning, designing and Constructing Fixed Offshore Platforms-Working stress Design (API-RP-2A-WSD 21st edition) Re-qualification Methodology for fixed offshore platforms in west Coast of India, IEOT-Document number: IEOT-LIFE-001. IHS Markit 2016 study on Decommissioning of Aging Offshore Oil and Gas Facilities Dr. Robert C. Byrd, PE, Donald J. Miller and Steven M. Wiese, 2014. Cost Estimating for Offshore Oil & Gas Facility Decommissioning, 2014 AACE® international technical paper Twachtman Snyder & Byrd Inc., 2007, Draft report on Feasibility and cost estimation on abandonment of offshore platforms, study for ONGC structure to the yard. Acknowledgement