The offshore HC Jacket is located in the Heera Field of ONGC Mumbai High at a water depth of 60.10 meter. During inspection the framing level, which is located at EL(-) 06.00 meters of the HC platform, was found to be detached. Dolphin Offshore Enterprises (India) Limited requested Nautec to replace the entire frame with a new frame through the application of grouted clamps methodology.
Scope
- Pre-Engineering; Inspection; In-place; Fatigue; Pushover and FEA analysis
- Supply/provision of grouting material NaX® Q140
- Supervision of installation of clamps
- Grouting facility; tools and equipment; engineer and grouting crew
- Cubes casting and testing
Challenges
- Due to the installation of numerous clamps that were all interconnected to form a single structure, grouting of single clamp was not possible, hence all the clamps were grouted in one go.
- Holding all the clamps together from start till finish of the grouting process was a huge task in itself and was made possible by installing the leg clamps one at a time, carefully following the sequence of installation.
- The job required intense rigging arrangements in order to hold all the clamps together.
Services
- Nautec provided engineering and grouting services for underwater member replacement of Level-C on HC platform using high performance cement NaX® Q140.
Client Benefits
- The entire level-C, located at (-) 06.00meters, was replaced with grouted clamps without any underwater welding or shut down of the platform.
- This structural repair was one of its kind in restoring the jacket strength to allowable margin of operation.
- All the deliverables were achieved with high quality performance, client acceptance and satisfaction.
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