Marine Warranty: Experience of Angola's Largest Deep Water Development by Dr. Tanmay Sarkar, DNV GL


Marine Warranty Experience of Angola’s Largest Deep-Water Development

Tanmay Sarkar, DNV GL

Kaombo is the first ultra-deep water project located in Block 32 of the coast of Angola. Situated at maximum water depth of 1,950 m with oil reserve of 658 million barrels and spread across 800 square kilometres which is eight times the size of Paris Kaombo is the largest subsea development for Total to date.





Kaombo has a particularly complex production system where oil deposits are spread across six fields, has 59 wells which is the largest well system for a single project. Two hundred ninety kilometres of pipeline connect six group of wells to two FPSO.

Project involved fabrication, transportation and hook up two VLCC converted FPSOs, transportation and installation of 290km of line pipe (6 hybrid production loops, 5 water injection and 1 gas export lines), 80 FLETs, 17 ILTs, 115km of umbilical, 59 vertical Xmas trees, 20 production manifolds, 18 upper  riser assemblies, 18 lower riser assembiliess,18 buoyancy tanks, 52 rigid spools, 8 water injection jumpers and several suction piles. Items were fabricated worldwide in a truly global project footprint with fabrication yards and production facilities based in Angola, Spain, Sharjah, UK, France and USA. Two VLCC conversions to FPSO took place in Singapore with modules fabricated in Indonesia and Turret in UAE which are then transported to Singapore for integration.

In February 2015, a consortium of Noble Denton marine service (NDms) DNVGL and DNV Angola Servicos Limitada was selected to perform marine warranty services by Total E&P Angola (TEPA) for this technically and logistically challenging project. This presentation will detail how NDms led consortium met the challenges successfully to the fullest satisfaction of TEPA thereby setting a benchmark of delivery of Marine Warranty services for future deep-water projects of similar volume and content in West Africa.

On award of the contract NDms formed a global project team with highly competent engineers and mariners. Technical review and project management was done centrally from London while attendances were performed from our local and in-country offices. This served twin purpose of reducing cost and making sure faster response locally to project needs. Centralized technical review and project management ensured coordinated delivery and quality control. Regular communications, meetings and briefing of on-site surveyors/local co-ordinators with project management team enabled our local team sufficiently briefed about key issues and concerns before mobilizations. Review of each document by competent mariners and engineers, development of project specific checklists, suitability survey of all equipment and vessels enabled us to successfully deliver Marine Warranty scope and contribute towards identification of pitfalls in proposed analyses and procedures, suggesting improvements and contributing towards project’s success.

Project also developed a successful first-in-series attendance procedures for many key products. These procedures were developed with active collaboration between NDms, TEPA (Total E&P Angola) and installation contractors. This method enabled substantial cost savings without jeopardizing safe operations.

Logistical challenges of mobilization in Angola was greatly negated by having MWS permanent presence in Angola during key operations of the project. Implementation of this scheme also reduced mobilization costs.

One of the key successes of the project was development of local resources in MWS skill. Two of DNV GL Angola employees were trained in MWS skills by a combination of theoretical and practical trainings. Initial part of the training was imparted in London while practical aspects were achieved by having them working in the project where Permanent presence personnel also played a key role in Angolan part of the training.

In course of execution of this project in total 1,399 Technical Review Notes (TRNs) were issued with approximately 7,000 comments, 113 vessels were surveyed for suitability on the project, OVID surveys were performed for 28 vessels, total no of mobilizations were 179 for FPSO and 50 for SURF. In addition to 50 SURF mobilisations there was also 12 months of continuous attendance by MWS Permanent Presence in Angola covering mainly SURF MWS work.  In total 510 Certificates of Approvals (CoA’s) were issued, while 295 CoA’s for FPSO and 215 CoA’s for SURF. These statistics show the vastness and complexity of the project.

This presentation will also detail several lessons learned during execution of this project. Overall this is an extremely successful project in terms of Marine Warranty with only a few minor incidents during marine operations. This Project set up a model in effective execution of first-in-series techniques to reduce cost without compromising quality and use of permanent presence to reduce cost and meet logistical challenges of projects in Angola. Throughout the project MWS has shown how a proactive PM (project management) team can lead to successful delivery of Marine Warranty services without compromising interests of the underwriters. Agility and competence of MWS team were two key elements of success and highly commended by TEPA.


Tanmay Sarkar – Head of Section, Marine Warranty UK & West Africa, DNV GL

 Tanmay is a Naval Architect/Subsea Engineer by profession and Ph.D from University of Strathclyde, UK and a Certified Project Management Professional(PMP) of Project Management Institute. He is also a Chartered Engineer and member of Royal Institution of Naval Architects. Tanmay is Technical Authority for Submarine Pipeline Installation in Technical Standards Committee of Noble Denton marine services, DNV GL and instrumental in publishing DNV GL’s first ever guideline for Submarine Pipeline Installation and Section 7 of Standard N001.  He is currently Head of Section of Marine Warranty UK and West Africa within DNV GL.  Tanmay has several years of experience in offshore industry working mainly in areas of offshore installation. He has in recent years managed marine warranty scope of several mega subsea projects in West Africa. Notable among them are Tullow TEN in Ghana, CLOV, GirRI Phase I & II and Kaombo in Angola. He has contributed largely in successful completion of marine operations of these projects.


When:  Oct 20, 2020 from 6:00 PM to 7:00 PM (GB)
Associated with  Western Europe
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Lourdes Elona-Lilley
+44 7479639770