McDermott successfully installs India’s Vashishta and S1 fields

27 April 2018 (Last Updated April 27th, 2018 09:34)

McDermott International has successfully completed the installation and start-up on the Vashishta and S1 fields in Andhra Pradesh, India.

McDermott successfully installs India’s Vashishta and S1 fields
For ONGC’s Vashishta project, the first-end pipeline end termination was lifted from the supply boat by NO 105. Credit: McDermott International.

McDermott International has successfully completed the installation and start-up on the Vashishta and S1 fields in Andhra Pradesh, India.

The projects are part of an engineering, procurement, construction and installation (EPCI) contract received by the company from India-based Oil and Natural Gas Corporation (ONGC) in December 2015.

Under the agreement, McDermott carried out the work on the project in collaboration with consortium partner LTHE, a wholly owned subsidiary of Larsen & Toubro (L&T).

Both McDermott and LTHE were responsible for the engineering, supply and installation of a series of pipeline end terminations (PLETs) and in-line tee structures (ILTs), a pipeline end manifold structure (PLEM), rigid jumpers and nearly 50km of umbilicals.

The pipeline structure includes 93km of 14in dual rigid pipelines extending from the shallow water shore line to a maximum water depth of 700m.

To complete the installation phase, McDermott International deployed three of its speciality vessels, Derrick Barge 30, Lay Vessel North Ocean 105 and North Ocean 102.

“To complete the installation phase, McDermott International deployed three of its speciality vessels, Derrick Barge 30, Lay Vessel North Ocean 105 and North Ocean 102.”

In addition, the company deployed its portable spoolbase at the LTHE base in Kattupalli, India, in order to fast-track the production of pipeline stalk to be loaded on to the installation vessels.

McDermott International Vashishta project director Ben Delves said: “Engineering design for the Vashishta project was no easy feat due to the iterative nature of the design process which had to reconcile many factors such as soil conditions, jumper / spool loads, connector capacities, in-place environmental loads, pipeline expansion loads, installation weather limitations, vessel envelope constraints and mission equipment constraints.”

The Vashishta field lies in water depths varying between 500m and 700m, and approximately between 31km and 35km from the Amalapuram coast in Andhra Pradesh.

The S1 field is located in water depths of 250m to 600m, and between approximately 26km and 29km from the coast.

While the Vashishta field is anticipated to generate 9.56 billion cubic metres (bcm) over a period of nine years, the S1 field is estimated to produce 6.22bcm over a period of eight years.