Sarens has supported Subsea7 with the installation of the three topsides for Aramco’s Marjan Increment Program package 2 field development offshore Saudi Arabia.
The project involves the addition of new oil, water and gas injection platforms and construction of a new offshore oil and gas separation plant (GOSP-4). Subsea7 and Larsen & Toubro (L&T) are managing the EPCIC scope under a long-term agreement with Aramco.
The three TP topsides were installed via the floatover method, with Sarens supplying a mooring system for the operation.
Following transportation of the winches and associated equipment from Belgium to the port of Mundra in Mumbai, they continued by road to L&T's Hazira fabrication yard where the topsides were loaded out onto a floatover barge.
Marjan package 2 offshore oil facilities will help raise total oil processing capacity from the field from 600 to 800,000 bbl/d. The field is 85 km northeast of Tanajib and 260 km northeast of Dhahran, in water depths of 29 m to 52 m.
For the TP11, TP12 and TP13 topsides, Sarens’ mooring equipment included a cross wire winch, cross wire dyneema cable, docking line winch, docking winch dyneema cable, hydraulic power unit, line tension monitor, tugger winch, tugger cable, and directional aids such as a swivel guide and a universal roller guide.
The selection was based on floatover engineering simulations, including the winch capacity required for positioning the floatover barge during docking and mating operation phases.
Other factors were the not-to-exceed (NTE) weight for transport and installation (T&I) engineering of 4,800 metric tons for the TP11 and TP12 topsides, and 5,800 mt for the TP13 topsides. The NTE weight excludes temporary T&I elements such as gratings and sea fixings.
Sarens dispatched a supervisor and a technician to oversee installation and commissioning of the mooring winches, barge draft sensor system and auxiliary equipment on the floatover barge at the Hazira yard.
The vessel then sailed with the first topsides to the Marjan installation location, with Sarens personnel onboard for the offshore campaign to operate the winches for positioning the barge during docking/mating operations.
This process was repeated for the second and third topside. All three topsides have been installed.
