Centrica’s F3-FA SIP, the largest platform of its kind, is designed to operate for around 20 years. It is built to comply with the strict regulations imposed for operations in the Dutch and UK sections of the North Sea. The platform will be transferred to other prospects when production halts from the current field. The SIP is provided with facilities for separation of gas, condensate and water, and compressing the gas before being exported onshore. It has capacity to treat three million cubic metres of gas per day, 400m³ of condensate and up to 150m³ of water. The platform’s topside is composed of a cellar deck, a main deck and a top deck. It further features four sub-decks, including a mezzanine deck, an intermediate deck, a heli-deck and a weather deck. The platform provides accommodation facilities for 18 people on the main and intermediate decks.

The cellar deck is fitted with equipment required for the operation of the platform while the mezzanine deck accommodates the control rooms. The platform can also be remotely operated from Centrica’s J6-A production platform. The platform is supported by four tubular legs, which are further supported by four huge suction piles on the seabed. The platform was attached to the legs with 16 M240 superbolts, 16 studs of around five metres and 16 special locknuts, using the cup and ball bearing method. The platform is designed to drill three wells through one of its 3.25m-diameter tubular legs. A ten-inch gas export riser passes out through one of the other legs, which is also equipped with a ten-inch riser for possible future imports. The pressure required to transport the gas from the field is provided by a Solar Centaur 40 compressor turbine.

Two gas-fuelled generators with a capacity of 347kW each and a 500kW back-up diesel generator provide the required power to operate the platform. Safety equipment onboard the platform includes a diesel hydraulic fire pump, an electrically driven fire water pump and a free-fall lifeboat with capacity for 32 people.

Centrica’s F3-FA SIP’s topside weighs 4,000t and is 30m-long, 50m-wide and 30m-high. Each of the platform’s suction piles is 13m-long, has a diameter of 15m and weighs 400t. The platform’s legs are 75m-long, have a diameter of 3.5m and weigh 375t each. The stiffening frames weigh 425t each, while the overall weight of the platform is 9,500t. The platform was installed employing the Boa 35 transportation barge, three tugs and a diving support vessel (DSV). Installation works were completed in September 2010.