OFFSHORE WELL FOR OIL AND GAS RECOVERY WITH ABOVE-WATER PLACEMENT OF WELLHEAD EQUIPMENT Russian patent published in 2015 - IPC E21B43/01 

FIELD: oil and gas industry.

SUBSTANCE: surface well for oil and gas recovery at open sea comprises marine riser and wellhead placed at offshore platform complete with column head and X-mas tree equipment mounted on it including casing head and X-mas tree with gate valves equipped with actuators coupled to the control centre. Case of the column head is connected to a conductor placed inside the respective marine riser. In the column head at slip hanger the production string is suspended with tubing string installed in it and equipped with subsurface equipment. The marine riser is run in below the sea bottom to the depth covering the area of caving rock. The upper end of the marine riser is placed over the offshore platform deck below the casing head, and the conductor is run in up to the depth of shale break and fixed in solid clay rock. The production string placed in vertical part of the borehole is complete with s shank run in up to the roof of producing formation. The following equipment is used as subsurface equipment of the tubing string: wellhead shutdown valve, circulating valve, column disconnector, production packer with a landing nipple and gas lift mandrel placed under it, at that the above mandrel comprises measurement tools such as pressure and temperature sensor. The wellhead shutdown valve is designed for remote control option, and tools measuring pressure and temperature of produced fluid are designed to transmit data.

EFFECT: improved reliability of the well construction.

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