Abstract An apparatus for use in drilling maintaining and servicing an oil or gas well comprising a sealed chamber supported below the water level but above the sea-bottom on a pile driven into the bottom. A number of well casings having their upper ends within the chamber project into the sea-bed, and their upper ends carry well-head control valves for controlling the oil or gas flow from the well casings. The chamber can be constructed in two parts, namely a bottom or platform part which is attached to the pile after the pile has been driven into the sea-bed and which provides apertures to allow the well casings to be passed through on to the sea-bed and driven, and an upper portion which has an access pipe leading to a point above the surface and which is sealingly secured to the platform part after the wells have been drilled.
A method of drilling an underwater oil or gas well comprising the steps of driving a single vertical tubular pile into the water bed, the pile initially extending above the water level from the water bed and being operated on above the water level to drive it into the water bed, the upper portion of the pile being then cut off under water at a selected height above the water bed and removed, securing an apertured guide platform to the top of the remaining portion of the pile under water, which platform has at least one guide aperture therein arranged outwardly of the pile, passing a well conducting casing through said guide aperture and into the bed, drilling the well through the conducting casing, Attaching a well head unit to the upper end of the casing just above the platform, permanently attaching an upper portion to the platform to form therewith a chamber below the water surface, which chamber encloses the well head unit, the upper portion having secured thereto an access shaft which extends upwards above the water surface, and pumping the water out of the chamber and access shaft.
Claim 2
Independent Claim
191 words
A method of drilling an underwater oil or gas well comprising the steps of driving a single vertical tubular pile into the water bed, the pile initially extending above the water level from the water bed and being operated on above the water level to drive it into the water bed, the upper portion of the pile being then cut off under water at a selected height above the water bed and removed, securing an apertured guide platform to the top of the remaining portion of the pile under water, which platform has at least one guide aperture therein arranged outwardly of the pile, passing a well conducting casing through said guide aperture and into the bed, drilling the well through the conducting casing, Attaching a well head unit to the upper end of the casing just above the platform, permanently attaching an upper portion to the platform to form therewith a chamber below the water surface, which chamber encloses the well head unit, the upper portion having secured thereto an access shaft which extends upwards above the water surface, and pumping the water out of the chamber and access shaft.