An apparatus enables modifying a riser's operating parameters for transporting production fluids from a subsea well to an offshore production facility after an initial period of production to address changes over time in the conditions of the reservoir and/or the riser without removing the original riser. An insert riser having a smaller diameter is inserted into the riser after the initial period. The original riser has a recessed seal face for receiving seal element(s) and a recessed lock groove for receiving a locking ring. An intervention coiled tubing having a sleeve removal tool is inserted into the riser to engage a protective sleeve covering the recessed seal face. The tubing is pulled to the floating structure thereby removing the protective sleeve and the temporary retaining ring from the production riser, exposing the recessed seal face. The insert riser can then be inserted into the riser and locked into place.

The present invention pertains to a multilayer tubular article, to processes for the manufacture of said multilayer tubular article and to uses of said multilayer tubular article in upstream applications for conveying hydrocarbons from a well to a floating off-shore unit via a bottom platform.

The present invention pertains to a multilayer tubular article, to processes for the manufacture of said multilayer tubular article and to uses of said multilayer tubular article in upstream applications for conveying hydrocarbons from a well to a floating off-shore unit via a bottom platform.

A method of manufacturing marine riser buoyancy elements includes providing a master mold and mold inserts such that a range of buoyancy elements may be manufactured from one master mold and providing the mold inserts such that an annular space between the riser main conduit and the buoyancy elements, or a groove width between the buoyancy elements may be varied during manufacture.

A subsea support system comprises: at least one component (501) which is configured to be fixedly connected to a pressure conductor (101) in a seabed; and a subsea support (601) which is configured to compliantly support the at least one component (501); wherein, when the at least one component (501) is fixedly connected to the pressure conductor (101), substantially all of a mechanical load (T) which is applied to the subsea support (601) is transmitted by the subsea support (601) to the seabed while the at least one component (501) is substantially free of the mechanical load and remains fixed relative to the pressure conductor (101).

A subsea support system comprises: at least one component (501) which is configured to be fixedly connected to a pressure conductor (101) in a seabed; and a subsea support (601) which is configured to compliantly support the at least one component (501); wherein, when the at least one component (501) is fixedly connected to the pressure conductor (101), substantially all of a mechanical load (T) which is applied to the subsea support (601) is transmitted by the subsea support (601) to the seabed while the at least one component (501) is substantially free of the mechanical load and remains fixed relative to the pressure conductor (101).

The present invention relates to a method and apparatus for cleaning an oil and gas well riser section or assembly on location offshore that includes a larger diameter central pipe and a plurality of smaller diameter pipes that are spaced radially away from the central larger diameter pipe. Even more particularly, the present invention relates to an improved method and apparatus for cleaning oil and gas well riser sections wherein a specially configured cap or pair of caps are fitted to the ends of the riser which enable pressure washing cleaning tools (or a camera) to be inserted into and through a selected one of the pipes including either a smaller diameter of the pipes or the central larger diameter pipe and wherein the cap continuously collects spent cleaning fluid and debris, allowing the cleaning process to be done on location without transporting the riser section back onshore.

The present invention relates to a method and apparatus for cleaning an oil and gas well riser section or assembly on location offshore that includes a larger diameter central pipe and a plurality of smaller diameter pipes that are spaced radially away from the central larger diameter pipe. Even more particularly, the present invention relates to an improved method and apparatus for cleaning oil and gas well riser sections wherein a specially configured cap or pair of caps are fitted to the ends of the riser which enable pressure washing cleaning tools (or a camera) to be inserted into and through a selected one of the pipes including either a smaller diameter of the pipes or the central larger diameter pipe and wherein the cap continuously collects spent cleaning fluid and debris, allowing the cleaning process to be done on location without transporting the riser section back onshore.

An extension member for coupling a tapered stress joint to a basket coupled to a porch extending from an offshore platform is disclosed. In an embodiment, the extension member includes a central axis, a first end, and a second end opposite the first end. In addition, the extension member includes a radially inner surface extending axially from the first end to the second end. The inner surface includes a first mating profile proximate the first end that is configured to engage a radially outer surface of the tapered stress joint. Further, the extension member includes a radially outer surface extending axially from the first end to the second end. The outer surface includes a second mating profile proximate the second end that is configured to slidingly engage a mating profile within the basket.

Systems and methods for hydrofluoric (HF) acidizing compositions compatible with sensitive metallurgic grades. The systems and methods may include preparing an aqueous acidizing composition comprising one or more acid components, hydrofluoric acid, and one or more corrosion inhibitors; and injecting the aqueous composition into a subterranean formation containing sensitive metallurgic components via a wellbore.