Connecting assembly and method

An assembly for communicating a first location with a second location, wherein said assembly extends through a body of fluid, comprising:

• (a) first tube means extending continuously generally between said first location and said second location;
• (b) second tube means positioned generally within said first tube means;
• (c) first anchor means and second anchor means for anchoring said second tube means to said first tube means at two positions and for thereby maintaining said second tube means under tension;
• (d) seal means for at least partially closing off an area generally defined between the inner surface of said first tube means and the outer surface of said second tube means;
• (e) fluid means;
• and
• (f) pump means for selectively adjusting and maintaining said fluid means in said area in quantity and density to selectively control the buoyancy of said assembly relative to said fluid body.

A method of providing a connection between a first location and a second location, between which locations a body of fluid is located, comprising the steps of:

• (a) extending a first tube means between said first location and said second location, through said body of fluid;
• (b) positioning a second tube means generally within said first tube means, and anchoring said second tube means to said first tube means at two separated positions with said second tube means under tension greater than that of said first tube means;
• (c) at least partially fluid sealing said second tube means to said first tube means;
• and
• (d) selectively controlling the density and amount of liquid in the area generally between the inner surface of said first tube means and the outer surface of said second tube means to one side of said sealing by pumping liquid into or out of said area.

A method of operating on an underwater well from a marine drilling facility comprising the steps of:

• (a) flexibly joining a riser tube at the drilling facility and at the well site;
• (b) positioning a liner generally within the riser tube and anchoring the liner, near its lower end, to the riser tube;
• (c) pulling up on the liner and, while the liner is thus stressed, anchoring the liner, near its upper end, to the riser tube against downward movement relative to the riser tube, leaving the liner under tension;
• (d) fluid sealing the liner to the inner surface of the riser tube generally at the lower end of the liner, thereby defining a generally annular region between the outer surface of the liner and the inner surface of the riser tube, extending generally upwardly from the fluid seal;
• and
• (e) selectively controlling the buoyancy of the riser tube and its contents by adjusting the density or amount, or both, of liquid within the generally annular region.

A method of drilling an underwater well from a marine drilling facility comprising the steps of:

• (a) connecting the drilling facility with the well site by a riser tube, flexibly joined to the drilling facility at the top of the riser tube, and flexibly joined to the well site at the bottom of the riser tube;
• (b) positioning a liner generally within the riser tube and anchoring the bottom of said liner against upward movement relative to the riser tube;
• (c) applying generally upwardly directed force to said liner to place said liner under tension;
• (d) anchoring the top of said liner against downward movement relative to said riser tube while said liner is so under tension;
• (e) drilling the well bore by a drill bit directed by a drill string extending from the drilling facility down through the liner to the well site;
• and
• (f) circulating drilling fluid from the drilling facility down through the drill string, out into the well bore, up through the riser tube and liner surrounding the drill string, and back to the drilling facility.

A method of drilling an underwater well from a marine drilling facility comprising the steps of:

• (a) connecting the drilling facility with the well site by a riser tube, flexibly joined to the drilling facility at the top of the riser tube, and flexibly joined to the well site at the bottom of the riser tube;
• (b) positioning a liner generally within the riser tube, anchoring the bottom of said liner against upward movement relative to the riser tube, and fluid sealing the liner to the riser tube at the bottom of the liner to define a generally annular region between the inner surface of the riser tube and the outer surface of the liner and extending generally upwardly from the fluid sealing;
• (c) applying generally upwardly directed force to said liner to place said liner under tension;
• (d) anchoring the top of said liner against downward movement relative to said riser tube while said liner is so under tension;
• (e) providing at least one jet line extending downwardly into the generally annular region;
• (f) providing a gas inlet line, for each jet line, also extending downwardly into the generally annular region and positioned so that gas may communicate out of the one or more gas inlet lines into the corresponding one or more jet lines;
• (g) controlling the buoyancy of the riser tube and its contents by selectively communicating gas down the one or more gas inlet lines and into the corresponding one or more jet lines to aerate liquid within the one or more jet lines to permit said aerated liquid to be propelled upwardly by liquid of larger density;
• (h) drilling the well bore by a drill bit directed by a drill string extending from the drilling facility down through the liner to the well site;
• and
• (i) circulating drilling fluid from the drilling facility down through the drill string, out into the well bore, up through the liner surrounding the drill string, and back to the drilling facility.