초록 ▼

A coil tubing string for injecting fluids into a well includes one or more tapered wall tubing sections welded in series with adjacent straight wall tubing sections to form smooth joints therebetween. The tubing string has tubing sections of dissimilar wall thicknesses. Such tapered wall tubing sect

A coil tubing string for injecting fluids into a well includes one or more tapered wall tubing sections welded in series with adjacent straight wall tubing sections to form smooth joints therebetween. The tubing string has tubing sections of dissimilar wall thicknesses. Such tapered wall tubing sections are used to connect tubing sections of dissimilar wall thicknesses wherein the transitions from one tubing section to another is smooth and continuous as one progresses from a thin wall tubing section to a heavy wall tubing section in an ascending order.

대표청구항 ▼

Well tubing for providing fluid communication between the surface and a preselected location in a well, comprising: an elongated coilable cylindrical member having a length defined by a first end supportable at the surface of said well and a second end positionable at a preselected location in said

Well tubing for providing fluid communication between the surface and a preselected location in a well, comprising: an elongated coilable cylindrical member having a length defined by a first end supportable at the surface of said well and a second end positionable at a preselected location in said well, said elongated cylindrical member being provided with a flow passageway to place said first end in fluid communication with said preselected location in said well; said elongated cylindrical member having a substantially constant outer diameter along its entire said length and an inner diameter that increases smoothly from said first end to said second end; and support means for supporting said elongated cylindrical member in said well solely by suspending said first end of said elongated cylindrical member, said cylindrical member being unsupported from immediately below said support means to said second end.