Abstract: Coiled tubing optimized for long, horizontal completions is provided. The tubing comprises a body portion; at least two tapered portions, each tapered portion defining distal ends spaced apart from one another; and at least one bias weld portion. In some embodiments, the tapered portions are located between the body portion and the bias weld. The tubing has a weld thickness in the bias weld portion(s), a body thickness in the body portion, and a taper thickness in the tapered portions; generally, the thickness of the bias weld portion is greater than the body portion thickness. The wall thickness transitions from one end of each tapered portion to the other end of the same tapered portion.

Abstract: A method for manufacturing a long length of coiled metal tubing or the like using friction stir welding. Successive lengths of metal strip are friction stir welded using a three-pass welding technique to eliminate any edge defects in the resulting strip. The method includes one or more three-pass friction stir welding routines, each of which includes a first pass performed using a tool having a first rotational direction and a spiral bit pattern corresponding to the first rotational direction; a second pass using a tool having a second rotational direction and a spiral bit pattern corresponding to the second rotational direction; and a third pass using a tool having said second rotational direction and a spiral bit pattern corresponding to the second rotational direction.

Abstract: Coiled tubing optimized for long, horizontal completions is provided. The tubing comprises a body portion; at least two tapered portions, each tapered portion defining distal ends spaced apart from one another; and at least one bias weld portion. In some embodiments, the tapered portions are located between the body portion and the bias weld. The tubing has a weld thickness in the bias weld portion(s), a body thickness in the body portion, and a taper thickness in the tapered portions; generally, the thickness of the bias weld portion is greater than the body portion thickness. The wall thickness transitions from one end of each tapered portion to the other end of the same tapered portion.