Method of conducting a coiled tubing operation

A method of conducting a coiled tubing operation, comprising:

• forming a coiled tubing string, the coiled tubing string having an outer surface and being formed from a metallic material;
• selecting an application portion of the coiled tubing string that corresponds to a horizontal section of a wellbore and a vertical section of the wellbore once the coiled tubing string is positioned in a fully deployed state within the wellbore, wherein the application portion does not include axial length of the coiled tubing string corresponding in the fully deployed state to a curved section of the wellbore disposed between the horizontal and vertical sections;
• applying a coating to the outer surface of the coiled tubing string only along the application portion, wherein the coating has a surface energy lower than a surface energy of the outer surface of the coiled tubing string to thereby reduce friction between the tubing coiled string and a casing disposed in the horizontal section of the wellbore as the coiled tubing string is lowered into the wellbore, wherein the coating has a thickness within a range of 0.002 inches to 0.02 inches after application;
• and
• lowering the coiled tubing string into the wellbore to the fully deployed state such that the coating covers an entirety of the outer surface of the coiled tubing string in the horizontal section of the wellbore and all of the coiled tubing string in the vertical section of the wellbore, but the coiled tubing string in the curved section of the wellbore does not have the coating.