Rf antenna assembly with spacer and sheath and related methods

A radio frequency (RF) antenna assembly configured to be positioned within a wellbore in a subterranean formation for hydrocarbon resource recovery, the RF antenna assembly comprising:

• first and second tubular conductors to be positioned within the wellbore, and having adjacent joined together ends;
• first and second RF transmission line segments extending within said first and second tubular conductors and having adjacent joined together ends aligned with the joined together adjacent ends of said first and second tubular conductors;
• a dielectric tubular sheath surrounding said first RF transmission line segment and having a threaded outer surface;
• and
• a dielectric spacer threadingly received on the threaded outer surface of said dielectric tubular sheath and extending between said tubular sheath and adjacent portions of said first tubular conductor, said spacer having a plurality of spaced apart passageways therein for permitting fluid flow therethrough.

A method of making a radio frequency (RF) antenna assembly to be positioned within a wellbore in a subterranean formation for hydrocarbon resource recovery, the method comprising:

• positioning a first tubular conductor and a first RF transmission line segment within the wellbore, the first RF transmission line segment being within the first tubular conductor and having an end extending outward from the wellbore and past an end of the first tubular conductor;
• engaging a spacer onto an outer surface of a tubular sheath surrounding the first RF transmission line segment so that the spacer extends between the tubular sheath and adjacent portions of the first tubular conductor;
• threadingly engaging an end of a second RF transmission line segment, exposed from an end of a second tubular conductor, onto the end of the first RF transmission line segment extending past the end of the first tubular conductor;
• and
• sliding the second tubular conductor down the second RF transmission line segment and threadingly engaging the second tubular conductor onto the first tubular conductor.