Manufacturing methods for dual concentric tubing

A method of performing artificial lift of fluid produced from an underground formation in a wellbore, the method comprising:

• providing an outer pipe;
• providing an inner pipe having a bore;
• placing the inner pipe in the bore of the outer pipe, such that an annulus is formed between an inner surface of the outer pipe and an outer surface of the inner pipe;
• forming a joint pipe element by connecting the inner pipe to the outer pipe with a connecting mechanism so that a rotational torque can be transferred from the outer pipe to the inner pipe;
• connecting a plurality of joint pipe elements to form a tubing system;
• lowering the tubing system into the wellbore;
• and
• pumping a pressurized gas through the tubing system to lift the fluid from the underground formation to the surface.