A tube coupling system serves for providing annular flow through a flexible annular double lumen tube (3) between fluid reservoir(s) and flexible connection pieces (56,57) of an annular double lumen device (2). The tube coupling system has a first coupling component (4) and a second coupling component (6) and an end fitting system. The first coupling component (4) that has a female coupling part (11) and a male coupling part (12) adapted for coupling to a proximal end (5) of the flexible annular double lumen tube (3). The second coupling component (4) has a second interior pipe (31) that axially extends inside a second exterior pipe (32), a first end fitting (33) adapted for coupling to at least the female coupling part (11) of the first coupling component (4), and a second end fitting (34) adapted for coupling to any of the flexible annular double lumen tube (3) or the flexible connection pieces (56,57) of an annular double lumen device (2).