Method for providing a circuit for biological liquid and circuit obtained

A method for providing a circuit for biological liquid comprising a plurality of connectors and a network for routing the liquid between said connectors, characterized in that it comprises: - the step of obtaining a bag (11; 111) comprising two flexible films (25 , 26; 125,126) secured to each other by a sealing element (27; 127) that delimits a closed contour, and open on the inside and outside of said contour, with said routing network connectors (40A-40E) and an inflation connector (41); - the step of obtaining a press (10; 10 '; 110) comprising two half-shells (13, 14; 13', 14; 113, 114) configured to cooperate with said bag (11; 111) in order to form, between said films (25, 26; 125, 126), by embracing said bag (11; 111) between said half-wraps (13, 14; 13 ', 14; 113, 114) and by injecting an inflation agent through said inflation connector (41), pipes (12; 112A-112F) of said routing network; in such a way that said bag (11; 111) and said press (10; 10 '; 110) are selected so that at least one of said pipes (12; 112A-112F) has a contour of which at least a part is delimited exclusively by cooperation with said press (10; 10 '; 110), said press being (10; 10'; 110) selected in such a way that said half shells (13, 14; 13 ', 14; 113, 114) each comprise a recessed channel (16, 18) for said at least one pipe (12; 112A-112F ), having a contour of which at least a part is delimited exclusively by cooperation with said press (10; 10 '; 110); and - the step of forming said pipes (12; 112A-112F) by clamping said bag (11; 111) between said half-shells (13, 14; 13 ', 14; 113, 114) and the injection of an inflation agent through said inflation connector (41).