The invention refers to a drainage system (100), in particular a roof drainage system, comprising an outlet member (10) and a flow restrictor (20), whereby the flow restrictor (20) is situated above the outlet member (10). The flow restrictor (20) comprises a contact portion (22) and the outlet member (10) comprises a flange portion (12), whereby a first sealing member (30) is arranged on and/or along the flange portion (12) of the outlet member (10) and a second sealing member (40) is arranged at the contact portion (22) of the flow restrictor (20).

The invention relates to a sealing ring including, axially, a main portion (2) and a secondary portion (3), connected by a weakened intermediate portion (4) which can be broken under an axial force applied between the main portion and the secondary portion, the main portion (2) including an annular sealing sleeve (5) and a projecting outer shoulder (6) arranged at the end of the annular sealing sleeve (5), opposite the breakable portion (4), and the secondary portion (3) including a projecting inner shoulder (10). Said annular sleeve (5) of the main portion (2) of the ring can be inserted between ducts (16, 17) that are inserted into one another, said projecting outer shoulder (6) of the main portion (2) abutting against the end of the outer duct surrounding the inner duct, and said projecting inner shoulder (10) of the secondary portion (3) abutting against the end of the outer tube that is inserted into the outer duct.

The invention relates to a sealing ring including, axially, a main portion (2) and a secondary portion (3), connected by a weakened intermediate portion (4) which can be broken under an axial force applied between the main portion and the secondary portion, the main portion (2) including an annular sealing sleeve (5) and a projecting outer shoulder (6) arranged at the end of the annular sealing sleeve (5), opposite the breakable portion (4), and the secondary portion (3) including a projecting inner shoulder (10). Said annular sleeve (5) of the main portion (2) of the ring can be inserted between ducts (16, 17) that are inserted into one another, said projecting outer shoulder (6) of the main portion (2) abutting against the end of the outer duct surrounding the inner duct, and said projecting inner shoulder (10) of the secondary portion (3) abutting against the end of the outer tube that is inserted into the outer duct.

The invention refers to a drainage system (100), in particular a roof drainage system, comprising an outlet member (10) and a flow restrictor (20), whereby the flow restrictor (20) is situated above the outlet member (10). The flow restrictor (20) comprises a contact portion (22) and the outlet member (10) comprises a flange portion (12), whereby a first sealing member (30) is arranged on and/or along the flange portion (12) of the outlet member (10) and a second sealing member (40) is arranged at the contact portion (22) of the flow restrictor (20).