Patent ID: 8660229

Claim:
A nuclear reactor primary coolant system ( 10 ), comprising: a primary coolant pipe ( 30 ) which delimits an inner space ( 32 ) in which a primary cooling fluid of the nuclear reactor flows, the primary cooling fluid flowing from the upstream direction in a downstream direction of the primary coolant pipe ( 30 ), and the primary coolant pipe has a central axis substantially parallel to the primary cooling fluid flow direction; an additional pipe ( 26 ) which is tapped from the primary coolant pipe ( 30 ), the additional pipe ( 26 ) delimiting an inner space which communicates with the inner space ( 32 ) of the primary coolant pipe ( 30 ); a sleeve ( 36 ) which has a first end ( 50 ) which is connected to the additional pipe ( 26 ), and a second free end ( 52 ) which is located in the inner space ( 32 ) of the primary coolant pipe ( 30 ), the second end of the sleeve opening up toward said central axis; wherein the second end ( 52 ) of the sleeve ( 36 ) terminates in and is delimited by a free peripheral edge ( 53 ) which has at least upstream and downstream sectors ( 56 , 58 ) which are directed in the upstream and downstream direction of the primary coolant pipe ( 30 ), respectively, the upstream sector ( 56 ) penetrating more deeply into the inner space ( 32 ) from the primary coolant pipe ( 30 ) than the downstream sector ( 58 ).