A coupler member for coupling together the casings of two gas-insulated electrical elements

The invention relates to a coupler member for coupling together first and second gas-insulated electrical elements, respectively including a first casing and a second casing, in order to connect these casings to each other, said member including a socket (8) fitted with fastener means for fastening to the first casing and a sleeve (9) fitted with fastener means for fastening to the second casing. The sleeve (9) is engaged in the socket (8) having its free end presenting a groove (17) receiving a sealing gasket (16). The groove (17) is defined by a plane end wall (19) and by a flank (20) forming a surface of revolution. The free end of the socket (8) is fitted with a plate (18) in the form of a ring having clamping screws (22) that are screwed into the free end of the socket (8) in order to close the groove (17) and to compress the gasket (16) so that it deploys radially while bearing against the flank (20) and against the sleeve (9).