A shut-off valve, comprising the following features: 1.1 a housing which encloses a flow opening for a medium; 1.2 a valve plate which can be twisted about a hinge pin between a closed position blocking the flow opening and an open position, said hinge pin extending transversely to the direction of flow; 1.3 two bearing pins (3, 4), each of which is mounted in a housing borehole (1.1) and engages in a pocket hole (2.1) in the valve plate; 1.4 the individual bearing pin (3, 4) is surrounded at the entrance of the pocket hole (2.1) by a first sealing ring cage, comprising an O-ring (11.1) which rests on the reveal of the pocket hole (2.1), and an O-ring (11.2) which rests on the jacket surface of the bearing pin (3, 4); 1.5 the bearing pin (3, 4) is surrounded at the radially inner end of the housing borehole (1.1) axially adjacent to the first sealing ring cage by a second sealing ring cage, comprising an O-ring (10.1) which rests on the reveal of the housing borehole (1.1), and an O-ring (10.2) which rests on the bearing pin (3, 4); 1.6 the pocket hole (2.1) in the valve plate and the housing borehole (1.1) are coated in the region of the sealing ring cages (10, 11); 1.7 a third sealing ring cage is provided in the region of the outer end of the housing borehole (1.1); 1.8 the bearing pin (3, 4) comprises at least one bearing bush; 1.9 the bearing bush is arranged between the third sealing ring cage and the second sealing ring cage; 1.10 the first sealing ring cage is rotationally fixed with the valve plate; 1.11 the second sealing ring cage is rotationally fixed with the housing; 1.12 an anticorrosion coating is respectively situated between the first sealing ring cage and the valve plate, and between the second sealing ring cage and the housing. 1.1 a housing which encloses a flow opening for a medium; 1.2 a valve plate which can be twisted about a hinge pin between a closed position blocking the flow opening and an open position, said hinge pin extending transversely to the direction of flow; 1.3 two bearing pins (3, 4), each of which is mounted in a housing borehole (1.1) and engages in a pocket hole (2.1) in the valve plate; 1.4 the individual bearing pin (3, 4) is surrounded at the entrance of the pocket hole (2.1) by a first sealing ring cage, comprising an O-ring (11.1) which rests on the reveal of the pocket hole (2.1), and an O-ring (11.2) which rests on the jacket surface of the bearing pin (3, 4); 1.5 the bearing pin (3, 4) is surrounded at the radially inner end of the housing borehole (1.1) axially adjacent to the first sealing ring cage by a second sealing ring cage, comprising an O-ring (10.1) which rests on the reveal of the housing borehole (1.1), and an O-ring (10.2) which rests on the bearing pin (3, 4); 1.6 the pocket hole (2.1) in the valve plate and the housing borehole (1.1) are coated in the region of the sealing ring cages (10, 11); 1.7 a third sealing ring cage is provided in the region of the outer end of the housing borehole (1.1); 1.8 the bearing pin (3, 4) comprises at least one bearing bush; 1.9 the bearing bush is arranged between the third sealing ring cage and the second sealing ring cage; 1.10 the first sealing ring cage is rotationally fixed with the valve plate; 1.11 the second sealing ring cage is rotationally fixed with the housing; 1.12 an anticorrosion coating is respectively situated between the first sealing ring cage and the valve plate, and between the second sealing ring cage and the housing.