Turbocharger waste-gate valve

The device (10) has a lever (12) connected with a mechanical control device. A valve body (18) is provided with a flap portion (20), which covers a bypass aperture. The lever and the valve body are formed in one-piece and made of corrosion resistant nickel-base alloy and austenitic stainless steel i.e. HK 30 steel. The valve body is aligned to the bypass aperture to a limited extent by a clearance between the lever and a sleeve (14) during sealing the aperture of turbine housing of a turbo supercharger in a closed position of the flap device.