Abstract: An apparatus for separating castings from moulding sand is provided with a container revolving around the longitudinal horizontal or near horizontal axis. The side surface of the container is provided with suitable slots ensuring an inflow of air into this container. The slots are located at one or several points before a sieve wall located at the end of the container. The sieve wall is used for separation of the moulding sand from the castings. The side surface of such a container can be formed by a coaxial combination of cylindrical and/or conical drums of diameters increasing in steps toward the outlet opening of the container and thus forming annular slots. Air flow is initiated by a pressure difference inside and outside the container this being obtained by exhausting the dusted air and water vapor through casing of outlet opening and covering outlet opening.