Abstract: A method of forming a grate plate for installation as part of a grate assembly in which free flowing abrasive material is supported for movement along a path while treatment gas flows upwardly through such material. The grate plate includes a relatively thin carrier plate modified to present a highly wear resistant upper surface, the carrier plate having slots formed therein through which treatment gas flows for passage through the material. The method is one which is economical even though the carrier plate itself is formed from relatively expensive material.

Abstract: A grate plate construction for installation as part of a grate assembly in which free flowing material is supported for movement along a path while treatment gas flows upwardly through such material. The construction has a relatively thin carrier plate having a highly wear resistant upper surface mounted in a supporting frame having ribs and webs which form with the carrier plate channels through which treatment gas flows for passage through the material via slots formed in the carrier plate by a high-energy process. The construction is economical even though the carrier plate itself is formed from relatively expensive material.

Abstract: This invention relates to a roller mill in which the shafts of the grinding rollers are mounted in two self-aligning roller bearings of which one forms a fixed bearing and the other is constructed as a vertically movable floating bearing. Such a roller mill is distinguished by a standard design which is economical to produce and can be equipped with a variable number of grinding rollers.

Abstract: The invention relates to a sifter in which the spiral for delivery of the air for sifting is divided into a plurality of channels lying one above another in which elements for setting the quantity of sifting air delivered to the individual channels are provided. In such a sifter the quantity of sifting air in the individual regions of the sifting chamber can be optimally adapted to the requirements, which leads to a substantial improvement in the degree of separation.

Abstract: The invention relates to an air separator having a rotor provided with feed passages for the material to be separated which extend radially outward and between which extraction openings are arranged. The space between adjacent feed passages which exists between the outer end of the feed passages and the extraction openings is axially delimited on at least one side by a stationary element forming part of an extraction housing. In this way, problems of wear in the outer region of the rotor are reduced. In addition, there is no longer any need for an exact sealing gap to be maintained between the rotor and the extraction housing. Finally, the free flow cross-section for the separation air is increased for the same overall dimensions of the separator.