Abstract: A vertical ball mill includes: a rotor, which is axially and radially supported at an upper end; a stator, which radially extends around the rotor, stands in a self-supporting manner and has a lateral surface that is oriented tangentially to the rotor; and a base plate supporting the weight of the stator. The stator includes least two stator segments, which may be separated from one another, stand unsupported in the separated state and may be moved relative to one another; wherein each of the stator segments has, on at least one side edge of a wall which forms the lateral surface, a sealing surface for sealing to the other stator segment, and has, on the bottom edge, a standing surface for sealing to the base plate; wherein the stator segment standing surface weighs on a load-bearing surface of the base plate.

Abstract: A vertical ball mill includes: a rotor, which is axially and radially supported at an upper end; a stator, which radially extends around the rotor, stands in a self-supporting manner and has a lateral surface that is oriented tangentially to the rotor; and a base plate supporting the weight of the stator. The stator includes least two stator segments, which may be separated from one another, stand unsupported in the separated state and may be moved relative to one another; wherein each of the stator segments has, on at least one side edge of a wall which forms the lateral surface, a sealing surface for sealing to the other stator segment, and has, on the bottom edge, a standing surface for sealing to the base plate; wherein the stator segment standing surface weighs on a load-bearing surface of the base plate.

Abstract: A plurality of cylinder sections are welded together to form a milling cylinder, wherein, prior to welding, individual cylinder sections are machined in the region of their end edges to be welded, using at least one machining tool. Furthermore, the cylinder section to be machined is provided with inwardly oriented bracing means, wherein a temporary axle is fitted on the bracing means such that the temporary axle is oriented in the mid-axis of the cylinder section, and wherein the at least one machining tool is fastened to the temporary axle by means of a holder and the machining tool is rotated relative to the cylinder section about or with the temporary axle during the machining of the end edges.

Abstract: A plurality of cylinder sections are welded together to form a milling cylinder, wherein, prior to welding, individual cylinder sections are machined in the region of their end edges to be welded, using at least one machining tool. Furthermore, the cylinder section to be machined is provided with inwardly oriented bracing means, wherein a temporary axle is fitted on the bracing means such that the temporary axle is oriented in the mid-axis of the cylinder section, and wherein the at least one machining tool is fastened to the temporary axle by means of a holder and the machining tool is rotated relative to the cylinder section about or with the temporary axle during the machining of the end edges.

Abstract: The invention relates to a method for reconditioning a used grinding roller of a material bed roller mill having profile-members which are embedded, with a portion of the length thereof, in holes of the roller body and, with the remainder of the length thereof, project above the surface of the roller body. For the reconditioning operation, after the worn profile-members are removed, the worn surface of the roller body is turned, and a material layer is applied in a welding operation and is provided with holes for receiving new profile-members. Such a method allows particularly cost-effective reconditioning.

Abstract: The invention relates to a milling roller of a high-pressure material bed roller mill, having profile-members which are embedded with a portion of the length thereof in holes of the roller body and, with the remainder of the length thereof, protrude above the surface of the roller body, with, when the milling roller is new, the holes having different depths and the profile-members having different lengths in differently loaded part-regions of the width of the roller body. Such a construction brings about a long service-life for the roller and cost-effective reconditioning after operational wear with a production operation which reduces costs.

Abstract: The invention relates to a method for reconditioning a used grinding roller of a material bed roller mill having profile-members which are embedded, with a portion of the length thereof, in holes of the roller body and, with the remainder of the length thereof, project above the surface of the roller body. For the reconditioning operation, after the worn profile-members are removed, the worn surface of the roller body is turned, and a material layer is applied in a welding operation and is provided with holes for receiving new profile-members. Such a method allows particularly cost-effective reconditioning.

Abstract: The invention relates to a milling roller of a high-pressure material bed roller mill, having profile-members which are embedded with a portion of the length thereof in holes of the roller body and, with the remainder of the length thereof, protrude above the surface of the roller body, with, when the milling roller is new, the holes having different depths and the profile-members having different lengths in differently loaded part-regions of the width of the roller body. Such a construction brings about a long service-life for the roller and cost-effective reconditioning after operational wear with a production operation which reduces costs.

Abstract: The roller mill according to the invention has two rotatably supported, counter-rotating rollers which together form a roller gap. There is provided in each of the two rollers at least a first and a second region which have different diameters so that the roller mill has at least a portion having a smaller roller gap and at least a portion having a larger roller gap.

Abstract: The invention relates to a method for reconditioning a used grinding roll of a high-pressure bed grinding mill. In said method, the surface of the rolling body is turned by a certain degree after removing the worn profiled members, whereupon the existing bores can be deepened to a depth that is sufficient for receiving new profiled members or new bores can be created according to a new bore pattern. New profiled members are then inserted into the bores. The inventive method allows a used grinding roll to be reconditioned in a particularly time-saving manner while economizing material.

Abstract: The invention relates to a grinding roll with a basic roll body as well as a plurality of wear protection elements made from hard metal which form at least a part of the roll surface. The basic roll body has recesses extending in the circumferential direction, a plurality of wear protection elements being disposed one behind the other in the circumferential direction in each recess.

Abstract: The invention relates to a shaft preheater for preheating material in lump form with at least one shaft for receiving the material, a bridge disposed in the shaft for delivering hot gases which flow through the material from the bottom upwards, and a device for filling the shaft with the material such that the shaft is charged centrally thereby developing a filling cone. The bridge is disposed at an inclination corresponding to the filling cone in order to guarantee an even flow through the fill. The device for filling the shaft comprises a vertically adjustable feed chute.

Abstract: The invention relates to the reduction of fine ores, whereby in a multi-stage gas suspension preheater the fine ores are preheated, calcined and then reduced in at least one lowest heat exchanger stage with the addition of a reducing agent in a delivered hot gas stream. The principal part of the reducing heat treatment of the fine ores is carried out in a reactor loop constructed in the lowest heat exchanger stage of the gas suspension preheater. The reactor loop has an uptake conduit section and a curved section adjoining the uptake conduit section and with which the reactor loop opens into at least one precipitating cyclone which is disposed downstream and for this purpose a hot reducing gas is introduced into the rising hot gas stream.

Abstract: A shaft preheater to achieve an improved adaptation of layer height to particle size spectrum of material to be preheated. The shaft preheater includes a plurality of shafts for receiving lumpy material, an arrangement for filling the individual shafts with the lumpy material to be preheated and means for limiting the layer height in the shafts. The means for limiting the layer height include a needle valve and have an arrangement for coarse adjustment and an arrangement for fine adjustments.

Abstract: The invention relates to a shaft preheater for preheating material in lump form with at least one shaft for receiving the material as well as a bridge disposed in the shaft for delivering hot gases which flow through the material from the bottom upwards. The bridge is disposed at an inclination in order to guarantee an even flow through the fill.

Abstract: The invention relates to a grinding roll with a basic roll body as well as a plurality of wear protection elements made from hard metal which form at least a part of the roll surface. The basic roll body has recesses extending in the circumferential direction, a plurality of wear protection elements being disposed one behind the other in the circumferential direction in each recess.

Abstract: The invention relates to a shaft preheater with a plurality of shafts for receiving lumpy material, an arrangement for filling the individual shafts with the lumpy material to be preheated and also means for limiting the layer height in the shafts. The means for limiting the layer height have an arrangement for coarse adjustment and an arrangement for fine adjustment.

Abstract: The invention relates to a roll mill with two rolls which are rotatably mounted in a machine frame and have an outer wear protection casing. In order to facilitate a particularly simple and rapid replacement of the wear protection casings on the rolls, both rolls are mounted only at one end in the machine frame.

Abstract: In this method of comminution according to the invention, pre-comminuted ore material is subjected to material bed comminution in a material bed roll mill. In order to achieve optimal comminution even of very different ore materials with a high throughput the ore material is pre-comminuted in an autogenous mill, whereupon at least fractions of fine material are separated out of the pre-comminuted material before the rest of the material is further comminuted in the material bed comminution.

Abstract: The invention relates to a method as well as to apparatus for combined grinding of at least two materials of differing grindability, such as clinker and limestone, wherein the material which is more difficult to grind is pre-crushed to a Blaine fineness of grinding of at least 700 cm.sup.2 /g and there-after is further ground together with the other material to produce the finished material.