Abstract: Solid particulate material such as cement raw material, clinker, etc., is finely ground, crushed or pulverized, by means of a rotatable generally vertically oriented container of generally inverted frusto-conical shape, and having grinding media such as steel balls disposed therein. The discrete particles of the material to be pulverized are fed into the upper part of the container as it is rotated about a central vertical axis, and egress of the resulting finely ground material by centrifugal force from the container to external collection is accomplished by the provision of slits in the inclined side wall of the rotary container. A fixed cover enclosing the upper part of the container is provided with inner guide vanes which are typically curved or of a vortical form. A preliminary coarse crushing mechanism may be provided, and this mechanism may be integrated with the rotary container, so that coarse crushing and fine crushing may be performed by a single device.

Abstract: A roller mill having a grinding plate revolving around a vertical central axis and a plurality of grinding rollers arranged in grinding rolling contact with the grinding plate is constructed with a separate frame supporting each of the grinding rollers for rotation about a stationary axis, with each frame having projections at both its ends constructed to form a connecting joint between the frames at each of the ends thereof.

Abstract: The present invention relates to a vertical roller mill including a grinding roller which is urged against a grinding path on a grinding table by a hydraulic cylinder. The loading on the roller is measured by a transducer and the acceleration of the roller by an accelerometer. Resulting signals are combined at a controller which controls a valve through which hydraulic fluid is supplied to the hydraulic cylinder, so that the loading is compensated for the influence of the instantaneous velocity and acceleration of the roller.

Abstract: Disclosed is a vertical roller mill wherein a material fed to a casing is ground between a rotary table and a plurality of grinding rollers which are pressed against the rotary table and are rotated as the rotary table is rotated, the ground material being entrained by the upblast of heated gas or the like and discharged out of the casing. A bracket extended above the rotary table for carrying the grinding roller is pivoted at the side of the casing, and a pull-down means is connected with the bracket adjacent to the part thereof at which the grinding roller is supported. The bracket is pulled down by the pull-down means so that the grinding roller may be pressed against the rotary table.

Abstract: A bowl mill pulverizer includes a mill housing supported on and extending upwardly from a foundation. A milling bowl is supported within the housing for rotation about a vertical axis. A frame is located over the bowl with arms extending downwardly from the frame and rotatably supporting grinding rolls positioned within the bowl. Upwardly extending pull rods are secured at their upper ends to the frame and at their lower ends to the foundation. The pull rods press the grinding rolls downwardly against the bowl. The pull rods are disposed at an angle to the vertical and slope outwardly and downwardly toward the foundation.

Abstract: A roll mill, more specially for coal, has a turning pan and a number of rolls running thereon for producing a milling effect. Each roll is supported on a rocker arm, able to be turned about a horizontal axis which is roughly tangential to the pan. The rocker arm and the roll on it are forced down against the pan by a hydraulic cylinder joined with a fork which, in turn, is joined with the rocker arm for turning it about the turnpin. The fork may be unjoined from the rocker arm for upkeep work on the roll. Each rocker arm has a gas-tight cover structure which is part of the casing of the mill.

Abstract: A method is disclosed for operating a roller mill of the type having a rotating grinding path upon which one or more grinding rollers are disposed for rotatably grinding the material to be ground. In particular, a method is disclosed for maintaining a constant predetermined thickness of the grinding cushion between the grinding roller or rollers and the grinding path. More particularly, according to the invention the mean grinding pressure increases within fixed limits when the mean thickness of the grinding cushion is larger than predetermined, and decreases when the mean thickness of the grinding cushion is smaller than predetermined. The invention also pertains to an improved roller mill of the type described, for practicing the inventive method.

Abstract: A vertical roller mill includes a grinding table positioned for rotation around a vertical axis and two upright grinding rollers resting on their peripheral grinding surfaces on the grinding table for grinding material thereon. Each of the grinding rollers is rotatably mounted on a respective fixed horizontal shaft connected at one end to a common, central frame and at the other end to a draw bar. Preferably, the draw bar is regulated by a hydraulic cylinder secured in a bracket which is anchored in the mill foundation.

Abstract: An electronic system particularly suited for effecting control over the pressure of the hydraulic fluid through which the journal loading is established on the grinding rolls (20) of a bowl mill (10) of the type that is employed to pulverize coal. The subject electronic system is operatively connected in circuit relation to the belt feeder means (12), located externally of the bowl mill (10), that supplies to the bowl mill (10) the coal that is to be pulverized therein. In addition, the subject electronic system is also operatively connected in circuit relation to the hydraulic power unit (22) of the bowl mill (10) that provides hydraulic fluid under pressure to the grinding rolls (20).

Abstract: The specification describes a roller mill comprising a rotary grinding pan and grinding rollers adapted to roll on this grinding pan and which are journalled stationarily though with a provision for vertical pivoting. In accordance with the invention the grinding pan is supported by a plurality of hydrostatic axial individual bearings, which are arranged substantially symmetrically with respect to the grinding pan and take up all vertical loads. There are also provided a plurality of hydrostatic radial bearings arranged substantially symmetrically around the periphery of the grinding pan to guide and take up radial forces on the grinding pan.

Abstract: A new and improved design of a pulverizer air throat for low-pressure drop, reduced erosion and improved flow distribution.

Abstract: An improved pulverizer roller loading arrangement applying compressive force directly to roller brackets and providing shear and pivoting means integrally connecting roller brackets to split corner roller support blocks.

Abstract: A roller mill of the sort with a pan turning about an upright axis, a driving system under the pan and rocking levers, pushing rollers against the pan, has a roller weighting system made up of a hydraulic cylinder, pulling the levers together, and joined with an air accumulator. The cylinder is turningly supported near its center of gravity in one of the levers.

Abstract: The specification describes a roller mill comprising a rotary grinding pan and grinding rollers adapted to roll on this grinding pan and which are journalled stationarily though with a provision for vertical pivoting. In accordance with the invention the grinding pan is supported by at least three hydrostatic axial individual bearings, which are arranged substantially symmetrically with respect to the grinding pan and can take up all vertical loads.

Abstract: Spring roll mill having stationary grinding rolls yieldingly pressed from within the mill toward a circumferential grinding ring mounted on a grinding dish and revolving together therewith, a central feed inlet for supplying to the mill from above material to be ground therein, and a discharge outlet for discharging the ground material from the mill together with an air flow, includes means for introducing the air flow from below into substantially the middle of the grinding dish.

Abstract: A bowl mill for pulverizing coal, wherein two bowl surfaces are rotated on the same shaft. The raw crushed coal is pulverized in one of the bowls, and the pulverized coal therefrom is then transported in an air stream to a classifier from where the fines are carried on to the ultimate point of use, and the more coarse particles are discharged into the second bowl for further grinding.