RU2674617C1 - Centrifugal mill - Google Patents

Abstract

FIELD: disintegrators and crushing devices.

SUBSTANCE: invention relates to the various materials crushing devices and may be used in production of construction materials and other industries. Mill contains two housings 1, located in the same plane and interconnected by tangential channel 2. Side walls of tangential channel 2 converge in the plane of symmetry of a centrifugal mill at an angle of 120–150°. Each housing 1 has rotor 3 which is rotatable in the direction of the corresponding outlet of the channel, on which acceleration vanes 4 are fixed. In tangential channel 2 there is discharge branch pipe 5 equidistant from the axis of rotation of rotors 3. Feed nozzles 6 in each housing 1 for supplying the material to be ground are arranged on an arc of a circle of 50…280°, counting from the straight line passing through the centers of rotation of rotors 3 and a radius equal to 1/4…3/4 of the radius of rotor 3 with the center on the vertical axis of the latter. At the lower end of each loading nozzle 6 there is an inclined cut at an angle of 45° on the side opposite to the rotation of corresponding rotor 3. Each accelerating blade 4 has a cut corresponding to the profile of loading nozzle 6 with the provision of technological gap. Extreme starting point of each accelerating blade 4 is adjoined by straight-line limiter 7 fixed on a segment connecting the extreme starting point of accelerating blade 4 with the extreme final point of subsequent accelerating blade 4 in the direction of rotation of rotor 3. Minimum distance between the extreme end point of rectilinear limiter 7 and subsequent accelerating blade 4 is greater than 2 D_max, where D_max – maximum particle size of the material to be ground.

EFFECT: mill is characterized by more efficient grinding of the material.

1 cl, 4 dwg

Description

The invention relates to devices for grinding various materials and can be used in the production of building materials, as well as in other industries.

A known design of a centrifugal mill containing a stepped housing, each subsequent step in which, counting along the movement of the material, is made of a larger diameter, a stepped rotor with beams horizontally located in the housing, a loading and unloading pipe (USSR Author's Certificate for the Invention No. 671839, V02C 13 / 14, publ. 05.07.1979, bull. No. 25).

Also known is a centrifugal mill of selective grinding, containing a housing with a loading nozzle on its cover and an unloading nozzle, as well as a rotor with accelerating vanes installed in it (USSR Author's Certificate for the Invention No. 952321, В02С 7/08, publ. 1975, bull. No. 31 )

The disadvantages of the known designs is the low efficiency of the grinding process and low fineness of grinding.

The closest technical solution to the proposed one is a centrifugal mill (RF Patent for the invention No. 2567522, В02С 13/26, published on November 10, 2015, bull. No. 31), containing two bodies placed in one plane and interconnected by a tangential channel, common for both cases, in each case there is a rotor arranged to rotate in the direction of the corresponding channel outlet, on which the accelerating blades are fixed, in the tangential channel there is an unloading nozzle equidistant from the rotational axes c, the loading nozzles in each housing for feeding the material to be ground are located on an arc of a circle equal to 50 ... 280 °, counting from a straight line passing through the centers of rotation of the rotors and a radius equal to 1/4 ... 3/4 of the radius of the rotor centered on the vertical axis of the latter , at the lower end of each loading nozzle there is an inclined cut at an angle of 45 ° from the side opposite to the rotation of the corresponding rotor, each accelerating blade has a cutout corresponding to the profile of the loading nozzle providing technological clearance, side the walls of the tangential channel converge in the plane of symmetry of the mill, the angle between the converging walls is 120-150 °.

With the essential features of the claimed invention the following set of features of the prototype coincides: two buildings placed in the same plane and connected by a tangential channel. In each housing there is a rotor arranged to rotate in the direction of the corresponding channel outlet, on which the accelerating blades are fixed. In the tangential channel there is an unloading pipe equidistant from the axis of rotation of the rotors. The loading nozzles in each housing for feeding the material to be ground are located on an arc of a circle equal to 50 ... 280 °, counting from a straight line passing through the centers of rotation of the rotors and a radius equal to 1/4 ... 3/4 of the radius of the rotor centered on the vertical axis of the latter. At the lower end of each loading nozzle there is an inclined cut at an angle of 45 ° from the side opposite to the rotation of the corresponding rotor. Each accelerating blade has a cutout corresponding to the profile of the loading pipe with technological clearance. The side walls of the tangential channel converge in the plane of symmetry of the mill. The angle between the converging walls is 120-150 °.

Despite the fact that in this design the relative speed of movement of the crushed material is more than 300 m / s, there is a low grinding efficiency of the material in the tangential channel. This is due to the low density of the oncoming flows of particles of the crushed material coming off the rotors. The insufficient density of oncoming flows of particles coming off the rotors is associated with an increased width of their divergence in the tangential channel, which reduces the grinding efficiency.

The objective of the invention is to increase the efficiency of the grinding process by reducing the width of the divergence of the particle flows of the crushed material in the tangential channel.

This is achieved by the fact that the centrifugal mill contains two housings located in the same plane and connected by a tangential channel, the side walls of which converge in the plane of symmetry of the mill at an angle of 120-150 °. In each housing there is a rotor arranged to rotate in the direction of the corresponding channel outlet, on which the accelerating blades are fixed. In the tangential channel there is an unloading pipe equidistant from the axis of rotation of the rotors. The loading nozzles in each housing for feeding the material to be ground are located on an arc of a circle equal to 50 ... 280 °, counting from a straight line passing through the centers of rotation of the rotors and a radius equal to 1/4 ... 3/4 of the radius of the rotor centered on the vertical axis of the latter. At the lower end of each loading nozzle there is an inclined cut at an angle of 45 ° from the side opposite to the rotation of the corresponding rotor. Each accelerating blade has a cutout corresponding to the profile of the loading pipe with technological clearance. In the proposed solution, a rectilinear limiter is attached to the extreme starting point of each accelerating vane, mounted on a segment connecting the extreme starting point of the accelerating vane with the extreme end point of the subsequent accelerating vane in the direction of rotation of the rotor. The minimum distance between the extreme end point rectilinear limiter and subsequent booster spatula over 2 D _max, wherein D _max - the maximum size of the grinding material particles.

The invention is illustrated in the drawing, where in FIG. 1 shows a cross section BB in FIG. 2 (centrifugal mill); in FIG. 2 is a section AA in FIG. 1 (longitudinal section of a centrifugal mill); in FIG. 3 is a section BB of FIG. 1 (loading branch pipe); in FIG. 4 is a view D in FIG. 3.

The centrifugal mill contains two housings 1 located in the same plane and connected by a tangential channel 2, common to both buildings 1. The side walls of the tangential channel 2 converge in the plane of symmetry of the mill. The angle between the converging walls is 120-150 °.

In each housing 1 there is a rotor 3 rotatably rotatable in the direction of the corresponding channel outlet on which the accelerating vanes 4 are fixed. In the tangential channel 2 there is an unloading nozzle 5 equidistant from the rotational axes of the rotors 3. The loading nozzles 6 in each housing 1 for feeding the crushed material is located on an arc of a circle equal to 50 ... 280 °, counting from a straight line passing through the centers of rotation of the rotors 3 and a radius equal to 1/4 ... 3/4 of the radius of the rotor 3 centered on the vertical axis of the latter. Each accelerating blade 4 has a cutout corresponding to the profile of the loading pipe 6 with a technological gap. At the lower end of each loading nozzle 6 there is an oblique cut at an angle of 45 ° from the side opposite to the rotation of the corresponding rotor 3. A rectilinear limiter 7 is attached to the extreme starting point of each accelerating vane 4, mounted on a segment connecting the extreme starting point of the accelerating vane 4 with the extreme end the point of the subsequent accelerating vane 4 in the direction of rotation of the rotor 3. The minimum distance between the extreme end point of the rectilinear limiter 7 and the subsequent accelerating vane 4 is greater than 2 D _{ma x} , where D _max - the maximum particle size of the crushed material.

Between the output end of each rotor 3 and the inner surface of the housing 1 there is a technological gap that ensures rotation of the rotor 3.

Centrifugal mill operates as follows.

The crushed material, for example limestone, is simultaneously fed through the loading nozzles 6 to the accelerating blades 4 of both rotors 3. Due to the fact that the loading nozzles 6 are displaced relative to the rotational axes of the rotors 3, only one of the accelerating vanes 4 is crushed at each time interval. depending on the properties and size of the crushed material, the location of the loading nozzles 6 on an arc of a circle equal to 50 ... 280 °, counting from a straight line passing through the centers of rotation of the rotors 3, and a radius equal to 1/4 ... 3/4 for ca rotor 3 with its center on the vertical axis of the latter.

Particles of the crushed material fall on the accelerating blades 4 and accumulate on them. The following particles begin to slide along the accumulated material and, due to centrifugal force from the accelerating vanes 4, are sent to the tangential channel 2. Particles of material moving in the spaces between the accelerating vanes 4 collide with the surface of the rectilinear limiter 7 and are directed to the surface of the accelerating vanes 4, which provides a common the coordinate separation of particles from the accelerating blades 4 for each rotor 3.

The speed of the particles directed towards each other from the bodies 1 into the tangential channel 2 exceeds the rate of destruction of the material particles, resulting in their effective grinding. Particles of crushed material from the tangential channel 2 are sent to the discharge pipe 5.

The presence of rectilinear limiters located on the segment connecting the extreme starting point of the accelerating blade with the extreme end point of the subsequent accelerating blade in the direction of rotation of the rotor in combination with the other elements, reduces the width of the divergence of the oncoming flows of particles of the crushed material in the tangential channel, thereby increasing the density of these flows particles, which increases the efficiency of the grinding process.

Claims (1)

A centrifugal mill containing two housings located in the same plane and connected by a tangential channel, the side walls of which converge in the plane of symmetry of the mill at an angle of 120-150 °, in each case there is a rotor rotatable in the direction of the corresponding channel outlet, on which booster blades are fixed, in the tangential channel there is an unloading nozzle equidistant from the axes of rotation of the rotors, loading nozzles in each casing for feeding the ground mate the rials are located on an arc of a circle equal to 50-280 °, counting from a straight line passing through the centers of rotation of the rotors and a radius equal to 1 / 4-3 / 4 of the radius of the rotor centered on the vertical axis of the latter, at the lower end of each loading nozzle there is an inclined cut at an angle of 45 ° from the side opposite to the rotation of the corresponding rotor, each accelerating blade has a cutout corresponding to the profile of the loading nozzle with technological clearance, characterized in that to the extreme starting point of each accelerating blade is adjacent there is a rectilinear limiter mounted on a segment connecting the extreme starting point of the accelerating blade with the extreme end point of the subsequent accelerating blade in the direction of rotation of the rotor, while the minimum distance between the extreme end point of the linear limiter and the subsequent accelerating blade is more than 2 D _max , where D _max is the maximum particle size of the crushed material.

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