SU1248655A1 - Centrifugal impact mill - Google Patents

Description

The invention relates to the technique of grinding loose materials and can be used, for example, in the manufacture of building materials.

The purpose of the invention is to reduce the wear rate.

Fig. 1 shows a centrifugal impact mill; in Fig.2 a section in Fig.1; FIGS. 3 and 4 show a cut into fnig.1 (with two variants of the channel wall profile),

The centrifugal impact mill consists of loading and unloading funnels 1 and 2, housing 3, inside of which is mounted a rotor 4 with vents rotated towards the center of the canal rotor. impact plates made of hard alloy 7. To the rotor rigidly attached fender plates 8, which are located under the ANGLE 1-10 ° relative to the vertical axis of the mill at the exit points of the material accelerated by the rotor. The rotor 4 is mounted on a vertical shaft 9, which is rotated through a V-belt transmission 10 by an electric motor 11.

The mill operates as follows: ipasoM.

The source material is fed through the feed hopper 1 to the rotor 4, the material is accelerated by centrifugal force through 3 channels 5 expanding towards the center of the rotor. Using the channels 5 and 4 towards the center of the rotor 5 increases the concentration of the material flow The number of increase in the velocity of the particles of material along channel 5, with the greatest concentration being formed in the region where the material exits from channel 5, i.e. where the speed of the material and at the same time the wearing effect of the particles is maximum. By inducing concentration of the material flow through channel 5 leads to a decrease in wear rate. When used in

40

50

where K a

wear rate, coefficient proportional to THj

go - exponent, which is in the range of 2-2.5 V - particle collision speed

with the surface.

Thus, the intensity of the nose in the peripheral section of the channels is much higher than the intensity of wear near the center of the rotor.

The increase in the concentration of the material passing through the channel can lead to a decrease in the wear rate of about 10 times. With the use of channels narrowed to the periphery of the rotor, the concentration of the material to be passed in

as an abrasive material, quar - the peripheral portion of the channels. The sand with concentration of DD from the constancy of the output of the elements accelerated by the ro-ti along the entire length of the channel, yi ienb-in-shu area of the narrowed channel is achieved through the material monitor, worn out the intensity of wear 1 to 10 times

The material moving in the channels is additionally concentrated in the channel by means of TorOj that the walls of the channels are made profiled, while the optimal ratio of the radius of curvature of the channel R to the height of the channel h is R (1-2) h (Fig. 3). When making the walls of the channels by profiling with two planes, the optimum angle between the intersected planes is in the range of 60-150 °.

The particles ejected from the channel are crushed on the crushing plates 8, set at an angle of 1-10 ° relative to the vertical axis of the mill. On the surface of the 4 crushing plates 8 mounted together with the rotor, a protective layer of crushable material maintained by centrifugal forces is created, which leads to a sharp decrease in the wear of the crushing plates 8. Ground material

discharged from the mill through the funnel 2.

The speed of the particle when moving along the channel is directly dependent on the distance from the center, and the wear rate in the flow of abrasive particles is in the exponential dependence on the speed of the particles.

where K a

wear rate, coefficient proportional to THj

go is an exponent that ranges from 2-2.5; V - particle collision velocity

with the surface.

Thus, the intensity of wear in the peripheral section of the channels is much higher than the intensity of wear near the center of the rotor.

The increase in the concentration of the material passing through the channel can lead to a decrease in the wear rate of about 10 times. With the use of channels narrowed to the periphery of the rotor, the concentration of the material to be passed in

There is an increase in the amount of material per unit of time compared with the cross section of the initial part of the channel.

Profiling the walls of the channels with a radius R (1-2) h or two intersecting planes at an angle of 6i 60-150 ° contributes to an additional concentration of material in the channel section at the intersection of the horizontal plane of symmetry of channel 5 with the channel wall. The concentration occurs due to the efforts that occur on the profiled walls of the channel and tend to push the material along the walls of the lower and upper parts of the channel towards each other.

It has been established that at a radius of curvature or at an intersection angle of the planes with 150 °, the concentration of the material decreases, and the wear rate increases. For example, with a radius of curvature, the wear rate at an equal channel cross section and productivity exceeds the wear rate at 50%. The use of channels with profiled walls with a radius of R 1 h leads to undesirable. change in the wall configuration, which necessitates the installation of an additional transitional part of the wall. This has a negative effect.

on the wear resistance of the channel. The configuration of the channel walls by the intersection of two planes at an angle of 60 ° entails an excessive increase in the dimensions of the channel in the horizontal plane while maintaining this channel section size.

The inclination of the crushing plates relative to the axis ensures that the crushed material is reflected after hitting the crushing plates from the bottom without hitting it on the rotor. But to form at the same time a protective layer on the plates of comminuted material so that

reduce their wear, this slope should be 1-10 °.

sr1 / g.2

6-6

(pf / g.J

fizl

Editor I. Shulla

Compiled by L. Chubukova

Tehred M. Khodanich Proofreader M. Maksimishinets

Order 4158/6 Circulation 582 Subscription VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

Claims (2)

1. CENTRIFUGAL-SHOCK MILL, comprising a housing, inside of which a rotor with accelerating elements in the form of channels expanding towards the center of the channel is mounted on a vertical shaft, and crushing plates, characterized in that, in order to reduce the wear rate, the channels are made with a side wall profile in the form parts of a circle with a radius equal to one to two channel heights, or formed by two straight lines intersecting at an angle of 60-150 °. 2. The mill according to claim 1, characterized in that the crushing plates are attached to the rotor with an inclination relative to the vertical axis of 1-10 °. -1248655