SU1445781A1 - Tumbling barrel - Google Patents

Abstract

The invention relates to the construction of drum mills and can be applied in the mining, chemical, and construction industries. The goal is to increase the efficiency of the mill by using the centrifugal force of the inertia to accelerate the flow of pulp from the cavity of the mill and return large particles of material to the grinding chamber. The drum mill has a stationary cylindrical casing 12 located around the discharge chamber 8. The shell of the discharge chamber 8 and the lifters 7 have perforations, for example, in the form of slots. 1 hp ff. 3 il. (L 4 4i joint venture h 00 Fig-1

Description

The invention relates to grinding equipment and can be applied in the mining, chemical and construction industries of the industry in grinding ore and non-metallic minerals.

The purpose of the invention is to increase the efficiency of operation by using centrifugal inertia to accelerate the flow of pulp from the mill cavity and return large particles of material to the grinding chamber.

FIG. 1 shows a drum mill, a longitudinal section; FIG. 2 is a section A-A in FIG. one; FIG. 3 is a graph showing the dependences of the specific productivity of the mill on the finished class q on the ratio of the width of the lattice slits and the width of the slits in the shell of the mill b,

EG

The drum mill consists of grinding chamber 1, hollow trunnions 2 and 3, main bearings 4 and 5, discharge grid 6, perforated lifters 7, perforated shell of discharge chamber 8 with holes 9, return device, wavy in the form of a hollow cone 10, directed by a taper inside the stranded (Kitsa and connected with its large diameter with a hollow pin 3. On the surface of the hollow cone along the pattern there are recesses 11 of grooved shape.

In this case, the width of the grooves on the surface of the cone is 5–6 times greater than the width of the slits of the lattice. The cylindrical casing 12J located around the discharge chamber 8 is rigidly connected with its face cap 13 to the fixed part of the main bearing 5. At the bottom of the casing there is an opening 14 for draining the liquid pulp.

Drum mill works as follows

When the grinding chamber body 1 rotates, the material in it is crushed and under the action of the hydraulic differential of the pulpy and dynamic head moves through the discharge grate 6 to the lower part of the chamber 8. Then under the action of the total force of gravity and centrifugal force of inertia of rotation

Q

50

n j

SP

35

five

In the material, the pulp rapidly flows through the slits 9 in the shell of the discharge chamber 8 and the lifters 7, while a larger fraction is retained inside it. The slots of the cylindrical shell are 3-4 times smaller than the slots of the discharge grid 6, which makes it possible to separate large pieces of the critical class from the liquid pulp containing the largest amount of the finished class. This ratio is shown in the graph (Fig. 3), which shows the dependence of the specific productivity q of the mill in the finished class on the ratio of the width of the slits of the lattice to the width of the slits in the shell of the discharge chamber b.

Large particles are lifted by perforated lifters 7 into the upper part of the discharge chamber 8. The rotational speed of the mill is chosen such that in the upper part of the shell, the gravity forces acting on the particles are greater than the centrifugal inertia forces. The particles fall from the lifters 7 onto the grooves 11 and, slipping along the surfaces of the grooves, are returned to the mill for regrinding.

The angle between the core of the hollow cone 10 and the plane perpendicular to the axis of rotation should be 40-50. This is due to the fact that to glide the ore mass on the inclined surface of the trench, it is necessary that the friction coefficient f tgoi6bin be at least a critical value of 0.3. In this case, most of the undersized ore, slippery along the chute, is returned to the mill for regrinding. A small part of the ore falls out of the chute when the cone is rotated together

with a mill. Due to the fact that the width of the groove is 5-6 times greater than the width of the slits of the lattice, large particles of rock do not get stuck in the groove, but freely slide inside the chamber because of. shallow Finally, all the uncrushed ore is returned to the mill For regrinding. And the pulp containing the largest amount of finely ground finished class flows intensively through the slots 9. Accelerated unloading is provided due to the total effect of centrifugal inertia forces of the rotating material and gravity in the lower part of the shell 8. Leaked through the slots 9, the pulp falls on the inner surface of the stationary cylindrical

the casing 12, through which it flows down and is discharged through the opening 14

The drum mill makes it possible to increase the efficiency of the mills due to the accelerated outflow of pulps from the mill cavity under the action of summation of gravity and the centrifugal inertia force of the rotating material. The specific productivity of the finished class is expected to increase by 10-12%,

In addition, large pieces are prevented from entering the pulp, which in the base object leads to the need to install butars on the discharge pivot to protect adjacent processing equipment. When the mill operates in a closed cycle with a classifier, the circulation of a critical class is excluded, which reduces the energy consumption and prevents increased wear of the parts of the classifier and the combined feeder of the mill.

Claims (2)

1. Drum mill, containing grinding chamber, unloading a chamber with a diameter larger than the diameter of the grinding chamber, lifters, hollow trunnions, a discharge grid, a conical shell connecting the grinding chamber and a discharge chamber, a discharge cone differing in efficiency of the mill due to the use of centrifugal inertial force to accelerate the outflow of pools from the cavity of the mill and return large particles of material to the chamber, grinding, the mill is equipped with a stationary cylindrical casing located around the discharge chamber, and the shell of the discharge chamber and lifters are perforated, the discharge cone is directed by its the smaller diameter inside the mill and on its surface along the generatrix are hollow grooved. 2. Mill pop. 1, which differs from the fact that the perforation of the shell of the discharge chamber and lifters is made in the form of slots located along the radius of the shell, and their width is 3-4 times less than the width of the lattice slots and the plane of the perpendicular axis of the plane is 40-50. and. g fn / ii Fig.d five . 8tl8z