SU659183A1 - Method of automatic control and regulation of filling of drum mill with milling and millable materials - Google Patents

Description

to increase the power of the extreme value, then compare the extreme value with the current value of the instantaneous value, calculate the difference signal and judge the wear of the lining of the mill and the grinding material.

The drawing shows a block diagram of the device. The circuit includes a meter 1 of instantaneous values of the power of a mill motor, a meter of 2 sinking walls of a drum mill, a radioisotope example, a computing device 3, controller 4, an element of us 5, an extreme controller 6, a summation unit 7.

The extreme power of the PM used by the mill motor drifts from the vertical and reaches its maximum value when the total occupation of the grinding and grinding materials changes in a relatively narrow range (/ o equals 42-45%). The kind of extreme characteristic (Io) depends on the amount of intramillary filling with a grinding material (balls) - the material being crushed (ore), as well as the condition of the drum lining (the degree of its grinding). With a change in ball filling, the characteristics move vertically, with a change in ore holding (for the case of a specific ball load) - horizontally, along extreme curves. Moreover, the left half (the pre-extremal region) of the characteristics corresponds to the "normal conditions of operation of the mill, the right to the overloaded ones. The extreme point of a certain curve corresponds to the most efficient mode of operation of the mill for given conditions of ball filling. Among the many power extremes (for various ball filling conditions), there is a mode in which the grinding process reaches its extreme value.

When considering the dependence of the readings of a radioactive meter on the degree of filling of the mill with grinding mass and ore, it follows that this relationship is expressed by a linear relationship and does not depend on the proportional composition of the intramill mass, its density, grain size and degree of wear of the lining, which significantly improves the quality of the monitored parameter compared to sound signal.

The device works as follows.

At the same time, the instantaneous values of the power of the mill motor are measured and its overall degree of filling.

using a radioactive meter 2. The received signals are sent to the computing device 3 and the correlation coefficient is determined between them. Depending on its size and sign, through regulator 4, the value of the initial feed of the ore supplied to the mill is affected and its zero value is achieved. When the value of the correlation coefficient reaches zero (which corresponds to the optimal conditions for filling the mill with ore for a given ball load), the memory element 5 is simultaneously affected and the maximum

the power value and through the extreme controller 6 for the ball loading into the mill, achieve the maximum power value (corresponding to the extreme conditions of the ball filling).

Over time, wear of the lining and displacement of the characteristic but power upwards occur. The extreme controller outputs the object to the maximum power value for the new conditions by filing

additional rate of spheres, taking into account the increasing volume of the mill due to wear of the lining. That is, in this case, the search for the extreme conditions of filling the grinding unit with both ore and balls is automatically performed, whether it is from liner wear or ball wear.

On the other hand, the extreme t

the power value in the process of the mill operation is compared in the summation block 7 with the current extreme power values and if the correlation coefficient is zero according to the obtained

differences are judged on lining wear.

Claims (2)

1. USSR Author's Certificate N ° 334887, cl. B 02C 25/00, 1971. 2. USSR author's certificate number 442830, cl. B 02C 17/00, 1972. / Oud register soup and npuffop Download pydtii Loading MufloS