THEORETICAL AND EXPERIMENTAL INVESTIGATION OF THE MAGNETOELECTRIC SYSTEM, WHICH RECOGNIZES THE LARGE OF SUNS OF A SINGLE-SPIRAL CLASSIFIER

Abstract

Purpose. The aim of the work is to create a magnetoelectric system with permanent magnets, which perceives the coarse size of the sand of a single-helix classifier, by establishing the connection of the output signal with the measured quantity, eliminating the effect of disturbances on the result and justifying its parameters.Methodology. The studies carried out on the basis of the use of methods of the theory of electrical engineering, magnetic systems with permanent magnets, galvanomagnetic transducers, probabilities, random processes, statistics, regression analysis, sensitivity, differential calculus, rock magnetism, determination of the physical properties of matrix material when impurities are added to it with others explicitly expressed properties, the classification of enrichment products.Findings. The process of the rate of change of the volume of solid in a controlled volume of space through which the sand material moves is described mathematically. The limits of the volume of the controlled volume at which the sensitivity is still sufficient are determined. The theoretical dependences of the rate of change of the solid volume in the controlled volume on the size of the sands at different speeds are obtained. It is established that the state of the controlled volume is best estimated by the magnetic method. A magnetoelectric system with permanent magnets has been developed, which has optimal parameter values and an induction winding containing up to 25,000 turns, and in one of the pole pieces of which a Hall transducer is installed in a continuous slot. The magnetic system near the air gap creates in the material a magnetic field 5 × 20 × 60 mm in size with almost the same intensity. Ed. The magnetoelectric system practically changes linearly with the increase in the size of the material. It depends on the content of magnetic iron in the solid, which is compensated by the use of the signal from the Hall converter. Correlation connection between the induced emf. and the size of the sand is close, in character corresponds to the theoretical dependence.Originality. The magnetoelectric system for controlling the weighted average size of the sands of a single-helix classifier was created for the first time and allows to solve the actual problem of automation of the first stages of ore crushing. For the first time, a mathematical relationship between the rate of change in the volume of solid in the controlled volume of the flow and the size of the sands, which is the basis for the creation of a magnetoelectric system, is obtained. The magnetoelectric system is improved by the execution of structural elements that create a magnetic field of 5 × 20 × 60 mm in size and the introduction of a Hall converter that reacts to the content of magnetic iron in a solid and allows to increase the accuracy of the measurement.Practical value. The practical value of the work lies in the fact that the magnetoelectric system is grounded, which makes it possible to develop a means of measuring the weighted average size of sands in industrial conditions and by automating to affect the reduction of the cost of iron ore concentrate.