RU2513936C2 - Abrasive material grain classifier - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to loose material size, shape and density separation and can be used to classification of abrasive grains in production of abrasive tools. Proposed device consists of the rotor fitted on shaft and engaged with motor shaft via clutch, intake chutes, tray coupled via pipeline with pump. Besides, classifier comprises suspension mixer communicated by pipeline with pump to optimise suspension state prior to feeding to rotor and composed by mixing device, motor and valve. Tray-type intake chutes with baffle plates are arranged one above the other on bed its height being adjusted by pins. Rotor represents a composite surface in the form of flat disc nearby rotational axis and hemisphere with locating conical hole for fitting o the shaft. Rotor shaft runs in rolling bearings inserted via sleeve in bearing barrel secured with cover and motor at said bed mounted with the help of posts on the plate.

EFFECT: higher efficiency of classification to size and shape and process efficiency.

6 cl, 2 dwg

Description

The invention relates to the field of separation of bulk powder materials into fractions according to their size, shape and density and can be used for liquid classification of grains of abrasive materials used in the manufacture of abrasive tools.

Known vibration table for separation by size and shape of particles of bulk materials, consisting of a deck and located on its perimeter on three sides of the receiving cells [1].

A disadvantage of the known vibrating table is the relatively low productivity of the classification process, which is 150 ... 1700 ct / h, which is associated with low speeds of movement of particles on the surface of the deck under the influence of vibration.

The closest in technical essence and the result obtained is the coolant supply station [2], which includes a device for the recovery and classification of abrasive grains from coolant, consisting of a rotor and a receiver for collecting fractions, the rotor is mounted on a shaft and connected through a coupling to the motor shaft. The installation contains receiving trays, a pallet connected by a pipeline to the pump.

A disadvantage of the known installation is the inability to continuously feed into the separation zone a suspension consisting of a working fluid and abrasive material, which reduces the productivity of the installation. At the same time, when the suspension is supplied, the abrasive material grains are not constantly maintained in suspension to prevent their deposition.

The claimed invention solves the problem of increasing the productivity of the process of classifying abrasive material by size and shape of grains.

The technical result is to ensure the continuity of the process of separation into fractions and a stable state of the suspension for separation.

According to the stated decision, the proposed installation for classifying grains of abrasive material, consisting of a rotor mounted on a shaft, connected through a coupling to the motor shaft, receiving trays, a pallet connected by a pipeline to a pump, includes a slurry mixer connected by a pipeline to a pump to bring it to the optimum state before feeding to the rotor, consisting of a housing, a mixing device, an electric motor and a valve.

The coupling consists of a sleeve in the form of a star, mounted on the shaft of the electric motor, a reciprocal sleeve, mounted on the shaft of the rotor, and a silicone gasket to compensate for the misalignment of the shafts.

The receiving trays are dish-shaped with reflectors and mounted one above the other on the base, adjustable in height with studs.

The rotor is a composite surface in the form of a flat disk near the axis of rotation and a hemisphere with a tapered bore for mounting on the shaft.

The rotor shaft is mounted on rolling bearings, pressed completely opposite through a sleeve in a bearing cup fixed together with a cover and an electric motor on a base mounted with racks on the plate.

To compensate for misalignment of the shafts, the bearing cup has a centering belt and is fixed with the electric motor to the base through the centering sleeve.

The proposed installation for classifying grains of abrasive material differs from the prototype by the introduction of an agitator into it, which makes it possible to solve the problem of continuously supplying a suspension to the separation zone consisting of a working fluid and grains of abrasive grains constantly kept in suspension. High performance of the process is achieved through the use of a thin-film flow and a centrifugal field, which is created by a rotor cantilevered on the shaft, rotating at high speeds, and also by increasing the concentration of grains in the suspension.

When the concentration of grains in the suspension in the range from 1 to 10%, the performance of the process of grading grains using the proposed system lies in the range from 100 to 1400 thousand car / h with a suspension flow rate of 12 l / min. At the same time, vibrating screens and air separators used only for the dimensional classification of grinding powders (40 ... 630 microns) have a capacity of up to 20 thousand car / h, cup centrifuges used for the dimensional classification of micropowders (1 ... 60 microns) and the vibration tables used for classification by size and shape are 150 ... 1700 ct / h [1]. Obviously, the use of a centrifugal liquid classification plant for abrasive material can significantly (5 ... 1000 times) increase the productivity of the process.

The invention is illustrated by drawings, in which figure 1 shows the installation of the liquid classification of grains by size and shape, figure 2 - coupling connecting the motor shaft and the rotor shaft.

The proposed installation (figure 1) for the classification of grains of abrasive material consists of a rotor 1, mounted on a shaft 2, which is mounted on rolling bearings 3, pressed completely through the sleeve 4 in the glass 5. The shaft 2 is connected through a coupling 6 to the shaft of the electric motor 7. Coupling 6 (FIG. 2) consists of a sleeve 8 in the form of a star, fixed on the shaft of an electric motor 7, a reciprocal sleeve 9, fixed on a shaft 2, and installed between them a silicone gasket 10. The electric motor 7 on the studs 11 through the sleeve 12 completely against the sleeve 5 together with cover 13 fastens on the basis of 14, mounted using racks 15 on the plate 16. On the basis of 14 with the help of the fitting 17 with a threaded rod is secured to the pallet 18, into which the housing 19 with the receiving trays 20 located inside, the height position of which is regulated by the sliding studs 21, is mounted. 19, a cover 22 and an agitator are installed, consisting of a housing 23, a mixing device 24, a cover 25 with an electric motor 26 fixed to it and a valve 27 that is connected to a replaceable fitting 28. A pump 29 is installed on the plate 16, the inlet of which is connected by a pipe a wire 30 with a fitting 17, and the outlet is connected by a pipe 31 to the mixer.

Installation for the classification of grains of abrasive material operates as follows. Powder classified abrasive material is poured into the mixer, where, mixed with a working fluid, such as water, forms a suspension. The rotational speed of the mixer motor 26 is selected so that there is no sediment at the bottom of the housing 23. The flow rate of the working fluid is regulated by the selection of a replaceable fitting 28 with the required diameter of the hole. By opening the valve 27, the prepared suspension by gravity through the nozzle 28 enters the surface of the rotor 1, the rotational speed of which is determined by the characteristics of the extracted grains and the working fluid. The spherical rotor used makes it possible to create a centrifugal inertial force field, the value of which varies along the generatrix of the rotor surface. This allows particles of various sizes to develop sufficient inertia to overcome surface tension forces and to break away from the free surface of the liquid at a given height from the base of the rotor. Grains which have broken off from the free surface of the fluid flow continue to move in the air along a straight horizontal path with great speed. The trays 20, forming the receiving compartments, are structurally equipped with reflectors, which eliminates the possibility of grain rebound into adjacent compartments or outside the receiver in a collision at high speeds with the surface of the tray. The working fluid after removing particles of the classified material from it enters the sump 18, from where the pump 29 re-feeds it into the mixer, thus providing continuous circulation of the working fluid. 5

The apparatus for classifying grains of abrasive material can be especially effectively used in the separation of abrasive grinding powders and micropowders according to grain size and shape for the purpose of their use in the manufacture of special abrasive tools with specified parameters and scope.

Information sources

1. Nikitin Yu.I. Manufacturing technology and quality control of diamond powders. - Kiev .: Science. Dumka, 1984. - 264 p.

2. RF patent for utility model No. 38666, IPC ⁷ V24V 55/03. Coolant supply station / Publ. 07/10/2004.

Claims (6)

1. Installation for the classification of grains of abrasive material, consisting of a rotor mounted on a shaft connected through a coupling to the motor shaft, receiving trays, a pallet connected by a pipeline to a pump, characterized in that it includes a suspension mixer connected to the pipeline with a pump to bring it to the optimum state before feeding to the rotor, consisting of a housing, a mixing device, an electric motor and a valve. 2. Installation for the classification of grains of abrasive material according to claim 1, characterized in that the coupling consists of a sleeve in the form of a star mounted on the shaft of the electric motor, a reciprocal sleeve fixed on the shaft of the rotor, and a silicone gasket to compensate for the misalignment of the shafts. 3. Installation for classifying grains of abrasive material according to claim 1, characterized in that the receiving trays are made in a plate shape with reflectors and are mounted on top of each other on a height-adjustable base with studs. 4. Installation for classifying grains of abrasive material according to claim 1, characterized in that the rotor is a composite surface in the form of a flat disk near the axis of rotation and a hemisphere with a tapered bore for mounting on the shaft. 5. Installation for the classification of grains of abrasive material according to claim 1, characterized in that the rotor shaft is mounted on rolling bearings, pressed by pressing through a sleeve in a bearing cup, fixed together with the lid and electric motor on a base mounted with racks on the plate. 6. Installation for classifying grains of abrasive material according to claim 5, characterized in that to compensate for misalignment of the shafts, the bearing cup has a centering belt and is secured with an electric motor to the base through the centering sleeve.

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