RU72871U1 - DEVICE FOR VIBROAERATION MIXING OF BULK MATERIALS - Google Patents

Abstract

The device is designed for mixing bulk materials in powder metallurgy, construction and other industries. The device comprises a mixing chamber formed by the side walls and the base and a vibration exciter. In the upper part, the mixing chamber is equipped with a sealed lid and is mounted on a vibration-generating unit. The side walls of the chamber are double, with a free space of 2 ÷ 10 mm wide between them. At the upper and lower edges of the inner wall, a series of holes with a diameter (d) of 10–50 times the maximum particle diameter of the bulk material is successively made. A valve is installed inside the chamber’s working space, which is a hollow body that follows the shape of the chamber walls and mates with the inner wall in an easy-going fit, the height of which is 1.5d less than the wall height; a crown with a protrusion height of 5 ÷ 10d is made along the upper edge of the valve.

The device provides increased efficiency and mixing speed due to the destruction of conglomeration formations.

Description

The utility model relates to mixture preparation, and specifically to devices for mixing bulk materials, and can be used in powder metallurgy, construction and other industries.

Known aerodynamic device for mixing bulk materials, which contains a conical body, a cover with ducts for air outlet, a centrifugal fan wheel with blades, a working chamber, on the side surface of which are installed several tangential nozzles for introducing air together with the components of the mixture. Tangential nozzles have different diameters and are arranged sequentially increasing from a smaller diameter to a larger one on the same horizontal plane, and the height of the blades of the centrifugal fan wheel must be equal to or not less than the largest diameter of the suction tangential nozzle (RF patent No. 2294795, IPC B01F 13/02, 13 / 18, publ. 2007.03.10).

The disadvantages of this device are:

- its inapplicability to fine powders due to the presence of branch pipes for air outlet and the creation of the required vacuum in the mixer,

- the need to install an additional device (fan) to create a suction effect in the mixer,

- lack of ability to destroy conglomerates.

Also known is a device (prototype) for mixing bulk materials containing a container with a mesh base, vibration exciter

and an air blower, characterized in that the air blower is made in the form of a flexible membrane mounted under a mesh base, in the center of which a resonant mass is attached, which is made of a set of plates (RF patent No. 2131414, IPC B01F 3/18, 11/00, publ. 1999.07 .twenty).

The disadvantages of this device are:

- its inapplicability to fine powders due to the presence of a retentive mesh base and open communication of the chamber with the surrounding atmosphere;

- the need to install an additional device for the membrane of the blower;

- low efficiency of the pulsating air stream due to pressure balancing in the sub-powder and super-powder zones.

The objective of the proposed technical solution is to create a device for mixing bulk materials of various morphology, chemical and particle size distribution, including high and ultrafine.

The technical result of this utility model is to increase the efficiency and speed of mixing, the destruction of conglomeration formations and ensuring the invariability of the chemical composition of the mixtures.

The specified technical result is achieved in that the device for vibration-aeration mixing of bulk materials containing a mixing chamber formed by the side walls and a base and a vibration exciter, characterized in that the mixing chamber is provided with a sealed cover and installed on the vibration generating unit, the side walls of the chamber are made double, with a free space of 2 ÷ 10 mm wide between them, and at the upper and lower edges of the inner wall, a series of holes d and diameter (d) 10 ÷ 50 times the maximum particle diameter

bulk material, a valve is installed inside the chamber’s working space, which is a hollow body that follows the shape of the chamber walls and mates with the inner wall in an easy-to-fit fit, the height of which is 1.5 d less than the wall height; a crown with a height of protrusions 5 is made along the upper edge of the valve ÷ 10d. Indicated features of the device:

- the design of the housing of the mixing chamber in the form of a double wall with a space between them with a width of 2 ÷ 10 mm, which acts as a venting channel;

- execution on the upper and lower edges of the inner wall, holes with a diameter (d) of 10 ÷ 50 times the maximum particle diameter of the granular material, provides free passage of gases between the inner cavity of the chamber and the wall space;

- installation inside the mixing chamber of the valve, which is a hollow body that follows the shape of the chamber walls and mates with the inner wall in an easy-to-fit fit, the height of which is 1.5 d less than the wall height, a crown is made along the upper edge of the valve, which allows air to pass at the upper the extreme position of the piston, with the height of the protrusions 5 ÷ 10d.

The essence of these signs is as follows: the design of the housing of the mixing chamber in the form of a double wall with a space between them of 2 ÷ 10 mm wide is made for air to pass from the super-powder zone to the powder one when the powder moves upward relative to the mixing chamber.

A series of holes along the upper and lower edges of the inner wall is made in order to ensure the passage of air between the mixing zone and the wall space. The diameter of the holes (d) is 10 ÷ 50 times larger than the maximum particle diameter of the granular material ensures the absence of blockage by their powder mass.

Installation inside the mixing chamber of the valve, which is a hollow body, in the form of a repeating chamber wall and mating with the inner wall for easy-landing, creates a condition for obtaining increased air pressure in the powder zone. Its shape and geometric dimensions provide, at given vibration frequencies, the coordination of the movement of the trap with the movement of the powder mass.

The figure shows a diagram of a device for vibratory aeration mixing of bulk materials. The device consists of a base 1 and a top cover 2, which through elastic gaskets 3 rest on the outer 4 and inner 5 walls, hermetically locking the mixing chamber. The inner wall 5 is equipped with successive rows of 6 and 7 holes for the passage of air (gas), made at its upper and lower edges. A cavity 8 is formed between the outer and inner walls for air (gas) circulation. Inside the working space of the mixing chamber 9, a valve 10 is installed, equipped with a crown 11, repeating the shape of the inner wall of the chamber and mating with it for easy landing. A powder composition 12 is placed inside the valve. The device is mounted on a vibration unit consisting of a bed 13 and a vibration mechanism 14.

The inventive device for vibrational mixing of finely divided bulk materials, works as follows. Open the top cover 2 of the mixing chamber 9, formed by the side walls 4,5 and the base 1, and a set of mixed bulk materials 12 is poured randomly into the valve 10. Then, the cover 2 with elastic gaskets 3 is hermetically closed and using a vibration mechanism 14, installed on the frame 13, give the mixing chamber oscillatory movements in a vertical plane. (We give a description of one cycle of motion of the mixing chamber). When the mixing chamber moves down, the powder mass 12 and the valve 10 rise upward relative to the mixing chamber. Wherein

the powder array 12 pushes air (air movement is indicated by arrows) from the zone above the powder through the crown 11 into the openings 6 at the upper edge of the inner wall 5, along the interwall space 8 and through the openings 7 at the lower edge, the air flows into the powder space. When the mixing chamber moves upward, the valve 10, having a limited stroke, closes the bottom row of holes 7 in the inner wall and the powder moving down compresses the air, which, passing through the voids of the powder massif 12, destroys conglomerates and intensifies the mutual movement of particles of bulk material, accelerating and enhancing the process mixing.

The described installation was manufactured at the Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences. It was mixed with metal powders: 65 vol.% Al, 35 vol.% Pb, 5 vol.% Cu particle size distribution, respectively 50 ÷ 60 microns, 3 ÷ 5 microns, 2 ÷ 10 microns and the second composition of the charge 80 vol.% Cr, 15 vol.% NbC, 5 vol.% graphite, particle size distribution, respectively 2 ÷ 10 μm, 10 ÷ 20 μm, 20 ÷ 60 μm. After mixing in the inventive device for 30 seconds, a qualitatively mixed mixture of powders and the complete disappearance of conglomerates were obtained. Checking the quality of mixing was carried out visually, on samples taken from different sections of the powder array, with a sixty-fold increase. Verification showed the complete absence of conglomerates and the uniformity of the composition of the powder mixture.

Claims (1)

A device for vibration-aeration mixing of bulk materials containing a mixing chamber formed by the side walls and the base and a vibration exciter, characterized in that the mixing chamber is equipped with a sealed cover in the upper part and is mounted on the vibration oscillation generating unit, the side walls of the chamber are double, with a free space of 2 ÷ 3 10 mm between them, and at the upper and lower edges of the inner wall, a series of holes with a diameter (d) of 10 ÷ 50 times the maximum diameter particles of bulk material, a valve is installed inside the working space of the chamber, which is a hollow body that follows the shape of the chamber walls and mates with the inner wall in an easy-going fit, the height of which is 1.5d less than the wall height, a crown with a height of protrusions 5 is made on the upper edge of the valve ÷ 10d.