CN209798043U - A device for purifying aluminum alloy melt by offset powder spraying - Google Patents

Abstract

The utility model belongs to the non ferrous metal field of purifying relates to a device that aluminium alloy fuse-element biasing was dusted powder and is purified. It includes: the device comprises a spiral feeding quantitative gas-powder mixing mechanism consisting of a variable frequency motor (1), a hopper (2), a screw (3) and a gas-powder mixing chamber (6), an offset rotary blowing device (7) connected with the gas-powder mixing mechanism, and a crucible (10) separated into a purifying chamber (9) and a filtering chamber (11) by a partition plate (14), wherein a ceramic foam filtering plate (13) is arranged above the filtering chamber (11). The utility model discloses can be steady, continuous carry out purification treatment, show improvement aluminium melt purifying effect to the aluminium melt.

Description

A device for purifying aluminum alloy melt by offset powder spraying

technical field

The utility model belongs to the field of non-ferrous metal metallurgy, in particular to a device for purifying aluminum alloy melt by offset powder spraying.

Background technique

Melt purification is a key technology to ensure the metallurgical quality of aluminum alloy materials. The main purpose of purifying the aluminum alloy melt is to remove the hydrogen content and oxidized inclusions in the melt, thereby improving the quality of the aluminum alloy. The methods of purifying aluminum melt mainly include: solvent method, gas blowing method, rotary blowing method, etc. The commonly used refining agent is added to purify aluminum melt, although it can play a certain role in refining, but because the refining agent is easy to gather together, in order to achieve the effect, the amount added will be large. Therefore, the refining method of gas + solvent has also appeared. After searching, it was found that "a spraying device" participated in the patent application number: 20092014473.8. After mixing the gas and solvent, it is directly injected into the melt, and the solvent is distributed on the surface of the bubbles in the melt to achieve the effect of double refining. But in this method, the bubbles formed are not small enough, and the amount of solvent is relatively large. Shanghai Jiaotong University developed the "Aluminum Alloy Melt Purification Method", see patent application number: 0510026593.X, the upper part of the purification device uses the method of rotary injection to blow the purified gas into the aluminum melt, and at the same time, the bottom of the device is equipped with breathable bricks to Purge gas is blown into the melt. Shanghai Institute of Mechanical and Electrical Engineering has developed "a method and device for degassing aluminum melt with top-angle compound blowing", see patent application number: 0910044935.9, the purification device blows the purified gas from the rotating The peripheral air inlet of the purification unit is blown into the aluminum melt. These methods all belong to the center rotary injection, in order to obtain finer and better bubble distribution, high-speed rotation is often required to achieve. However, as the speed increases, eddies and vibrations will appear on the melt surface, the protective film on the melt surface will be destroyed, and the slag and air on the surface will enter the melt, increasing the impurities of the melt; The body reacts, that is, the melt is burned, and more hydrogen and inclusions are generated. In actual production, in order to prevent the vortex of the liquid surface, a baffle is usually set near the rotor. However, when the melt is refined, the temperature of the melt is very high, the rotor rotates very fast, the melt has a strong erosion and corrosion effect on the baffle, the working environment of the baffle is very harsh, the service life is not high, the cost is high, and the falling off Material intrusion into the melt can cause contamination and ultimately affect the quality of the melt. Suzhou Boneng Furnace Technology Co., Ltd. has developed "a spoiler structure for a degassing device", see patent application number: 201210414279.9, the device is provided with a raised spoiler block on each of the four sides of the degassing tank lining to eliminate liquid face swirl. This method increases the complexity of the degassing tank, and at the same time does not solve the problem that the spoiler is easily washed off and enters the melt.

Contents of the invention

The purpose of the utility model is to overcome the deficiencies of the above-mentioned prior art, to provide a continuous and stable on-line purification of aluminum melt, which significantly increases the refining agent purification action interface, action range, prolonging action time, and low refining agent dosage, which is convenient Replacement, high service life filter, simple structure, low cost aluminum melt purification device.

The utility model is realized in the following ways:

A device for offset powder injection and purification of aluminum alloy melt, which is characterized by a screw feeding and quantitative gas powder mixing mechanism composed of a frequency conversion motor, a hopper, a screw, and a gas powder mixing chamber, and an offset rotating mechanism connected with the gas powder mixing mechanism The blowing device is divided into a crucible of a clean room and a filter room by a partition, and a ceramic foam filter plate is arranged above the filter room. The melt inlet is set above the clean room, the melt flows through the clean room from top to bottom, the melt outlet is set above the filter room, and the purified melt passes through the filter plate from bottom to top and then flows out from the melt outlet. The purified gas is blown into the gas-powder mixing chamber, the refining agent is put into the hopper, and the variable-frequency motor drives the screw to flow quantitatively into the gas-powder mixing chamber and fully mixes with the purified gas to form a gas-powder flow, which is then passed into the biased rotary blowing device to form a gas-powder flow. Fine, uniform purifying bubbles of refining agent dispersedly distributed on the surface.

The above-mentioned device for purifying aluminum alloy melt by offset powder spraying is characterized in that the rotating speed of the screw is controlled by a frequency conversion motor, so that the refining agent can be quantitatively sent into the air powder mixing chamber.

The above-mentioned device for purifying aluminum alloy melt by offset powder spraying is characterized in that the content of refining agent in the gas powder flow is 0.1-0.5% of the melt flow rate at the melt inlet.

The above-mentioned device for purifying aluminum alloy melt by offset powder spraying is characterized in that the distance from the rotor of the offset rotary spraying device to the bottom of the clean room is 50-300 mm, and the distance from the center axis of the rotor to the center of the clean room is the bottom of the clean room. 1/5 to 1/3 of the diameter.

The device for purifying aluminum alloy melt by offset powder spraying is characterized by a ceramic foam filter plate with a specification of 40-50ppi.

When the utility model is used, the dry refining agent is put into the hopper, and the frequency conversion motor gives the screw a reasonable rotational speed, so that the feeding flow rate of the refining agent is 0.1-0.5% of the melt flow rate, and the purified gas is fully mixed in the gas-powder mixing chamber. Finally, it is blown into the rotary blowing device, sheared by the high-speed rotating blades, and the refining agent will be dispersed and distributed on the surface of the fine and uniform purification bubbles. The purified bubbles of the refining agent dispersed on the surface rise slowly in the clean room, fully mix and collide with the descending melt, the hydrogen in the melt diffuses into the rising bubbles, and at the same time the rising bubbles collide with the non-metallic inclusions in the melt , absorb and carry them up to the buoyancy. The dispersed refining agent increases the concentration gradient of hydrogen diffusion into the bubbles and the wettability of inclusions, so it is easier to absorb hydrogen and adsorb inclusions, and the melt is also stirred, thereby significantly increasing the refining agent and purifying bubbles. The effective interface and range of action prolong the contact time, and the stirring also promotes the aggregation of fine inclusions, which is more conducive to flotation removal. Offset stirring method, the tangential flow, pressure field and velocity field of the melt around the rotor are asymmetrically distributed, and it is not easy to generate centripetal acceleration and centrifugal force, so there will be no vortex on the liquid surface during refining, and it can be made without adding baffles. The liquid level is stable. After the melt passes through the clean room, the large-sized non-metallic inclusions are effectively removed, and then after passing through the 40-50ppi foam ceramic filter plate, the non-metallic inclusions above 10 μm are completely removed, and the melt passes through the filter plate from bottom to top, and the impurity particles Blocked at the lower end of the filter, when they are agglomerated to a certain size, they will fall off and settle from the filter due to their own weight, thereby realizing the self-purification of the filter and greatly improving the service life of the filter.

Description of drawings

Fig. 1 is a structural representation of the utility model.

In the figure, 1 is the frequency conversion motor, 2 is the hopper, 3 is the screw, 4 is the purified gas, 5 is the gas-powder flow, 6 is the gas-powder mixing chamber, 7 is the offset rotary injection device, 8 is the melt inlet, 9 10 is a crucible, 11 is a filter chamber, 3 is a ceramic foam filter plate, and 14 is a partition.

Detailed ways

The aluminum melt flows into the purification chamber 9 from the melt inlet 8 from top to bottom at a flow rate of 400kg/h, and the temperature of the aluminum melt is 750°C; the bottom diameter of the purification chamber 9 is 400mm, and the liquid level is 350mm; the dry refining agent is put into In the hopper 2, adjust the frequency conversion motor 1 to control the rotation speed of the screw 3, so that the flow rate of the refining agent is 0.6kg/h, and the industrial argon gas with a purity of 99.9% is blown into the gas-powder mixture at an intake rate of 160m1/min and a gas pressure of 0.1MPa Chamber 6, fully mixed to form gas-powder flow 5 into the offset rotary spraying device 7; the rotor diameter of the offset rotary powder spraying device 7 is 40 mm, 60 mm away from the bottom of the clean room, and the central axis of the rotor is offset from the center of the clean room 9 The distance is 100mm, the rotation speed of the rotor is 600rpm, the shearing action of the rotor forms fine and uniform small bubbles that rise slowly and disperse the refining agent, and collide with the reverse melt for degassing and impurity removal; the processed melt enters to the filter chamber 11, and then pass through the filter plate 13 from bottom to top, the foam ceramic filter plate whose specification is 50ppi, and finally flow out from the melt outlet 12. During the purification process, the liquid surface is stable without vortex, the melting efficiency and the quality of the melt are improved, and a high-quality aluminum melt with a hydrogen content of 0.08ml/100g and a non-metallic inclusion below 10μm of less than 0.02% can be obtained.

Claims (5)

1. The utility model provides an aluminum alloy melt biasing dusting purification's device, its characterized in that includes by inverter motor (1), hopper (2), screw rod (3), the spiral feed ration gas powder mixing mechanism that gas powder mixing chamber (6) are constituteed, biasing rotatory jetting device (7) of being connected with gas powder mixing mechanism, crucible (10) of being separated into clean room (9) and filter chamber (11) by baffle (14), set up ceramic foam filter (13) above filter chamber (11), fuse-element import (8) are established above clean room (9), fuse-element top-down flows through clean room (9), fuse-element export (12) are established above filter chamber (11), the fuse-element after the purification flows from fuse-element export (12) after passing through filter (13) from bottom to top, purified gas (4) are blown into in gas powder mixing chamber (6), the refining agent is put into hopper (2), drive screw rod (3) ration by inverter motor (1) and flow into gas powder mixing chamber (6) and purified gas (4) in with the clean gas (4) ) Fully mixing to form gas powder flow (5), and then introducing the gas powder flow into an offset rotary blowing device (7) to form fine and uniform purified bubbles which disperse and distribute the refining agent on the surface.

2. The aluminum alloy melt offset powder injection purification device according to claim 1, wherein the rotation speed of the screw (3) is controlled by the variable frequency motor (1), and the quantitative feeding of the refining agent into the gas-powder mixing chamber (6) can be realized.

3. The aluminum alloy melt bias powder injection purification device according to claim 1, wherein the content of the refining agent in the gas powder flow (5) is 0.1-0.5% of the melt flow at the melt inlet (8).

4. The aluminum alloy melt offset powder spraying purification device according to claim 1, wherein the distance from the rotary head of the offset rotary spraying device (7) to the bottom of the purification chamber (9) is 50-300 mm, and the distance from the central axis of the rotary head to the center of the purification chamber (9) is 1/5-1/3 of the diameter of the bottom of the purification chamber (9).

5. The aluminum alloy melt bias powder injection purification device according to claim 1, wherein the ceramic foam filter plate (13) has a specification of 40-50 ppi.