CN117450434A - Magnesium alloy smelting gas protection device and application thereof - Google Patents
Magnesium alloy smelting gas protection device and application thereof Download PDFInfo
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- CN117450434A CN117450434A CN202311659583.4A CN202311659583A CN117450434A CN 117450434 A CN117450434 A CN 117450434A CN 202311659583 A CN202311659583 A CN 202311659583A CN 117450434 A CN117450434 A CN 117450434A
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- Prior art keywords
- gas
- valve
- path
- magnesium alloy
- mass flow
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- 229910000861 Mg alloy Inorganic materials 0.000 title claims abstract description 34
- 238000003723 Smelting Methods 0.000 title claims abstract description 27
- 230000001105 regulatory effect Effects 0.000 claims abstract description 49
- 238000002156 mixing Methods 0.000 claims abstract description 43
- 238000001035 drying Methods 0.000 claims abstract description 23
- 230000001276 controlling effect Effects 0.000 claims abstract description 19
- 238000003860 storage Methods 0.000 claims abstract description 11
- 238000004891 communication Methods 0.000 claims description 2
- 239000007789 gas Substances 0.000 description 154
- 230000001681 protective effect Effects 0.000 description 18
- 238000000034 method Methods 0.000 description 5
- 230000003247 decreasing effect Effects 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 229910018503 SF6 Inorganic materials 0.000 description 2
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 230000002829 reductive effect Effects 0.000 description 2
- 238000007670 refining Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 230000000903 blocking effect Effects 0.000 description 1
- 238000009960 carding Methods 0.000 description 1
- 230000004907 flux Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000000979 retarding effect Effects 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 239000011593 sulfur Substances 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 229960000909 sulfur hexafluoride Drugs 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D3/00—Arrangements for supervising or controlling working operations
- F17D3/03—Arrangements for supervising or controlling working operations for controlling, signalling, or supervising the conveyance of several different products following one another in the same conduit, e.g. for switching from one receiving tank to another
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B26/00—Obtaining alkali, alkaline earth metals or magnesium
- C22B26/20—Obtaining alkaline earth metals or magnesium
- C22B26/22—Obtaining magnesium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B9/00—General processes of refining or remelting of metals; Apparatus for electroslag or arc remelting of metals
- C22B9/05—Refining by treating with gases, e.g. gas flushing also refining by means of a material generating gas in situ
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C1/00—Making non-ferrous alloys
- C22C1/02—Making non-ferrous alloys by melting
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C23/00—Alloys based on magnesium
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D1/00—Pipe-line systems
- F17D1/02—Pipe-line systems for gases or vapours
- F17D1/04—Pipe-line systems for gases or vapours for distribution of gas
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D5/00—Protection or supervision of installations
- F17D5/005—Protection or supervision of installations of gas pipelines, e.g. alarm
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Organic Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Life Sciences & Earth Sciences (AREA)
- Environmental & Geological Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Abstract
A magnesium alloy smelting gas protection device and application thereof comprise a multi-path gas concentration regulation and control system, a gas mixing system and a computer control center. Each path of gas concentration regulating and controlling system comprises a gas storage tank, a pressure regulating valve, a drying tank, a mass flow controller, a gas inlet pipe and an electric control gas valve which are connected in sequence; the gas mixing system comprises a gas mixing tank, a mixed gas pressure regulating valve and a pressure gauge which are connected in sequence; each path of gas concentration regulating and controlling system is connected to a gas mixing tank of mixed gas through an electric control gas valve. The computer control center is respectively and electrically connected with the mass flow controller and the electric control gas valve of each path of gas concentration regulating and controlling system. The invention has simple and convenient operation, can adjust the gas mixing proportion, control the opening and closing of a single gas path and the percentage of valve positions according to the requirements, observe the real-time flow of gas and the display of the valve positions, and control the quality of the inflowing gas in real time so as to achieve the purposes of controlling the gas mixing and the gas component proportion, accurately configure each path of gas component and have better application prospect.
Description
Technical Field
The invention belongs to the technical field of metal smelting, and particularly relates to a magnesium alloy smelting gas protection device and application thereof in magnesium alloy smelting.
Background
The magnesium alloy melt protection method commonly used at present mainly comprises the following steps: flux protection, alloying flame retarding, and gas protection. Gas protection is a commonly used technique in the magnesium alloy industry.
Because magnesium alloy is relatively active in chemical property, high-temperature oxidation is serious and the like, the large-scale application of the magnesium alloy is hindered to a certain extent. Current state of the art: firstly, the existing magnesium alloy melting furnace is not provided with a multi-element gas mixing device; the problem of the largest protective gas is that the protective gas is corrosive gas such as sulfur hexafluoride SF6 and sulfur dioxide SO 2 After the mixing is uneven, the local sulfur content concentration of the atmosphere is increased, the parts such as a crucible, a quantitative pump and the like are corroded in a large area, and the service life is greatly reduced; thirdly, under the high-temperature liquid state, the magnesium alloy cannot form a compact combustion-supporting protective film due to the factors of uneven mixing, uneven covering and the like of the protective gas, so that the magnesium alloy is seriously oxidized, the quality of the magnesium alloy is reduced, meanwhile, the liquid state fluidity of the magnesium alloy is deteriorated, and the production safety and the product quality are affected by the effects of sticking materials, blocking a pouring tube and the like. Most of the existing similar gas mixing devices only adopt special stainless steel wire dressing net for carding and mixing, the mixing effect is poor, the mixing uniformity is low, and the device is not suitable for magnesium alloy melting furnace equipment.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provides a magnesium alloy smelting gas protection device and application thereof in magnesium alloy smelting, and the purpose of controlling gas mixing and controlling gas component proportion and mixing is achieved by accurately controlling the mass flow of multiple paths of gas to be introduced, so that multiple paths of gas components are accurately configured.
The invention is realized by the following technical scheme.
The invention relates to a magnesium alloy smelting gas protection device which comprises a multi-path gas concentration regulation and control system, a gas mixing system and a computer control center.
Each path of gas concentration regulating and controlling system comprises a gas storage tank, a pressure regulating valve, a drying tank, a mass flow controller, a gas inlet pipe and an electric control gas valve; the air storage tank, the pressure regulating valve, the drying tank, the mass flow controller, the air inlet pipe and the electric control gas valve are connected in sequence.
The gas mixing system comprises a gas mixing tank, a mixed gas pressure regulating valve and a pressure gauge; the gas mixing tank, the mixed gas pressure regulating valve and the pressure gauge are connected in sequence.
Each path of gas concentration regulating and controlling system is connected to a gas mixing tank of mixed gas through a pipeline by an electric control gas valve.
The computer control center comprises a computer, a power module and a communication module to form a control center, and the control center is respectively and electrically connected with the mass flow controllers and the electric control gas valves of each path of gas concentration regulation and control system, and controls the flow through multipath mass flow controller software in the computer.
The invention relates to an application of a magnesium alloy smelting gas protection device in magnesium alloy smelting.
The working flow of the magnesium alloy smelting gas protection device provided by the invention is as follows: opening a valve of the gas storage tank, enabling the multipath protective gas in a high-pressure state to enter a drying tank for drying through respective pressure regulating valves, controlling the multipath protective gas through multipath mass flow controllers after drying and feeding back the multipath mass flow controllers to multipath mass flow control software in a computer, setting the proportion of the protective gas flowing in through the software, controlling the protective gas to be in a set proportion through respective electric control gas valves, injecting the protective gas into a gas mixing tank, and outputting the protective gas into a smelting furnace through a mixed gas pressure regulating valve to serve as the protective gas in the magnesium alloy smelting process.
The multiple paths of protective gases are mixed in proportion and are subjected to drying treatment. The multipath mass flow controller not only has the function of a mass flowmeter, but also can automatically control the gas flow, namely, a user can set the flow according to the needs and automatically fix the flow on a set value, and even if the system pressure fluctuates or the ambient temperature changes, the system pressure cannot deviate from the set value. The automatic control gas flow stabilizer can be manually set or connected with a computer, and the inflow gas quality can be controlled in real time.
Compared with the prior art, the invention has the following advantages and outstanding effects: the invention adopts the multi-path mass flow controller to connect with the computer for control, has simple and convenient operation, can adjust the gas mixing percentage according to the self requirement, controls the opening and closing of a single-path gas path and the valve position percentage, can observe the real-time flow and the valve position display of the gas, can control the quality of the inflowing gas in real time, achieves the purposes of controlling the gas mixing and controlling the gas component proportion, and accurately configures each path of gas component.
Drawings
Fig. 1 is a schematic view of a magnesium alloy smelting gas protection apparatus according to example 1. In fig. 1: 1 is an Ar gas storage tank; 2 is Ar pressure regulating valve; 3 is a drying tank I; 4 is a mass flow controller I; 5 is an air inlet pipe I; 6 is an electric control gas valve I; 7 is a computer; 8 is CO 2 A gas storage tank; 9 is CO 2 A pressure regulating valve; 10 is a drying tank II; 11 is a mass flow controller II; 12 is an air inlet pipe II; 13 is an electric control gas valve II; 14 is a gas mixing tank; 15 is a gas pipe; 16 is a mixed gas pressure regulating valve; 17 is a pressure gauge; 18 is a smelting furnace.
FIG. 2 is a flow chart of the R2MFC multi-path flow controller control system software.
Detailed Description
The invention will be further illustrated by way of example with reference to the accompanying drawings. It is to be understood that these examples are illustrative of the present invention and are not intended to limit the scope of the present invention.
The mass flow controllers used in the following examples of the present invention employ R2MFC multi-path flow controllers.
Example 1
As shown in fig. 1, the magnesium alloy smelting gas protection device in this embodiment includes two paths of protection gas, a computer 7, a gas mixing tank 14, a gas pipe 15, a mixed gas pressure regulating valve 16, a mechanical pressure gauge 17 and a smelting furnace 18.
Two paths of protective gas, one path of which comprises an Ar gas storage tank 1, an Ar gas pressure regulating valve 2, a drying tank I3, a mass flow controller I4, an air inlet pipe I5 and an electric control gas valve I6. Ar gas holder 1, ar gas air-vent valve 2, drying jar I3, mass flow controller I4, intake pipe I5, automatically controlled gas valve I6 link to each other in proper order.
Another way comprises CO 2 Gas storage tank 8, CO 2 Pressure regulating valve 9, drying tank II 10, mass flow controller II 11, air inlet pipe II 12, electric control gas valve II 13 and CO 2 Gas storage tank 8, CO 2 The pressure regulating valve 9, the drying tank II 10, the mass flow controller II 11, the air inlet pipe II 12 and the electric control gas valve II 13 are connected in sequence.
The two paths of protective gases are input into a gas mixing tank 14 through respective electric control gas valves, and are input into a smelting furnace 18 through a gas pipe 15 and a mixed gas pressure regulating valve 16. The mechanical pressure gauge 17 monitors the pressure of the mixed shielding gas.
The specific steps of the magnesium alloy smelting gas protection method in the embodiment are as follows:
opening an Ar gas pressure regulating valve 2, a mass flow controller I4 and a mixed gas pressure regulating valve 16, enabling Ar gas to enter a drying tank I3 for drying after passing through the Ar gas pressure regulating valve 2, enabling the dried gas to pass through the mass flow controller I4, enabling the mass flow controller to feed back the mass of the flowing gas to R2MFC multipath flow controller software in a computer, enabling the computer to regulate Ar mass in real time by controlling an electric control gas valve I6, enabling the Ar gas to enter a mixed gas tank 14 at 0.2MPa, and enabling the Ar gas to enter the mixed gas pressure regulating valve 16 and a pressure gauge 17 through the mixed gas tank 14 for stable flow and pressure output.
Turning on CO 2 Pressure regulating valve 9, mass flow controller II 11, mixed gas pressure regulating valve 16, CO 2 Gas and its preparation methodThrough CO 2 The gas enters a drying tank II 10 for drying after a pressure regulating valve 9, the dried gas passes through a mass flow device II 11, the mass flow device feeds back the R2MFC multipath flow controller software in a computer through the mass of the flowing gas, and the computer controls an electric control gas valve II 13 to perform real-time CO 2 The mass is regulated, then the mixture enters the gas mixing tank 14 at 0.6MPa, and the mixture enters the gas mixing pressure regulating valve 16 and the pressure gauge 17 through the gas mixing tank 14 to carry out stable flow and pressure output.
Ar and CO 2 The gas enters a gas mixing tank 14 according to the proportion of 5:2, the gas mixing tank 14 adjusts the gas entering amount, and two paths of gas with the same pressure are output, so that the mixed gas is uniform; the mixed gas pressure regulating valve 16 simultaneously controls Ar and CO 2 By adjusting the pressure of the mixed gas pressure regulating valve 16, ar gas and CO can be obtained 2 The pressure is increased or decreased simultaneously, so that the respective flow is increased or decreased simultaneously, and the originally set proportion of the two gases is kept approximately unchanged.
And (3) placing the magnesium alloy cast ingot subjected to the preheating treatment into a closed smelting furnace, and heating to raise the temperature. When the temperature reaches 600 ℃, introducing mixed protective gas with the flow rate of 7L/min in a uniform proportion; in the presence of protective gas, controlling the temperature at 650 ℃, refining and stirring after the magnesium alloy is melted, and standing for 30 minutes for subsequent processing.
Example 2
The structure of the magnesium alloy smelting gas protection device in this embodiment is the same as that in embodiment 1.
The specific steps of the magnesium alloy smelting gas protection method in the embodiment are as follows:
opening an Ar pressure regulating valve 3, a mass flow controller I4 and a mixed gas pressure regulating valve 16, enabling Ar gas to enter a drying tank I3 for drying after passing through the Ar pressure regulating valve 2, enabling the dried gas to pass through the mass flow controller I4, enabling the mass flow controller to feed back to R2MFC multipath flow controller software in a computer through the mass of the gas flowing through the mass flow controller, enabling the computer to regulate Ar mass in real time through controlling an electric control gas valve 6, enabling the Ar gas to enter a gas mixing tank 14 at 0.2MPa, and enabling the Ar gas to enter the mixed gas pressure regulating valve 16 and a pressure gauge 17 through the gas mixing tank 14 for stable flow and pressure output.
Turning on CO 2 Pressure regulating valve 9, mass flow controller II 11, mixed gas pressure regulating valve 16, CO 2 Gas passing through CO 2 The gas enters a drying tank II 10 for drying after a pressure regulating valve 9, the dried gas passes through a mass flow device II 11, the mass flow device feeds back the R2MFC multipath flow controller software in a computer through the mass of the flowing gas, and the computer controls an electric control gas valve II 13 to perform real-time CO 2 The mass is regulated, then 0.6MPa enters the gas mixing tank 14, and then enters the gas mixing pressure regulating valve 16 and the pressure gauge 17 through the gas mixing tank 14 to carry out stable flow and pressure output.
Ar and CO 2 The gas enters a gas mixing tank 13 according to the ratio of 9:4, the gas mixing tank 13 adjusts the gas entering amount, and 2 paths of gas with the same pressure are output, so that the mixed gas is uniform; the mixed gas pressure regulating valve 19 simultaneously controls Ar and CO 2 Ar and CO can be obtained by adjusting the pressure of the mixed gas pressure regulating valve 16 2 The pressure is increased or decreased simultaneously, so that the respective flow is increased or decreased simultaneously, and the originally set proportion of the two gases is kept approximately unchanged.
And (3) placing the magnesium alloy cast ingot subjected to the preheating treatment into a closed smelting furnace, and heating to raise the temperature. When the temperature reaches 500 ℃, introducing mixed protective gas with the flow rate of 13L/min in a uniform proportion; in the presence of protective gas, controlling the temperature at 700 ℃, refining and stirring after the magnesium alloy is melted, and standing for 30 minutes for subsequent processing.
It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim.
Claims (2)
1. The magnesium alloy smelting gas protection device is characterized by comprising a multi-path gas concentration regulation and control system, a gas mixing system and a computer control center;
each path of gas concentration regulating and controlling system comprises a gas storage tank, a pressure regulating valve, a drying tank, a mass flow controller, a gas inlet pipe and an electric control gas valve; the air storage tank, the pressure regulating valve, the drying tank, the mass flow controller, the air inlet pipe and the electric control gas valve are connected in sequence;
the gas mixing system comprises a gas mixing tank, a mixed gas pressure regulating valve and a pressure gauge; the gas mixing tank, the mixed gas pressure regulating valve and the pressure gauge are connected in sequence;
each path of gas concentration regulating and controlling system is connected to a gas mixing tank of the mixed gas through a pipeline by an electric control gas valve;
the computer control center comprises a computer, a power module and a communication module to form a control center, and the control center is respectively and electrically connected with the mass flow controllers and the electric control gas valves of each path of gas concentration regulation and control system, and controls the flow through multipath mass flow controller software in the computer.
2. Use of the magnesium alloy smelting gas protection apparatus of claim 1 in magnesium alloy smelting.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311659583.4A CN117450434A (en) | 2023-12-06 | 2023-12-06 | Magnesium alloy smelting gas protection device and application thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311659583.4A CN117450434A (en) | 2023-12-06 | 2023-12-06 | Magnesium alloy smelting gas protection device and application thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117450434A true CN117450434A (en) | 2024-01-26 |
Family
ID=89587722
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311659583.4A Pending CN117450434A (en) | 2023-12-06 | 2023-12-06 | Magnesium alloy smelting gas protection device and application thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117450434A (en) |
-
2023
- 2023-12-06 CN CN202311659583.4A patent/CN117450434A/en active Pending
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