CN1434262A - On-line mixing gas-supply equipment for magnesium alloy smelting protection - Google Patents
On-line mixing gas-supply equipment for magnesium alloy smelting protection Download PDFInfo
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- CN1434262A CN1434262A CN 03119278 CN03119278A CN1434262A CN 1434262 A CN1434262 A CN 1434262A CN 03119278 CN03119278 CN 03119278 CN 03119278 A CN03119278 A CN 03119278A CN 1434262 A CN1434262 A CN 1434262A
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- gas
- pressure
- gas circuit
- mass flow
- controller
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- 238000002156 mixing Methods 0.000 title claims abstract description 30
- 229910000861 Mg alloy Inorganic materials 0.000 title claims abstract description 26
- 238000003723 Smelting Methods 0.000 title claims abstract description 15
- 239000007789 gas Substances 0.000 claims abstract description 108
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 29
- 238000001514 detection method Methods 0.000 claims abstract description 16
- 238000012544 monitoring process Methods 0.000 claims abstract description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 11
- 230000000007 visual effect Effects 0.000 claims description 6
- 229910001873 dinitrogen Inorganic materials 0.000 abstract 2
- 230000001105 regulatory effect Effects 0.000 abstract 2
- 230000001681 protective effect Effects 0.000 description 9
- 238000002844 melting Methods 0.000 description 8
- 230000008018 melting Effects 0.000 description 8
- 238000000034 method Methods 0.000 description 7
- 230000004907 flux Effects 0.000 description 4
- 230000008569 process Effects 0.000 description 4
- 229960000909 sulfur hexafluoride Drugs 0.000 description 4
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 3
- 238000005266 casting Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 239000011777 magnesium Substances 0.000 description 3
- 229910052749 magnesium Inorganic materials 0.000 description 3
- 239000003595 mist Substances 0.000 description 3
- SFZCNBIFKDRMGX-UHFFFAOYSA-N sulfur hexafluoride Chemical compound FS(F)(F)(F)(F)F SFZCNBIFKDRMGX-UHFFFAOYSA-N 0.000 description 3
- 230000008901 benefit Effects 0.000 description 2
- 230000007797 corrosion Effects 0.000 description 2
- 238000005260 corrosion Methods 0.000 description 2
- 230000007812 deficiency Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000008676 import Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000006837 decompression Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000003063 flame retardant Substances 0.000 description 1
- 239000003517 fume Substances 0.000 description 1
- 239000005431 greenhouse gas Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000004321 preservation Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000002893 slag Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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Abstract
The on-line mixed gas-supplying equipment for magnesium alloy smelting protection mainly is formed from two portions of stand-by gas circuit and mixed gas circuit, said mixed gas circuit mainly includes nitrogen gas supply circuit, SF6 gas supply circuit, mixing tank respectively connected with the above-mentioned two gas circuits and output pipeline. In the nitrogen gas supply circuit and 5F6 gas supply circuit the mass flow detection controller, pressure regulating valve and pressure sensor are respectively set, and on the output pipeline of mixing tank the mass flow detection controller and pressure sensor are also set, the above-mentioned detection controllers, pressure sensors and pressure regulating valve are connected with computer monitoring system by means of data signal wire.
Description
Technical field
The utility model relates to a kind of protective gas on-line mixing equipment that is used for magnesium alloy smelting, insulation, belongs to material processing plant
Technical field.
Background technology
Because the special chemical property of magnesium alloy, there are significant difference in magnesium alloy melting and heat preservation system and common alloy melting system.The molten magnesium on magnesium and magnesium alloy surface in fusing, casting process is oxidizing fire very easily, therefore needs the special gas safeguard measure.
Before the seventies; magnesium alloy smelting mainly adopts covering flux protection; though this method can play good fire retardation; but be easy to generate the flux slag inclusion; cause product mechanical property and corrosion resistance to descend; restricted Application of Magnesium, and the corrosive fume of flux and magnesium alloy reaction generation destroys equipment, aggravating working environment.At the initial stage seventies, the exploitation and the application of no flux melting technique cause people's attention.Wherein, protective gas SF
6Application, for the industrial expansion of magnesium alloy significance is arranged.At present, most in the world magnesium alloy pressure-casting factories and part magnesium alloy smelting factory adopt gas protection method melting magnesium alloy, and melting quality and working environment are greatly improved.Existing gas mixer principle is as follows: the SF of higher concentration
6Gas has stronger corrosiveness, SF to the crucible of melting magnesium alloy
6Itself be again a kind of extremely strong greenhouse gases, while SF
6The production cost of gas is also than higher.So SF
6The consumption of gas must seldom experiment showed, in the magnesium-alloy smelting furnace of sealing, adopts the very SF of low concentration
6Gas just can play fire retardation as the protective gas of melting magnesium alloy.At present, usually SF
6Gas is sneaked into N with extremely low concentration (below 0.2%)
2In the gas, utilize SF
6-N
2Mist as the protective gas of melting magnesium alloy.The magnesium alloy smelting process has strict regulation to the flow and the proportioning of hybrid protection gas; gas flow ratio low or sulfur fluoride does not have the effect that stops magnesiaization when low; and crucible is damaged when the too high or too high meeting of sulfur fluoride ratio of mixed gas flow, so it is very important accurately to control the flow that gas mixture ratio example and control mist import in crucible.
At present, the domestic on-line mixing feeder that still is not applied to the magnesium alloy smelting protection, the protection gas feeder of the supporting smelting furnace of magnesium alloy pressure casting machine is all import.The mixing arrangement of the protective gas of each company has nothing in common with each other, but its principle can be divided into two kinds substantially: the one, and no balanced valve gas mixer; The 2nd, the gas mixer of balanced valve is arranged.
The protective gas mixing arrangement of German History Jack (Striko) company is no balanced valve structure, and this structure utilizes two flowmeters to control nitrogen and SF respectively
6Flow, mix output then, because nitrogen use level is much larger than SF
6Consumption, so the pressure of the input of two flowmeters has difference all the time, the flowmeter control accuracy can not be very high, particularly SF
6Amount can not accurately control, often cause the corrosion of crucible.
The protective gas mixing arrangement of Austria labor gram (Rouck) company is for there being the balanced valve structure, and this structure is placed an equilibrated valve before flowmeter, and this valve has the pressure balance function, nitrogen and SF
6When gas passes through this valve simultaneously, if some gas pressure height, this valve will be adjusted this gas inlet and make it to reduce, the last identical two-way gas of output pressure.Because pressure is identical, utilizes flowmeter to carry out flow-control again and mix just than being easier to and accurate.But this gas balance valve belongs to patented product, and price is higher, and this valve is pure frame for movement simultaneously, realizes the gas flow adjusting by spring and rubber membrane, does not have the detection method of safety, can't determine the accuracy of its gas pressure balancing control.
The utility model content
At the deficiencies in the prior art and defective, the purpose of this utility model provides a kind of on-line mixing air feed equipment that is used for the magnesium alloy smelting protection, and this equipment can be realized nitrogen and SF on the one hand
6The accurate control of gas flow and mixed proportion is guaranteed in the accurate mixing of gas, has simple to operately, and the stable and safe and reliable advantage of output can further reduce production costs on the other hand.
The technical solution of the utility model is as follows: a kind of on-line mixing air feed equipment that is used for the magnesium alloy smelting protection, and it mainly is made up of standby gas circuit and mixing gas circuit two parts, and described standby gas circuit mainly comprises N
2-0.18wt%SF
6Mix source of the gas, manual pressure-reducing valve, visual Pressure gauge or visual flowmeter and corresponding pipeline constitute; Described mixing gas circuit mainly comprises nitrogen air feed gas circuit, SF
6Air feed gas circuit and the blending tank and the output pipe that link to each other with two gas circuits respectively is characterized in that: at described nitrogen air feed gas circuit and SF
6Be provided with mass flow in the air feed gas circuit respectively and detect controller and pressure-regulating valve, between described pressure-regulating valve and mass flow detection controller, pressure sensor is housed respectively; Be provided with pressure sensor on blending tank, described output pipe is provided with mass flow and detects controller; Described mass flow detects controller, pressure sensor all links to each other with computer supervisory control system by data signal line with pressure-regulating valve, and this monitoring system is made up of industrial computer and PLC programmable logic controller (PLC).
PCL programmable logic controller (PLC) described in the utility model adopts the SIEMENSPLC that has the PROFIBUS interface.
The utility model compared with prior art has the following advantages and the high-lighting effect: the utility model adopts mass flow to detect controller, pressure sensor and computer control, can make nitrogen and SF
6Each step gas flow and pressure of mixed process all can detect and control, and can detect in real time, quantitatively regulate and feed back according to situation in the stove, guarantee the accurate control of gas flow and mixed proportion, have characteristics such as simple to operate, precise control, stable, the safe and reliable and automaticity height of output.
Description of drawings
Fig. 1 is a magnesium alloy protective gas mixed gas supply schematic diagram of device.
Fig. 2 is the structured flowchart of computer supervisory control system in the utility model.
Fig. 3 is the flow chart of signal controlling.
Among the figure: the standby mixing (N of 1-
2+ 0.18wt%SF
6) source of the gas; The manual pressure-reducing valve of 2-; 3-nitrogen source of the gas; The 4-pressure-regulating valve; 5-sulfur fluoride source of the gas; 6,7-pressure-regulating valve; The standby sulfur fluoride source of the gas of 8-; The 9-computer supervisory control system; 10-pressure-regulating valve (4,6,7) control circuit; The 11-pressure sensor; 12-pressure sensor detection line; The 13-mass flow detects controller; The 14-mass flow detects the control and the detection line of controller (13,23); 15-mixes gas tank pressure detecting signal circuit; The 16-pressure sensor; The 17-check valve; 18-mixes gas tank; The 19-mass flow detects the control and the detection line of controller 20; The 20-mass flow detects controller; The standby manual control gas circuit of 21-; The 22-check valve; The 23-mass flow detects controller; The 24-pressure sensor; The 25-Pressure gauge; The 26-detecting element; The 27-I/O module; The 28-PLC programmable logic controller (PLC); The 29-industrial computer; The 30-executive component.
The specific embodiment
Further specify the concrete structure of the present utility model and the course of work below in conjunction with accompanying drawing.
Fig. 1 is the principle assumption diagram of the magnesium alloy smelting protection on-line mixing feeder embodiment that provides of the utility model.The on-line mixing air feed equipment of magnesium alloy smelting protection mainly comprises standby mixing gas circuit and mixes gas circuit two parts; Standby mixing gas circuit is mainly by 15Mpa (N
2-0.18wt%SF
6) mix source of the gas 1, manually pressure-reducing valve 2, visual Pressure gauge or visual flowmeter 25 and corresponding pipeline constitute; In case when generation has a power failure or the mixed gas supply gas circuit breaks down, can start this standby gas circuit, making has enough protective gas to feed all the time in the crucible, guarantee this system's safe enough.Mix gas circuit and mainly comprise nitrogen air feed gas circuit, SF
6The air feed gas circuit constitutes with blending tank 18 that links to each other with two gas circuits respectively and output gas piping; Comprise mainly that in described nitrogen air feed gas circuit nitrogen source of the gas 3, pressure-regulating valve 4, pressure sensor 24, mass flow detect controller 23, check valve 22 and corresponding pipeline; SF
6The air feed gas circuit mainly comprises SF
6Source of the gas 5, pressure-regulating valve 6, pressure sensor 11, mass flow detect controller 13, check valve 17 and corresponding pipeline; With blending tank 18 that two gas circuits link to each other on be provided with pressure sensor 16, also be provided with mass flow to the gas output tube road of body of heater and detect controller 20 from mixing gas tank.Described pressure sensor 11 links to each other with computer supervisory control system by detection line 12 with 24; Mass flow detects controller 13,23 and links to each other with computer supervisory control system by detection line 14, pressure sensor 16 detects controller 20 with mass flow and links to each other with computer supervisory control system with 19 by data signal line 15 respectively, pressure-regulating valve 4,6 links to each other with computer supervisory control system by control circuit 10 with 7, and this monitoring system is made up of industrial computer 29 and PLC programmable logic controller (PLC) 28.The mass flow of using in the present embodiment detects controller and adopts model to be D07-7A/ZM.
Fig. 2 is the structured flowchart of computer supervisory control system, and this system mainly comprises detecting element 26, I/O module 27, PLC (programmable logic controller (PLC)) 28 and industrial computer 29 and executive component 30; Wherein PLC selects the SIEMENSPLC that has the PROFIBUS interface for use.Detection signal and instruction are handled in PLC and are exported control signal then, and industrial computer is responsible for sending instruction and showing testing result to PLC, realizes the man-machine interface interaction; Detecting element 26 is meant that pressure sensor (11,24,16) in the gas circuit shown in Figure 1 and mass flow detect the detection signal end of controller (13,20,23) among the figure, and executive component 30 is meant the pressure-regulating valve (4,6,7) in this gas circuit and the control signal end of mass flow detection controller (13,20,23).
Fig. 3 is the software flow pattern of signal controlling.The signal controlling of native system is closed-loop control, the control result detects and feeds back in real time PLC by detecting element, PLC is responsible for the setting signal of feedback signal and industrial computer 29 is carried out logic relatively, according to comparative result the control signal of output is carried out the logic adjustment then, realize accurate output control.
The course of work of the present utility model is as follows: as shown in Figure 1, and nitrogen and SF
6All will because gas pressure is very high in the source of the gas, and changing through a decompressor after gas comes out from source of the gas (bottle), can reach 15MPa during high pressure, is 0 during emptying.Mass flow detects controller can not bear so big pressure differential, and this pressure differential also influences flow control accuracy simultaneously.The utility model adopts pressure-regulating valve (4,6,7) and pressure sensor (11,24), and adopts computer monitoring.During work, the COMPUTER DETECTION pressure sensor readings and with setting pressure relatively, if detected pressures is greater than setting pressure, computer will provide order turns down this road pressure-regulating valve, and then further detected pressures, carries out next circularly monitoring, if detected pressures can not reach setting value in setting-up time, computer will provide alarm signal, remind your bleed pressure deficiency, must change; If SF
6Insufficient pressure, system is automatically replaceable to bailout gas.Adopt this technology controlling and process gas to supply with, can accurately control the decompression process of gas, the flow detection of ensuring the quality of products controller front end gas pressure is constant, needn't adopt the mixture pressure balancer.
To detect accurately control gas flow separately of controller by mass flow behind the gas safety relief, and two kinds of gases be entered with preset proportion mix gas tank 18.Mix gas tank 18 and can guarantee that gas fully mixes, if do not establish mixed gas tank, gas can not fully mix, and will influence flame retardant effect.Gas mixes after mass flow controller 20 is input in the crucible.The pressure of mist and output flow detect controller 20 by pressure sensor 16 and mass flow respectively and are monitored in real time by computer system.
Claims (2)
1. one kind is used for the on-line mixing air feed equipment that magnesium alloy smelting is protected, and it mainly is made up of standby gas circuit and mixing gas circuit two parts, and described standby gas circuit mainly comprises N
2-0.18wt%SF
6Mix source of the gas (1), manually pressure-reducing valve (2), visual Pressure gauge or visual flowmeter (25) and corresponding pipeline constitute; Described mixing gas circuit mainly comprises nitrogen air feed gas circuit, SF
6Air feed gas circuit and the blending tank and the output pipe that link to each other with two gas circuits respectively is characterized in that: at described nitrogen air feed gas circuit and SF
6Be provided with mass flow in the air feed gas circuit respectively and detect controller (23), (13) and pressure-regulating valve (4), (6), between described pressure-regulating valve and mass flow detection controller, pressure sensor (24), (11) are housed respectively; Be provided with pressure sensor (16) on blending tank (18), described output pipe is provided with mass flow and detects controller (20); Described mass flow detects controller, pressure sensor all links to each other with computer supervisory control system by data signal line with pressure-regulating valve, and this monitoring system is made up of industrial computer (29) and PLC programmable logic controller (PLC) (28).
2. according to the described on-line mixing air feed equipment of claim 1, it is characterized in that: described PLC programmable logic controller (PLC) adopts the SIEMENSPLC that has the PROFIBUS interface.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031192785A CN1322298C (en) | 2003-03-07 | 2003-03-07 | On-line mixing gas-supply equipment for magnesium alloy smelting protection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB031192785A CN1322298C (en) | 2003-03-07 | 2003-03-07 | On-line mixing gas-supply equipment for magnesium alloy smelting protection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1434262A true CN1434262A (en) | 2003-08-06 |
| CN1322298C CN1322298C (en) | 2007-06-20 |
Family
ID=27634508
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB031192785A Expired - Fee Related CN1322298C (en) | 2003-03-07 | 2003-03-07 | On-line mixing gas-supply equipment for magnesium alloy smelting protection |
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| CN (1) | CN1322298C (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101685056B (en) * | 2009-03-25 | 2011-10-26 | 河南科技大学 | Method and device for controlling accurate ratio of various gas atmospheres of frictional wear testing machine |
| CN101470050B (en) * | 2007-12-29 | 2012-10-31 | 北京谊安医疗系统股份有限公司 | Integrated measuring instrument |
| CN102912180A (en) * | 2012-10-25 | 2013-02-06 | 无锡中彩新材料股份有限公司 | Metallurgical proportional valve |
| CN104329943A (en) * | 2014-09-23 | 2015-02-04 | 北京首钢股份有限公司 | Leakage detection method for automatic cut-off valve and RH circulation air valve device |
| CN107908202A (en) * | 2017-10-27 | 2018-04-13 | 中冶华天南京电气工程技术有限公司 | A kind of AOD furnace cross air blasting gun pipe ring stitches flow control methods |
| CN109173759A (en) * | 2018-09-06 | 2019-01-11 | 久天智能装备有限公司 | A kind of gas mixer suitable for laser cutting |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102168918A (en) * | 2011-03-31 | 2011-08-31 | 株洲火炬工业炉有限责任公司 | Power frequency cored induction electric furnace and method for controlling oxygen content |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2423553Y (en) * | 2000-05-10 | 2001-03-14 | 郭吉成 | Semi-automatic-controlled hot-circulation device for roast oven |
| CN2606873Y (en) * | 2003-03-07 | 2004-03-17 | 清华大学 | On-line mixing gas supply device for magnesium alloy smelting protection |
-
2003
- 2003-03-07 CN CNB031192785A patent/CN1322298C/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101470050B (en) * | 2007-12-29 | 2012-10-31 | 北京谊安医疗系统股份有限公司 | Integrated measuring instrument |
| CN101685056B (en) * | 2009-03-25 | 2011-10-26 | 河南科技大学 | Method and device for controlling accurate ratio of various gas atmospheres of frictional wear testing machine |
| CN102912180A (en) * | 2012-10-25 | 2013-02-06 | 无锡中彩新材料股份有限公司 | Metallurgical proportional valve |
| CN104329943A (en) * | 2014-09-23 | 2015-02-04 | 北京首钢股份有限公司 | Leakage detection method for automatic cut-off valve and RH circulation air valve device |
| CN104329943B (en) * | 2014-09-23 | 2016-06-29 | 北京首钢股份有限公司 | The leakage detection method of a kind of automatic stop valve and RH circulating air valve gear |
| CN107908202A (en) * | 2017-10-27 | 2018-04-13 | 中冶华天南京电气工程技术有限公司 | A kind of AOD furnace cross air blasting gun pipe ring stitches flow control methods |
| CN109173759A (en) * | 2018-09-06 | 2019-01-11 | 久天智能装备有限公司 | A kind of gas mixer suitable for laser cutting |
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| Publication number | Publication date |
|---|---|
| CN1322298C (en) | 2007-06-20 |
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