CN101396726A - Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process - Google Patents
Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process Download PDFInfo
- Publication number
- CN101396726A CN101396726A CNA2008101754532A CN200810175453A CN101396726A CN 101396726 A CN101396726 A CN 101396726A CN A2008101754532 A CNA2008101754532 A CN A2008101754532A CN 200810175453 A CN200810175453 A CN 200810175453A CN 101396726 A CN101396726 A CN 101396726A
- Authority
- CN
- China
- Prior art keywords
- hfc
- nitrogen
- magnesium alloy
- flow
- gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Physical Or Chemical Processes And Apparatus (AREA)
Abstract
The invention provides a fused mass protecting method in the magnesium alloy die-casting process by adopting HFC-134a and nitrogen, and the protective gas consists of the HFC-134a and the nitrogen and protects the fused mass in the magnesium alloy die-casting process. The protective gas and the liquid magnesium alloy are imported into a die cavity at the same time. The concentration of the HFC-134a is controlled at 0.55%-1%, while the concentration of the nitrogen is controlled at 99%-99.45%. The HFC-134a and the nitrogen have the same gas pressure of 0.15MPa-0.75MPa before being imported into the furnace body. The temperature of magnesium alloy melting stock is controlled at 600DEG C-700 DEG C, and the filling rate is controlled at 0.5-10 meters per second. The invention adopts HFC-134a to replace sulfur hexafluoride to protect the fused mass in the magnesium alloy die-casting process, after a protecting film is formed, no more oxidization occurs. The fused mass protecting method can not only protect environment, but also reduce cost, and has obvious economic benefit.
Description
Technical field
The present invention relates to the method for melt protecting in the magnesium alloy pressure-casting process, particularly a kind of HFC-134a of employing mixes the method to melt protecting in the magnesium alloy pressure-casting process with nitrogen.
Background technology
The melt gas that needs protection prevents magnesium burning in the magnesium alloy pressure-casting process; melt protecting gas such as Chinese patent publication number CN1887481A in the advanced magnesium alloy pressure-casting process; name is called: " magnesium alloy liquid controlling device " disclosed technical scheme, adopt sulfur hexafluoride as protective gas.Adopt the shortcoming of sulfur hexafluoride protective gas to be: sulfur hexafluoride is a kind of gas with very serious greenhouse effects; 1 kilogram sulfur hexafluoride is equivalent to the greenhouse effects of 5 tons carbon dioxide generating; serious environment pollution, and the price comparison costliness of sulfur hexafluoride.
Summary of the invention
The objective of the invention is at above-mentioned shortcoming, adopt HFC-134a and nitrogen to replace sulfur hexafluoride, melt in the magnesium alloy pressure-casting process is protected.HFC-134a and nitrogen not only reduce the pollution to environment, and can reduce cost, and obtain obvious social and economic benefit.
The HFC-134a chemical name is a HFC-134a, is called for short HFC-134a or R-134a.It has nontoxic, tasteless, colourless, do not fire, characteristics such as not quick-fried, Heat stability is good.HFC-134a is a kind of HFC that contains, and the bond energy of fluorine carbon bond is very high, thereby general fluorocarbons has better heat endurance and chemical stability.In addition, HFC-134a is nontoxic advantage such as not to fire, thereby does not need special safeguard procedures.In addition, nitrogen also have nontoxic, tasteless, colourless, do not fire, characteristics such as not quick-fried, Heat stability is good.
The object of the present invention is achieved like this:
1, protective gas is made up of HFC-134a and nitrogen, and the technological parameter of HFC-134a and nitrogen is as follows:
(1), the concentration of HFC-134a gas
The concentration of HFC-134a is controlled at 0.55%～1%.The concentration that facts have proved HFC-134a is lower than at 0.55% o'clock, and the effect that melt in the magnesium alloy pressure-casting process is protected is not remarkable.The time that gas arrives liquid level is short more good more, avoids also not contacting HFC-134a with melt and decomposes.
(2), the concentration of nitrogen
The concentration of the concentration of nitrogen is controlled at 99%～99.45%.
(3), the flow of HFC-134a gas
The flow of HFC-134a gas is at the flow of an atmospheric pressure with every square metre of 20ml/min～100ml/min.
(4), the flow of nitrogen
The flow of nitrogen under an atmospheric pressure with the flow of every square metre of 2.5L/min～18L/min.
(5), HFC-134a and nitrogen gas pressure
The pressure of HFC-134a and nitrogen each gas before entering body of heater is 0.15MPa～0.75MPa.HFC-134a is identical with each gas pressure of nitrogen.
2, the improvement of magnesium alloy pressure-casting equipment
(1), increases the HFC-134a gas reservoir
The HFC-134a gas reservoir is equipped with pressure-reducing valve and stainless steel wireway.
(2), increase nitrogen storage tank
Nitrogen storage tank is equipped with pressure-reducing valve and stainless steel wireway.
(3), the improvement of magnesium alloy pressure-casting stove
It is reinforced to need to take off every now and then lid in the magnesium alloy pressure-casting process, and therefore the quality of sealing has certain influence to protection, is lined with the high temperature cotton of protection in magnesium alloy pressure-casting stove sealing lid and body of heater contact site.A wireway is opened on the top of lid, and wireway directly is passed in the middle of the container with alkaline solution, and to remove because of the HF that HFC-134a decomposes and reaction generates, HF has toxicity and corrosivity, can produce certain influence to operating personnel and equipment.Sulfur hexafluoride gas pipe arrangement to original employing carries out the part change, the distance that increases the pipeline number that feeds and suitably reduce mist inlet and liquid level.
3, the technological process of magnesium alloy pressure-casting
Import above-mentioned protective gas to die cavity in the time of magnesium alloy liquid input die cavity.The concentration of HFC-134a is controlled at 0.55%～1%, and the concentration of the concentration of nitrogen is controlled at 99%～99.45%.The flow of HFC-134a gas under an atmospheric pressure with the flow of every square metre of 20ml/min～100ml/min, the flow of nitrogen under an atmospheric pressure with the flow of every square metre of 2.5L/min～18L/min.The pressure of HFC-134a and nitrogen each gas before entering body of heater is 0.15MPa～0.75MPa.HFC-134a is identical with each gas pressure of nitrogen.Control magnesium alloy melt temperature is 600 ℃～700 ℃, and filling speed is 0.5～10 meter per second.Magnesium alloy liquid compression casting moulding.
The present invention adopts the mist of HFC-134a and nitrogen to replace sulfur hexafluoride, and melt in the magnesium alloy pressure-casting process is protected, and forms diaphragm and oxidative phenomena do not occur continuing afterwards.HFC-134a is not only cheap, and molecular weight is less, and the protection environment, can access tangible economic benefit.
The specific embodiment
Below in conjunction with embodiment the present invention is described in further detail:
Embodiment:
Magnesium alloy pressure-casting workshop 200t richness is come machine production
The liquid level area of smelting furnace: 1m
2
Melt temperature: 640 ℃
Pressure and flow before mixing:
Nitrogen: 2 * 10
5Pa (2bar); 1.2L/min
HFC-134a：2×10
5pa(2bar)；0.008L/min
Total flow under atmospheric pressure is about: 1.2 * 2=2.4L/min
Gas concentration: 8/1200=0.67%
Seal approach: adopt high temperature minuteness capping and body of heater, avoid destruction when feeding in raw material as far as possible to sealing device with slag hitting.
The exhaust measure: HFC-134a decomposes and the HF gas of reaction back generation to remove as far as possible to alkali lye to be connected with a wireway on the bell top, prolongs the service life of crucible.
Claims (1)
1, adopt HFC-134a and nitrogen to the method for melt protecting in the magnesium alloy pressure-casting process, it is characterized in that:
A, protective gas are made up of HFC-134a and nitrogen, and the technological parameter of HFC-134a and nitrogen is as follows:
(1), the concentration of HFC-134a gas
The concentration of HFC-134a is controlled at 0.55%～1%;
(2), the concentration of nitrogen
The concentration of nitrogen is controlled at 99%-99.45%;
(3), the flow of HFC-134a
The flow of HFC-134a gas under an atmospheric pressure with the flow of every square metre of 20ml/min～100ml/min;
(4), the flow of nitrogen
The flow of nitrogen under an atmospheric pressure with the flow of every square metre of 2.5L/min～18L/min;
(5), HFC-134a and nitrogen gas pressure
The pressure of HFC-134a and nitrogen each gas before entering body of heater is 0.15MPa～0.75MPa, and HFC-134a is identical with each gas pressure of nitrogen;
B, technological process
Import above-mentioned protective gas to die cavity in the time of magnesium alloy liquid input die cavity; the concentration of HFC-134a is controlled at 0.55%～1%; the concentration of the concentration of nitrogen is controlled at 99%～99.45%; the flow of HFC-134a gas under an atmospheric pressure with the flow of every square metre of 20ml/min～100ml/min; the flow of nitrogen under an atmospheric pressure with the flow of every square metre of 2.5L/min～18L/min; the pressure of HFC-134a and nitrogen each gas before entering body of heater is 0.15MPa～0.75MPa; HFC-134a is identical with each gas pressure of nitrogen; control magnesium alloy melt temperature is 600 ℃～700 ℃; filling speed is 0.5～10 meter per second, magnesium alloy liquid compression casting moulding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008101754532A CN101396726A (en) | 2008-11-07 | 2008-11-07 | Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNA2008101754532A CN101396726A (en) | 2008-11-07 | 2008-11-07 | Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN101396726A true CN101396726A (en) | 2009-04-01 |
Family
ID=40515704
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNA2008101754532A Pending CN101396726A (en) | 2008-11-07 | 2008-11-07 | Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101396726A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103722150A (en) * | 2013-12-30 | 2014-04-16 | 宁夏惠冶科技有限公司 | Magnesium alloy pressure casting integrated controlling and managing method |
| CN104498744A (en) * | 2014-12-17 | 2015-04-08 | 太仓中化环保化工有限公司 | Environment-friendly magnesium alloy smelting protective gas as well as preparation method and application thereof |
| CN106862536A (en) * | 2017-02-19 | 2017-06-20 | 山东银光钰源轻金属精密成型有限公司 | A kind of novel magnesium alloy gas shield new technology |
| CN108251726A (en) * | 2018-02-08 | 2018-07-06 | 山东弗泽瑞金属科技有限公司 | Suitable for the magnesium alloy materials of vacuum low speed pressure casting method |
-
2008
- 2008-11-07 CN CNA2008101754532A patent/CN101396726A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103722150A (en) * | 2013-12-30 | 2014-04-16 | 宁夏惠冶科技有限公司 | Magnesium alloy pressure casting integrated controlling and managing method |
| CN103722150B (en) * | 2013-12-30 | 2015-06-24 | 宁夏惠冶科技有限公司 | Magnesium alloy pressure casting integrated controlling and managing method |
| CN104498744A (en) * | 2014-12-17 | 2015-04-08 | 太仓中化环保化工有限公司 | Environment-friendly magnesium alloy smelting protective gas as well as preparation method and application thereof |
| CN106862536A (en) * | 2017-02-19 | 2017-06-20 | 山东银光钰源轻金属精密成型有限公司 | A kind of novel magnesium alloy gas shield new technology |
| CN108251726A (en) * | 2018-02-08 | 2018-07-06 | 山东弗泽瑞金属科技有限公司 | Suitable for the magnesium alloy materials of vacuum low speed pressure casting method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100354562C (en) | High alloy steel seamless steel pipe and production method thereof | |
| EP2278031B1 (en) | Process for reforming exhaust gas from metallurgical furnace, process for cooling the exhaust gas, and apparatuses for both processes | |
| CN101396726A (en) | Molten metal protection method using HFC-134a and nitrogen gas during magnesium alloy pressure-casting process | |
| CN109234493B (en) | Steelmaking method for stably increasing nitrogen by blowing nitrogen | |
| CN107828938A (en) | A kind of method for preventing the cold steel of RH vacuum circulation degassing process vacuum tanks from bonding | |
| CN106086598A (en) | A kind of high cleanliness austenite is without the smelting process of magnetic Retaining Ring Steel | |
| CN102242275A (en) | Preparation method of silicon-free calcium and iron-containing alloy | |
| CN106319333B (en) | A kind of smelting process of high strength steel v n micro alloying | |
| CN102345047A (en) | 150mm Q245R extra thick plate and production method thereof | |
| CN111961794A (en) | Production method of high-carbon chromium bearing steel small square billet | |
| EP3967670B1 (en) | Method for modifying steelmaking slag | |
| CN105039787A (en) | Explosion-proof type fixed ammonia gas detection probe and manufacturing method thereof | |
| JP2010138446A (en) | METHOD FOR PREVENTING NITROGEN ABSORPTION OF Cr-CONTAINING MOLTEN STEEL | |
| CN103422006B (en) | Boron-containing steel production method for reducing steel ladle lining refractory consumption | |
| MX2014001293A (en) | Method and apparatus for dephosphorising liquid hot metal such as liquid blast furnace iron. | |
| CN103525977A (en) | Dehydrogenation method | |
| CN103160636B (en) | The method of the even molten steel composition of a kind of converter tapping alloying | |
| JP2006283065A (en) | Gas-blowing tuyere | |
| CN201751424U (en) | Molten pool reactor | |
| CN211800680U (en) | Equipment for preparing gallium trichloride | |
| CN211522244U (en) | Improved high manganese steel refining equipment | |
| CN109722502B (en) | Smelting method for preventing boron-containing steel from cracking in web plate of special-shaped blank | |
| CN102808066B (en) | Method for reducing chrome loss by refining ferrochrome with argon and oxygen | |
| CN102382944A (en) | Method for online rapid removal of residual molten steel on bottom blowing core of metallurgical container | |
| CN116288008A (en) | High-purity high-performance nitrogen-containing steel for low-temperature flange and production process thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Open date: 20090401 |