CN102728815B - Vacuum self-gravity pouring high-static pressure strong-pouring die-casting forming equipment and technique thereof - Google Patents
Vacuum self-gravity pouring high-static pressure strong-pouring die-casting forming equipment and technique thereof Download PDFInfo
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- CN102728815B CN102728815B CN201210258250.6A CN201210258250A CN102728815B CN 102728815 B CN102728815 B CN 102728815B CN 201210258250 A CN201210258250 A CN 201210258250A CN 102728815 B CN102728815 B CN 102728815B
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Abstract
The invention relates to vacuum self-gravity pouring high-static pressure strong-pouring die-casting forming equipment and technology thereof, and the device comprises an aluminum melting furnace, wherein the aluminum melting furnace is connected with a holding furnace, a switch valve is arranged on a connecting pipe, the holding furnace is connected with the side part of the lower end of a charging barrel by a conveying pipe, an oil cylinder is arranged above the charging barrel and drives a charging barrel piston to run vertically in the charging barrel, a charging barrel feed inlet is positioned in the running stroke of the charging barrel piston, the charging barrel is positioned above a mold tooling assembly, a molten aluminum pouring runner communicated with a charging barrel discharge outlet is arranged in the mold tooling assembly and communicated with a mold cavity, the inner chamber and a casting head of the mold cavity are communicated with a vacuum pipe by a slit type vacuumizing channel, the vacuum pipe is connected to a vacuum buffer tank which is connected with a vacuum pump. The equipment and technique can ensure that the formed workpiece not only has excellent vacuum-cast mechanical properties, but also has good high-pressure-cast surface properties.
Description
Technical field
The present invention relates to a kind of vacuum deadweight high static pressure casting forming equipment of cast and technique thereof.
Background technology
In the existing shaping to aluminium and aluminium workpiece of China, all adopt cast and two kinds of techniques of die casting, all there is to some extent pore in the inside workpiece of two kinds of forming technologies.When die casting, because material is spurting and enters fast in mold cavity, have little time gas and the aluminium oxide of discharge, form pore and inside workpiece tissue and change, cause die casting mechanical performance to have defect.When cast, material does not form spurting but has pore yet and produces, cast workpiece better mechanical property, but the special workpiece of the working surface that is not easy to have formed, particularly some shapes is difficult for being shaped.
At present, all have both at home and abroad in investigation for the pore problem of inside workpiece, also have in research both at home and abroad and inquire into for evacuated die-casting process.There is student's thesis discussion in the Central China University of Science and Technology but does not enter practicality, and what it adopted is to utilize vacuum that material is sucked to then injection of barrel.But the deadweight of the necessary expending equilibrium material of pull of vacuum, once just suction again in balance also has material how to carry and stop carrying, all there is the difficulty of implementation process in these technical problems.Single die casting cannot effectively improve the mechanical performance of die casting, just reduces the formation of internal porosity.
All having the relevant report of vacuum die casting machine in the Wuhan Central China University of Science and Technology of Japan, Germany and China, is all to adopt high-temperature material to spray die casting, is difficult for realizing good workpiece mechanical performance, mainly contains three kinds of following methods.
The one, German Vacural method, will melt aluminium stove and directly be connected with injection chamber by stalk, only liquation will be drawn in injection chamber with the mode of vacuumizing, and then continue die cavity to be evacuated down to injection shaping again after predetermined value.But this process must be closed charging aperture, not so the drop potential energy of barrel and stove liquid level can reduce the vacuum in die cavity.
The 2nd, German MFT method, it is divided into 4 steps: 1. barrel is carried out to quantitative pouring material, 2. injection chamber piston makes the air natural in injection chamber discharge to die cavity top to material slow shot, then rapid vacuumizing, 3. when injection chamber piston forward be advanced to feed occupy injection chamber space 1/3 ~ 1/2 time, close immediately to vacuumize and realize quick injection, 4. injection is complete realizes pressurize and Liu Mo is cooling; The method is to adopt quantitative mechanism charging type for the material feeding of barrel, or adopts artificial batcher charging process; 2. step is to utilize vacuum energy-absorbing tank energy-absorbing principle, just realize behaviour's vacuum fast when opening vacuum valve, in the time of Design of Dies, adopt large cast gate to make liquation enter fast die cavity, energy source is now in two aspects simultaneously: the one, and pull of vacuum, the 2nd, the propulsive force of cartridge piston.
The 3rd, Dary, Switzerland side vacuum die casting machine, its operation principle and German MFT method are basic identical, are all to adopt barrel to be placed in mold cavity below, above mould, arrange and vacuumize, first to barrel injection chamber dosing then slow shot vacuumize, proceed to fast shot after closing vacuum valve.No matter the prior art cited several evacuated die-casting process modes that are common die casting or above correlation data, the surface quality of its workpiece is all that quick injection impulsive force and the pressure that pressured casting machine is implemented the charging later stage to mold cavity is realized.Although this method has good workpiece surface quality, thereby be shaping crystallization and the mechanical performance that spurting charging affects final workpiece because quick injection causes material.
Summary of the invention
In view of the deficiencies in the prior art, the object of the present invention is to provide a kind of vacuum deadweight high static pressure casting forming equipment of cast and technique thereof simultaneously with the excellent mechanical properties of vacuum casting and the excellent surface performance of Hpdc.
To achieve these goals, technical scheme one of the present invention is: the high static pressure casting forming equipment of a kind of vacuum deadweight cast, comprise molten aluminium stove, holding furnace, barrel, cartridge piston, oil cylinder, mold tooling sub-assembly, vacuum buffer tank and vavuum pump, described molten aluminium stove be connected with holding furnace and tube connector on be provided with keying valve, described holding furnace is connected with the lower end sidepiece of barrel through conveying pipeline, described oil cylinder is arranged at barrel top and drives cartridge piston operation up and down in barrel, described barrel charging aperture is positioned among cartridge piston operation stroke, described barrel is positioned at the top of mold tooling sub-assembly, in described mold tooling sub-assembly, be provided with the aluminium liquid cast runner being connected with barrel discharging opening, described aluminium liquid cast runner is connected with mold cavity, the interior chamber of described mold cavity is connected with vacuum pipe through slit evacuation passageway with watering to begin to crop up, described vacuum pipe is connected to vacuum buffer tank, described vacuum buffer tank is connected with vavuum pump.
Further, the upper liquid level in described holding furnace is high compared with mold cavity liquation contact-making surface.
Further, described holding furnace is connected with in air compressor machine and connecting pipe and is provided with air intake valve, and described holding furnace is provided with Pressure gauge, venting valve and safety valve.
Further, described conveying pipeline is provided with conveying pipeline heater near on a section of barrel charging aperture.
Further, the cross-sectional area of described oil cylinder is large compared with the cross-sectional area of barrel.
Further, the position that contacts with cartridge piston bar, the upper end of described barrel is provided with seal.
Further, on described cartridge piston bar, be provided with to the cooling water inlet/outlet pipe of logical cooling water in bar.
Further, described slit evacuation passageway is flat channel, and its flat port height is 0.15 ~ 0.25mm.
Further, the top of described molten aluminium stove is provided with material preheating zone.
Further, the below of described mold tooling sub-assembly is provided with mould downlink working point and separates preheating zone with two die workpieces.
To achieve these goals, technical scheme two of the present invention is: the high static pressure casting forming technique of a kind of vacuum deadweight cast, adopt the above-mentioned high static pressure casting forming equipment of vacuum deadweight cast, carry out according to the following steps: (1) is put into molten aluminium stove by preheated aluminium ingot and carried out overheated melting, and setting the overtemperature melting is 680～800 DEG C; (2) the aluminium liquid after melting enters holding furnace and is incubated by opening and closing valve, and the temperature of insulation is controlled between 670 ~ 780 DEG C; (3) mold tooling sub-assembly and barrel are connected to a fixed, when initial, cartridge piston is positioned at the bottom of barrel and blocks barrel charging aperture, unlatching vacuum valve, startup vavuum pump make the interior air of mold cavity and barrel below air vacuumize through vacuum pipe, make mold cavity and barrel all in vacuum state; (4) in vacuumizing, cylinder putter upwards moves and drives cartridge piston to up, in the time that up stroke exceedes barrel charging aperture top, stop up, now holding furnace is connected with barrel by conveying pipeline, and aluminium liquid is realized and entered barrel and mold cavity from holding furnace Quick pouring under the effect of vacuum and the deadweight of aluminium liquid; (5) in the time that aluminium liquid fills to cartridge piston downside, cylinder putter moves downwards and drives cartridge piston operation downwards to make excessive aluminium liquid automatically return to holding furnace through barrel charging aperture, in the time that exceeding barrel charging aperture below, cartridge piston operation downwards just automatically closes barrel charging aperture and then self-assembling formation quantitative feeding, now realize cartridge piston the workpiece cartridge piston that pressurizes is then continued operation downwards and realizes workpiece is applied to high static pressure to realize pressurize, in pressurize, carry out cooling to workpiece; (6) after the cooling rear certain hour of pressurize, dwell time is controlled at 1 ~ 15 second, stays mould to be controlled at 5 ~ 30 seconds cool time, and cylinder putter moves downwards, mold tooling sub-assembly is operation downwards simultaneously, and the stub bar in barrel enters mould downlink working point in company with mould separating barrel; (7), under mechanism, mould separates preheating zone with workpiece translational motion to die workpiece, carries out workpiece demoulding processing; (8) separate behind preheating zone when mould enters above-mentioned die workpiece, be positioned at another die workpiece separate preheating zone the mould of heat treated enter mould downlink working point and rise and barrel combination simultaneously, cartridge piston return carries out lower whorl work.
Further, in step (4), the conveying pipeline that molten aluminium stove is connected with barrel is provided with conveying pipeline heater near on a section of barrel charging aperture, makes the plane layer liquation of barrel charging aperture and cartridge piston contact-making surface keep mobile.
Further, in step (4), when need to increase the feeding of deadweight vacuum pouring process material compared with complex part and particular/special requirement workpiece and the pressure of mold cavity Contact material to cavity surface, first pour pressed gas with pressurization to airtight holding furnace, aluminium liquid is finally realized and is entered barrel and mold cavity from holding furnace Quick pouring under the effect of vacuum, the deadweight of aluminium liquid and pressure.
Further, in step (7) and (8), two die workpieces separate preheating zone and are provided with mould and die preheating device.
The poly-vacuum deadweight of the present invention cast is configured as one with high pressure pressurize, and it has the following advantages.
One, adopt vacuum die cavity to make workpiece effectively solve type cavity gas in forming process and enter the problem in workpiece body.
Two, adopt vacuum deadweight cast to make to pour into a mould liquation and enter the quickening of die cavity flow velocity, can improve to a certain extent the mechanical performance of pouring piece, experimental results show that the pouring piece mechanical performance in the time that cast liquation reaches 20m/s is relatively good.Simultaneously, workpiece is shaped with low-pressure casting and Hpdc is shaped compares, the workpiece comprehensive mechanical intensity that the workpiece that low-pressure casting is shaped is shaped than high pressure pressure injection is good, thereby do not adopt Hpdc to be shaped for a lot of particular/special requirement workpiece, and adopt low-pressure casting to be shaped, such as adopting low-pressure casting exactly, automotive hub is shaped.Employing vacuum deadweight castable, because flow velocity improves, has not only improved the mechanical performance of cast workpiece, and has effectively reduced the internal porosity of drip molding, has improved widely the rear workpiece quality of cast.Adopt isostructure to adopt respectively deadweight vacuum pouring and common die casting contrast with material with profile workpiece through experiment, its tensile strength can improve 20.3%, percentage elongation can improve 83.1%, the raising of toughness and flexing resistance is very obvious, anti-bending strength is enhanced about more than once, and appearance performance visually observes as broad as long.
Three, adopt the vacuum deadweight castable extrusion process of first vacuum deadweight cast, rear high pressure pressurize, ensure the excellent mechanical properties of the existing vacuum casting of Forming Workpiece, the excellent surface performance that has again Hpdc, is specially adapted to the low-melting alloys such as low melting point metal material and aluminium alloy, metal, magnesium alloy.
Four, the vacuum deadweight castable extrusion process that adopts first vacuum deadweight cast, rear high pressure pressurize, easily realizes large exert pressure pressurize.Because charging of the present invention relies on vacuum, deadweight and potential energy and liquation pressure to realize completely, pressurization pressurize is below mainly to improve supplementary that workpiece surface quality and the special position filling to special-shaped face and cooling procedure workpiece shrink, and also liquation is increased to static pressure simultaneously.But the method is different from existing die casting machine, if the large die casting of prior art workpiece special-shaped, quality of material must adopt great tonnage hydraulic system, because must have enough barrel area, volume and pressure to ensure Quick-forming and the pressurization of workpiece.And the present invention is according to formula S 1 × F1=S2 × F2, employing equipment arranges that oil cylinder working-pressure is little, oil cylinder area is large and the little way of barrel area realizes the large exert pressure of barrel work, because the pressure transmission of liquid is with identical at the transmission of pressure of unit square area, thereby realize the pressurization pressurize object of the large pressure of little driving.Key is without large pressure injection amount in the pressurization pressurize course of work in later stage, only demand compressive load per unit area, from compression motion to pressurize course of action, the operation stroke of cartridge piston is very short, only need meet the required material amount of filling up of shrinkage workpiece and surface aesthetic and the needed stopping of compactness of inside workpiece structure.
Brief description of the drawings
Fig. 1 is the organigram of the embodiment of the present invention.
Fig. 2 is the organigram of holding furnace.
Fig. 3 is that mould and barrel vacuumize schematic diagram.
Fig. 4 is mould and barrel charging schematic diagram.
Fig. 5 is mould and the unnecessary feed liquid backflow of barrel schematic diagram.
Fig. 6 is that cartridge piston is to mould and barrel feed liquid pressurization schematic diagram.
Fig. 7 is that cartridge piston is to mould and barrel feed liquid pressurize schematic diagram.
In figure: 1-melts aluminium stove, 2-opens and closes valve, 3-holding furnace, 4-conveying pipeline heater, 5-barrel, 6-cartridge piston, 7-oil cylinder, 8-mold tooling sub-assembly, 9-vacuum pipe, 10-vacuum valve, 11-vacuum buffer tank, 12-vavuum pump, 13-conveying pipeline, 14-aluminium liquid cast runner, 15-waters and begins to crop up, 16-slit evacuation passageway, 17-air intake valve, 18-Pressure gauge, the 19-valve of exitting, 20-safety valve, 21-air compressor machine, 22-seal, 23-cooling water inlet/outlet pipe, A-mould downlink working point, B, C-die workpiece separates preheating zone, D-material preheating zone.
Detailed description of the invention
Below in conjunction with drawings and Examples, the present invention is further elaborated.
With reference to figure 1 ~ 2, the high static pressure casting forming equipment of a kind of vacuum deadweight cast, comprise molten aluminium stove 1, holding furnace 3, barrel 5, cartridge piston 6, oil cylinder 7, mold tooling sub-assembly 8, vacuum buffer tank 11 and vavuum pump 12, described molten aluminium stove 1 be connected with holding furnace 3 and tube connector on be provided with open and close valve 2, described holding furnace 3 is connected with the lower end sidepiece of barrel 5 through conveying pipeline 13, described oil cylinder 7 is arranged at barrel 5 tops and drives cartridge piston 6 in the interior operation up and down of barrel 5, described barrel 5 charging apertures are positioned at cartridge piston 6 and move among stroke, described barrel 5 is positioned at the top of mold tooling sub-assembly 8, in described mold tooling sub-assembly 8, be provided with the aluminium liquid cast runner 14 being connected with barrel 5 discharging openings, described aluminium liquid cast runner 14 is connected with mold cavity, begin to crop up and 15 be connected with vacuum pipe 9 through slit evacuation passageway 16 in the interior chamber of described mold cavity and watering, described vacuum pipe 9 is connected to vacuum buffer tank 11, described vacuum buffer tank 11 is connected with vavuum pump 12.
In the present embodiment, described holding furnace 3 is connected with and in air compressor machine 21 and connecting pipe, is provided with air intake valve 17, described holding furnace 3 is provided with Pressure gauge 18, venting valve 19 and safety valve 20, can be first to airtight holding furnace 3 pour pressed gas with pressurization when increasing the feeding of deadweight vacuum pouring process material with the pressure of mold cavity Contact material to cavity surface, satisfied with the cast of complex part and particular/special requirement workpiece.
In the present embodiment, described conveying pipeline 13 is provided with conveying pipeline heater 4 near on a section of barrel 5 charging apertures, to ensure the mobility of barrel 5 charging apertures and cartridge piston 6 contact-making surface plane layer solution, namely ensure technological temperature, should notice that material stream passed must be unobstructed.
In the present embodiment, the cross-sectional area of described oil cylinder 7 is large compared with the cross-sectional area of barrel 5.According to the inverse relation of oil cylinder 7 cross-sectional areas and barrel 5 cross-sectional areas (S) and pressure (F) (oil cylinder piston S1/ cartridge piston S2=barrel F2/ oil cylinder F1), adopt major diameter oil cylinder, minor diameter barrel, barrel pressure be can in Same Efficieney situation, improve, large pressure pressurize and pressurization are easy to realize.
In the present embodiment, the whole vacuum of the present invention closed-loop path is easy to control condition of high vacuum degree, and the position that contacts with cartridge piston bar, the upper end of described barrel 5 is provided with seal 22, to ensure the vacuum of system works.On described cartridge piston bar, be provided with to the cooling water inlet/outlet pipe 23 of logical cooling water in bar, to ensure the normal work of equipment.The present invention, because charging is to adopt vacuum deadweight method, without relying on cartridge piston 6 to advance feed, therefore can be lubricated cartridge piston 6, can effectively reduce workpiece because of the lubricated gas producing.
In the present embodiment, described slit type vacuum passage 16 is flat channel, and its flat port height is 0.15 ~ 0.25mm, to make the slit type vacuum passage 16 can only circulated gases and the liquation and must be easy to cleaning of can not circulating.
In the present embodiment, the top of described molten aluminium stove 1 is provided with material preheating zone D; The below of described mold tooling sub-assembly 8 is provided with mould downlink working point A and separates preheating zone B, C with two die workpieces.
With reference to figure 1 ~ 7, the high static pressure casting forming technique of a kind of vacuum deadweight cast, carries out according to the following steps.
(1) preheated aluminium ingot is put into molten aluminium stove 1 and carried out overheated melting, the fusion temp of aluminium is 660.4 DEG C, and setting the overtemperature melting is 680～800 DEG C; But while melting, must be noted that the overtemperature melting is unsuitable too high, should determine according to the condition such as practical work piece, technique.Overheated liquation absorbs airborne aqueous vapor in fusion processes makes it to resolve into H
2and O
2, will make like this H in aqueous vapor
2enter in aluminum melt, and hydrogen content in aluminum melt is to rise along with the rising of temperature.The hydrogen that the aluminum melt of every 100g contains 10ml in the time of 700 DEG C, rise to 30ml, but this is reversible in the time of 900 DEG C, and while dropping to 700 DEG C as the aluminum melt of 900 DEG C, the content of hydrogen just drops to 10ml/100g from 30ml/100g.
(2) the aluminium liquid after melting enters holding furnace 3 and is incubated by opening and closing valve 2, the temperature of insulation is depending on the process conditions of its workpiece, complex structure, the suitably height of workpiece temperature that workpiece charge level is thin, workpiece temperature simple in structure, workpiece material road is large should be controlled less, and the temperature of insulation is controlled between 670 ~ 780 DEG C in principle.
(3) mold tooling sub-assembly 8 and barrel 5 are connected to a fixed, when initial, cartridge piston 6 is positioned at the bottom of barrel 5 and blocks barrel 5 charging apertures, unlatching vacuum valve 10, startup vavuum pump 12 make the interior air of mold cavity and barrel below air vacuumize through vacuum pipe 9, make mold cavity and barrel 5 all in vacuum state; But having a technical problem in this process is exactly the processing of the suction mouth of mould, the slit type vacuum passage 16 of mould must be can only circulated gases and the liquation and must be easy to cleaning of can not circulating.Solution is that slit type vacuum passage 16 adopts flat channel, general control passage flat port height is between 0.15mm ~ 0.25mm, width and length are determined according to practical work piece and process condition, can stop liquation to enter slit type vacuum passage 16, the surface tension of molten metal is large, along with the surface variations tension force of temperature has significant change, can stop liquation to enter slit type vacuum passage 16 by the method for adjusting melt temperature and flat port height.
(4) in vacuumizing, oil cylinder 7 push rods upwards move and drive cartridge piston 6 to up, in the time that up stroke exceedes barrel 5 charging aperture top, stop up, now holding furnace 3 is connected with barrel 5 by conveying pipeline 13, and aluminium liquid is realized and entered barrel 5 and mold cavity from holding furnace 3 Quick pourings under the effect of vacuum and the deadweight of aluminium liquid.
In force, the conveying pipeline 13 that molten aluminium stove 1 is connected with barrel 5 is provided with conveying pipeline heater 4 near on a section of barrel 5 charging apertures, to ensure the mobility of barrel 5 charging apertures and cartridge piston 6 contact-making surface plane layer solution, namely ensure technological temperature, should notice that material stream passed must be unobstructed.
(5) in the time that aluminium liquid fills to cartridge piston 6 downside, oil cylinder 7 push rods move downwards and drive cartridge piston 6 operation downwards to make excessive aluminium liquid automatically return to holding furnace 3 through barrel 5 charging apertures, in the time that exceeding barrel 5 charging aperture below, cartridge piston 6 operation downwards just automatically closes barrel 5 charging apertures and then self-assembling formation quantitative feeding, now realizing cartridge piston 6 continues operation downwards and realizes workpiece is applied to high static pressure to realize pressurize the workpiece cartridge piston 6 that pressurizes then, in pressurize, carry out cooling to workpiece, cooling cooling two kinds of the cooling and medium of nature that is divided into, naturally cooling is that pattern tool self heat is conducted cooling that distribute heat carries out, medium is cooling to be imported cooling medium exactly and forces cooling in mould.
In force, when need to increase the feeding of deadweight vacuum pouring process material compared with complex part and particular/special requirement workpiece and the pressure of mold cavity Contact material to cavity surface, can in step (4), adopt the method that sealed thermal insulating stove 3 is poured to pressed gas, concrete unit's area pressurization value is determined according to technique, can set pressurization > 12kg/cm
2scope is adjusted, and aluminium liquid is finally realized and entered barrel and mold cavity from holding furnace Quick pouring under the effect of vacuum, the deadweight of aluminium liquid and pressure.
According to the inverse relation of oil cylinder 7 cross-sectional areas and barrel 5 cross-sectional areas (S) and pressure (F) (oil cylinder piston S1/ cartridge piston S2=barrel F2/ oil cylinder F1), adopt major diameter oil cylinder, minor diameter barrel, barrel pressure be can in Same Efficieney situation, improve, large pressure pressurize and pressurization are easy to realize.Because after vacuum pouring, in mold cavity and barrel 5, be full of solution.Last pressurization and pressurize are the surface state in order to change cast workpiece and prevent that workpiece from producing contraction and gauffer, cold shut, shrinkage cavity, owing the incomplete class defects such as casting.
(6) after the cooling rear certain hour of pressurize, the concrete time is depending on workpiece size structure complexity, the general dwell time is controlled at 1 ~ 15 second, stay mould to be controlled at 5 ~ 30 seconds cool time, oil cylinder 7 push rods move downwards, mold tooling sub-assembly 8 is operation downwards simultaneously, and the stub bar in barrel 5 enters mould downlink working point A in company with mould separating barrel 5.
(7) under mechanism, mould separates preheating zone B and carries out workpiece demoulding processing with workpiece translational motion to die workpiece, and workpiece demoulding processing comprises separating of the separating of mould and workpiece, stub bar and workpiece.
(8) separate after the B of preheating zone when mould enters above-mentioned die workpiece, be positioned at another die workpiece separate preheating zone C the mould of heat treated enter that mould downlink working point A rises simultaneously and barrel 5 combinations, cartridge piston 6 returns carry out lower whorl work; Two die workpieces separate preheating zone B, C and are provided with mould and die preheating device.
In the invention process process, a technical essential is exactly to adopt in deadweight casting process to ensure that liquation enters die cavity and the pressure of die cavity contact-making surface moment liquation to surface of mould cavity.
Common cast liquation comes from and waters the proportion of open height, liquation and the cast impulse force of liquation the moment pressure of wall, because it is limited that open height is watered in this cast, liquation enters that die cavity will overcome runner friction and the melt temperature decline surface tension speed that causes due to mould and the liquation temperature difference increases, mobility reduces, also just increase friction, so common cast liquation enters die cavity and die surface contact-making surface moment pressure > 0.5kg/cm
2; If in the situation that not considering the inner friction of die cavity, in the time that being 1.3 meters of height, material open height produces 0.5kg/cm
2pressure.
And of the present invention be the high-order channel process cast of deadweight vacuum, the pressure that liquation enters die cavity contact-making surface moment comes from the vacuum of die cavity, pressure on liquation deadweight and holding furnace in the discrepancy in elevation and the holding furnace of liquid level and mould liquid moment contact-making surface (also tackling the airtight holding furnace gas of exerting pressure for complex part) die cavity vacuum, the mobility (stove liquid temp is the key index that affects mobility) of liquation proportion and liquation, liquation the flow through flow velocity of mould gate and the pressure of liquation and mould moment contact-making surface are determined, be actually a kind of kinetic energy impulsive force being transformed by potential energy, and this potential energy is by proportion, the discrepancy in elevation, in holding furnace, pressure and vacuum determine.
Taking liquid level on holding furnace and the mold cavity liquation contact-making surface discrepancy in elevation as 2.6 meters of settings, in the frictional force situation of not considering mold runner and die surface, be as the criterion with 0.9 negative-pressure vacuum degree, the pressure of liquation and mold cavity contact-making surface is 1.9kg/cm
2; If be (1.9+3)=4.9kg/cm to applying the pressure of 3kg in holding furnace
2, in concrete stove, pressurization value is taking workpiece, technological requirement as cold.This technique is actually a kind of form of potential energy to kinetic transformation, for same liquation final decision pressure is the pressure in the temperature difference and the holding furnace of height, mobility vacuum and mould and liquation, can take to improve the preheat temperature of mould for some complex structure parts, heighten the way of exerting pressure in the height holding furnace of holding furnace with respect to mould, the difference of height of the high-order holding furnace of the present invention is adjustable.
In implementation process, finish moment in the cast of conducting oneself with dignity and implement immediately pressurization, pressurize, should under the process conditions of 640 DEG C of die cavity inner melt temperature >, implement, the adjustment in specific implementation process corresponds to the technological requirement of workpiece and adjusts the preheat temperature of mould and the holding temperature of holding furnace liquation.
It is limited only adopting the height of the high-order holding furnace groove of deadweight vacuum pouring method, if the pressure that actual liquation in the course of the work and die cavity contact-making surface moment function produce can not meet good surface property requirement, also can't resolve the problem that workpiece shrinks, fills up, die casting produces large pressure 100 ~ 300kg/cm
2, thereby can form good surface, can prevent the problems such as shrinkage cavity contraction simultaneously.The present invention takes to impose 100 ~ 300kg/ cm after casting complete
2pressure, simultaneously pressurize 1 ~ 15 second, stays mould cooling 5 ~ 30 seconds, so just can ensure that workpiece has good outer surface and good mechanical performance.
The present invention in implementation process for some structures compared with complex part in deadweight vacuum pouring process because the large workpiece material of mould ingate resistance at ingate easily by mold cools down, can cause the kinetic energy pressure of material and mould moment contact-making surface decline and can not meet technological requirement, the way of depending adjustment holding furnace height under this situation alone is to realize technological requirement, should adopt airtight holding furnace pressed gas in addition, can be at > 12kg/cm
2scope in pressurize according to process conditions, can effectively improve like this deadweight vacuum pouring speed and the kinetic energy pressure of material and mould moment, it increases force value corresponding to holding furnace pressure air pressurization value.As shown in Figure 2: first opening air intake valve 17, is definite value 0 ~ 12kg/cm to holding furnace 3 plus-pressure air
2, in the time that material is the next to holding furnace 3, open venting valve 19, be then fed to holding furnace 3 liquid level high positions by molten aluminium stove 1 and stop charging.
The present invention is process self-quantitatively to materials quantitative in deadweight vacuum pouring process, because die cavity and barrel are vacuumizing position.When Fig. 3 state, barrel 5 and die cavity are vacuumized; In the time entering Fig. 4 state, realize automatic casting, owing to applying pressure in pull of vacuum+material deadweight+liquid level and mold cavity position difference in height potential energy+holding furnace, now the material in holding furnace 3 will be realized autofeed by barrel 5 charging apertures, and be full of all spaces that vacuumize below cartridge piston 6 lower planes, comprise that mold cavity space realizes the course of work self-quantitatively.
The present invention, in liquation course of conveying, is to carry out in a vacuum, the liquid discord air contact after fusing.Molten aluminium stove 1 or the holding furnace liquation upper epidermis after melting completely forms oxide layer, can effectively stop liquation after fusing, to absorb hydrogen again; Also can adopt the way that is filled with inert gas at airtight molten aluminium stove 1 and sealed thermal insulating stove, reduce the hydrogen content (gas in liquation is mainly hydrogen, and content accounts for 80 ~ 90%) in liquation.
The present invention enters the open and close controlling of vacuum die cavity and barrel process at liquation, moving and realizing up and down by cartridge piston.The present invention is different from existing vacuum die casting machine, vacuumizes and is not arranged on before high-speed casting, pours into a mould in the whole process of carrying out and be arranged on; Existing die casting machine is pressed piston because of the note of barrel and is moved fast, and must adopt lubricant to be lubricated.In the time vacuumizing, cartridge piston 6, in the time of position shown in Fig. 3, is closed barrel 5 charging apertures and is vacuumized work.In the time reaching 0.9 large high pressure of vacuum, cartridge piston 6 upwards moves to the position shown in Fig. 4, now realizes vacuum deadweight cast, and material fills up die cavity and barrel 5 lower space.When in position shown in Fig. 5, cartridge piston 6 moves downwards, there is the anti-holding furnace 3 that overflows back of part material in barrel 5 bottoms, in the time that going downwards to the position shown in Fig. 6, realizes cartridge piston 6 pressurization, due to the effect of pressure, cartridge piston 6 can continue down to the position shown in Fig. 7, and the oil pump of now working is realized low rotation speed large torque work, and cartridge piston 6 is in pressurize class.So fundamentally solve the closing control of high temperature furnace hydraulic pressure course of conveying, and the temperature difference influence of application valve body, and caused the change of melt temperature, mobility and performance.Got rid of because making the with lubricator note of lubricating material cylinder press piston, the gas that lubricant pyrolytic produces simultaneously.
The present invention arranges material preheating above molten aluminium stove, utilize heat conduction, the heat radiation of molten aluminium stove to heat material, be heated to 500 DEG C and can first remove moisture and the crystallization water on material surface, below 500 DEG C, can remove surface moisture, can effectively reduce like this in liquation and dissolve in liquation because the decomposition of material surface moisture produces hydrogen, also can utilize heat energy simultaneously.
The present invention is because adopt vacuum deadweight cast and way that large exert pressure pressurize combines, as long as little barrel is set, adopt lower powered die casting machine just can complete the workpiece die casting that high-power, large barrel could be realized.Because liquation is to carry by vacuum deadweight liquation pressure, do not need to carry by large barrel injection power, can reduce like this drive motors power in hydraulic system, effectively energy-conservation.Increase better effects if under rotating speed situation as adopted magneto to drive in hydraulic system.The present invention particularly waters the enforcement of extrusion process to rotor, can improve significantly electric efficiency.Rotor note aluminium all adopts pressure casting method at present, due to the decomposition gas of lubricant use in the air in air, barrel in die cavity and process, cause squirrel-cage bar and the pore of the inner appearance size of two end ring inequality and a large amount of aluminium oxide after motor rotor die-casting, thereby affected the efficiency of motor.Particularly develop at present high efficiency motor, the cast aluminium quality of its rotor is key point, thereby enforcement of the present invention can improve the die casting quality of rotor and improve electric efficiency, can produce significant economic benefit and social benefit, has huge market application foreground.
The present invention enters the moment of die cavity and the pressure of die cavity contact-making surface depending on process conditions at deadweight potential energy vacuum pouring stage liquation, is by liquid level on pull of vacuum+material deadweight+holding furnace and die cavity material contact-making surface drop pressure+holding furnace is applied the potential energy conversion that these several factors of size of air pressure form jointly and formed.Liquation fluid is in circulation state, this circulation is that kinetic energy causes, produce very large pressure simultaneously mold cavity surface is formed to impulsive force, this impulsive force be formed with the surface quality that is beneficial to special type face, naturally adjust the liquation temperature difference simultaneously, liquation and die cavity contact-making surface part fluid temperature decline, and make the mobility of liquation decline rapidly and affect working surface quality.Thereby the liquid that the effect of this circulation makes self carries out thermal balance has ensured mobility and workpiece surface quality, and the hydrogen that is simultaneously conducive to be contained in liquation is separated out along with the decline of liquid temperature.
And the very little decline rapidly that cannot overcome mould and liquation stiction and the caused mobility of the temperature difference of common cast kinetic energy, cannot form circulation phenomenon, also can only be faint circulation phenomenon for simple workpiece, the surface of the work that does not have certain circulation flow velocity and pressure to form, thereby adopt the vacuum pouring of deadweight potential energy just can obtain good workpiece surface quality and effectively reduce liquation internal hydrogen content in casting process at this one-phase, and then pressurization pressurize, easily obtain good Forming Workpiece.
The workpiece surface quality that the present invention is shaped be by deadweight, potential energy, vacuum self-quantitatively after casting complete cartridge piston liquid level on material is applied to large static pressure, according to the equivalence of pressure in closed container transfer principle, thereby workpiece material is consistent with mold cavity contact-making surface each point pressure.This large static pressure is to realize according to the inverse ratio of the inverse ratio power that effect produces between large operating cylinder, little pressure injection barrel, and the effect of this large static pressure has formed good workpiece surface quality.The use of this method makes die life long, die surface is not formed to jet and destroys, and is difficult for forming the shrinkage phenomenon of surface of the work, and has ensured the intrinsic mechanical properties of workpiece.
And the quality of current common die casting or the final profiled surface of evacuated die-casting process is to realize by common impulsive force and the pressure that the quick injection of cartridge piston is produced after cast.Although this pressure injection method can obtain good surface quality, but because fast shot material produces great jet impact force to mould, affect to a certain extent the service life of mould, because material is that spurting enters finally, affected shaping crystallization and the mechanical performance of workpiece.
The foregoing is only preferred embodiment of the present invention, all equalizations of doing according to the present patent application the scope of the claims change and modify, and all should belong to covering scope of the present invention.
Claims (8)
1. the high static pressure casting forming equipment of vacuum deadweight cast, comprise molten aluminium stove, holding furnace, barrel, cartridge piston, oil cylinder, mold tooling sub-assembly, vacuum buffer tank and vavuum pump, it is characterized in that: the top of described molten aluminium stove is provided with material preheating zone, described molten aluminium stove be connected with holding furnace and tube connector on be provided with keying valve, described holding furnace is connected with the lower end sidepiece of barrel through conveying pipeline, described oil cylinder is arranged at barrel top and drives cartridge piston operation up and down in barrel, the position that contacts with cartridge piston bar, the upper end of described barrel is provided with seal, on described cartridge piston bar, be provided with to the cooling water inlet/outlet pipe of logical cooling water in bar, described barrel charging aperture is positioned among cartridge piston operation stroke, described barrel is positioned at the top of mold tooling sub-assembly, the below of described mold tooling sub-assembly is provided with mould downlink working point and separates preheating zone with two die workpieces, in described mold tooling sub-assembly, be provided with the aluminium liquid cast runner being connected with barrel discharging opening, described aluminium liquid cast runner is connected with mold cavity, the interior chamber of described mold cavity is connected with vacuum pipe through slit evacuation passageway with watering to begin to crop up, described vacuum pipe is connected to vacuum buffer tank, described vacuum buffer tank is connected with vavuum pump.
2. the high static pressure casting forming equipment of a kind of vacuum deadweight cast according to claim 1, it is characterized in that: described holding furnace is connected with in air compressor machine and connecting pipe and is provided with air intake valve, described holding furnace is provided with Pressure gauge, venting valve and safety valve.
3. the high static pressure casting forming equipment of a kind of vacuum deadweight cast according to claim 1, is characterized in that: described conveying pipeline is provided with conveying pipeline heater near on a section of barrel charging aperture.
4. the high static pressure casting forming equipment of a kind of vacuum deadweight cast according to claim 1, is characterized in that: the cross-sectional area of described oil cylinder is large compared with the cross-sectional area of barrel.
5. one kind adopts the casting forming technique of the high static pressure casting forming equipment of vacuum deadweight cast claimed in claim 1, it is characterized in that, carry out according to the following steps: (1) is put into molten aluminium stove by preheated aluminium ingot and carried out overheated melting, and setting the overtemperature melting is 680～800 DEG C; (2) the aluminium liquid after melting enters holding furnace and is incubated by opening and closing valve, and the temperature of insulation is controlled between 670 ~ 780 DEG C; (3) mold tooling sub-assembly and barrel are connected to a fixed, when initial, cartridge piston is positioned at the bottom of barrel and blocks barrel charging aperture, unlatching vacuum valve, startup vavuum pump make the interior air of mold cavity and barrel below air vacuumize through vacuum pipe, make mold cavity and barrel all in vacuum state; (4) in vacuumizing, cylinder putter upwards moves and drives cartridge piston to up, in the time that up stroke exceedes barrel charging aperture top, stop up, now holding furnace is connected with barrel by conveying pipeline, and aluminium liquid is realized and entered barrel and mold cavity from holding furnace Quick pouring under the effect of vacuum and the deadweight of aluminium liquid; (5) in the time that aluminium liquid fills to cartridge piston downside, cylinder putter moves downwards and drives cartridge piston operation downwards to make excessive aluminium liquid automatically return to holding furnace through barrel charging aperture, in the time that exceeding barrel charging aperture below, cartridge piston operation downwards just automatically closes barrel charging aperture and then self-assembling formation quantitative feeding, now realize cartridge piston the workpiece cartridge piston that pressurizes is then continued operation downwards workpiece is applied to high static pressure to realize pressurize, in pressurize, carry out cooling to workpiece; (6) after the cooling rear certain hour of pressurize, dwell time is controlled at 1 ~ 15 second, stays mould to be controlled at 5 ~ 30 seconds cool time, and cylinder putter moves downwards, mold tooling sub-assembly is operation downwards simultaneously, and the stub bar in barrel enters mould downlink working point in company with mould separating barrel; (7), under mechanism, mould separates preheating zone with workpiece translational motion to die workpiece, carries out workpiece demoulding processing; (8) separate behind preheating zone when mould enters above-mentioned die workpiece, be positioned at another die workpiece separate preheating zone the mould of heat treated enter mould downlink working point and rise and barrel combination simultaneously, cartridge piston return carries out lower whorl work.
6. casting forming technique according to claim 5, it is characterized in that: in step (4), the conveying pipeline that molten aluminium stove is connected with barrel is provided with conveying pipeline heater near on a section of barrel charging aperture, makes the plane layer liquation of barrel charging aperture and cartridge piston contact-making surface keep mobile.
7. according to the casting forming technique described in claim 5 or 6, it is characterized in that: in step (4), when need to increase the feeding of deadweight vacuum pouring process material compared with complex part and particular/special requirement workpiece and the pressure of mold cavity Contact material to cavity surface, first pour pressed gas with pressurization to airtight holding furnace, aluminium liquid is finally realized and is entered barrel and mold cavity from holding furnace Quick pouring under the effect of vacuum, the deadweight of aluminium liquid and pressure.
8. casting forming technique according to claim 5, is characterized in that: in step (7) and (8), two die workpieces separate preheating zone and are provided with mould and die preheating device.
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| CN103831418A (en) * | 2012-11-20 | 2014-06-04 | 浙江启铖汽配有限公司 | Die for gravity casting and low-pressure casting |
| CN103397196B (en) * | 2013-08-03 | 2015-12-23 | 福安市广源机电有限公司 | One waters die casting aluminium product a refining unit and technique thereof |
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| CN105642863B (en) * | 2016-01-15 | 2018-01-12 | 江苏飞亚金属制品有限公司 | A kind of extrusion process for preparing aluminium alloy step pedal under vacuum conditions |
| CN106424635A (en) * | 2016-08-29 | 2017-02-22 | 常州市蓝托金属制品有限公司 | Vacuum die casting process for aluminum alloy manufacturing |
| CN106424636A (en) * | 2016-08-29 | 2017-02-22 | 常州市蓝托金属制品有限公司 | Vacuum die casting equipment for aluminum alloy manufacturing |
| CN111906251A (en) * | 2020-07-14 | 2020-11-10 | 安徽省裕康铝业有限公司 | Make things convenient for boiler for aluminum product production of ejection of compact |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN88202405U (en) * | 1988-04-04 | 1988-10-19 | 冶金工业部钢铁研究总院 | Vacuum casting device |
| KR100572581B1 (en) * | 2003-10-15 | 2006-04-24 | 고동근 | Die casting machine of vacuum gravity |
| CN101722295A (en) * | 2008-11-01 | 2010-06-09 | 吴为国 | Method of vacuum pressure casting machine and device thereof |
| CN201618839U (en) * | 2010-03-12 | 2010-11-03 | 何晓南 | Slot type exhauster |
| CN202752579U (en) * | 2012-07-25 | 2013-02-27 | 福安市广源机电有限公司 | Vacuum dead-weight pouring high-static-pressure casting forming equipment |
-
2012
- 2012-07-25 CN CN201210258250.6A patent/CN102728815B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN88202405U (en) * | 1988-04-04 | 1988-10-19 | 冶金工业部钢铁研究总院 | Vacuum casting device |
| KR100572581B1 (en) * | 2003-10-15 | 2006-04-24 | 고동근 | Die casting machine of vacuum gravity |
| CN101722295A (en) * | 2008-11-01 | 2010-06-09 | 吴为国 | Method of vacuum pressure casting machine and device thereof |
| CN201618839U (en) * | 2010-03-12 | 2010-11-03 | 何晓南 | Slot type exhauster |
| CN202752579U (en) * | 2012-07-25 | 2013-02-27 | 福安市广源机电有限公司 | Vacuum dead-weight pouring high-static-pressure casting forming equipment |
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