Background
Horizontal continuous casting refers to a continuous casting type in which molten steel is poured into a horizontally placed mold from a horizontal direction, and the solidification process of a cast slab and the movement in a casting machine are in a horizontal state until reaching a cooling bed. The horizontal continuous casting technology is a technology for producing billets, which is common at present and is suitable for producing small-section billets.
High-temperature alloy and precision alloy are important materials of aerospace components, and nearly ten thousand tons of high-temperature master alloy are cast annually in China, and the production value reaches hundreds of millions of yuan. Although the preparation technology of high-temperature master alloys is relatively mature, a plurality of problems still need to be solved. In the technical field of continuous casting in the world major iron and steel industry countries, the continuous casting ratio of carbon steel alloy is more than 90%, the continuous casting ratio of stainless steel and heat-resistant steel is also more than 60%, but the continuous casting ratio of high-temperature alloy is less than 1%. This is because superalloy master alloys are currently being cast using conventional production processes, namely vacuum-smelted metal molds. However, it is difficult to control the number of inclusions in the master alloy by die casting. During the casting process, the crucible material, the nonmetallic material in the pouring spout and the dross are inevitably brought into the ingot, so that the quality of the high-temperature master alloy is affected. Particularly for use on aerospace components, serious accidents may occur.
On the other hand, the traditional metal die casting production process determines that the casting rod is cooled from bottom to top, so that a casting concentrated shrinkage cavity riser which gathers a large amount of scum on the top of the casting rod is generated, the casting concentrated shrinkage cavity riser must be cut off when in use, the surface of the casting concentrated shrinkage cavity riser needs to be polished or even processed when a high-temperature master alloy bar is used, and finally, the yield of the master alloy is only 80-85%, and a large amount of resource waste is caused.
Some problems of the existing die casting method for producing high-temperature alloy master alloy: (1) the master alloy electrode produced by the casting method of the low-yield low-vacuum induction smelting steel tube for producing the master alloy cast ingot by the die casting method needs to cut the head and the tail, the loss rate of the electrode after each electrode is cut off the head and the tail is about 3-5%, and the high-temperature alloy material is precious and has higher cost.
(2) The shrinkage cavity of the master alloy ingot produced by the die casting method cannot eliminate the larger shrinkage cavity size (the shrinkage cavity diameter is about 15mm wide as shown in fig. 1) formed by the common steel pipe casting method, and the shrinkage cavity size (the shrinkage cavity size is about 5mm wide as shown in fig. 2) of the alloy can be improved by reducing the casting speed and the casting temperature and using a heat insulation riser, but the elimination of electrode shrinkage cavities cannot be fundamentally solved.
(3) Large-size inclusion or slag inclusion in master alloy produced by the die casting method is difficult to remove in the process of pouring the master alloy produced by the die casting method, the risk of entering a die pipe by using a diverter plate body material is increased, the possibility of floating up the large-size inclusion or slag inclusion in molten metal is increased by adopting a horizontal continuous casting tundish structure, and the risk of entering an ingot by the large-size inclusion or slag inclusion is reduced.
(4) The die casting method is high in batch production cost, and because the high-temperature alloy master alloy has increasingly strict requirements on inclusion content, oxygen element/nitrogen element content and secondary shrinkage cavity size of an electrode, a flow distribution disc, a heat insulation riser and a die pipe are inevitably used, the flow distribution disc and the heat insulation riser are consumable materials, the die pipe can only be used once, the use times of the die pipe are generally 5-8 times, but the rejection rate of the master alloy die pipe with special requirements is higher, and the master alloy die pipe is likely to be scrapped after being scalded once.
Disclosure of Invention
The present utility model aims to solve at least one of the technical problems existing in the prior art. Therefore, the utility model provides a device for vacuum horizontal continuous casting and die casting, which can reduce the inclusion content of a finished casting blank, improve the metallurgical quality of the casting blank, improve the yield of special alloy, reduce the production cost and reduce the pollution of production to the atmosphere environment.
An apparatus for vacuum horizontal continuous casting and die casting according to an embodiment of the first aspect of the present utility model is characterized by comprising:
moving a casting vehicle;
the tundish assembly is of an L-shaped pouring gate brick structure and comprises a tundish outer shell and a permanent layer arranged in the tundish outer shell, a ladle nozzle connected with a mobile casting vehicle is arranged above the permanent layer, a funnel is arranged in the permanent layer, the bottom of the funnel is connected with a ladle seat brick, a tundish nozzle is arranged on the ladle seat brick, a sealing cover is arranged on the upper part of the tundish outer shell, and a vacuum tube for extracting air is arranged on the sealing cover;
the crystallizer comprises a crystallization component and a water-proof component which is in threaded connection with one end of the crystallization component, wherein the crystallization component is cylindrical, a graphite sleeve, a long copper sleeve and a stainless steel sleeve are sequentially sleeved on the crystallization component from inside to outside, a short copper sleeve, a water-proof sleeve and a threaded sleeve are sequentially sleeved on the water-proof component from inside to outside, the threaded sleeve is in threaded connection with the stainless steel sleeve, and a crystallizer shell is further sleeved on the crystallization component and the water-proof component;
the safety brake mechanism is arranged between the tundish component and the crystallizer and comprises a hydraulic support plate arranged at the end part of the crystallizer through a flange, a crystallizer water gap is arranged on the flange, a crystallizer sliding plate is slidably arranged on the hydraulic support plate and is in butt joint with the crystallizer water gap, a first round hole matched with the crystallizer water gap is arranged on the crystallizer sliding plate, a chute is arranged on a ladle brick, a tundish sliding plate is arranged in the chute, a second round hole matched with the tundish water gap is arranged on the tundish sliding plate, an aluminum silicate plate is additionally arranged between the crystallizer sliding plate and the tundish sliding plate, and a third round hole communicated with the first round hole and the second round hole is formed in the aluminum silicate plate;
the dummy bar is inserted from one end of the crystallizer far away from the tundish component and extends into the short copper sleeve of the water-proof component, and the insertion end of the dummy bar is in threaded connection with a dummy bar head;
the blank drawing machine comprises a plurality of blank drawing roller groups, wherein each blank drawing roller group comprises two blank drawing rollers which are arranged up and down.
The device for vacuum horizontal continuous casting and die casting has at least the following beneficial effects: 1. the inclusion content of the finished casting blank is reduced, and the metallurgical quality of the casting blank is improved: the traditional vacuum smelting process is top casting, and in the casting process, crucible materials and scum are inevitably brought into cast ingots more or less, so that steel pollution is caused, and the performance of the materials is affected; the utility model is horizontal bottom casting filling, because the specific gravity of various nonmetallic inclusions is smaller than that of molten steel, the nonmetallic inclusions float on the top surface of a molten steel pool and are far away from a filling area, so that cast ingots with less inclusions or no inclusions can be obtained, the metallurgical quality of special alloy casting blanks is greatly improved, and the characteristic has a special significance for preparing high-quality powder special alloy with special purposes.
2. The yield of the special alloy is improved: in the traditional ingot casting and lumbering process, because the ingot is cooled from bottom to top, a casting concentrated shrinkage cavity exists at the top of the ingot, and a great amount of scum is enriched in the concentrated shrinkage cavity, so that a riser is cut off to deliver, the ingot casting and lumbering rate is only about 85%, and a great amount of resource waste is caused; the utility model adopts a horizontal continuous casting mode to form, the volume shrinkage existing in the solidification process can obtain the effective feeding of the molten steel of the tundish, the concentrated shrinkage cavity does not exist, and the continuous casting blank can be improved to about 95 percent.
3. Not only reduces the production cost, but also reduces the pollution of the production to the atmosphere environment: the blank produced by the utility model is formed by quick solidification in a copper mold cooled by water under vacuum condition, has smooth surface, no oxidation and no external pollutant pollution, can be delivered in an as-cast surface mode, eliminates the surface polishing procedure necessary by the traditional process, reduces the production cost and reduces the pollution of production to the atmospheric environment, and is an environment-friendly new product suitable for horizontal continuous casting of medium and small sections (phi 40-phi 80 mm).
According to some embodiments of the utility model, the tundish outer shell comprises a tundish upper part, a tundish middle part, a tundish lower part; the outside of funnel is twined and is had induction coil, the middle part of middle package is paliform and cup joints induction coil's periphery.
According to some embodiments of the utility model, the ladle block is mounted at the lower part of the tundish and extends to the bottom end of the hopper, and a runner is arranged in the ladle block and is communicated with the bottom end of the hopper.
According to some embodiments of the utility model, guide roller ways are arranged at the front end and the rear end of the blank drawing machine, and each guide roller way comprises a movable bracket and a plurality of free rollers arranged on the movable bracket.
According to some embodiments of the utility model, the crystallizer cooling system comprises a water reservoir, a circulating water inlet pipe and a circulating water outlet pipe which are communicated between the crystallizer and the water reservoir, and a heat exchange mechanism connected with the circulating water inlet pipe in parallel, wherein a water suction pump is connected with the circulating water inlet pipe in series, a cooling cavity is arranged between the crystallizer shell and the crystallization component, and the circulating water inlet pipe and the circulating water outlet pipe are respectively communicated with the cooling cavity.
Additional aspects and advantages of the utility model will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the utility model.
Detailed Description
Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.
In the description of the present utility model, it should be understood that references to orientation descriptions such as upper, lower, front, rear, left, right, etc. are based on the orientation or positional relationship shown in the drawings, are merely for convenience of description of the present utility model and to simplify the description, and do not indicate or imply that the apparatus or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the present utility model.
In the description of the present utility model, a number means one or more, a number means two or more, and greater than, less than, exceeding, etc. are understood to not include the present number, and above, below, within, etc. are understood to include the present number. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.
In the description of the present utility model, unless explicitly defined otherwise, terms such as arrangement, installation, connection, etc. should be construed broadly and the specific meaning of the terms in the present utility model can be reasonably determined by a person skilled in the art in combination with the specific contents of the technical scheme.
Referring to fig. 1 to 3, an apparatus for vacuum horizontal continuous casting and die casting according to an embodiment of a first aspect of the present utility model is characterized by comprising:
moving a casting vehicle;
the tundish assembly 200 is in an L-shaped pouring gate brick structure and comprises a tundish outer shell 210 and a permanent layer 220 arranged in the tundish outer shell 210, a ladle nozzle 230 connected with a mobile casting vehicle is arranged above the permanent layer 220, a funnel 240 is arranged in the permanent layer 220, the bottom of the funnel 240 is connected with a ladle block 250, a tundish nozzle 260 is arranged on the ladle block 250, a tundish nozzle 210 is arranged on the ladle block, a sealing cover 270 is arranged on the upper part of the tundish outer shell 210, a vacuum tube 280 for extracting air is arranged on the sealing cover 270, and in the working process, the sealing cover 270 is closed, and vacuum treatment is carried out on the inside of the permanent layer 220 by utilizing the vacuum tube 280 to ensure that molten steel is melted in a vacuum state;
the crystallizer 300 comprises a crystallization component 310 and a water isolation component 320 which is in threaded connection with one end of the crystallization component 310, wherein the crystallization component 310 is in a cylinder shape, a graphite sleeve 330, a long copper sleeve 340 and a stainless steel sleeve 350 are sequentially sleeved with the crystallization component 310 from inside to outside, a short copper sleeve 360, a water isolation sleeve 370 and a threaded sleeve 380 are sequentially sleeved with the water isolation component 320 from inside to outside, the threaded sleeve 380 is in threaded connection with the stainless steel sleeve 350, and the crystallization component 310 and the water isolation component 320 are also sleeved with a shell of the crystallizer 300;
the safety brake mechanism 400 is installed between the tundish assembly 200 and the crystallizer 300, and comprises a hydraulic support plate 410 installed at the end part of the crystallizer 300 through a flange, a crystallizer 300 water gap is formed in the flange, a crystallizer 300 sliding plate is installed on the hydraulic support plate 410 in a sliding mode, the crystallizer 300 sliding plate is abutted to the crystallizer 300 water gap, a first round hole matched with the crystallizer 300 water gap is formed in the crystallizer 300 sliding plate, a sliding groove 251 is formed in the ladle brick 250, a tundish sliding plate 450 is installed in the sliding groove 251, a second round hole matched with the tundish water gap 260 is formed in the tundish sliding plate 450, an aluminum silicate plate 470 is additionally installed between the crystallizer 300 sliding plate and the tundish sliding plate 450, and a third round hole communicated with the first round hole and the second round hole is formed in the aluminum silicate plate 470;
a dummy bar 500 inserted from an end of the mold 300 away from the tundish assembly 200 and extending into the short copper sheath 360 of the water blocking assembly 320, the dummy bar 500 having a dummy head 510 screwed to an insertion end thereof;
the degerming machine 600 comprises a plurality of degerming roller 610 groups, wherein the degerming roller 610 groups comprise two degerming rollers 610 arranged above each other.
The vacuum pouring (continuous casting) process route of the device for vacuum horizontal continuous casting and die casting of the embodiment is as follows: A. preparation for production
The tundish adopts a 'pit furnace + L-shaped runner brick diversion structure' to be connected with a water gap of the crystallizer 300 and is arranged on a movable casting vehicle. The casting vehicle is moved to the outside of the furnace chamber before production, and the dummy ingot head 510, the gate brick of the crystallizer 300 and the like are installed. The dummy bar 500 is installed in the dummy bar feeding device, the dummy bar head 510 is horizontally fed into the casting starting position in the crystallizer 300 (the front end of the dummy bar head 510 is 80-90 mm away from the copper bush inlet), and the dummy bar head 510 is fed so as to avoid damaging the graphite bush 330 and the copper bush of the crystallizer 300; purging dummy bar head 510 with compressed air to remove contaminants and moisture and keep the dummy bar 500 head clean and dry; prying the dummy bar head 510 into the crystallizer 300 by using a crow bar or a copper drill rod and the like, enabling the distance between the dummy bar head 510 and the periphery of the crystallizer 300 to be uniform, and then plugging a gap between the copper sleeve and the dummy bar head 510 by using an asbestos rope; the copper sleeve is not damaged when the asbestos rope is plugged, and the periphery of the asbestos rope is uniformly plugged. The dummy bar head 510 and the outlet of the crystallizer 300 are sealed by adopting O-shaped sealing rings. While tundish brick cup 250, etc. are installed. The tundish and the crystallizer 300 are butted and locked by bolts and belleville springs.
The movable casting car is introduced into the furnace chamber to pour steel, and the movable ingot mould chamber sealing door is locked in place and connected with the outlet sealing ring of the crystallizer 300. After the connection and sealing are completed, the ingot mould chamber sealing door is assembled, and the preparation is completed.
The tundish- -pit furnace + L-shaped ladle block 250 is heated by resistance (> 0 ℃) before steel casting, and is measured by a buried armoured thermocouple.
And after the mobile casting vehicle runs in place, hydraulic locking and positioning are adopted.
B. Smelting and continuous casting production
The induction furnace filled with furnace burden is vacuumized after the furnace door is closed, and is electrified, heated and melted (according to conventional operation). About 30 minutes before tapping, the tundish assembly 200 is heated by the open pit furnace. After the argon filling and pressure regulating of the smelting furnace, an ingot mould chamber sealing door is opened, and a dummy bar head 510 is connected with the dummy bar 500.
During tapping, the tilting furnace body pours molten steel into the ladle nozzle 230 (a steel flowing groove) according to the process requirement speed, and the casting can be carried out according to the general horizontal continuous casting operation requirement at the beginning of casting.
And simultaneously closing the pit furnace for electric heating. The crystallizer 300 outlet sealing means is removed.
The molten steel liquid level is checked through the peeping mirror and the television probe, and the casting temperature can be slightly adjusted by opening and closing the pit furnace.
The device for vacuum horizontal continuous casting and die casting has at least the following beneficial effects: 1. the inclusion content of the finished casting blank is reduced, and the metallurgical quality of the casting blank is improved: the traditional vacuum smelting process is top casting, and in the casting process, crucible materials and scum are inevitably brought into cast ingots more or less, so that steel pollution is caused, and the performance of the materials is affected; the utility model is horizontal bottom casting filling, because the specific gravity of various nonmetallic inclusions is smaller than that of molten steel, the nonmetallic inclusions float on the top surface of a molten steel pool and are far away from a filling area, so that cast ingots with less inclusions or no inclusions can be obtained, the metallurgical quality of special alloy casting blanks is greatly improved, and the characteristic has a special significance for preparing high-quality powder special alloy with special purposes.
2. The yield of the special alloy is improved: in the traditional ingot casting and lumbering process, because the ingot is cooled from bottom to top, a casting concentrated shrinkage cavity exists at the top of the ingot, and a great amount of scum is enriched in the concentrated shrinkage cavity, so that a riser is cut off to deliver, the ingot casting and lumbering rate is only about 85%, and a great amount of resource waste is caused; the utility model adopts a horizontal continuous casting mode to form, the volume shrinkage existing in the solidification process can obtain the effective feeding of the molten steel of the tundish, the concentrated shrinkage cavity does not exist, and the continuous casting blank can be improved to about 95 percent.
3. Not only reduces the production cost, but also reduces the pollution of the production to the atmosphere environment: the blank produced by the utility model is formed by quick solidification in a copper mold cooled by water under vacuum condition, has smooth surface, no oxidation and no external pollutant pollution, can be delivered in an as-cast surface mode, eliminates the surface polishing procedure necessary by the traditional process, reduces the production cost and reduces the pollution of production to the atmospheric environment, and is an environment-friendly new product suitable for horizontal continuous casting of medium and small sections (phi 40-phi 80 mm).
According to some embodiments of the utility model, the tundish outer shell 210 includes a tundish upper part, a tundish middle part, and a tundish lower part; an induction coil 241 is wound outside the funnel 240, and the middle of the tundish is fence-shaped and is sleeved on the periphery of the induction coil. The middle of the tundish in this embodiment protects the induction coil 241 from the outside.
Further, according to some embodiments of the present utility model, the ladle block 250 is mounted at the lower portion of the tundish and extends to the bottom end of the hopper 240, and a runner is provided in the ladle block 250, and communicates with the bottom end of the hopper 240. After the liquid metal enters the funnel 240 from the ladle nozzle 230, the liquid metal flows out of the pouring gate and enters the crystallizer 300, and the liquid metal can be heated and insulated through the induction coil 241 outside the funnel 240, so that cooling solidification is prevented.
Further, according to some embodiments of the present utility model, the stretch-draw machine 600 is provided with guiding tables at both front and rear ends, the guiding tables including a movable bracket, and a plurality of free rollers mounted on the movable bracket. The free rollers support and convey the pulled materials, so that the pulled materials are prevented from deforming under the action of gravity.
Further, according to some embodiments of the present utility model, a crystallizer cooling system 700 is further included, the crystallizer cooling system 700 includes a water reservoir 710, a circulation water inlet pipe 720 and a circulation water outlet pipe 730 connected between the crystallizer 300 and the water reservoir 710, and a heat exchange mechanism 740 connected in parallel with the circulation water inlet pipe 720, a water suction pump 750 is connected in series with the circulation water inlet pipe 720, a cooling cavity 391 is disposed between the shell of the crystallizer 300 and the crystallization component 310, and the circulation water inlet pipe 720 and the circulation water outlet pipe 730 are respectively connected with the cooling cavity 391. In this embodiment, the heat exchange mechanism 740 is arranged on the water inlet pipe in parallel, so that when the water temperature in the water inlet pipe cannot meet the cooling requirement, the circulating water before entering the crystallizer 300 can be cooled by the heat exchange mechanism 740, the smoothness of production is ensured, and the production requirement of the superalloy master alloy can be met.
The embodiments of the present utility model have been described in detail with reference to the accompanying drawings, but the present utility model is not limited to the above embodiments, and various changes can be made within the knowledge of one of ordinary skill in the art without departing from the spirit of the present utility model.