Bottom pouring ladle hot charging water gap stopper rod process method and special tool combination

Abstract

The invention discloses a bottom pouring ladle hot charging water gap stopper rod process method and a special tool combination, according to the process, in a hot state before pouring of a bottom pouring ladle is completed and the temperature of a ladle wall is reduced to 800 DEG C, stopper rod hot-state dismounting and replacing, water gap hot-state dismounting and replacing and brick cup hot-state grouting maintenance are completed, and reuse can be achieved after transient temperature rise and heat preservation; the special tool combination comprises stopper storehouses, stopper suspension arm equipment, a water gap pulling device and the like which are matched in a one-to-one mode. The method overcomes the defects of high energy consumption, long ladle preparation period and the like of the traditional process, greatly saves energy, shortens the ladle preparation time, prolongs the service life of refractory materials, fills the blank of domestic thermal-state disassembly and assembly technology, and is suitable for the field of pouring of various bottom pouring ladles.

Description

Technical Field

[0001] This invention relates to the field of casting equipment and processes, and more specifically, to a bottom-fill ladle hot-filling process for a sprue stopper rod and a special tooling assembly. Background Technology

[0002] Bottom-pouring ladles are core equipment in foundry enterprises. They are commonly used for casting operations in fields such as railway wheels and engineering machinery castings. The traditional bottom-pouring ladle preparation process is as follows: after the previous batch of castings is completed, a cooling fan is used to force the ladle from a red-hot state of over 1000°C to room temperature. Then, the sprue and stopper are removed, cleaned, and installed at room temperature. Finally, the ladle is baked with natural gas to the operating temperature (above 1000°C) before it can be put into use again.

[0003] This traditional process has obvious drawbacks: repeated cooling and heating of the ladle causes a large amount of heat loss, resulting in huge consumption of natural gas and electricity; the ladle preparation cycle is as long as 10 hours or more, the number of ladles is large, and it occupies space and capital; frequent temperature shocks reduce the service life of refractory materials, increase maintenance costs and carbon emissions, which is not in line with the national "dual carbon" policy. Summary of the Invention

[0004] The purpose of this invention is to provide a bottom-fill package hot-fill nozzle plug rod process, which can overcome to some extent the problems of high energy consumption, long cycle, low efficiency and large refractory material loss of the traditional room temperature package preparation process.

[0005] The technical solution of this invention is implemented as follows: A hot-filling process for bottom-pouring ladle nozzle plugs involves using a plug rod lifting device to press the plug rod firmly onto the nozzle brick while the bottom-pouring ladle is hot, thus blocking the nozzle head. The lifting device has a crossarm at its end for connecting the plug rod. The process includes replacing the nozzle and plug rod, and maintaining the nozzle seat brick, while the bottom-pouring ladle is still hot after the previous pouring and before the wall temperature drops to 800°C. After a short period of heating and heat preservation, the bottom-pouring ladle can be reused. The specific steps include: S1. Hot replacement of stopper rod: The stopper rod is removed from the horizontal arm of the bottom injection press by using the stopper rod lifting equipment. The horizontal arm is then transferred to the corresponding stopper rod storage position and locked. The new stopper rod is then assembled onto the horizontal arm. The new stopper rod is installed and adjusted according to the pre-marked position of the stopper rod storage. The horizontal arm is then reinstalled into the bottom injection press by the stopper rod lifting equipment, so that the stopper rod head blocks the water inlet and the horizontal arm is locked in position. S2. Hot replacement of nozzles: The old nozzles on the bottom injection bag are removed by using a nozzle pulling device. Then, the new nozzles are installed and fixed after being aligned with the centering brick hole by a nozzle installation machine. The outer wall of the new nozzles is coated with refractory mortar. After installation, a nozzle cover plate is installed to seal the nozzles. S3. Hot maintenance of seat bricks: Hot repair of seat bricks is carried out by grouting. After completion, the bottom grouting pot is briefly heated and kept warm to complete the preparation of the pot. The stopper rod boom device includes a lifting hydraulic cylinder, which is vertically set, and a horizontally set boom is set on its top telescopic rod. One end of the boom is equipped with a handle, and the other end is connected to a horizontal arm through a lifting lug. The horizontal arm is used to connect the stopper rod, which is vertically set and its top is fixed to the horizontal arm.

[0006] Furthermore, in step S1, the stopper barrel is set up one-to-one with the bottom injection package. One horizontal arm corresponds to only one bottom injection package and one stopper barrel station. The stopper barrel is pre-calibrated after the bottom injection package is completed and the water inlet is installed at room temperature. The horizontal arm is locked on the positioning plate, the stopper is installed and adjusted to the optimal position, and the stopper head position is calibrated in the stopper barrel and the calibration fixture is locked.

[0007] Further, in step S2, the sprue pulling device includes a hydraulic cylinder and a pulling column. The output end of the hydraulic cylinder is connected to the pulling column, and an eccentric clamping plate is hinged to the end of the pulling column. A limiting part is provided on the pulling column to prevent the eccentric clamping plate from rotating excessively. The eccentric clamping plate has a retracted state and an open state on the pulling column. The disassembly operation of the sprue pulling device includes: first, laying the bottom injection bag horizontally so that the sprue hole is in a horizontal state; then, adjusting the eccentric clamping plate on the pulling column to the retracted state; and then disassembling the entire device. The sprue passes horizontally through the sprue hole. When the eccentric clamping plate exceeds the sprue hole, it falls under the action of gravity and is in an open state. Then, the hydraulic cylinder is activated to pull the sprue through the eccentric clamping plate, thus completing the sprue removal. The sprue removal device also includes a bracket, which includes a circular base plate. The output end of the hydraulic cylinder is connected to the center of one side of the base plate, and the other side is provided with the pulling column and multiple support columns. The multiple support columns are evenly arranged around the central axis of the base plate. When the pulling column passes through the base plate hole, the multiple support columns abut against the wall of the bottom injection pot to form a stable support.

[0008] Further, in step S2, the sprue installation machine includes a base, a drive unit, a linkage cantilever, and a sprue positioning shaft. The drive unit is mounted on the base, and its end is connected to the sprue positioning shaft via the linkage cantilever. During sprue installation, the bottom injection bag is laid horizontally, and the new sprue is placed on the sprue positioning shaft and aligned with the hole in the base brick. Then, the drive unit drives the sprue positioning shaft to push the sprue into the hole in the base brick, completing the sprue assembly. The drive unit uses a lifting handle, and the linkage cantilever and the sprue positioning shaft are driven by hand-cranking the lifting handle to push the sprue into the hole in the base brick.

[0009] Furthermore, in step S3, the grouting material for the hot repair of the seat brick is a slurry made of refractory mortar and silica sol.

[0010] Furthermore, in step S2, the bonding mortar between the new water inlet and the base brick is a mixture of refractory mortar powder with an Al2O3 content ≥75%, silica sol, and carbon powder, wherein the carbon powder is added in a proportion of 5% to 9%.

[0011] Furthermore, the sprue is made of fused silica and has a wall thickness of 3–5 cm.

[0012] Furthermore, the lining of the bottom injection pot is constructed with high-alumina bricks with an Al2O3 content of ≥75%, and the seat bricks are high-alumina bricks with an Al2O3 content of ≥85% or aluminum-magnesium-carbon materials.

[0013] Furthermore, in the process, the sprue and stopper are replaced once for each casting cycle to ensure that the sprue and stopper are in the optimal state of being free from corrosion and adsorption during casting.

[0014] This invention also provides a special tooling assembly for hot-filling sprue plug rods in bottom injection packages to realize the above-mentioned bottom injection package hot-filling sprue plug rod process. The assembly includes a plug rod magazine, a plug rod lifting arm, a sprue pulling device, a sprue installation machine, and a hot-filling grouting repair device for the base brick, all matched one-to-one with the bottom injection package. The plug rod magazine includes a positioning base, a positioning plate, and a plug rod head positioner. The positioning plate is mounted on the positioning base, and a positioning pin hole is provided on the positioning plate. A positioning pin is provided on the cross arm, and by inserting the positioning pin into the positioning pin hole, the plug rod head on the cross arm is precisely positioned on the plug rod head positioner to complete the plug rod calibration and locking.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. Significantly reduced energy consumption: After the bottom injection pot is poured, it does not need to be cooled to room temperature. Replacement and maintenance can be completed directly in the hot state, avoiding heat waste caused by repeated cooling and heating, and significantly saving energy consumption such as natural gas and electricity, which is in line with the "dual carbon" policy orientation.

[0016] 2. Significantly improved kit preparation efficiency: The kit preparation cycle has been shortened from the traditional 8 hours to less than 2 hours, which greatly reduces the kit preparation time, reduces the number of bottom injection kits, saves production space and equipment capital, and improves production continuity.

[0017] 3. Reduced refractory material wear: It avoids the repeated high-low-high temperature shocks experienced by the bottom injection liner, extends the service life of refractory materials such as liner and bedding bricks, reduces the cost of refractory material replacement and maintenance, and reduces carbon emissions.

[0018] 4. High practicality: The process steps are simple and easy to operate. The special tooling combination structure is reasonable and easy to debug. It can be adapted to existing bottom injection ladles without major modifications to the bottom injection ladles. It is easy to promote and apply, and is suitable for various fields that use bottom injection ladles for casting, such as railway wheels and engineering machinery castings. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a flowchart of the bottom-fill package hot-fill nozzle plugging process of the present invention; Figure 2 A schematic diagram of the structure of the hot-fitted stopper rod in the stopper rod boom device of the present invention; Figure 3 Schematic diagram of the stopper rod library of the present invention; Figure 4 A schematic diagram of the sprue pulling device of the present invention; Figure 5 A schematic diagram of the sprue installation machine of the present invention.

[0021] In the picture: 1-Lifting hydraulic cylinder; 2-Boom; 3-Handle; 4-Lifting lug; 5-Horizontal arm; 6-Plug rod; 7-Positioning base; 8-Positioning plate; 9-Plug rod head positioner; 10-Linkage cantilever; 12-Hydraulic cylinder; 13-Pull-out column; 15-Sprue positioning shaft; 16-Support column; 17-Base; 18-Lifting handle; 19-Bottom injection bag; 20-Positioning pin; 21-Lifting rope; 22-Seat plate. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0023] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0024] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0025] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this invention is in use. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. In addition, the terms "first," "second," and "third," etc., are only used to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0026] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0027] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0028] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0029] Example 1 Reference Figures 1-5 This embodiment provides a hot-filling process for bottom-filling ladle stoppers and a dedicated tooling assembly, applicable to bottom-filling ladle 19 (used for casting railway wheel parts). Combined with the dedicated tooling assembly, it enables rapid ladle preparation under hot conditions. The specific implementation process is as follows: I. Structure and Debugging of Special Tooling Assembly The dedicated tooling assembly in this embodiment includes a stopper rod magazine, a stopper rod lifting device, a sprue pulling device, a sprue installation machine, and a hot grouting repair device for the seat brick, all matched one-to-one with the bottom grouting package 19. The specific structure and debugging of each tooling assembly are as follows: 1. Stopper rod lifting equipment The stopper rod lifting device includes a lifting hydraulic cylinder 1, a lifting boom 2, a handle 3, a lifting lug 4, and a horizontal arm 5. The lifting hydraulic cylinder 1 is vertically fixed on the ground base 17, which can meet the lifting load requirements in high-temperature environments. The lifting boom 2 can be made of heat-resistant alloy steel and is horizontally fixed on the top telescopic rod of the lifting hydraulic cylinder 1. The handle 3 is welded to one end of the lifting boom 2 (for easy operation by the operator), and the other end is connected to the horizontal arm 5 through the lifting lug 4. The horizontal arm 5 is used to fix the stopper rod 6, and a positioning pin 20 is also provided on the horizontal arm 5 for positioning in conjunction with the positioning plate 8 of the stopper rod magazine.

[0030] Debugging: After installation, start the lifting hydraulic cylinder 1 and test the smoothness of the lifting of the boom 2 to ensure that the telescopic rod can extend and retract without jamming; adjust the level of the cross arm 5 to ensure that the stopper rod 6 is in a vertical position after being fixed.

[0031] 2. Stopper bank The stopper rod magazine and the bottom injection package 19 are matched one-to-one. Each bottom injection package 19 corresponds to one stopper rod magazine, and each stopper rod magazine has one stopper rod magazine station, corresponding to one horizontal arm 5 (that is, one horizontal arm 5 corresponds to only one bottom injection package 19 and one stopper rod magazine station). The stopper rod magazine includes a positioning base 7, a positioning plate 8, and a stopper rod head positioner 9. The positioning plate 8 is set on the top of the positioning base 7. The positioning plate 8 is fixed on the positioning base 7 and has a positioning pin hole that matches the positioning pin 20 of the horizontal arm 5. The stopper rod head positioner 9 has a stopper rod magazine station that matches the shape of the stopper rod head and is used to place and position the stopper rod head.

[0032] Pre-calibration process of stopper rod magazine: After the bottom injection bag 19 is completed, the water inlet is installed at room temperature. The positioning pin 20 of the horizontal arm 5 is inserted into the positioning pin hole of the positioning plate 8 to lock the horizontal arm 5. The stopper rod 6 is installed on the clamp of the horizontal arm 5. The height of the lifting hydraulic cylinder 1 and the angle of the boom 2 are adjusted so that the stopper rod head is exactly blocking the water inlet (achieving the optimal sealing position). Then the horizontal arm 5 is disassembled and reinstalled on the positioning plate 8 of the stopper rod magazine. The position of the stopper rod head locator 9 is adjusted so that the stopper rod head is exactly placed in the groove of the locator. The calibration fixture is locked to complete the pre-calibration of the stopper rod magazine, ensuring that the new stopper rod 6 can be quickly positioned without repeated adjustments.

[0033] 3. Sprue pulling device The sprue pulling device includes a bracket, a hydraulic cylinder 12, a pulling column 13, an eccentric clamping plate, and a limiting part. The bracket includes a circular seat plate 22. The output end of the hydraulic cylinder 12 can be connected to the center of one side of the seat plate 22 through a flange, and the pulling column 13 is welded to the center of the other side. At the same time, multiple support columns 16 are evenly arranged around the central axis of the seat plate 22. Heat-resistant rubber pads can be installed at the ends of the support columns 16 to abut against the wall of the bottom injection jar 19 to form stable support.

[0034] The end of the pull column 13 is hinged to an eccentric clamping plate (which can be made of wear-resistant and heat-resistant steel) via a pin. The eccentric clamping plate can rotate around the pin to form a retracted state and an open state. A limiting block (as a limiting part) is welded on the pull column 13 to prevent the eccentric clamping plate from rotating excessively (the maximum rotation angle is 90°) and to ensure that the eccentric clamping plate can reliably contact the inner wall of the nozzle after it is opened.

[0035] Debugging: Adjust the eccentric clamp to the retracted state (thickness less than the inner diameter of the sprue) and test whether it can pass smoothly through the sprue hole; after passing the eccentric clamp through the simulated sprue hole, observe whether it can automatically open under gravity and whether the limiting block can effectively limit its rotation angle; start the hydraulic cylinder 12 and test the extension and retraction stability of the pull column 13 to ensure that the sprue can be reliably pulled after the eccentric clamp opens without slippage; place the support column 16 against the simulated wall and test the stability of the bracket to ensure that there is no shaking during the pulling process.

[0036] 4. Sprue installation machine The sprue installation machine includes a base 17, a drive unit (lifting handle 18), a linkage cantilever 10, and a sprue positioning shaft 15. The base 17 can be made of welded steel plate to ensure no shaking during installation. The lifting handle 18 is located on the base 17 and adopts a hand-cranked structure for easy manual control by the operator. The end of the lifting handle 18 is connected to the linkage cantilever 10. The linkage cantilever 10 is composed of two hinged connecting rods, and the end is welded to the sprue positioning shaft 15 (the diameter matches the inner diameter of the sprue, the surface is smooth, and it is easy to fit the sprue).

[0037] Debugging: Place the new sprue onto the sprue positioning shaft 15 and test the sprue's alignment to ensure that the sprue axis coincides with the positioning shaft axis; manually crank the lifting handle 18 to test the extension and retraction stability of the linkage cantilever 10 to ensure that the sprue can be pushed forward smoothly; adjust the length of the linkage cantilever 10 so that the sprue positioning shaft 15 can be accurately aligned with the simulated seat brick hole, test the smoothness of the sprue pushing process, and ensure that there is no jamming and that the sprue can fit tightly with the seat brick hole after being pushed in.

[0038] 5. Hot grouting repair device for seat bricks The hot grouting repair device for mortar bricks includes a grouting pump, a grouting pipe, and a material bucket. The grouting pump can be a small high-pressure grouting pump, the grouting pipe is made of heat-resistant steel pipe, and the material bucket is used to store the grouting material (a slurry made of refractory mortar and silica sol). The outer layer of the material bucket is equipped with a heat insulation layer to prevent the slurry from solidifying in a high-temperature environment.

[0039] Debugging: Pour the grouting material into the bucket, stir it evenly, and test the grouting pressure and flow rate of the grouting pump to ensure smooth grouting without blockage; align the grouting pipe with the damaged part of the simulated seat brick, test the grouting effect, and ensure that the grout can fill the damaged area evenly without leakage or flow.

[0040] 6. Auxiliary tooling Equipped with high-temperature protective gloves, remote control handles (linked with stopper boom equipment and nozzle pulling device), thermometers (for real-time monitoring of the wall temperature of bottom injection bag 19), nozzle covers (for sealing the nozzle after installing a new nozzle), and other auxiliary tools, to ensure operator safety and smooth process implementation.

[0041] II. Implementation Process of Bottom Injection Bundle Hot Filling Gate Stopper Rod In this embodiment, the bottom grouting bag 19 is constructed with high-alumina bricks with an Al2O3 content of not less than 75%, the seat bricks are constructed with high-alumina bricks with an Al2O3 content of 80%, the sprue is made of fused silica with a wall thickness of 4cm, the bonding mortar between the new sprue and the seat brick is a mixture of refractory mortar powder, silica sol and carbon powder with an Al2O3 content of not less than 75% (the carbon powder addition ratio is 7%), the grouting material for hot repair of the seat brick is a slurry made of refractory mortar and silica sol, and the sprue and stopper rod 6 are replaced after each furnace pour.

[0042] The specific process steps are as follows: 1. Preparations before pouring Using the stopper rod lifting device, operate the lifting hydraulic cylinder 1 and the lifting arm 2 to assemble the stopper rod 6 (which has been pre-marked in the stopper rod magazine) onto the clamp of the horizontal arm 5 and tighten the bolts; adjust the angle and lifting height of the lifting arm 2, and lower the stopper rod 6 vertically into the bottom pouring pot 19 so that the stopper rod head is pressed tightly against the nozzle brick, completely blocking the nozzle; lock the horizontal arm 5 in place to ensure that the stopper rod 6 does not loosen or shift during the pouring process, and prevent molten steel leakage.

[0043] 2. Pouring operation After completing the pre-pouring preparations, the molten steel pouring operation was carried out. During the pouring process, the temperature of the bottom ladle 19 was monitored in real time to ensure that the pouring process was smooth and there were no abnormalities such as molten steel leakage.

[0044] 3. Hot replacement and maintenance (to be completed after casting and before the wall temperature of bottom casting ladle 19 drops to 800℃) (1) Step S1: Hot replacement of stopper rod 6 ① Disassembling the old stopper rod 6: The operator raises the hydraulic cylinder 1 of the stopper rod lifting equipment, which drives the lifting arm 2 and the horizontal arm 5 to rise, lifting the old stopper rod 6 from the bottom injection pot 19 and detaching it from the nozzle brick; rotate the lifting arm 2 to transfer the old stopper rod 6 to the position above the corresponding stopper rod storage station, slowly lower the horizontal arm 5, insert the positioning pin 20 of the horizontal arm 5 into the positioning pin hole of the stopper rod storage positioning plate 8, lock the horizontal arm 5, and put the stopper rod head of the old stopper rod 6 into the stopper rod head locator 9 to complete the disassembly of the old stopper rod 6.

[0045] ② Install the new stopper rod 6: Take the new stopper rod 6 out of the stopper rod magazine and reassemble the top of the new stopper rod 6 onto the cross arm 5; adjust the lifting hydraulic cylinder 1 and the boom 2, and lower the new stopper rod 6 vertically into the bottom injection bag 19. According to the pre-calibrated position of the stopper rod magazine, make the stopper rod head accurately aligned with the water inlet and press it tightly onto the water inlet brick to ensure that the water inlet is completely blocked; lock the cross arm 5 in position to complete the hot replacement of the stopper rod 6.

[0046] (2) Step S2: Hot replacement of water inlet ① Dismantling the old sprue: Place the bottom injection bag 19 horizontally using a flipping device to ensure the sprue orifice is horizontal; the sprue pulling device can be suspended from a beam or roof using rope 21. Operators can wear high-temperature protective gloves. Adjust the eccentric clamp on the pulling column 13 of the sprue pulling device to a retracted state (thickness less than the inner diameter of the sprue). Pass the pulling column 13 horizontally through the sprue orifice. When the eccentric clamp extends beyond the sprue orifice, it will automatically fall under gravity, opening up (at this time, the eccentric clamp is in contact with the inner wall of the sprue, and the limiting block prevents excessive rotation). Adjust the support position so that multiple support columns 16 abut against the wall of the bottom injection bag 19, forming stable support. Figure 4 Start the hydraulic cylinder 12, which pulls the pull column 13. Because multiple support columns 16 abut against the bottom of the column and the wall of the injection jack 19, the old sprue can be moved outward by the eccentric clamping plate until the old sprue is completely removed from the seat brick hole, thus completing the disassembly of the old sprue. Then, turn off the hydraulic cylinder 12, adjust the eccentric clamping plate to the retracted state, and pull the pull column 13 out of the seat brick hole.

[0047] ② Install the new sprue: Apply a layer of refractory mortar evenly to the outer wall of the new sprue, place the new sprue onto the sprue positioning shaft 15 of the sprue installation machine, adjust the position of the sprue to ensure that the axis of the sprue coincides with the axis of the sprue positioning shaft 15; keep the bottom injection bag 19 in a horizontal position, adjust the position of the sprue installation machine so that the sprue positioning shaft 15 is aligned with the seat brick hole, manually crank the lifting handle 18 to drive the connecting rod cantilever 10 and the sprue positioning shaft 15 forward, and smoothly push the new sprue into the seat brick hole until the new sprue fits tightly with the seat brick hole; remove the sprue positioning shaft 15, install a sprue cover plate on the outside of the new sprue to lock the sprue in place and prevent debris from entering the sprue during the subsequent insulation process, thus completing the hot replacement of the new sprue.

[0048] (3) Step S3: Hot maintenance of the seat brick ① Brick inspection: Operators monitor the temperature of the brick using a thermometer (ensuring it is above 800℃ in a hot state), observe whether there are any defects such as damage or missing pieces on the inner wall of the brick hole, and determine the location for grouting repair.

[0049] ② Hot grouting: Pour the slurry made of refractory mortar and silica sol into the material bucket of the hot grouting repair device for the base brick and stir evenly; align the grouting pipe with the damaged part of the base brick, start the grouting pump, and inject the slurry into the damaged area under high pressure until the slurry fills the damaged area without gaps or flow; turn off the grouting pump, pull out the grouting pipe, and use a heat-resistant tool to smooth the grouting area to ensure that the inner wall of the base brick hole is flat.

[0050] ③ Brief heating and heat preservation: After the grouting is completed, the bottom grouting pot 19 is briefly heated using a natural gas spray gun to raise the temperature of the bottom grouting pot 19 wall to 1000℃ (the same as the pouring temperature) and then heat preservation is performed to ensure that the grouting slurry is fully bonded to the seat brick. At the same time, it is ensured that the new water nozzle and the new stopper 6 are tightly bonded to the seat brick and the water nozzle brick, thus completing the preparation of the pot.

[0051] Note that the hot disassembly and assembly of the stopper rod and sprue in steps S1 and S2 above are performed simultaneously and alternately. First, remove the stopper rod and sprue in sequence, then install the sprue and stopper rod in sequence. Figure 1 .

[0052] 4. Re-pouring After the preparation of the ladle is completed, the bottom pouring ladle 19 is flipped to a vertical position, and the next pouring operation can be carried out. The entire preparation process takes no more than 2 hours, which is significantly shorter than the traditional process (more than 10 hours).

[0053] III. This plan also provides a detailed experimental procedure: Because the tap nozzles are disassembled and the seat brick holes are cleaned after each furnace run to facilitate the installation of the next tap nozzle, mechanical cleaning exacerbates the damage to the inner wall of the seat bricks. Simultaneously, the lack of repair of the seat bricks under high temperatures further accelerates their erosion. To address the reasons for the low lifespan of the seat bricks, a series of tackling experiments were conducted, mainly focusing on the following three aspects: (1) Improve the corrosion resistance of the seat bricks. The Al2O3 content of the original high alumina brick seat bricks was increased from ≥75% to ≥85%. Alumina-magnesium-carbon material seat bricks were also tested, but due to mechanical damage caused by the disassembly of the water nozzle, the effect of improving the life of the seat bricks was not obvious.

[0054] (2) To reduce mechanical damage caused by nozzle disassembly, a single nozzle was tested for use in multiple heats to reduce the number of disassembly cycles. First, it was verified that increasing the wall thickness of the fused silica nozzle from 2cm to 4cm significantly improved the casting quality in the first heat. However, when used in the second heat, the bowl area showed significant erosion and the leakage state was unstable. Next, a zirconia nozzle was tested, which showed good erosion resistance and could be used for 2-3 heats. However, due to the unstable manufacturing quality of the manufacturer, further large-scale testing could not be carried out.

[0055] (3) When the above test results were unsatisfactory, hot-state repair of the base bricks was verified. Due to the high temperature of the base bricks, the traditional smearing method resulted in poor adhesion between the repair mortar and the base bricks. Later, a mortar mixture of refractory mortar and silica sol was used for injection repair, which achieved good results and ensured that the service life of the base bricks was consistent with the service life of the liner.

[0056] Adhesive for bonding water outlet bricks and base bricks: The bonding mortar between the sprue and the base brick was initially prepared by mixing mortar powder with an Al2O3 content of ≥75% with silica sol. Because the bond was quite strong, it easily damaged the bottom of the ladle when disassembling using a hydraulic pull-out device. To address this, 7% carbon powder was added to the refractory mortar powder. This ensured both the safety of the bond and improved its performance, thus minimizing damage to the ladle bottom refractory material when pulling out the sprue.

[0057] Precautions for hot-filling bottom injection package 19: The hot disassembly of stopper rod 6 was solved by using a stopper rod magazine to position stopper rod 6 and a custom-made split-arm crane to install the horizontal arm 5 of the bottom injection pot 19. The hot disassembly of the sprue was solved by using a sprue pull-out device and a sprue installation machine. The maintenance of the bedding brick was solved by using a hot grouting repair device. The hot-filling process of the bottom injection pot is a demanding operation in a high-temperature environment that requires meticulous attention to detail. First, it is necessary to strengthen the inspection and control of the assembly gap between the cross arm 5 and the stopper rod station, and between the cross arm 5 and the bottom injection bag 19 positioning plate 8. If the assembly gap exceeds the requirements, it will affect the alignment and fit between the stopper rod 6 and the nozzle.

[0058] Secondly, care must be taken to protect the sprue during installation, especially when repairing it with grout in the bedding bricks. A cover plate should be used to protect the working surface of the sprue to prevent contamination by refractory mortar. If the working surface of the sprue is contaminated, the contaminants will be washed into the mold by the molten steel during the pouring process.

[0059] Third, during the hot-filling process of the bottom-filling bag 19, the temperature of the bag wall and shell is high. Employees must wear protective clothing during the bag preparation operation to avoid burns.

[0060] Implementation effect verification: The process method and special tooling combination of this embodiment are applied to bottom pouring ladle 19 (railway wheel casting). After conducting 1567 heats of bottom pouring ladle hot charging nozzle and stopper rod process tests, and through a large amount of production practice, a mature bottom pouring ladle hot charging nozzle and stopper rod process has been obtained. That is, after the bottom pouring ladle 19 is poured, the special tooling combination provided in this solution is used to disassemble the nozzle and stopper rod 6 in a hot state, and then install the nozzle and stopper rod 6. Grouting is used to maintain the refractory material at the bottom of the ladle. After a short period of heating and heat preservation, it is reused.

[0061] Economic benefits: Our company has changed from the traditional ambient temperature preparation process for bottom injection 19 pots to a hot preparation process, which has saved a significant amount of energy. At the same time, the preparation cycle has been shortened from over 10 hours to no more than 2 hours, and the number of bottom injection 19 pots turned over has been greatly reduced. The energy consumption and number of bottom injection 19 pots turned over during preparation before and after the improvement in the preparation process are shown in the table below:

[0062] After applying the bottom-filling ladle hot-charging nozzle plug rod process, the power and gas consumption required for bottom-filling ladle 19 preparation has been significantly reduced. Considering the combined consumption of refractory materials, power, and gas, this alone reduces production costs by approximately 100 yuan per heat. Based on an annual steelmaking capacity of 6,000 heats (2024 data), this process can reduce production costs by more than 600,000 yuan annually, demonstrating significant economic benefits.

[0063] Example 2 In this embodiment, the structure of the sprue installation machine differs from that in Embodiment 1, specifically: The sprue installation machine includes a mounting base, a drive unit, and a sprue positioning shaft 15. The drive unit adopts a hydraulic cylinder 12 or a linear motor and is mounted on the mounting base. The output end of the drive unit is connected to the sprue positioning shaft 15. The drive unit pushes the sprue positioning shaft 15 to install the sprue on the sprue positioning shaft 15 into the corresponding hole in the base brick, thus completing the assembly of the sprue.

[0064] Beneficial effects: The bottom-filling hot-filling nozzle plug rod process and special tooling assembly of the present invention have the following advantages compared with the prior art: 1. Significantly reduced energy consumption: After the bottom injection package 19 is poured, it does not need to be cooled to room temperature. Replacement and maintenance can be completed directly in the hot state before 800℃, avoiding heat waste caused by repeated cooling and heating, significantly saving energy consumption such as natural gas and electricity, which is in line with the "dual carbon" policy orientation.

[0065] 2. Significantly improved packing efficiency: The packing cycle has been shortened from more than 10 hours to less than 2 hours, greatly reducing the packing time, reducing the number of bottom injection packs 19, saving production space and equipment capital, and improving production continuity.

[0066] 3. Reduced refractory material wear: It avoids the repeated high-low-high temperature shocks experienced by the bottom injection liner 19, which extends the service life of refractory materials such as lining and seat bricks, reduces the cost of refractory material replacement and maintenance, and reduces carbon emissions.

[0067] 4. Solving the challenges of hot operation: The special tooling combination (stopper bar library, stopper bar lifting equipment, sprue pulling device, sprue installation machine, etc.) specifically solves the technical problems in hot operation such as high temperature protection, insufficient centering accuracy, difficulty in sprue disassembly, and easy damage to refractory materials, ensuring the smooth implementation of hot replacement and maintenance, and improving operational reliability and casting quality.

[0068] 5. High practicality: The process steps are simple and easy to operate. The special tooling combination structure is reasonable and easy to debug. It can be adapted to the existing bottom pouring ladle 19 without the need for major modification of the bottom pouring ladle 19. It is easy to promote and apply, and is suitable for various fields that use bottom pouring ladle 19 for casting, such as railway wheels and engineering machinery castings.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for hot-filling sprue stopper rod in bottom-fill packaging, characterized in that, In the hot state of the bottom injection pot, the stopper rod is pressed onto the nozzle brick using a stopper rod lifting device and the stopper rod head is blocked in the nozzle. The end of the stopper rod lifting device is equipped with a cross arm for connecting the stopper rod. After the previous pouring is completed and before the temperature of the bottom pouring pot wall drops to 800℃, the bottom pouring pot nozzle and stopper rod should be replaced and the nozzle seat bricks should be maintained. After a short period of heating and heat preservation, the bottom pouring pot can be reused. The specific steps include: S1. Hot replacement of stopper rod: The stopper rod is removed from the horizontal arm of the bottom injection pot press by using the stopper rod lifting equipment. The stopper rod is then transferred to the corresponding stopper rod storage station and locked. The new stopper rod is then assembled onto the horizontal arm. The new stopper rod is installed and adjusted according to the pre-marked position in the stopper rod storage station. The new stopper rod is then reinstalled into the bottom injection pot by the stopper rod lifting equipment. After the stopper rod head is plugged into the water inlet, the horizontal arm is locked and positioned. S2. Hot replacement of nozzles: The old nozzles on the bottom injection bag are removed by using a nozzle pulling device. Then, the new nozzles are installed and fixed after being aligned with the centering brick hole by a nozzle installation machine. The outer wall of the new nozzles is coated with refractory mortar. After installation, a nozzle cover plate is installed to seal the nozzles. S3. Hot maintenance of seat bricks: Hot repair of seat bricks is carried out by grouting. After completion, the bottom grouting pot is briefly heated and kept warm to complete the preparation of the pot.

2. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, In step S1, the stopper rod magazine is set up one-to-one with the bottom injection package. One horizontal arm corresponds to only one bottom injection package and one stopper rod magazine station. The stopper rod magazine is pre-calibrated after the bottom injection package is built and the water inlet is installed at room temperature. The horizontal arm is locked on the positioning plate, the stopper rod is installed and adjusted to the optimal position, and the stopper rod head position is calibrated in the stopper rod magazine and the calibration fixture is locked.

3. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, In step S2, the sprue pulling device includes a hydraulic cylinder and a pulling column. The output end of the hydraulic cylinder is connected to the pulling column. An eccentric clamping plate is hinged to the end of the pulling column, and a limiting part is provided on the pulling column to prevent the eccentric clamping plate from rotating excessively. The eccentric clamping plate has a retracted state and an open state on the pulling column. The disassembly operation of the sprue pulling device includes: first, laying the bottom injection bag horizontally so that the sprue hole is in a horizontal state; then, adjusting the eccentric clamping plate on the pulling column to a closed state and passing it horizontally through the sprue hole; when the eccentric clamping plate exceeds the sprue hole, it falls under the action of gravity and is in an open state; then, the hydraulic cylinder is activated to pull the sprue through the eccentric clamping plate to complete the sprue pulling out.

4. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, In step S2, the sprue installation machine includes a base, a drive unit, a linkage cantilever, and a sprue positioning shaft. The drive unit is mounted on the base, and the end of the drive unit is connected to the sprue positioning shaft via the linkage cantilever. When installing the sprue, place the bottom injection bag horizontally, place the new sprue on the sprue positioning shaft and align it with the hole in the base brick, and then drive the sprue positioning shaft through the drive component to push the sprue into the hole in the base brick, thus completing the assembly of the sprue.

5. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, In step S3, the grouting material for the hot repair of the seat brick is a slurry made of refractory mortar and silica sol.

6. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, In step S2, the bonding mortar between the new water inlet and the base brick is a mixture of refractory mortar powder with an Al2O3 content ≥75%, silica sol, and carbon powder, wherein the carbon powder is added in a proportion of 5% to 9%.

7. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, The sprue is made of fused silica and has a wall thickness of 3-5 cm.

8. The bottom-filling hot-filling nozzle plug rod process method according to claim 1, characterized in that, The bottom lining of the injection pot is constructed with high-alumina bricks with an Al2O3 content of ≥75%, and the base bricks are high-alumina bricks or aluminum-magnesium-carbon materials with an Al2O3 content of ≥85%.

9. The bottom-fill package hot-fill nozzle plugging process method according to claim 1, characterized in that, In the aforementioned process, the sprue and stopper are replaced once for each batch of casting to ensure that the sprue and stopper are in optimal condition free from corrosion and adsorption during casting.

10. A special tooling assembly for implementing the bottom-filling hot-filling nozzle plug rod process of any one of claims 1-9, characterized in that, This includes a stopper rod magazine, stopper rod lifting equipment, sprue pulling device, sprue installation machine, and hot grouting repair device for seat bricks, all equipped with a one-to-one matching bottom grouting package. The stopper rod magazine includes a positioning base, a positioning plate, and a stopper rod head positioner. The positioning base is provided with the positioning plate, and the positioning plate is provided with a positioning pin hole. The cross arm is provided with a positioning pin, and by inserting the positioning pin into the positioning pin hole, the stopper rod head on the cross arm is placed on the stopper rod head positioner to complete the locking and storage of the stopper rod.

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