Aluminum tube semi-continuous casting device with intelligent core breaking and method

Abstract

The application discloses an aluminum pipe semi-continuous casting device with intelligent core stripping and a method, and relates to the technical field of light alloy casting. The device comprises a rack, a traction system for pulling an aluminum pipe blank, a crystallizer vibration system, a core mold vibration system, a chute unit for preheating a flow guide molten metal, a bearing plate, a bearing base, and a feedback control system for the vibration of the crystallizer and the core mold. The device adds the functions of the vibration of the crystallizer and the core rod and the mechanical sensor feedback control function on the basis of the conventional semi-continuous casting device. The crystallizer and the core rod are vibrated through the mechanical sensor feedback control to avoid core holding and efficiently strip the core, thereby ensuring the continuous casting. The device solves the problem that the aluminum pipe is difficult to strip the core from the core mold during the semi-continuous casting process, ensures the continuity of the casting, reduces the occurrence of casting accidents, and improves the production efficiency of the aluminum pipe casting.

Description

Technical Field

[0001] This invention relates to the field of lightweight alloy metal casting technology, and in particular to a semi-continuous casting apparatus and method for aluminum tubes with intelligent core removal. Background Technology

[0002] Aluminum alloys are widely used in shipbuilding, aerospace, and automotive industries due to their advantages such as light weight, high specific strength, and good corrosion resistance. Thick-walled aluminum tubes refer to tubes with a wall thickness of 5-100mm or more, and can be used to manufacture parts such as missile casings, missile combustion chambers, and aircraft engine casings. Currently, extrusion is the commonly used production method for thick-walled aluminum tubes. Extrusion can improve the material structure and enhance the mechanical properties of aluminum tubes; however, it results in uneven metal deformation, rapid die wear, and a significant amount of metal waste. Compared to extrusion, semi-continuous casting of thick-walled aluminum tubes offers higher material utilization, lower energy consumption, and lower manufacturing costs. Using extrusion as a post-processing step in semi-continuous casting of thick-walled aluminum tubes can shorten the process flow and improve metal utilization.

[0003] Semi-continuous casting of thick-walled aluminum tubes involves pouring molten aluminum alloy through a chute into a space consisting of a crystallizer, a mandrel, and a sprue. The aluminum tube is then formed through cooling in the crystallizer and mandrel. During the semi-continuous casting process, the cooling and shrinkage of the inner wall of the aluminum tube can easily cause it to seize up to the mandrel, leading to discontinuous casting or even equipment damage. To address this issue, the mandrel inside the crystallizer is typically tapered, or casting process parameters are adjusted to prevent this problem. However, these conventional methods suffer from uncertainty in their applicability due to the uncertain relationship between the mandrel tapering, the shrinkage of the inner wall of the aluminum tube, and the clamping force of the inner wall on the mandrel. Therefore, a semi-continuous vibration casting device and production method for thick-walled aluminum tubes are proposed. Summary of the Invention

[0004] To address the problem of aluminum tubes clinging to the casting core mold during semi-continuous casting of thick-walled aluminum tubes due to cooling, this invention provides a semi-continuous vibration casting device for thick-walled aluminum tubes and a method for force measurement and feedback control during vibration demolding. This avoids the aluminum tube clinging to the core mold during casting, reduces the occurrence of accidents, and ensures the continuity of casting.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] This invention provides a semi-continuous aluminum tube casting device with intelligent core removal, comprising a frame, a traction system, a crystallizer vibration system, a core mold vibration system, a chute unit, a load-bearing plate, and a load-bearing base; the load-bearing plate is disposed on the top of the frame; the crystallizer vibration system and the core mold vibration system are disposed on the load-bearing plate, with the core mold vibration system located above the crystallizer vibration system; the chute unit is disposed on the load-bearing plate and located between the crystallizer vibration system and the core mold vibration system; the traction system is disposed below the load-bearing plate; the load-bearing base is disposed at the bottom of the frame; the traction system is used to traction the aluminum tube blank; the chute unit is used to preheat and guide the molten metal; and the load-bearing plate is provided with material passage holes.

[0007] Optionally, the traction system includes a lower crossbeam, module positioning blocks, columns, a lead screw module, a proximity sensor, a motor support, a traction motor, a spindle tray, connecting bolts, a traction tension / compression sensor, and a spindle tray bracket. The two ends of the lower crossbeam are connected to the lower part of the frame. A lead screw module is mounted on the lower crossbeam, and the lead screw module is connected to one end of the spindle tray bracket. The spindle tray is mounted on the other end of the spindle tray bracket. A column is positioned above each end of the lower crossbeam, and a proximity sensor is mounted on the column closest to the lead screw module. A motor support is positioned above the load-bearing plate, and the traction motor is mounted on the motor support. The output shaft of the traction motor is connected to the lead screw module. A module positioning block is positioned at the top and bottom of the lead screw module. The traction tension / compression sensor is positioned between the spindle tray and the spindle tray bracket. The spindle tray and the spindle tray bracket are connected by the connecting bolts.

[0008] Optionally, the crystallizer vibration system includes a dual-shaft output reducer, a crystallization vibration motor, a reversing reducer, a crystallization vibration bushing, a shaft, a crystallizer, a vibration platform, an eccentric wheel unit, support bolts, a positioning guide unit, and a crystallization laser displacement sensor. The crystallization vibration motor is located on one side of the load-bearing plate, and its output shaft is connected to the input end of the dual-shaft output reducer. The output ends of the dual-shaft output reducer are respectively connected to one end of one of the reversing reducers, and the other end of the reversing reducer is connected to the eccentric wheel unit. Two eccentric wheel units are located on either side of the material through-hole. Two positioning guide units are arranged around the material through-hole. The crystallizer is mounted on the positioning guide unit. The crystallization laser displacement sensor is located above and to the side of the crystallizer. The crystallization laser displacement sensor is used to detect the vibration amplitude of the crystallizer. Multiple support bolts are arranged around the material through-hole. A crystallization vibration bushing, a shaft, and a crystallization vibration bushing are sequentially arranged between the other end of the reversing reducer and the eccentric wheel unit.

[0009] Optionally, the positioning guide unit includes a positioning support, a positioning sleeve, and a copper sleeve; the positioning support is threadedly connected to the load-bearing plate, the positioning sleeve is threadedly connected to the bottom of the vibration platform and coaxial with the positioning support, the copper sleeve is built into the positioning sleeve and mates with the positioning support, the copper sleeve and the positioning sleeve have an interference fit, and the copper sleeve and the positioning support have a clearance fit; the eccentric wheel unit includes a vibration sleeve, a vibration sleeve end cap, bearing I, an eccentric shaft I, two bearings II, two bearing supports, and two bearing end caps; bearing I is built into the cavity formed by the vibration sleeve and the vibration sleeve end cap, the eccentric shaft I mates with the inner hole of bearing I, the vibration sleeve is located between the two bearing supports, and bearing II is built into the sealed space formed by the bearing supports and the bearing end caps. The fit between bearing I and the vibration sleeve is an interference fit; the fit between bearing II and the bearing support is an interference fit; the fit between eccentric shaft I and bearings I and II is a clearance fit; the bearing support is threadedly connected to the load-bearing plate; the crystallizer includes an outer mold and an inner mold, and a cooling water inlet / outlet is provided on the outer mold; small water outlet holes are evenly arranged on the bottom chamfer of the inner mold; an O-ring seal is provided at the top mating point between the outer mold and the inner mold; a groove is provided on the top of the crystallizer, and an annular heat-insulating material is placed in the groove as a heat-generating top; the dual-shaft output reducer is connected to the reversing reducer and the eccentric wheel unit through a bushing; the eccentricity of eccentric shaft I in the eccentric wheel unit is 2-4mm, and the eccentricity of eccentric shaft II is 2-4mm.

[0010] Optionally, the core mold vibration system includes a support beam, a support crossbeam, a motor bracket, a core mold vibration motor, a reducer, a core mold vibration bushing, an eccentric shaft, a hinge sleeve unit, a sliding bearing seat, a sliding bearing gasket, a hinge seat, a core mold laser displacement sensor, a core mold vibration tension / compression sensor, a vibration slider, a flange linear bearing, a mandrel, a heat insulation ring, and a core mold; a support beam is respectively provided on both sides of the load-bearing plate, and a support crossbeam is provided between the tops of the two support beams; a motor bracket is provided on the support crossbeam, and the core mold vibration motor is provided on the motor bracket; the core mold vibration... The output shaft of the motor is connected to one end of the reducer, and the other end of the reducer is connected to the core mold vibration sleeve. A sliding bearing seat is provided at each end of the core mold vibration sleeve. A hinge sleeve unit is provided in the middle of the core mold vibration sleeve. The hinge sleeve unit is connected to the hinge seat. Below the hinge seat, in sequence, are the core mold laser displacement sensor, the core mold vibration tension / compression sensor, the vibration slider, the flange linear bearing, the mandrel, the heat insulation ring, and the core mold. A sliding bearing gasket is provided between the sliding bearing seat and the top of the motor bracket.

[0011] Optionally, in the mandrel vibration system, the eccentric shaft and the reducer are connected via the mandrel vibration bushing. The eccentric shaft and the inner hole of the sliding bearing support are in clearance fit. The hinge sleeve unit and the hinge seat are connected via a pin. The tension / compression sensor is threaded between the hinge seat and the vibration slider. The vibration slider and the flange linear bearing are in clearance fit. The flange linear bearing is threaded onto the support beam. The mandrel and the mandrel are threaded together, and a high-temperature resistant O-ring is provided at the bottom of the threaded fit. Cooling water for cooling molten metal flows through the mandrel and the mandrel. The mandrel has a mandrel inlet / outlet water port.

[0012] Optionally, both the crystallizer and the core mold are made of aluminum alloy. The inner diameter of the crystallizer is 80-140mm, the outer diameter of the core mold is 40-80mm, the angle between the axis of the water holes evenly arranged on the bottom chamfer of the inner mold of the crystallizer and the horizontal direction is 45°-60°, the taper of the core mold is 1°-2°, and the crystallizer and the core mold are coaxial.

[0013] Optionally, the chute unit includes insulation material inside the chute shell, a cast copper heating plate located below the chute shell to preheat the chute, a chute support located on and connected to the frame, and insulation material located between the cast copper heating plate and the chute support to provide thermal insulation.

[0014] The present invention also provides a casting method for a semi-continuous aluminum tube casting device with intelligent core removal, comprising the following steps:

[0015] 1) Lift the traction plate in the traction system to the bottom of the core mold in the crystallizer vibration system and make contact with the core mold. Then, pass cold water into the crystallizer and the core mold until the cooling water flows out from the crystallizer nozzle and the core rod nozzle. At the same time, preheat the chute unit to 400-600℃.

[0016] 2) Molten aluminum is injected into the chute unit and enters the crystallizer through the chute unit. The temperature of the molten aluminum is 700-720℃. When the liquid level of the molten metal in the crystallizer reaches the specified height, the traction system is started to start casting. At the same time, the crystallizer vibration system is turned on. If core seizure is about to occur during the aluminum tube casting process, the force signals fed back by the traction tension and compression sensor and the core mold vibration tension and compression sensor are sent to the CPU module of the PLC to control the core mold vibration motor to rotate through the servo driver, thereby driving the core rod to vibrate to avoid core seizure.

[0017] 3) When the traction plate in the traction system moves downward to the designated position, stop injecting aluminum liquid into the chute unit until the aluminum alloy ingot is completely pulled out of the crystallizer, turn off the crystallizer vibration system, the core mold vibration system and the cooling water, and stop casting.

[0018] Optionally, the pipe demolding method includes the following steps:

[0019] When the actual axial force between the tube and the mandrel is less than the critical value for mandrel clamping, the semi-continuous vibration casting equipment for aluminum tubes can operate normally. When the actual axial force between the tube and the mandrel is greater than the critical value for mandrel clamping, mandrel clamping occurs. The PLC will process the signal transmitted by the traction and compression sensors and send out first motion feedback and second motion feedback. The first motion feedback starts the mandrel vibration system, and the mandrel drives the mandrel to vibrate up and down. The second motion feedback stops the descent of the mandrel guide plate. The initial position of the mandrel is uncertain, and the mandrel can move in two directions: upward or downward.

[0020] 1) The mandrel moves upward;

[0021] When the mandrel moves upward, the actual parameters of the traction and compression sensor are less than the theoretical parameters, and the position where the pipe falls off is divided into two types: above the initial position and below the initial position;

[0022] ① When the pipe falls off above the initial position, the pipe has an initial velocity and acceleration. The actual parameter of the traction and tension sensor is greater than the theoretical parameter and the actual parameter of the traction and tension sensor is equal to the theoretical parameter for a short time. The PLC will receive the signal transmitted by the traction and tension sensor and send the first motion feedback and the second motion feedback. The first motion feedback causes the mandrel vibration system to stop working, and the second motion feedback causes the dart plate to start descending. When the pipe falls off above the initial position, the following command is executed when the pipe falls off at the initial position.

[0023] ② When the pipe falls off below the initial position, and the actual parameter of the traction and tension sensor is greater than the theoretical parameter and does not change within a short period of time, the PLC receives the signal transmitted by the traction and tension sensor and sends out the second motion feedback. The second motion feedback causes the bobbin to descend by a height h, and the maximum value of h cannot exceed 1 / 5-1 / 3 of the liquid level. When the actual parameter of the traction and tension sensor is equal to the theoretical parameter and does not change within a certain period of time, the PLC receives the signal transmitted by the traction and tension sensor and sends out the first motion feedback and the second motion feedback. The first motion feedback causes the core mold vibration system to stop working, and the second motion feedback causes the bobbin to start descending. When the pipe has not fallen off below the initial position, the command to make the pipe fall off above the initial position is executed.

[0024] 2) The mandrel moves downwards.

[0025] When the mandrel moves downward, the position where the tube falls off is either below the initial position or above the initial position, and the motion feedback is the same as when the mandrel moves upward.

[0026] The present invention achieves the following technical effects compared to the prior art:

[0027] (1) Compared with conventional aluminum tube semi-continuous casting equipment, the equipment of the present invention adds the vibration function of crystallizer and mandrel on the basis of conventional aluminum tube semi-continuous casting, which makes the surface quality of aluminum tube better and the grains finer. In particular, the grain refinement effect is better for tube blanks with a small ratio of inner and outer diameters. For tube blanks with a high degree of alloying, it can reduce the formation of segregation nodules on the surface of the tube blank and improve the surface quality of the tube blank.

[0028] (2) The present invention adds a mechanical sensor feedback control function to the equipment for conventional aluminum tube semi-continuous casting. It can control the vibration of the mandrel according to the mechanical signal measured by the actual mechanical sensor and the feedback to prevent core seizing and achieve efficient demolding. Attached Figure Description

[0029] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0030] Figure 1 A three-dimensional structural diagram of a semi-continuous vibration casting equipment for thick-walled aluminum tubes;

[0031] Figure 2 This is a schematic diagram of the three-dimensional structure of the crystallizer vibration system;

[0032] Figure 3 A three-dimensional structural diagram of the support and positioning components in the crystallizer vibration system;

[0033] Figure 4 This is a schematic diagram of the three-dimensional structure of the mandrel vibration system;

[0034] Figure 5 This is a schematic diagram of the three-dimensional structure of the traction system;

[0035] Figure 6 A mechanical schematic diagram of the mandrel, tube, and spool plate as a whole;

[0036] Figure 7 This is a schematic diagram of the mechanical properties of the mandrel.

[0037] Figure 8 A mechanical schematic diagram of the pipe and the spool plate as a whole;

[0038] Figure 9 This is a schematic diagram of the mandrel motion control system.

[0039] Figure 10 Mind map of the core removal process for the core rod.

[0040] 1. Frame; 2. Traction system; 3. Crystallizer vibration system; 4. Core mold vibration system; 5. Sluice box unit; 6. Load-bearing plate; 7. Load-bearing base;

[0041] 201. Lower crossbeam; 202. Module positioning block; 203. Column; 204. Lead screw module; 205. Proximity sensor; 206. Motor support; 207. Traction motor; 208. Die-drawing disc; 209. Connecting bolt; 210. Traction tension / compression sensor; 211. Die-drawing disc bracket;

[0042] 301. Dual-shaft output reducer; 302. Crystallizing vibration motor; 303. Reversing reducer; 304. Crystallizing vibration bushing; 305. Shaft; 306. Crystallizer; 307. Vibration platform; 308. Eccentric wheel unit; 309. Support bolt; 310. Positioning guide unit; 311. Crystallizing laser displacement sensor;

[0043] 401. Support beam; 402. Support beam; 403. Motor bracket; 404. Core mold vibration motor; 405. Reducer; 406. Core mold vibration bushing; 407. Eccentric shaft; 408. Hinge sleeve unit; 409. Sliding bearing seat; 410. Sliding bearing gasket; 411. Hinge seat; 412. Core mold laser displacement sensor; 413. Core mold vibration tension / compression sensor; 414. Vibration slider; 415. Flange linear bearing; 416. Mandrel; 417. Heat insulation ring; 418. Core mold. Detailed Implementation

[0044] 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. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] like Figures 1 to 5 As shown, this embodiment provides a semi-continuous aluminum tube casting device with intelligent core removal, including a frame 1, a traction system 2, a crystallizer vibration system 3, a core mold vibration system 4, a chute unit 5, a load-bearing plate 6, and a load-bearing base 7; the load-bearing plate 6 is provided on the top of the frame 1; the crystallizer vibration system 3 and the core mold vibration system 4 are provided on the load-bearing plate 6, and the core mold vibration system 4 is located above the crystallizer vibration system 3; the chute unit 5 is provided on the load-bearing plate 6 and located between the crystallizer vibration system 3 and the core mold vibration system 4; the traction system 2 is provided below the load-bearing plate 6; the load-bearing base 7 is provided at the bottom of the frame 1; the traction system 2 is used to traction the aluminum tube billet; the chute unit 5 is used to preheat and guide the molten metal; the load-bearing plate 6 is provided with material passage holes.

[0046] In this specific embodiment, the traction system 2 includes a lower crossbeam 201, a module positioning block 202, a column 203, a lead screw module 204, a proximity sensor 205, a motor support 206, a traction motor 207, a spindle tray 208, connecting bolts 209, a traction tension / compression sensor 210, and a spindle tray bracket 211; both ends of the lower crossbeam 201 are connected to the lower part of the frame 1, and a lead screw module 204 is provided on the lower crossbeam 201. The lead screw module 204 is connected to one end of the spindle tray bracket 211, and a spindle tray 208 is provided on the other end of the spindle tray bracket 211; the lower crossbeam 201... A column 203 is installed above each of the two ends of the 1. A proximity sensor 205 is installed on the column 203 near the lead screw module 204. A motor support 206 is installed above the load-bearing plate 6. A traction motor 207 is installed on the motor support 206. The output shaft of the traction motor 207 is connected to the lead screw module 204. A module positioning block 202 is installed at the top and bottom of the lead screw module 204. A traction tension sensor 210 is installed between the ingot dummy plate 208 and the ingot dummy plate bracket 211. The ingot dummy plate 208 and the ingot dummy plate bracket 211 are connected by connecting bolts 209.

[0047] The crystallizer vibration system 3 includes a dual-shaft output reducer 301, a crystallization vibration motor 302, a reversing reducer 303, a crystallization vibration bushing 304, a shaft 305, a crystallizer 306, a vibration platform 307, an eccentric wheel unit 308, support bolts 309, a positioning guide unit 310, and a crystallization laser displacement sensor 311. The crystallization vibration motor 302 is located on one side of the load-bearing plate 6, and its output shaft is connected to the input end of the dual-shaft output reducer 301. The output ends of the dual-shaft output reducer 301 are each connected to one end of a reversing reducer 303. The other end is connected to the eccentric wheel unit 308 for transmission; the two eccentric wheel units 308 are located on both sides of the material through hole; two positioning guide units 310 are arranged around the material through hole; the crystallizer 306 is arranged on the positioning guide unit 310; a crystallization laser displacement sensor 311 is arranged on the upper side of the crystallizer 306; the crystallization laser displacement sensor 311 is used to detect the vibration amplitude of the crystallizer 306; multiple support bolts 309 are arranged around the material through hole; between the other end of the reversing reducer 303 and the eccentric wheel unit 308, a crystallization vibration bushing 304, a shaft 305 and a crystallization vibration bushing 304 are arranged in sequence.

[0048] The positioning and guiding unit 310 includes a positioning support, a positioning sleeve, and a copper sleeve. The positioning support is threaded onto the load-bearing plate 6, the positioning sleeve is threaded onto the underside of the vibration platform 307 and coaxial with the positioning support, and the copper sleeve is built into the positioning sleeve and mates with the positioning support. The copper sleeve and the positioning sleeve have an interference fit, and the copper sleeve and the positioning support have a clearance fit. The eccentric wheel unit 308 includes a vibration sleeve, a vibration sleeve end cap, bearing I, an eccentric shaft I, two bearings II, two bearing supports, and two bearing end caps. Bearing I is built into the cavity formed by the vibration sleeve and the vibration sleeve end cap, and the eccentric shaft I mates with the inner hole of bearing I. The vibration sleeve is located between the two bearing supports, and bearing II is built into the sealed space formed by the bearing supports and the bearing end caps. Bearing I has an interference fit with the vibration sleeve, and bearing II has a clearance fit with the shaft. The fit between the bearings is an interference fit, while the fit between the eccentric shaft I and bearings I and II is a clearance fit. The bearing supports are threaded onto the load-bearing plate 6. The crystallizer 306 includes an outer mold and an inner mold. Cooling water inlet and outlet are provided on the outer mold. Small water outlet holes are evenly arranged on the bottom chamfer of the inner mold. An O-ring is provided at the top of the outer mold and the inner mold. A groove is provided on the top of the crystallizer 306, and an annular heat-insulating material is placed in the groove as a heat-generating top. The dual-shaft output reducer is connected to the reversing reducer 303 and the eccentric wheel unit 308 through a bushing. The eccentricity of eccentric shaft I and eccentric shaft II in the eccentric wheel unit 308 is 2.0 mm.

[0049] The core mold vibration system 4 includes a support beam 401, a support crossbeam 402, a motor bracket 403, a core mold vibration motor 404, a reducer 405, a core mold vibration bushing 406, an eccentric shaft 407, a hinge sleeve unit 408, a sliding bearing seat 409, a sliding bearing gasket 410, a hinge seat 411, a core mold laser displacement sensor 412, a core mold vibration tension / compression sensor 413, a vibration slider 414, a flange linear bearing 415, a mandrel 416, a heat insulation ring 417, and a core mold 418. A support beam 401 is provided on each side of the load-bearing plate 6, and a support crossbeam 402 is provided between the tops of the two support beams 401. A motor bracket 403 is provided on the support crossbeam 402, and a motor bracket 403 is provided on the motor bracket 403. The device includes a core mold vibration motor 404; the output shaft of the core mold vibration motor 404 is connected to one end of a reducer 405, and the other end of the reducer 405 is connected to a core mold vibration bushing 406. A sliding bearing seat 409 is provided at each end of the core mold vibration bushing 406; a hinge sleeve unit 408 is provided in the middle of the core mold vibration bushing 406; the hinge sleeve unit 408 is connected to a hinge seat 411, and a core mold laser displacement sensor 412, a core mold vibration tension and compression sensor 413, a vibration slider 414, a flange linear bearing 415, a core rod 416, a heat insulation ring 417, and a core mold 418 are arranged sequentially below the hinge seat 411; a sliding bearing gasket 410 is provided between the sliding bearing seat 409 and the top of the motor bracket 403.

[0050] In the vibration system of mandrel 416, the eccentric shaft 407 and the reducer 405 are connected by the mandrel vibration sleeve 406. The eccentric shaft 407 and the inner hole of the sliding bearing support are in clearance fit. The hinge sleeve unit 408 and the hinge seat 411 are connected by a pin. The tension and compression sensor is connected between the hinge seat 411 and the vibration slider 414 by a thread. The vibration slider 414 and the flange linear bearing are in clearance fit. The flange linear bearing is threaded to the support beam 402. The mandrel 416 and the mandrel 418 are connected by a thread and a high-temperature resistant O-ring is provided at the bottom of the threaded fit. Cooling water for cooling the molten metal flows through the mandrel 416 and the mandrel 418. The mandrel 416 is provided with a mandrel 416 inlet and outlet water port.

[0051] Both the crystallizer 306 and the core mold 418 are made of aluminum alloy. The inner diameter of the crystallizer 306 is 140mm, and the outer diameter of the core mold 418 is 80mm. The water holes evenly arranged on the bottom chamfer of the inner mold of the crystallizer 306 have an angle of 60° with the horizontal direction. The core mold 418 has a taper of 1°, and the crystallizer 306 and the core mold 418 are coaxial.

[0052] The chute unit 5 includes insulation material inside the chute shell, a cast copper heating plate located below the chute shell that preheats the chute, a chute support located on and connected to the frame 1, and insulation material located between the cast copper heating plate and the chute support that provides thermal insulation.

[0053] like Figures 6 to 8 The diagram shows the forces exerted by the tube on the mandrel 418 during normal operation (f1), the forces exerted by the mandrel 418 on the tube during normal operation (f'1), the frictional force exerted by the crystallizer 306 on the tube during normal operation (f2), and G. 管材 Material quality, F1 core mold vibration tension and compression sensor 413 reading, F2 traction tension and compression sensor 210 reading, F'2 traction tension and compression sensor 210 reading during normal operation, G 引锭盘 208 mass of the ingot tray, G 芯棒 mandrel 416 quality (including mandrel 418), f c When core seizure occurs, the tube exerts an axial force on the mandrel 418.

[0054] G 管材 It can be calculated based on the drop height h of the derrick:

[0055] G 管材 =G 截面 ×h (1)

[0056] The shear stress on the wall of the mandrel 418 caused by the solution is negligible. Figure 6 By performing a stress analysis on the mandrel 416 (including the mandrel 418), the tube, and the dummy bar 208 as a whole, we can obtain the following results:

[0057] G 引锭盘 +G 管材 +G 芯棒 =F1+F2+f2 (2)

[0058] according to Figure 7 Force analysis of mandrel 416 (including mandrel 418) yields the following results:

[0059] F1 = G 芯棒 +f1 (3)

[0060] Substituting equation (3) into equation (2):

[0061] f1 = G 引锭盘 +G 管材 -F2-f2 (4)

[0062] When the core is bound, f1 ≥ f2, and f2 can be ignored. Therefore, the above formula can be expressed as:

[0063] f1 = G 引锭盘 +G 管材 -F2 (5)

[0064] according to Figure 8 By performing a stress analysis on the pipe and the dummy disc 208 as a whole, we can obtain the following results:

[0065] F2 = G引锭盘 +G 管材 -f'1 - f2 = G 引锭盘 +G 管材 -f'1 = F'2 (6)

[0066] When core holding occurs, the aluminum alloy solidifies and shrinks. The reduction in the inner diameter of the pipe is calculated through the linear shrinkage rate of the aluminum alloy as the mating interference δ, and the relationship between the mating surface pressure p and the mating interference δ min relationship Using f c = p × S × μ 静 , the axial force f between the pipe and the mandrel 416 is obtained c , and f can be determined by setting the corresponding mating interference c the magnitude of the core holding critical value;

[0067] Such as Figure 9 the schematic diagram of the mandrel 416 motion control system shown Figure 10 shown is the mind map of the mandrel 416 core removal. When f1 < f c , the pipe casting can proceed normally. When f1 ≥ f c , core holding occurs. The PLC will process the signal F2 transmitted by the traction tension sensor 210 and emit the first motion feedback and the second motion feedback. The first motion feedback makes the core die vibration motor 404 drive the eccentric shaft 407 to rotate, and the mandrel 416 vibrates up and down. The second motion feedback makes the traction motor 207 stop rotating and the dummy bar 208 stop descending. The initial position of the mandrel 416 is uncertain, and there are two directions for the mandrel 416 to start moving: upward movement and downward movement

[0068] 1) The mandrel 416 moves upward

[0069] When the mandrel 416 moves upward, F2 < F'2. The positions where the pipe falls off are divided into two types: above the initial position and

[0070] below the initial position

[0071] ① When the pipe falls off position is above the initial position, the pipe has an initial velocity and acceleration, F2 > F'2 and F2 = F'2 in a short time. The PLC receives the F2 signal emitted by the traction tension sensor 210 and emits the first motion feedback and the second motion feedback. The first motion feedback makes the core die vibration motor 404 drive the eccentric shaft 407 to stop rotating, and the second motion feedback makes the traction motor 207 start rotating and the dummy bar 208 start descending. When the pipe does not fall off above the initial position, the mandrel 416 continues to vibrate, and it is judged whether to execute the command that the pipe falls off position is below the initial position

[0072] ② When the pipe falls below the initial position, and F2 > F'2 does not change within a short time, and the actual parameter of the traction and tension sensor is 1.2 times the theoretical parameter, the PLC receives the F2 signal emitted by the traction and tension sensor 210 and emits the second motion feedback. The second motion feedback causes the guide rod to descend by a certain height. Furthermore, the maximum value of h cannot exceed 1 / 4 of the liquid level height. When F2 = F'2 and does not change within a certain period of time, the PLC receives the F2 signal emitted by the pressure sensor 210 and emits the first motion feedback and the second motion feedback. The first motion feedback causes the mandrel vibration motor 404 to stop rotating the eccentric shaft 407. The second motion feedback causes the traction motor 207 to start rotating and the dart plate 208 to start descending. When the tube is below the initial position and has not fallen off, the mandrel 416 continues to vibrate. It is determined whether to execute the command that the tube falls off above the initial position.

[0073] 2) Core rod 416 moves downwards

[0074] When the mandrel 416 moves downward, the position where the tube falls off is divided into two types: below the initial position and above the initial position. The motion feedback is the same as when the mandrel 416 moves upward.

[0075] The process of producing thick-walled aluminum tubes using a semi-continuous vibration casting equipment for thick-walled aluminum tubes in this invention is as follows:

[0076] 1) Lift the ingot plate 208 in the traction system 2 to the bottom of the core mold 418 in the crystallizer vibration system 3. When it gets close to the proximity sensor 205, stop moving. Then, pass cold water into the crystallizer 306 and the core mold 418 until the cooling water flows out from the water outlet of the crystallizer 306 and the water outlet of the core rod 416. At the same time, preheat the chute unit 5 to 500°C.

[0077] 2) Molten aluminum is injected into the chute unit 5. The molten aluminum enters the crystallizer 306 through the chute unit 5. The temperature of the molten aluminum is 700℃. When the liquid level of the molten metal in the crystallizer 306 reaches the specified height, the traction system 2 is started to start casting. At the same time, the crystallizer vibration system 3 is turned on. If core seizure is about to occur during the aluminum tube casting process, the force signals fed back by the traction tension and compression sensor 210 and the core mold vibration tension and compression sensor 413 are sent to the CPU module of the PLC to control the core mold vibration motor 404 to rotate through the servo driver, thereby driving the core rod 416 to vibrate to avoid core seizure.

[0078] 3) When the ingot guide plate 208 in the traction system 2 moves downward to the designated position, stop injecting aluminum liquid into the chute unit 5 until the aluminum alloy ingot is completely pulled out of the crystallizer 306, turn off the crystallizer vibration system 3 and the core mold vibration system 4 as well as the cooling water, and stop casting.

[0079] The difference between the semi-continuous vibration casting method and equipment for thick-walled aluminum tubes of the present invention and the existing devices is that the equipment of the present invention adds the vibration function of the crystallizer 306 and the mandrel 416 to the conventional semi-continuous casting of aluminum tubes, which makes the surface quality of the aluminum tube better and the grains finer. In particular, the grain refinement effect is better for casting tube blanks with a small ratio of inner to outer diameter. For casting tube blanks with a high degree of alloying, it can reduce the formation of segregation nodules on the surface of the tube blank and improve the surface quality of the tube blank.

[0080] The difference between the semi-continuous vibration casting method and equipment for thick-walled aluminum tubes of the present invention and the existing devices is that the present invention adds a mechanical sensor feedback control system to the conventional semi-continuous casting equipment for aluminum tubes. The mechanical signal actually measured by the mechanical sensor during the casting process is used to control the casting behavior in real time, so as to ensure the continuity and reliability of the casting process.

[0081] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0082] This specification uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A semi-continuous aluminum tube casting device with intelligent core removal, characterized in that, The system includes a frame, a traction system, a crystallizer vibration system, a core mold vibration system, a chute unit, a load-bearing plate, and a load-bearing base. The load-bearing plate is located on top of the frame. The crystallizer vibration system and the core mold vibration system are mounted on the load-bearing plate, with the core mold vibration system positioned above the crystallizer vibration system. The chute unit is located on the load-bearing plate and between the crystallizer vibration system and the core mold vibration system. The traction system is located below the load-bearing plate. The load-bearing base is located at the bottom of the frame. The traction system is used to pull aluminum tube blanks; the chute unit is used to preheat and guide the molten metal; the load-bearing plate is provided with material through holes; The crystallizer vibration system includes a crystallizer, a positioning and guiding unit, and a crystallization laser displacement sensor; the crystallizer is mounted on the positioning and guiding unit; the crystallization laser displacement sensor is located on the upper side of the crystallizer; the crystallization laser displacement sensor is used to detect the vibration amplitude of the crystallizer. The core mold vibration system includes a core mold vibration motor, a reducer, a core mold vibration bushing, a hinged sleeve unit, a hinged seat, a core mold laser displacement sensor, a core mold vibration tension / compression sensor, a vibration slider, a flange linear bearing, a mandrel, a heat insulation ring, and a core mold. The output shaft of the core mold vibration motor is connected to one end of the reducer, and the other end of the reducer is connected to the core mold vibration bushing. The hinged sleeve unit is located in the middle of the core mold vibration bushing. The hinged sleeve unit is connected to the hinged seat, and the core mold laser displacement sensor, the core mold vibration tension / compression sensor, the vibration slider, the flange linear bearing, the mandrel, the heat insulation ring, and the core mold are sequentially arranged below the hinged seat. The traction system includes a lower crossbeam, module positioning blocks, columns, a lead screw module, proximity sensors, a motor support, a traction motor, a spindle tray, connecting bolts, traction tension / compression sensors, and a spindle tray bracket. Both ends of the lower crossbeam are connected to the lower part of the frame. A lead screw module is mounted on the lower crossbeam, and the lead screw module is connected to one end of the spindle tray bracket. The spindle tray is mounted on the other end of the spindle tray bracket. A column is positioned above each end of the lower crossbeam, and a proximity sensor is mounted on the column closest to the lead screw module. A motor support is positioned above the load-bearing plate, and the traction motor is mounted on the motor support. The output shaft of the traction motor is connected to the lead screw module. A module positioning block is positioned at the top and bottom of the lead screw module. The traction tension / compression sensor is positioned between the spindle tray and the spindle tray bracket. The spindle tray and the spindle tray bracket are connected by the connecting bolts.

2. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 1, characterized in that, The crystallizer vibration system also includes a dual-shaft output reducer, a crystallization vibration motor, a reversing reducer, a crystallization vibration bushing, a shaft, a vibration platform, an eccentric wheel unit, and support bolts; The crystallizing vibration motor is provided on one side of the load-bearing plate. The output shaft of the crystallizing vibration motor is connected to the input end of the dual-shaft output reducer. The output end of the dual-shaft output reducer is connected to one end of the reversing reducer, and the other end of the reversing reducer is connected to the eccentric wheel unit for transmission. The two eccentric wheel units are located on both sides of the material through hole; Two positioning and guiding units are provided around the material through hole; Multiple support bolts are provided around the material through hole; The other end of the reversing reducer is sequentially provided with a crystallizing vibration sleeve, a shaft, and a crystallizing vibration sleeve between it and the eccentric wheel unit.

3. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 2, characterized in that, The positioning guide unit includes a positioning support, a positioning sleeve, and a copper sleeve; the positioning support is threadedly connected to the load-bearing plate, the positioning sleeve is threadedly connected to the bottom of the vibration platform and coaxial with the positioning support, the copper sleeve is built into the positioning sleeve and mates with the positioning support, the copper sleeve and the positioning sleeve have an interference fit, and the copper sleeve and the positioning support have a clearance fit. The eccentric wheel unit includes a vibrating sleeve, a vibrating sleeve end cap, bearing I, an eccentric shaft I, two bearings II, two bearing supports, and two bearing end caps. Bearing I is housed within the cavity formed by the vibrating sleeve and the vibrating sleeve end cap. The eccentric shaft I is fitted with the inner hole of bearing I. The vibrating sleeve is located between the two bearing supports. Bearing II is housed within the sealed space formed by the bearing supports and the bearing end caps. Bearing I and the vibrating sleeve have an interference fit. Bearing II and the bearing supports have an interference fit. The eccentric shaft I has a clearance fit with both bearing I and bearing II. The bearing supports are threaded onto the load-bearing plate. The crystallizer includes an outer mold and an inner mold. Cooling water inlet and outlet are provided on the outer mold. Small water outlet holes are evenly arranged on the bottom chamfer of the inner mold. An O-ring is provided at the top mating point between the outer mold and the inner mold. A groove is provided on the top of the crystallizer, and an annular heat-insulating material is placed in the groove as a heat-generating top. The dual-shaft output reducer is connected to the reversing reducer and the eccentric wheel unit through a bushing. The eccentricity of the eccentric shaft I in the eccentric wheel unit is 2-4 mm.

4. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 1, characterized in that, The core mold vibration system also includes a support beam, a support crossbeam, a motor bracket, an eccentric shaft, a sliding bearing seat, and a sliding bearing gasket. A supporting vertical beam is provided on each side of the load-bearing plate, and a supporting horizontal beam is provided between the tops of the two supporting vertical beams; A motor bracket is provided on the supporting crossbeam, and the core mold vibration motor is provided on the motor bracket; a sliding bearing seat is provided at each end of the core mold vibration bushing. A sliding bearing washer is provided between the sliding bearing seat and the top of the motor bracket.

5. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 4, characterized in that, In the mandrel vibration system, the eccentric shaft and the reducer are connected by the mandrel vibration bushing. The eccentric shaft and the inner hole of the sliding bearing seat are in clearance fit. The hinge sleeve unit and the hinge seat are connected by a pin. The tension / compression sensor is threaded between the hinge seat and the vibration slider. The vibration slider and the flange linear bearing are in clearance fit. The flange linear bearing is threaded onto the support beam. The mandrel and the mandrel are threaded together, and a high-temperature resistant O-ring is provided at the bottom of the threaded fit. Cooling water for cooling molten metal flows through the mandrel and the mandrel. The mandrel has a mandrel inlet and outlet water port.

6. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 4, characterized in that, Both the crystallizer and the core mold are made of aluminum alloy. The inner diameter of the crystallizer is 80-140mm, and the outer diameter of the core mold is 40-80mm. The water holes evenly arranged on the bottom chamfer of the inner mold of the crystallizer have an angle of 45°-60° with the horizontal direction. The taper of the core mold is 1°-2°, and the crystallizer and the core mold are coaxial.

7. The semi-continuous aluminum tube casting device with intelligent core removal according to claim 1, characterized in that, The chute unit includes insulation material inside the chute shell, a cast copper heating plate located below the chute shell to preheat the chute, a chute support located on and connected to the frame, and insulation material located between the cast copper heating plate and the chute support to provide thermal insulation.

8. A casting method for a semi-continuous aluminum tube casting apparatus with intelligent core removal, characterized in that, The process is carried out using the semi-continuous aluminum tube casting apparatus with intelligent core removal as described in any one of claims 1-7, and includes the following steps: 1) Lift the traction plate in the traction system to the bottom of the core mold in the crystallizer vibration system and make contact with the core mold. Then, pass cold water into the crystallizer and the core mold until the cooling water flows out from the crystallizer nozzle and the core rod nozzle. At the same time, preheat the chute unit to 400-600℃. 2) Molten aluminum is injected into the chute unit and enters the crystallizer through the chute unit. The temperature of the molten aluminum is 700-720℃. When the liquid level of the molten metal in the crystallizer reaches the specified height, the traction system is started to start casting. At the same time, the crystallizer vibration system is turned on. If core seizure is about to occur during the aluminum tube casting process, the force signals fed back by the traction tension and compression sensor and the core mold vibration tension and compression sensor are sent to the CPU module of the PLC to control the core mold vibration motor to rotate through the servo driver, thereby driving the core rod to vibrate to avoid core seizure. 3) When the ingot guide plate in the traction system moves downward to the designated position, stop injecting aluminum liquid into the chute unit until the aluminum alloy ingot is completely pulled out of the crystallizer, turn off the crystallizer vibration system, the core mold vibration system and the cooling water, and stop casting. The pipe demolding method includes the following steps: When the actual axial force between the tube and the mandrel is less than the critical value for mandrel clamping, the semi-continuous vibration casting equipment for aluminum tubes can operate normally; when the actual axial force between the tube and the mandrel is greater than the critical value for mandrel clamping, mandrel clamping occurs. The PLC will process the signal transmitted by the traction and tension sensors and send out the first motion feedback and the second motion feedback. The first motion feedback causes the mandrel vibration system to start working, and the mandrel drives the mandrel to vibrate up and down. The second motion feedback causes the ingot guide plate to stop descending. The initial position of the mandrel is uncertain, and the mandrel starts to move in two directions: upward and downward.

9. The casting method of the semi-continuous aluminum tube casting device with intelligent core removal according to claim 8, characterized in that, 1) The mandrel moves upward; When the mandrel moves upward, the actual parameters of the traction and compression sensor are less than the theoretical parameters, and the position where the pipe falls off is divided into two types: above the initial position and below the initial position; ① When the pipe falls off above the initial position, the pipe has an initial velocity and acceleration. The actual parameter of the traction and tension sensor is greater than the theoretical parameter and the actual parameter of the traction and tension sensor is equal to the theoretical parameter for a short time. The PLC will receive the signal transmitted by the traction and tension sensor and send the first motion feedback and the second motion feedback. The first motion feedback causes the mandrel vibration system to stop working, and the second motion feedback causes the dart plate to start descending. When the pipe falls off above the initial position, the following command is executed when the pipe falls off at the initial position. ② When the pipe falls off below the initial position, and the actual parameter of the traction and tension sensor is greater than the theoretical parameter and does not change within a short period of time, the PLC receives the signal transmitted by the traction and tension sensor and sends out the second motion feedback. The second motion feedback causes the bobbin to descend by a height h, and the maximum value of h cannot exceed 1 / 5-1 / 3 of the liquid level. When the actual parameter of the traction and tension sensor is equal to the theoretical parameter and does not change within a certain period of time, the PLC receives the signal transmitted by the traction and tension sensor and sends out the first motion feedback and the second motion feedback. The first motion feedback causes the core mold vibration system to stop working, and the second motion feedback causes the bobbin to start descending. When the pipe has not fallen off below the initial position, the command to make the pipe fall off above the initial position is executed. 2) The mandrel moves downwards. When the mandrel moves downward, the position where the tube falls off is either below the initial position or above the initial position, and the motion feedback is the same as when the mandrel moves upward.

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