Casting shrinkage-proof device for hot working casting

Abstract

The invention discloses a casting shrinkage-proof device for hot-working casting, and belongs to the technical field of hot-working casting, by arranging a heating mechanism and a knocking mechanism, through vibration and disturbance generated by knocking, the static state of 21800 austenitic stainless steel metal liquid in a casting mold can be broken, and the shrinkage-proof performance of the casting is improved. According to the technical scheme, small bubbles originally attached to the interior or the wall face of liquid are disturbed and start to float upwards, meanwhile, vibration can improve the liquidity of the metal liquid, crank knocking is started in the process that the metal liquid is injected into a casting mold, knocking is still continuously kept after the metal liquid is injected, knocking power is from pushing of steam, and therefore the effect of improving the fluidity of the metal liquid is achieved. No other external force is needed in the process, and the knocking frequency is gradually reduced until the knocking frequency is completely stopped along with cooling of metal, weakening of power generated by steam and reduction of the casting mold temperature, so that the purpose of preventing the stability of metal liquid during condensation from being damaged by excessive knocking is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hot processing casting, and particularly relates to a device for preventing shrinkage cavities in castings for hot processing casting. Background Art

[0002] In the process of melting metal into molten metal and pouring it into the sand mold cavity of a mold, the molten metal will carry air into the casting cavity and form bubbles. Due to the relatively large density of the molten metal, the bubbles in the molten metal are difficult to float and discharge, resulting in shrinkage on the surface of the casting during the condensation process and generating holes. This phenomenon is called shrinkage cavity. The shape of the shrinkage cavity is irregular, the hole wall is rough, and it is generally located at the hot spot of the casting. After the ingot is rolled into a profile, wrinkles or holes will be formed in the central part of the cross-section, and serious porosity, segregation and oxide aggregation often appear nearby, seriously affecting the quality of the casting; The existing methods for removing bubbles include drying the mold to avoid excessive moisture content in the air in the mold and generating water vapor during pouring, and using a filter screen to disperse the large bubbles in the molten metal into small bubbles to reduce the difficulty of their floating, etc.; During the casting process of an angle valve made of 21800 austenitic stainless steel, since the valve body of the angle valve usually has three ports, an inlet port, a water volume control port and an outlet port, these three ports are distributed at 90 degrees on the valve body, forming a unique corner shape layout of the angle valve; Therefore, the bubbles generated at the vertical part of the angle valve can be filled and discharged by using the mass of the molten metal. However, for the bubbles generated at the horizontal part, due to the poor filling effect, the floating path of the bubbles is far from the exhaust hole and is easily blocked by the inner wall, and the fluidity of the molten metal in the horizontal direction is poor, and the bubbles are easily squeezed by the surrounding liquid and difficult to move. Therefore, it is difficult to use the above methods to remove bubbles. Summary of the Invention

[0003] The purpose of the present invention is to propose a device for preventing shrinkage cavities in castings for hot processing casting to solve the problem that during the casting process of an angle valve, for the bubbles generated at the horizontal part, due to the poor filling effect, the floating path of the bubbles is far from the exhaust hole and is easily blocked by the inner wall, and the fluidity of the molten metal in the horizontal direction is poor, and the bubbles are easily squeezed by the surrounding liquid and difficult to move.

[0004] To achieve the above purpose, the present invention adopts the following technical solution: a device for preventing shrinkage cavities in castings for hot processing casting: It includes an angle valve casting, the angle valve casting includes two L-shaped molds, a heating mechanism is sleeved on the horizontal part of the mold, the heating mechanism includes a shell for storing liquid and a metal heat exchanger arranged in the shell and in contact with the mold for heat exchange, and the metal heat exchanger heats the liquid to generate steam through the heat of the mold; A knocking mechanism is installed at the top of the mold. The knocking mechanism includes a sealed cavity communicated with the shell and a piston arranged in the sealed cavity. The steam generated in the shell pushes the piston to reciprocate in the sealed cavity. A push rod penetrating the sealed cavity is installed on the piston, and a crank is hinged at the end of the push rod. The crank knocks the side wall of the mold as the push rod reciprocates.

[0005] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: The shell includes a split sub-shell and a mother shell. Installation grooves are provided on both the sub-shell and the mother shell. After the sub-shell and the mother shell are combined, the sealed cavity is fixed through the installation grooves.

[0006] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: The knocking mechanism further includes a connecting piece installed on the mold. The connecting piece includes two sliding grooves provided on the mold. An articulated shaft is slidably embedded in the sliding grooves. The crank is hinged to the articulated shaft. Two communicating pipes are installed at the bottom of the sealed cavity. One end of the communicating pipe is inserted into the sealed cavity, and the other end is connected with a gas exchange mechanism for air change.

[0007] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: A knocking piece made of flexible material is installed at the end of the crank.

[0008] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: The gas exchange mechanism includes an air inlet cavity installed below the sealed cavity and a pressure reduction cavity opened on the air inlet cavity. Two air holes are opened at the bottom of the air inlet cavity, and the top is connected with two communicating pipes. The communicating pipes include a first air inlet and outlet pipe and a second air inlet and outlet pipe respectively installed at the two side ends of the sealed cavity and the air inlet cavity. A sealing piece for blocking the air holes is slidably arranged inside the air inlet cavity. The steam enters the air inlet cavity through the unblocked air holes, and enters the sealed cavity through any one of the first air inlet and outlet pipe or the second air inlet and outlet pipe to push the piston to move. At the same time, the waste gas on the other side of the piston enters the sealing piece through any one of the first air inlet and outlet pipe or the second air inlet and outlet pipe under the push of the piston, and reaches the pressure reduction cavity through the sealing piece and is discharged.

[0009] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: The gas exchange mechanism further includes a connecting rod movably installed on the air inlet cavity and connected with the sealing piece and an exhaust pipe installed on the pressure reduction cavity. Both the connecting rod and the exhaust pipe penetrate and extend outside the shell.

[0010] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: A first mounting bracket is installed on the housing. A first hinge member is rotatably installed on the first mounting bracket. A contact plate and a telescopic extension member are installed on the first hinge member. And a second hinge member connected to the connecting rod is installed at the end of the extension member. A telescopic movable contact block is installed on the push rod. When the push rod moves, the movable contact block abuts against the contact plate and pushes the second hinge member to deflect about the first hinge member to pull the connecting rod to move, and the connecting rod drives the closing member to move.

[0011] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: A water replenishing mechanism is installed on the mother housing. The water replenishing mechanism includes a liquid level detection cavity arranged on the mother housing and communicated with the mother housing, and a second mounting bracket installed on the mother housing to reinforce the liquid level detection cavity. An inlet valve is installed at the bottom of the liquid level detection cavity and an exhaust valve is installed at the top. The exhaust valve and the inlet valve are communicated through a connecting pipe. When the inlet valve is opened, the liquid reaches the exhaust valve through the connecting pipe and is injected into the liquid level detection cavity to supplement the liquid lost due to heating in the housing.

[0012] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: The exhaust valve includes a valve housing installed at the top of the liquid level detection cavity and an exhaust hole opened on the valve housing. A spherical valve is rotatably arranged in the valve housing. An L-shaped hole is opened in the spherical valve. An adjusting knob meshing with the valve housing is installed at the top of the spherical valve.

[0013] As a further description of a shrinkage cavity prevention device for castings in hot processing casting of the above technology: A liquid level detection mechanism is arranged in the liquid level detection cavity. The liquid level detection mechanism includes a lifting cavity installed in the liquid level detection cavity and a closing hole opened at the top of the lifting cavity. A plurality of water inlet holes are opened on the surface of the lifting cavity and a floating ball is arranged inside. A sealing member capable of sealing the closing hole is arranged at the top of the floating ball. A contact point electrically connected to the inlet valve is installed at the bottom of the lifting cavity. When the contact point contacts the floating ball, the inlet valve is controlled to open.

[0014] In summary, due to adopting the above technology of a shrinkage cavity prevention device for castings in hot processing casting, the beneficial effects of the present invention are: 1. By means of the provided heating mechanism and knocking mechanism, during the process of injecting molten metal into the mold, the high temperature generated heats the water in the shell through the metal heat exchanger and generates steam. The steam enters the sealed cavity and pushes the piston to move, causing the piston to push the push rod. The crank connected to the end of the push rod deflects and knocks the mold under the restriction of the connecting piece. Through the vibration and disturbance generated by the knocking, it helps to break the static state of the molten metal in the mold, enabling the small bubbles originally attached inside or on the wall of the liquid to be disturbed and start to float upward. At the same time, the vibration can also increase the fluidity of the molten metal. The knocking of the crank starts during the process of injecting the molten metal into the mold and continues to knock even after the injection of the molten metal is completed. The power of the knocking comes from the push of the steam, and no other external force is required during the process. As the metal cools, the power generated by the steam weakens, and as the temperature of the mold decreases, the knocking frequency gradually decreases until it completely stops, so as to achieve the purpose of avoiding excessive knocking from damaging the stability of the molten metal during condensation; 2. Through the provided gas exchange mechanism, the new steam entering the sealed cavity pushes the piston, compressing the space in the sealed cavity, thereby pressing the waste gas on the other side of the piston out of the sealed cavity through the first air inlet and outlet pipe. The waste gas is collected in the sealing piece and reaches the pressure reduction cavity, and then is discharged outside the mold through the exhaust pipe connected to the pressure reduction cavity. By circulating the above operations, the circulation of the steam in the sealed cavity and the reciprocating movement of the push rod can be realized, thereby realizing the action of the crank knocking the mold. Description of the Drawings

[0015] Figure 1 Shows a three-dimensional structural schematic diagram of a shrinkage cavity prevention device for castings in hot processing casting; Figure 2 Shows Figure 1 The enlarged structural schematic diagram at position A in; Figure 3 Shows a front sectional structural schematic diagram of a shrinkage cavity prevention device for castings in hot processing casting; Figure 4 Shows a three-dimensional structural schematic diagram of the heating mechanism, knocking mechanism and water replenishing mechanism; Figure 5 Shows Figure 4 The enlarged structural schematic diagram at position B in; Figure 6 Shows a side sectional structural schematic diagram of the heating mechanism and knocking mechanism; Figure 7 Shows the disassembled state schematic diagram of the sub-shell and the mother shell; Figure 8 Shows a three-dimensional sectional structural schematic diagram of the knocking mechanism and gas exchange mechanism; Figure 9 Shows the first steam flow direction schematic diagram inside the knocking mechanism and gas exchange mechanism; Figure 10 Shows a schematic diagram of the second steam flow direction in the knocking mechanism and the gas exchange mechanism; Figure 11 Shows a three-dimensional structural schematic diagram of the closure and the slide rail; Figure 12 Shows a three-dimensional structural schematic diagram of the water replenishing mechanism; Figure 13 Shows a front sectional structural schematic diagram of the housing and the water replenishing mechanism and a schematic diagram of the steam flow direction; Figure 14 Shows a front sectional structural schematic diagram of the housing and the water replenishing mechanism and a schematic diagram of the supplementary water flow direction; Figure 15 Shows a three-dimensional structural schematic diagram of the ball valve and the adjusting knob.

[0016] Legend Explanation: 10. Angle valve casting; 11. Runner; 12. Mold; 13. Gate; 14. Exhaust passage; 20. Heating mechanism; 21. Housing; 211. Sub-housing; 212. Mother housing; 22. Metal heat exchanger; 23. Installation groove; 30. Knocking mechanism; 31. Sealing cavity; 32. Piston; 33. Connecting pipe; 331. First intake and exhaust pipe; 332. Second intake and exhaust pipe; 34. Push rod; 35. Connecting piece; 351. Hinge shaft; 352. Slide groove; 36. Crank; 361. Knocking piece; 40. Gas exchange mechanism; 41. Intake cavity; 42. Closure; 421. Slide rail; 43. Pressure reduction cavity; 44. Connecting rod; 45. Exhaust pipe; 46. First mounting bracket; 47. First hinge piece; 48. Extension piece; 49. Second hinge piece; 410. Contact plate; 411. Movable contact block; 50. Water replenishing mechanism; 51. Second mounting bracket; 52. Liquid level detection cavity; 53. Water inlet valve; 54. Connecting pipe; 55. Exhaust valve; 551. Valve housing; 552. Ball valve; 553. Adjusting knob; 554. Exhaust hole; 60. Liquid level detection mechanism; 61. Lifting cavity; 62. Contact point; 63. Floating ball; 64. Sealing piece; 65. Sealing hole. Detailed Implementation Manner

[0017] Next, the technical solution of a shrinkage cavity prevention device for castings in hot processing casting in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0018] In order to solve the problem that during the casting process of the angle valve, the bubbles generated in the horizontal part are affected by poor compaction effect, the floating path of the bubbles is far from the exhaust hole and is easily blocked by the inner wall, and the fluidity of the molten metal in the horizontal direction is poor, and the bubbles are easily squeezed by the surrounding liquid and difficult to move, the present invention proposes a device for preventing shrinkage holes in castings for hot processing casting, as Figure 1 - Figure 15 shown: It includes an angle valve casting 10, and the production material of the angle valve casting 10 uses 21800 austenitic stainless steel, as Figure 1 shown, the angle valve casting 10 includes a runner 11 and two L-shaped molds 12 installed on both sides of the runner 11. A gate 13 and an exhaust passage 14 are installed on the runner 11. Molten metal is injected into the runner 11 through the gate 13 and is split into the two molds 12. The bubbles generated during the filling of the molds 12 are discharged through the exhaust passage 14; In order to reduce the generation of bubbles in the horizontal part of the mold 12, as Figure 3 、 Figure 4 、 Figure 6 and Figure 7 shown, a heating mechanism 20 is sleeved on the horizontal part of the mold 12. The heating mechanism 20 includes a housing 21 for storing liquid and a metal heat exchanger 22 disposed in the housing 21 and in contact with the mold 12 for heat exchange. The metal heat exchanger 22 heats the liquid through the heat of the mold 12 to generate steam; The housing 21 includes a split sub-housing 211 and a mother housing 212. Before casting, the housing 21 is fitted and installed at the bottom of the horizontal part of the mold 12, and then the sub-housing 211 and the mother housing 212 are sleeved on the mold 12 and the housing 21 and assembled into the housing 21. After installation, liquid is injected into the housing 21. Preferably, the liquid is water. After checking for leaks, the installation of the heating mechanism 20 is completed; At the same time, mounting grooves 23 are provided on both the sub-housing 211 and the mother housing 212. After the sub-housing 211 and the mother housing 212 are combined, a knocking mechanism 30 is fixed through the mounting grooves 23, as Figure 6 shown, the knocking mechanism 30 includes a sealing cavity 31 communicated with the housing 21 and a piston 32 disposed in the sealing cavity 31. The steam generated in the housing 21 pushes the piston 32 to reciprocate in the sealing cavity 31. A push rod 34 passing through the sealing cavity 31 is installed on the piston 32. The end of the push rod 34 is hinged to a crank 36, and the crank 36 knocks the side wall of the mold 12 as the push rod 34 reciprocates.

[0019] The knocking mechanism 30 further includes a connecting member 35 installed on the mold 12. The connecting member 35 includes two sliding grooves 352 provided on the mold 12, and a hinge shaft 351 is slidably embedded in the sliding grooves 352. The crank 36 is hinged to the hinge shaft 351; During the process of pouring molten metal into the mold 12, the high temperature generated heats the water in the housing 21 through the metal heat exchanger 22 and generates steam. The steam enters the sealed chamber 31 and pushes the piston 32 to move, causing the piston 32 to push the push rod 34. The crank 36 connected to the end of the push rod 34 deflects and strikes the mold 12 under the restriction of the connecting member 35. Through the vibration and disturbance generated by the striking, it helps to break the static state of the molten metal in the mold 12, causing the small bubbles originally attached inside or on the wall of the liquid to be disturbed and start to float. At the same time, the vibration can also increase the fluidity of the molten metal. The striking of the crank 36 starts during the process of pouring the molten metal into the mold 12 and continues to strike even after the pouring of the molten metal is completed. The power of the striking comes from the push of the steam, and no other external force is required to intervene during the process. As the metal cools, the power generated by the steam weakens. As the temperature of the mold 12 decreases, the striking frequency gradually decreases until it completely stops, so as to achieve the purpose of avoiding excessive striking from damaging the stability of the molten metal during condensation; It should be noted that the deflection of the crank 36 is arc-shaped while the push rod 34 moves horizontally. Therefore, when the crank 36 and the push rod 34 are vertically distributed, the push rod 34 will push the hinge shaft 351 to slide a certain distance under the restriction of the chute 352 through the crank 36, and when they are not vertically distributed, it will pull the hinge shaft 351 to slide back in the reverse direction; In order to avoid damage to the surface of the mold 12 caused by the striking of the crank 36 on the mold 12, a striking member 361 made of a flexible material is installed at the end of the crank 36. The flexible material is one of polyvinyl alcohol PVA, polyester PET, and polyimide PI; Furthermore, in order to discharge the exhaust gas that has lost kinetic energy due to pushing the piston 32 from the sealed chamber 31 without affecting the normal movement of the piston 32, as Figures 8 - 10 shown, two communication pipes 33 are installed at the bottom of the sealed chamber 31. One end of the communication pipe 33 is inserted into the sealed chamber 31, and the other end is connected to a gas exchange mechanism 40 for air exchange; As Figure 8 shown, the gas exchange mechanism 40 includes an intake chamber 41 installed below the sealed chamber 31 and a pressure reduction chamber 43 opened on the intake chamber 41. Two air holes are opened at the bottom of the intake chamber 41, and the top is connected to the two communication pipes 33. The communication pipes 33 include a first inlet and outlet pipe 331 and a second inlet and outlet pipe 332 respectively installed at the two ends of the sealed chamber 31 and the intake chamber 41; Inside the air inlet chamber 41, a sealing member 42 for blocking the air holes is slidably arranged. Steam enters the air inlet chamber 41 through the unblocked air holes, and enters the sealing chamber 31 through any one of the first air inlet and outlet pipe 331 or the second air inlet and outlet pipe 332 to push the piston 32 to move. At the same time, the waste gas on the other side of the piston 32 enters the sealing member 42 under the push of the piston 32, passes through the sealing member 42 and reaches the pressure reduction chamber 43 for discharge; In order to improve the stability of the movement of the sealing member 42, as Figure 11 shown, slide rails 421 are arranged on both sides of the inner wall of the air inlet chamber 41, and both sides of the sealing member 42 are slidably embedded on the slide rails 421, so as to prevent the sealing member 42 from shifting during the sliding process; The air exchange mechanism 40 further includes a connecting rod 44 movably installed on the air inlet chamber 41 and connected to the sealing member 42, and an exhaust pipe 45 installed on the pressure reduction chamber 43. Both the connecting rod 44 and the exhaust pipe 45 penetrate and extend outside the housing 21; During specific operation, the water in the housing 21 is heated into steam and enters through the air hole at the bottom of the air inlet chamber 41 near the first air inlet and outlet pipe 331, and is injected into the piston 32 through the first air inlet and outlet pipe 331. Under the push of the steam, the piston 32 moves inside the sealing chamber 31 and pulls the push rod 34, so that the push rod 34 drives the crank 36 to strike the mold 12; At the same time, a first mounting bracket 46 is installed on the housing 21. A first hinge member 47 is rotatably installed on the first mounting bracket 46. A contact plate 410 and a telescopic extension member 48 are installed on the first hinge member 47, and a second hinge member 49 connected to the connecting rod 44 is installed at the end of the extension member 48; A retractable movable abutting block 411 is installed on the push rod 34. When the push rod 34 moves, the movable abutting block 411 abuts against the abutting plate 410, and pushes the second hinge member 49 to deflect with the first hinge member 47 as the axis to pull the connecting rod 44 to move. The connecting rod 44 drives the closing member 42 to move. During the movement of the push rod 34, the push rod 34 pushes the abutting plate 410 by pushing the movable abutting block 411. When the movable abutting block 411 pushes the abutting plate 410 to deflect to the maximum angle on the other side, it can contract under the push of the abutting plate 410 to achieve the purpose of disengaging from the abutting with the abutting plate 410, so that the abutting plate 410 drives the first hinge member 47 to deflect under the restriction of the first mounting bracket 46. The first hinge member 47 pulls the second hinge member 49 through the extension member 48. During the pulling process, the second hinge member 49 moves on the surface of the extension member 48 to make up for the distance change between the first hinge member 47 and the second hinge member 49, so that the second hinge member 49 pulls the connecting rod 44, and the connecting rod 44 drives the closing member 42 to slide inside the air inlet chamber 41 and block the air hole near the first air inlet and outlet pipe 331, and at the same time opens the air hole near the second air inlet and outlet pipe 332. Steam enters the air inlet chamber 41 through the air hole and is introduced into the sealing chamber 31 through the second air inlet and outlet pipe 332, pushing the piston 32 to move reversely inside the sealing chamber 31. The push rod 34 is driven by the piston 32 to drive the crank 36 to lift away from the mold 12; At the same time, the new steam entering the sealing chamber 31 pushes the piston 32, compressing the space inside the sealing chamber 31, so as to press the waste gas on the other side of the piston 32 out of the sealing chamber 31 through the first air inlet and outlet pipe 331. The waste gas is collected in the closing member 42 and reaches the pressure reducing chamber 43, and then is discharged outside the mold 12 through the exhaust pipe 45 connected to the pressure reducing chamber 43. By circulating the above operations, the circulation of steam inside the sealing chamber 31 and the reciprocating movement of the push rod 34 can be realized, so as to realize the action of the crank 36 knocking the mold 12.

[0020] To avoid damage to the housing 21 at high temperature due to too little water inside the housing 21, as Figure 12 shown, a water replenishing mechanism 50 is installed on the mother housing 212. The water replenishing mechanism 50 includes a liquid level detection chamber 52 provided on the mother housing 212 and communicated with the mother housing 212, and a second mounting bracket 51 installed on the mother housing 212 to reinforce the liquid level detection chamber 52; An inlet valve 53 is installed at the bottom of the liquid level detection chamber 52 and an exhaust valve 55 is installed at the top. The exhaust valve 55 is communicated with the inlet valve 53 through a connecting pipe 54. When the inlet valve 53 is opened, the liquid reaches the exhaust valve 55 through the connecting pipe 54 and is injected into the liquid level detection chamber 52 to supplement the liquid lost due to heating inside the housing 21.

[0021] Further, as Figures 13 - 15As shown in the figure, the exhaust valve 55 includes a valve housing 551 installed at the top of the liquid level detection chamber 52 and an exhaust hole 554 opened on the valve housing 551. A spherical valve 552 is rotatably arranged in the valve housing 551. An L-shaped hole is opened in the spherical valve 552. An adjustment knob 553 engaged with the valve housing 551 is installed at the top of the spherical valve 552; When it is necessary to release the excess steam in the mold 12, by rotating the adjustment knob 553, the spherical valve 552 rotates in the valve housing 551. The two ends of the L-shaped hole of the spherical valve 552 are respectively aligned with the water inlet valve 53 and the exhaust hole 554. The steam in the housing 21 enters through the valve housing 551, passes through the spherical valve 552, reaches the exhaust hole 554 and is discharged; When it is necessary to replenish water, by rotating the adjustment knob 553, the two ends of the L-shaped hole of the spherical valve 552 are respectively aligned with the connecting pipe 54 and the liquid level detection chamber 52. When the excess steam in the housing 21 has been discharged, the water inlet valve 53 is opened. The water flows through the connecting pipe 54 into the valve housing 551, flows through the spherical valve 552 and enters the housing 21, and the water replenishment operation is completed; When normal use is required, just align the horizontal end of the L-shaped hole with the inner wall of the valve housing 551 for blocking, and neither steam nor water can pass through the spherical valve 552.

[0022] In order to achieve automatic water replenishment, as Figure 12 and Figure 13 shown, a liquid level detection mechanism 60 is arranged in the liquid level detection chamber 52. The liquid level detection mechanism 60 includes a lifting chamber 61 installed in the liquid level detection chamber 52 and a closed hole 65 opened at the top of the lifting chamber 61. A plurality of water inlet holes are opened on the surface of the lifting chamber 61 and a floating ball 63 is arranged inside. A plugging member 64 capable of plugging the closed hole 65 is arranged at the top of the floating ball 63, A contact 62 electrically connected to the water inlet valve 53 is installed at the bottom of the lifting chamber 61. When the water level in the mold 12 is too low, the floating ball 63 drives the plugging member 64 to be pulled out of the closed hole 65 and gradually drops with the water level in the mold 12 until it contacts the contact 62. After the contact 62 contacts the floating ball 63, it controls the water inlet valve 53 to open, so that the water can pass through the water inlet valve 53, through the connecting pipe 54, the exhaust valve 55 and the closed hole 65 and be injected into the housing 21. As the water level in the housing 21 rises, the floating ball 63 floats up and drives the plugging member 64 to insert into the closed hole 65 to prevent the water from continuing to be injected. As the water flow stops, the water inlet valve 53 automatically closes and the automatic water replenishment is completed.

[0023] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical idea of the present invention, makes equivalent replacements or changes, and should be covered by the protection scope of the present invention.

Claims

1. A casting shrinkage prevention device for hot working casting, comprising an angle valve casting (10), the angle valve casting (10) comprising two L-shaped casting molds (12), characterized in that: A heating mechanism (20) is sleeved on the horizontal portion of the casting mold (12), the heating mechanism (20) comprising a shell (21) for storing liquid and a metal heat exchanger (22) disposed in the shell (21) and in contact with the casting mold (12) for heat exchange, the metal heat exchanger (22) heating the liquid to generate steam by using the heat of the casting mold (12); A knocking mechanism (30) is installed on the top of the casting mold (12). The knocking mechanism (30) comprises a sealed cavity (31) connected to the shell (21) and a piston (32) arranged in the sealed cavity (31). Steam generated in the shell (21) drives the piston (32) to move back and forth in the sealed cavity (31). A push rod (34) penetrating the sealed cavity (31) is installed on the piston (32). A crank (36) is hingedly connected to the end of the push rod (34). The crank (36) knocks the side wall of the casting mold (12) as the push rod (34) moves back and forth.

2. The device for preventing shrinkage holes in castings for hot working casting according to claim 1, characterized in that: The housing (21) comprises a split sub-housing (211) and a main housing (212), both the sub-housing (211) and the main housing (212) being provided with a mounting groove (23), and the sub-housing (211) and the main housing (212) are combined to fix the sealed cavity (31) via the mounting groove (23).

3. The device for preventing shrinkage holes in castings for hot working casting according to claim 1, characterized in that: The striking mechanism (30) further comprises a connecting member (35) mounted on the casting mold (12), the connecting member (35) comprising two slide grooves (352) arranged on the casting mold (12), a hinge shaft (351) being slidably embedded in the slide grooves (352), and the crank (36) being hinge-connected to the hinge shaft (351); Two connecting pipes (33) are installed at the bottom of the sealed cavity (31); one end of the connecting pipe (33) is inserted into the sealed cavity (31), and the other end is connected to a gas exchange mechanism (40) for ventilation.

4. A device for preventing shrinkage holes in castings for hot working casting according to claim 1 or 3, characterized in that: A striking piece (361) made of a flexible material is mounted on the end of the crank (36).

5. The device for preventing shrinkage holes in castings for hot working casting according to claim 3, characterized in that: The air exchange mechanism (40) comprises an air intake chamber (41) installed below the sealed chamber (31) and a pressure reduction chamber (43) opened on the air intake chamber (41); the air intake chamber (41) has two air holes opened at the bottom and is connected to two connecting pipes (33) at the top; the connecting pipes (33) comprise a first air intake and outlet pipe (331) and a second air intake and outlet pipe (332) respectively installed at the ends of both sides of the sealed chamber (31) and the air intake chamber (41); A sealing member (42) for sealing air holes is slidably disposed inside the air inlet chamber (41); steam enters the air inlet chamber (41) through the unsealed air holes and enters the sealing chamber (31) through any one of the first air inlet and outlet pipes (331) or the second air inlet and outlet pipes (332) to push the piston (32) to move; at the same time, the exhaust gas on the other side of the piston (32) enters the sealing member (42) through any one of the first air inlet and outlet pipes (331) or the second air inlet and outlet pipes (332) under the push of the piston (32), and passes through the sealing member (42) to reach the pressure reduction chamber (43) for discharge.

6. The device for preventing shrinkage holes in castings for hot working casting according to claim 5, characterized in that: The gas exchange mechanism (40) further comprises a connecting rod (44) movably mounted on the air inlet chamber (41) and connected to the sealing member (42), and an exhaust pipe (45) mounted on the pressure reducing chamber (43); the connecting rod (44) and the exhaust pipe (45) both penetrate and extend outside the housing (21).

7. The device for preventing shrinkage holes in castings for hot working casting according to claim 6, characterized in that: The housing (21) is mounted with a first mounting frame (46), a first hinged member (47) is rotatably mounted on the first mounting frame (46), an abutment plate (410) and a retractable extension member (48) are mounted on the first hinged member (47), and a second hinged member (49) connected to the connecting rod (44) is mounted at the end of the extension member (48); A retractable movable abutment block (411) is mounted on the push rod (34). When the push rod (34) moves, the movable abutment block (411) abuts against the abutment plate (410), and pushes the second hinge (49) to deflect about the first hinge (47) to pull the connecting rod (44) to move, and the connecting rod (44) drives the closing member (42) to move.

8. The device for preventing shrinkage holes in castings for hot working casting according to claim 2, characterized in that: The mother shell (212) is provided with a water replenishment mechanism (50), the water replenishment mechanism (50) comprising a liquid level detection cavity (52) disposed on the mother shell (212) and in communication with the mother shell (212), and a second mounting frame (51) mounted on the mother shell (212) and reinforcing the liquid level detection cavity (52); The liquid level detection chamber (52) is provided with a water inlet valve (53) at the bottom and an exhaust valve (55) at the top. The exhaust valve (55) is connected to the water inlet valve (53) via a connecting pipe (54). When the water inlet valve (53) is opened, liquid flows through the connecting pipe (54) to the exhaust valve (55) and is injected into the liquid level detection chamber (52) to replenish the liquid lost in the housing (21) due to heating.

9. The device for preventing shrinkage holes in castings for hot working casting according to claim 8, characterized in that: The exhaust valve (55) comprises a valve housing (551) mounted on the top of the liquid level detection chamber (52) and an exhaust hole (554) provided on the valve housing (551); a spherical valve (552) is rotatably arranged in the valve housing (551); an L-shaped hole is provided in the spherical valve (552); and an adjusting knob (553) engaged with the valve housing (551) is installed on the top of the spherical valve (552).

10. The device for preventing shrinkage holes in castings for hot working casting according to claim 8, characterized in that: A liquid level detection mechanism (60) is arranged in the liquid level detection chamber (52), the liquid level detection mechanism (60) comprising a lifting chamber (61) installed in the liquid level detection chamber (52) and a closed hole (65) provided at the top of the lifting chamber (61), a plurality of water inlet holes being provided on the surface of the lifting chamber (61) and a floating ball (63) being arranged inside the lifting chamber (61), a sealing member (64) capable of sealing the closed hole (65) being provided at the top of the floating ball (63), A contact (62) electrically connected to the water inlet valve (53) is installed at the bottom of the lifting chamber (61); when the contact (62) contacts the floating ball (63), the water inlet valve (53) is controlled to open.

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