Technological equipment for eliminating casting shrinkage porosity

Abstract

The utility model relates to the technical field of swage sand-coated casting, in particular to process equipment for eliminating casting shrinkage porosity, which comprises a chilling block pipe, the inner end of the chilling block pipe is inserted into a chilling block through hole in a matching manner and is blocked, the inner end face of the chilling block pipe is matched with the inner surface of the corresponding position of a casting swage, and the chilling block pipe is inserted into the chilling block through hole. An inner pipe cavity is formed in the chilling block pipe, and an end plugging piece is screwed to an outer end opening of the inner pipe cavity in a threaded mode. The process equipment designed in the utility model is mainly mounted in the chilling block through holes formed in the hot spot areas of the casting iron mold for use, when a plurality of hot spot areas exist on the casting iron mold, the chilling block through holes are formed in the hot spot areas in advance, and one process equipment is mounted in each chilling block through hole in a matched manner; and the cooling speed of the molten iron in the hot spot area at the corresponding position is effectively reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of iron mold sand covered casting, in particular to a new process equipment for increasing the cooling rate of hot spot parts in iron mold casting to reduce or eliminate shrinkage porosity defects of castings, especially a process equipment for eliminating shrinkage porosity of castings. Background Art

[0002] The iron mold sand covered casting process is a modern special casting method, which can coat or adhere a layer of molding sand suitable for the casting material on the inner cavity surface of the iron mold, and then form a mold after baking and hardening, so as to produce various ductile iron castings.

[0003] In the traditional iron mold casting process, the assembly used is generally an iron mold for casting, which is an indispensable part of the iron mold sand covered casting process. For example, in the patent document with the patent publication number CN206009732U, an iron mold for casting is disclosed, which belongs to one of the currently commonly used casting molds. Its main structure includes a mold body, on which a plurality of iron mold units for casting are arranged in parallel, a mold wall is arranged between adjacent iron mold units for casting, and there is a distance between the overall adjacent iron mold units for casting in the vertical direction.

[0004] The above-mentioned iron mold for casting is used to form the external contour and internal structure of the casting in the iron mold sand covered casting process, mainly playing the roles of shaping, positioning and supporting, and ensuring that the shape, size and surface quality of the casting meet the requirements.

[0005] It can be seen from the prior art and the above-mentioned iron mold for casting that in the process of casting the casting, there are usually hot spot parts in the upper area of this integral iron mold structure (i.e., a hot spot is an area in the casting where, during the solidification process of the molten iron, due to inconsistent cooling rates, some parts inside the casting solidify more slowly than the surrounding metal. The nodes or local areas in the casting where the solidification is slower than the surrounding metal are usually the last places to cool and solidify). The existing hot spot areas in the casting process will cause thermal stress during the condensation of the casting, which may lead to defects such as casting deformation, cracks, shrinkage porosity, shrinkage cavity, cold shut and gas holes.

[0006] Although currently, for the hot spot phenomenon of the traditional integral iron mold casting mold, the riser feeding process method is usually adopted to reduce it, for some special mold shells, the processability is limited more, and it is usually more difficult to set the riser feeding process method.

[0007] Therefore, it is very difficult to avoid or greatly reduce the casting defects caused by hot spots only by performing riser feeding during the mold casting process, especially for a type of mold with a large number of hot spot areas.

[0008] To this end, the utility model designs a process equipment dedicated to eliminating shrinkage porosity of castings for the problem of hot spots of castings in the existing casting process of casting iron molds with sand coating, so as to better match the existing casting iron mold to complete the casting of castings. Summary of the Utility Model

[0009] One of the technical solutions adopted by the utility model to solve the above technical problems is: a process equipment for eliminating shrinkage porosity of castings. The process equipment is used to be installed in a chill hole that penetrates through and is opened at the hot spot area position of a casting iron mold. The process equipment includes a chill pipe. The inner end of the chill pipe is fitted and inserted into the chill hole that penetrates through. The inner end of the chill pipe is blocked. The inner end surface of the chill pipe matches the inner surface at the corresponding position of the casting iron mold. In the casting and pouring state, the inner end of the chill pipe is used to contact the molding sand in the casting iron mold to accelerate the cooling speed of the molten iron in the hot spot area. An inner pipe cavity is arranged inside the chill pipe, and an end plugging member is screwed at the outer port of the inner pipe cavity.

[0010] In any of the above solutions, preferably, the inner surface contour of the chill hole that penetrates through matches the outer surface contour of the chill pipe.

[0011] In any of the above solutions, preferably, an insertion pipe portion is arranged at the inner end of the chill pipe, and an outer screw pipe portion is arranged at the outer end. A tapered pipe portion is arranged between the outer screw pipe portion and the insertion pipe portion. The insertion pipe portion, the outer screw pipe portion and the tapered pipe portion are of an integrally formed structure. An external thread for cooperating with the internal thread on the inner side wall of the chill hole that penetrates through is arranged on the outer side wall of the outer screw pipe portion.

[0012] In any of the above solutions, preferably, a low-temperature coolant is filled in the inner pipe cavity.

[0013] In any of the above solutions, preferably, the end plugging member is used to connect an externally supporting metal water inlet pipe and a metal water return pipe to the inner pipe cavity.

[0014] In any of the above solutions, preferably, the end plugging member includes a plugging cover that is screwed at the port part of the inner pipe cavity. The inner end of the plugging cover extends into the inner pipe cavity. An enlarged diameter portion is integrally formed at the outer end of the plugging cover. A water inlet channel and a water return channel are arranged at intervals on the outer end surface of the enlarged diameter portion. The outer end of the water inlet channel is fixedly connected to the metal water inlet pipe and the two are internally connected. The outer end of the water return channel is fixedly connected to the metal water return pipe and the two are internally connected. The outer ends of the metal water inlet pipe and the metal water return pipe are both connected to a cooling water tank with a pump body outside.

[0015] In any of the above solutions, preferably, the outer diameter of the insertion pipe portion is smaller than the outer diameter of the outer screw pipe portion.

[0016] Preferably, in any of the above solutions, four positioning and disassembly blind holes are evenly spaced along the circumference at the outer end face of the chill pipe.

[0017] Preferably, in any of the above solutions, a chamfered curved surface is provided at the edge of the inner end face of the inner lumen.

[0018] Preferably, in any of the above solutions, the inner ends of the water inlet channel and the water return channel both extend into the interior of the inner lumen.

[0019] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0020] 1. The process equipment designed in the present utility model is mainly used by being installed in the chill through holes opened at the hot spot areas of the casting iron mold. When there are multiple hot spot areas on the casting iron mold, chill through holes are pre-opened at each hot spot area, and one piece of this process equipment is installed and fitted inside each chill through hole, effectively reducing the cooling rate of the molten iron in the hot spot area at the corresponding position.

[0021] 2. The entire process equipment in the present utility model is directly installed and fixed on the corresponding casting iron mold in a quickly detachable manner, and can be quickly installed or disassembled according to the usage requirements during the use process, and the overall operation is simple and fast.

[0022] 3. When in use, the process equipment in the present utility model can accelerate the cooling rate of the molten iron at the hot spot part of the casting iron mold by injecting a coolant into the inner lumen inside, effectively reducing the shrinkage porosity defect caused by the slow cooling of the hot spot area after the casting is formed, and indirectly improving the forming quality of the cast casting.

[0023] 4. After the entire process assembly is installed, the coolant is continuously circulated and transported into the inner lumen through the pump body supporting the cooling water tank to take away the cooling rate of the molten iron inside the hot spot area of the casting iron mold, and further improve the forming quality of the casting in the form of flowing coolant. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the specific embodiments of the present utility model, the drawings required for the specific embodiments will be briefly introduced below. In all the drawings, similar elements or components are generally identified by similar reference numerals. In the drawings, the elements or components are not necessarily drawn to scale.

[0025] Figure 1 It is a cross-sectional view showing the installation state of the process equipment for eliminating shrinkage porosity of the present utility model and the casting iron mold.

[0026] Figure 2 Schematic diagram of the exploded structure of the process equipment for eliminating shrinkage porosity in castings of the present utility model.

[0027] Figure 3 Three-dimensional structure diagram of the chill pipe of the present utility model.

[0028] Figure 4 Partial sectional structure diagram of the chill pipe of the present utility model.

[0029] In the figure, 1 is a casting iron mold; 2 is a hot spot area; 3 is a chill through hole; 4 is a chill pipe; 401 is an inserted pipe part; 402 is an external screw pipe part; 403 is a tapered pipe part; 5 is an inner pipe cavity; 6 is low-temperature coolant; 7 is a metal water inlet pipe; 8 is a metal water return pipe; 9 is a plugging cover; 10 is an enlarged diameter part; 11 is a water inlet channel; 12 is a water return channel; 13 is a positioning and disassembly blind hole; 14 is a rounded surface. Specific implementation mode

[0030] Next, embodiments of the technical solution of the present utility model will be described in detail with reference to the drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present utility model, so they are only examples and cannot be used to limit the protection scope of the present utility model. The specific structure of the present utility model is as Figures 1 - 4 shown in the figure.

[0031] Embodiment 1: A process equipment for eliminating shrinkage porosity in castings, the process equipment is used to be installed in the chill through hole 3 opened at the position of the hot spot area 2 of the casting iron mold 1. The process equipment includes a chill pipe 4. The inner end of the chill pipe 4 is fitted and inserted into the chill through hole 3, and the inner end of the chill pipe 4 is plugged. The inner end surface of the chill pipe 4 matches the inner surface of the corresponding position of the casting iron mold 1. In the casting pouring state, the inner end of the chill pipe 4 is used to contact the molding sand in the casting iron mold 1 to accelerate the cooling speed of the molten iron in the hot spot area 2. An inner pipe cavity 5 is provided inside the chill pipe 4, and an end plugging member is screwed at the outer port of the inner pipe cavity 5. The process equipment for eliminating shrinkage porosity in castings of the present utility model is integrally fixed in the chill through hole 3 opened at the position of the hot spot area 2 of the casting iron mold 1 in a way that can be quickly installed and disassembled, and the number of the process equipment installed is selected according to the number of hot spot areas 2 on the current casting iron mold 1; the number of the process equipment installed is selected as needed to effectively ensure the quality of the casting during the casting and molding of the entire casting iron mold 1; the end plugging member is used to plug the end of the inner pipe cavity 5, so that the coolant stored inside the inner pipe cavity 5 can be concentrated inside the inner pipe cavity 5 to achieve the purpose of indirectly cooling the molten iron at the hot spot part.

[0032] In any of the above solutions, preferably, the inner surface contour of the chill through hole 3 matches the outer surface contour of the chill pipe 4.

[0033] The inner surface profile of the chill through-hole 3 matches the outer surface profile of the chill pipe 4, which can better ensure that after installation, the entire chill pipe 4 can be better matched and installed on the casting iron mold 1 to serve as part of the casting iron mold 1, and at the same time, it can achieve a different cooling rate from the main body of the casting iron mold 1.

[0034] In any of the above solutions, preferably, an insertion pipe portion 401 is provided at the inner end of the chill pipe 4, and an external screw pipe portion 402 is provided at the outer end. A tapered pipe portion 403 is provided between the external screw pipe portion 402 and the insertion pipe portion 401. The insertion pipe portion 401, the external screw pipe portion 402, and the tapered pipe portion 403 are of an integrally formed structure. An external thread for mating with the internal thread on the inner side wall of the chill through-hole 3 is provided on the outer side wall of the external screw pipe portion 402.

[0035] The inner end of the entire structure of the chill pipe 4 adopts a cylindrical insertion pipe portion 401. The inner end of the insertion pipe portion 401 is fitted and inserted into the cylindrical hole part at the inner end of the chill through-hole 3 and extends into the inner cavity of the casting iron mold 1. Among them, the provided tapered pipe portion 403 is in the form of a tapered curved surface to achieve close contact with the corresponding part of the chill through-hole 3.

[0036] When the external screw pipe portion 402 is screwed and connected with the internal thread inside the chill through-hole 3, using a square thread connection can ensure the firmness of the connection, and through the thread connection, the fastening effect of the entire structure can be effectively ensured.

[0037] In any of the above solutions, preferably, a low-temperature coolant 6 is filled in the inner pipe cavity 5.

[0038] The low-temperature coolant 6 can quickly reduce the cooling rate of the molten iron in the hot spot area 2 through the conduction of the side wall at the inner end of the chill pipe 4, effectively eliminating or reducing the casting defect problems caused by hot spots.

[0039] Embodiment 2: Compared with Embodiment 1, the difference in this embodiment is that it further includes the following technical features:

[0040] The end plugging member is used to connect the externally matched metal water inlet pipe 7 and metal water return pipe 8 to the inner pipe cavity 5.

[0041] Preferably, in any of the above solutions, the end plugging member includes a plugging cover 9 threadedly engaged at the port of the inner lumen 5. The inner end of the plugging cover 9 extends into the inner lumen 5. An enlarged diameter portion 10 is integrally formed at the outer end of the plugging cover 9. Water inlet channels 11 and a water return channel 12 are spaced on the outer end face of the enlarged diameter portion 10. The outer end of the water inlet channel 11 is fixedly connected to the metal water inlet pipe 7 and the two are internally connected. The outer end of the water return channel 12 is fixedly connected to the metal water return pipe 8 and the two are internally connected. The outer ends of the metal water inlet pipe 7 and the metal water return pipe 8 are both connected to a cooling water tank with a pump body outside.

[0042] As an option, here the metal water inlet pipe 7 and the metal water return pipe 8 are respectively installed in the water inlet channel 11 and the water return channel 12 of the corresponding plugging cover 9 of the end plugging member to connect the inner lumen 5 with the external cooling water tank. By connecting the inner lumen 5 with the cooling water tank, the coolant can be quickly circulated through the inner lumen 5 to quickly cool the molding sand and molten iron inside the casting iron mold 1, effectively reducing the problem of shrinkage porosity in the casting caused by the hot spot area 2. Among them, the transportation of the coolant is completed by the pump body configured on the cooling water tank as a power member, playing the role of circulating power.

[0043] Preferably, in any of the above solutions, the outer diameter of the insertion pipe portion 401 is smaller than the outer diameter of the external screw pipe portion 402.

[0044] The insertion pipe portion 401 with a small diameter and the external screw pipe portion 402 with a large diameter can better achieve multi-stage plugging of the chill hole 3, thus effectively ensuring the plugging effect.

[0045] Preferably, in any of the above solutions, four positioning and disassembly blind holes 13 are evenly spaced along the circumference at the outer end face of the chill pipe 4.

[0046] When installing or disassembling the entire chill pipe 4, it can be better rotated by inserting the corresponding insertion screw into the positioning and disassembly blind hole 13, and then using the four insertion posts as push rods to achieve the purpose of quick threaded engagement installation.

[0047] Preferably, in any of the above solutions, a rounded surface 14 is provided at the edge of the inner end face of the inner lumen 5.

[0048] The rounded surface 14 provided here can play an effective transitional role and effectively improve the effect of cooling conduction.

[0049] Preferably, in any of the above solutions, the inner ends of the water inlet channel 11 and the water return channel 12 both extend into the inner lumen 5.

[0050] The length that the return water channel 12 extends into the inner lumen 5 is less than the length that the inlet channel 11 extends into the inner lumen 5, which can effectively ensure that the incoming water and the outgoing water can quickly achieve the purpose of impinging heat transfer of the coolant within the inner lumen 5, so that the internal coolant can be effectively drained continuously to achieve the purpose of circulation.

[0051] Specific working principle: The process equipment for eliminating shrinkage porosity of castings in this design is integrally fixed in the chill through-hole 3 opened at the position of the hot spot area 2 of the casting iron mold 1 by a quick-installation and disassembly method, and the number of this process equipment installed is selected according to the number of hot spot areas 2 on the current casting iron mold 1.

[0052] Select the number of this process equipment to be installed as needed to effectively ensure the quality of the casting during the casting of the casting on the entire casting iron mold 1.

[0053] Among them, the provided end plugging member is used to plug the end of the inner lumen 5, so that the coolant stored inside the inner lumen 5 can be concentrated inside the inner lumen 5 to achieve the purpose of indirectly cooling the molten iron at the hot spot part.

[0054] In summary, the process equipment in this utility model is mainly installed and used in the chill through-hole 3 opened at the position of the hot spot area 2 of the casting iron mold 1. When there are multiple hot spot area positions 2 on the casting iron mold 1, a chill through-hole 3 is pre-opened at each hot spot area position 2, and one piece of this process equipment is installed and fitted inside each chill through-hole 3 to effectively reduce the cooling rate of the molten iron in the hot spot area 2 at the corresponding position; the entire process equipment is directly installed and fixed on the corresponding casting iron mold 1 in a quick-disassembly manner, and can be quickly installed or disassembled according to the usage requirements during the use process, and the overall operation is simple and fast. When this process equipment is in use, it can inject coolant into the inner lumen 5 inside to accelerate the cooling rate of the molten iron at the hot spot part of the casting iron mold 1 after pouring molten iron inside the casting iron mold 1, effectively reducing the shrinkage porosity defect of the casting after molding caused by the slow cooling of the hot spot area 2, and indirectly improving the molding quality of the cast casting.

[0055] It can be seen that after the entire process assembly is installed, the pump body supporting the cooling water tank continuously circulates and conveys the coolant into the inner lumen 5 to take away the cooling rate of the molten iron inside the hot spot area 2 of the casting iron mold 1, and further improves the casting molding quality in the form of flowing coolant.

[0056] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention; for those skilled in the art of this technology, any alternative improvement or transformation made to the embodiments of the present invention falls within the protection scope of the present invention.

[0057] Where the present invention is not described in detail, it is the well-known technology of those skilled in the art of this technology.

Claims

1. A process equipment for eliminating shrinkage of castings, the process equipment is used to be installed in a cold iron through hole opened at the hot zone area of ​​a casting iron mold, and is characterized by: The process equipment includes a cold iron pipe, the inner end of which is inserted into the cold iron through hole, the inner end of which is sealed, the inner end surface of which matches the inner surface of the casting iron mold at a corresponding position, and the inner end of which is used to contact the molding sand in the casting iron mold in the casting pouring state to accelerate the cooling speed of the molten iron in the hot zone area. An inner tube cavity is provided inside the cold iron pipe, and an end sealing piece is screwed on the outer port of the inner tube cavity.

2. A process equipment for eliminating casting shrinkage according to claim 1, characterized in that: The inner surface profile of the chill through hole matches the outer surface profile of the chill pipe.

3. A process equipment for eliminating casting shrinkage according to claim 2, characterized in that: The inner end of the cold iron pipe is provided with a plug-in tube portion, and the outer end is provided with an external screw tube portion, a tapered tube portion is provided between the external screw tube portion and the plug-in tube portion, the plug-in tube portion, the external screw tube portion and the tapered tube portion are an integrally formed structure, and an external thread for matching with the internal thread on the inner wall of the cold iron through hole is provided on the outer side wall of the external screw tube portion.

4. A process equipment for eliminating casting shrinkage according to claim 3, characterized in that: The inner tube cavity is filled with low-temperature cooling liquid.

5. The process equipment for eliminating casting shrinkage according to claim 4, characterized in that: The end plugging piece is used to connect the external matching metal water inlet pipe and metal water return pipe to the inner tube cavity.

6. The process equipment for eliminating casting shrinkage according to claim 5, characterized in that: The end sealing member includes a sealing cap threadedly arranged at the port portion of the inner tube cavity, the inner end of the sealing cap extends into the inner tube cavity, the outer end of the sealing cap is integrally formed with an expanded diameter portion, and an inlet channel and a return channel are arranged at intervals on the outer end surface of the expanded diameter portion, the outer end of the inlet channel is fixedly connected to the metal inlet pipe and the two are internally connected, the outer end of the return channel is fixedly connected to the metal return pipe and the two are internally connected, and the outer ends of the metal inlet pipe and the metal return pipe are connected to an external cooling water tank with a pump body.

7. The process equipment for eliminating casting shrinkage according to claim 6, characterized in that: The outer diameter of the insertion tube portion is smaller than the outer diameter of the outer spiral tube portion.

8. The process equipment for eliminating casting shrinkage according to claim 7, characterized in that: Four positioning and disassembly blind holes are evenly spaced along the circumference of the cold iron pipe at the outer end surface.

9. A process equipment for eliminating casting shrinkage according to claim 8, characterized in that: A chamfered curved surface is arranged on the edge of the inner end surface of the inner tube cavity.

10. The process equipment for eliminating casting shrinkage according to claim 9, characterized in that: The inner end of the water inlet channel and the inner end of the water return channel both extend into the interior of the inner tube cavity.

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