Mold core casting mold structure and steel ingot mold transverse casting method

Abstract

The mold core casting mold structure comprises an outer mold and a sand core which are horizontally arranged, and the sand core is horizontally arranged in an inner cavity of the outer mold; the sand core comprises a molding sand structure and a core bar structure, the core bar structure is embedded in the molding sand structure, and the core bar structure further comprises a core bar body and a plurality of reinforcing ribs which are fixedly connected to the outer surface of the core bar body and are arranged in the axial direction of the core bar body; a cavity with a transverse casting mold is formed between the sand core and the inner cavity; according to the mold core casting mold structure, at least two pouring channels are formed in the two sides of the upper portion of an outer mold, and the pouring channels are communicated with end openings in the two sides of a mold cavity respectively. According to the mold core casting mold structure provided by the invention, molten iron can be poured into the ports on the two sides of the mold cavity at the same time, and the unique design of the core bar structure is matched, so that the pouring speed of the high-temperature molten iron is increased, and the temperature uniformity of the molten iron in the mold cavity can be ensured; the problem that a sand core with a large height-diameter ratio and an ultra-long length is prone to deformation due to uneven heating in a high-temperature molten iron environment is effectively solved.

Description

Technical Field

[0001] The invention relates to the technical field of steel ingot mold casting, and in particular to a core casting structure and a steel ingot mold transverse casting method. Background Art

[0002] As an important tool for steel mills to cast molten steel, the steel ingot mold is a casting model for molten steel to be poured and formed. Therefore, the quality of the steel ingot mold has an extremely important influence on the quality of casting molding.

[0003] At present, the market demand for large and medium-sized steel ingots is still considerable. However, large and medium-sized steel ingots are relatively heavy and large in volume, and have a large height-to-diameter ratio. Correspondingly, the weight, volume and height-to-diameter ratio of the steel ingot mold used for die casting are also large. Therefore, there are many problems when using the current traditional steel ingot mold vertical casting method for casting production.

[0004] Especially when casting large and medium-sized steel ingot molds with a large height-to-diameter ratio, the weight and height-to-diameter ratio of the sand core are large, and the sand core is relatively slender. During the high-temperature molten iron pouring process, the sand core of the vertical casting of the steel ingot mold is often easily deformed due to uneven heating, and the sand core is also easily deformed under the action of gravity, which seriously affects the inner cavity straightness and the inner and outer surface quality of the steel ingot mold; and when the sand core is deformed to a certain extent, it cannot be used again and is scrapped, which greatly shortens the service life of the sand core. In addition, the casting of large and medium-sized steel ingot molds with a large height-to-diameter ratio is often limited by on-site conditions and equipment.

[0005] Therefore, the current traditional ingot mold vertical casting method can no longer meet the casting technology requirements of large and medium-sized ingot molds, and cannot guarantee the inner cavity straightness and inner and outer surface quality of the ingot mold. Summary of the invention

[0006] In view of the defects of the above-mentioned prior art, the purpose of this application is to provide a core casting structure and a horizontal casting method for an ingot mold, aiming to solve the problem that the traditional vertical casting method of an ingot mold easily causes deformation of the slender sand core during the casting process of a large aspect ratio and an ultra-long ingot mold.

[0007] To achieve the above purpose, the embodiment of the present application adopts the following technical solution:

[0008] In a first aspect, an embodiment of the present application provides a core casting structure, comprising:

[0009] External mold;

[0010] A sand core is horizontally arranged in the inner cavity of the outer mold, the sand core comprises a molding sand structure and a core bone structure, the core bone structure is embedded in the molding sand structure, the core bone structure comprises a core bone body and a plurality of reinforcing ribs fixedly connected to the outer surface of the core bone body and arranged along the axial direction of the core bone body; a mold cavity with a transverse casting mold is formed between the sand core and the inner cavity;

[0011] At least two pouring channels are respectively arranged on both sides of the upper part of the outer mold, and the two pouring channels are respectively communicated with the ports on both sides of the cavity.

[0012] In some embodiments, the number of the reinforcing ribs is six, and the six reinforcing ribs are arranged at intervals on the outer surface extending along the length direction of the core bone body.

[0013] In some embodiments, the outer mold includes an outer mold upper mold and an outer mold lower mold, the outer mold upper mold is tightly fitted to the upper part of the outer mold lower mold, and the inner cavity is formed between the outer mold upper mold and the outer mold lower mold.

[0014] In some embodiments, the core casting structure further comprises:

[0015] A pouring cup is arranged on one side of the upper plane of the outer mold;

[0016] A sprue, one end of which is connected to the pouring cup;

[0017] An ingrate, one end of which is connected to the other end of the sprue, and the other end of which is connected to a side port of the cavity;

[0018] The pouring cup, the sprue and the inner runner constitute a pouring channel.

[0019] In some embodiments, a plurality of risers are further provided on the upper portion of the outer mold, and the plurality of risers are arranged at intervals within the lateral range of the cavity.

[0020] In some embodiments, at least two graphite coating layers are provided on the inner surface of the mold cavity and / or the surface of the sand core.

[0021] In a second aspect, an embodiment of the present application provides a method for horizontal casting of a steel ingot mold, wherein the method adopts the core casting structure provided in the above embodiment for casting, and comprises:

[0022] Making an outer mold, and forming at least two pouring channels on the upper part of the outer mold;

[0023] Making a core structure with multiple reinforcing ribs and making a sand core;

[0024] The outer mold and the sand core are assembled to form a cavity with a transverse casting mold, and the two pouring channels are respectively connected to the ports on both sides of the cavity;

[0025] The molten iron is passed through the two pouring channels and poured into the mold cavity at the same time to form a steel ingot mold precast body;

[0026] After the steel ingot mold precast body is kept warm, unpacked and inspected, the steel ingot mold is obtained.

[0027] In some embodiments, the making of the outer mold further comprises:

[0028] Making an outer mold upper mold and an outer mold lower mold;

[0029] Filling molding sand between the mold of the outer mold lower mold and the outer mold sand box, and demoulding after the molding sand is solidified to obtain the outer mold lower mold;

[0030] Filling the molding sand between the mold and the outer mold sand box, and demoulding after the molding sand is solidified to obtain the outer mold upper mold;

[0031] The outer mold upper mold is fastened and fitted to the upper part of the outer mold lower mold to form an inner cavity for accommodating the sand core.

[0032] In some embodiments, the making of the sand core further comprises:

[0033] Making a core shell to form a core shell structure including a core shell body, a first shell body and a second shell body;

[0034] The first shell is fastened and attached to the lower part of the core shell body in the vertical direction to form an accommodating space for accommodating the core bone structure;

[0035] When the molding sand is filled into the accommodating space to the upper end plane of the first shell, the second shell is fastened and fitted to the upper part of the core shell body in the vertical direction, and the molding sand is continued to be filled to the upper end plane of the second shell. After the molding sand is solidified, the shell is removed to obtain the sand core.

[0036] In some embodiments, based on the steel ingot mold transverse casting method provided in the above embodiments, marks are formed at both ends of one of the reinforcing ribs, and when the sand core is used for the first time, the reinforcing rib with the mark is vertically upward; each time the sand core is reused, the reinforcing rib with the mark is alternately flipped 180 degrees.

[0037] Compared with the prior art, this application has the following beneficial effects:

[0038] The core casting structure provided in the embodiment of the present application adopts a horizontal outer mold, and the sand core is horizontally arranged in the outer mold, so that a cavity structure with a transverse casting mold is formed between the inner cavity of the outer mold and the sand core, and at least two pouring channels are provided on both sides of the upper part of the outer mold, so that molten iron can be poured into the ports on both sides of the cavity at the same time. Combined with the unique design of the core bone structure, the pouring speed of the high-temperature molten iron is improved, and the uniformity of the molten iron temperature in the cavity is ensured, which effectively solves the problem that the sand core with a large aspect ratio and an extra-long sand core is easily deformed due to uneven heating in a high-temperature molten iron environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 A schematic cross-sectional view of a core casting structure provided in some embodiments of the present application;

[0040] Figure 2 A schematic cross-sectional view of a core bone structure provided in some embodiments of the present application;

[0041] Figure 3 A radial schematic diagram of a core bone structure provided in some embodiments of the present application;

[0042] Figure 4 A schematic cross-sectional view of the lower mold of the outer mold provided in some embodiments of the present application;

[0043] Figure 5 A schematic cross-sectional view of a core-shell structure provided in some embodiments of the present application;

[0044] Figure 6 A radial schematic diagram of a core-shell structure provided for some embodiments of the present application;

[0045] Figure 7 A schematic diagram of a process flow of a steel ingot mold transverse casting method provided in some embodiments of the present application;

[0046] Figure 8 A schematic diagram of the external mold manufacturing process provided for some embodiments of the present application;

[0047] Fig. 9 A schematic diagram of a sand core manufacturing process provided in some embodiments of the present application;

[0048] Fig.10 A schematic diagram of the reinforcing rib marks being alternately flipped 180° when the sand core is reused according to some embodiments of the present application;

[0049] Fig.11 This is a schematic diagram of the sand core thermal stress simulation provided in Example 1 of the present application.

[0050] Description of reference numerals:

[0051] 1 pouring cup 8b outer mold lower mold

[0052] 2 Riser 9 Mold

[0053] 3 Cavity 10 Bottom plate

[0054] 4 Sand core 11 Positioning pin

[0055] 5 Core-bone structure 12 Core-shell body

[0056] 5a Core body 13 First shell

[0057] 5b Reinforcement rib 14 Second shell

[0058] 6 Sprue 15 S mark

[0059] 7 Ingate 16 Pouring channel

[0060] 8 External mold 17 External mold sand box

[0061] 8a External mold upper mold DETAILED DESCRIPTION

[0062] The following is an explanation of the implementation of the present application by means of specific embodiments. People familiar with the technology can easily understand other advantages and effects of the present application from the contents disclosed in this specification.

[0063] It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other. The present application will be described in detail below with reference to the drawings and in combination with the embodiments. In order to enable those skilled in the art to better understand the present application scheme, the technical scheme in the embodiments of the present application will be clearly and completely described below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only embodiments of a part of the present application, not all embodiments. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in the field without making creative work should fall within the scope of protection of the present application.

[0064] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0065] It should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0066] In a first aspect of the embodiments of the present application, a core casting structure is provided, such as Figure 1 As shown, in some embodiments,

[0067] It includes an outer mold 8, a sand core 4 and at least two pouring channels 16. The sand core 4 is horizontally arranged in the inner cavity of the outer mold 8. The sand core 4 includes a molding sand structure and a core bone structure 5. The core bone structure 5 is embedded in the molding sand structure. The core bone structure 5 includes a core bone body 5a and a plurality of reinforcing ribs 5b fixedly connected to the outer surface of the core bone body 5a and arranged axially along the core bone body 5a; a cavity 3 with a transverse casting mold is formed between the sand core 4 and the inner cavity of the outer mold 8; two pouring channels 16 are respectively arranged on both sides of the upper part of the outer mold 8, and the two pouring channels 16 are respectively connected to the ports on both sides of the cavity 3.

[0068] In the core casting structure provided in the embodiment of the present application, the outer mold 8 is horizontally arranged, and the sand core 4 is horizontally arranged in the inner cavity of the outer mold 8, so that a cavity 3 with a transverse casting mold is formed between the inner cavity of the outer mold 8 and the sand core 4, and at least two pouring channels 16 are provided on both sides of the upper part of the outer mold 8, so that molten iron can be poured into the ports on both sides of the cavity 3 at the same time, which increases the pouring speed of the high-temperature molten iron and ensures the uniformity of the temperature of the molten iron in the cavity 3, thereby effectively avoiding the problem of easy deformation of the sand core 4 with a large aspect ratio and an extra-long length due to uneven heating in a high-temperature molten iron environment.

[0069] In the mold core casting structure provided in the embodiment of the present application, the core bone structure 5 also includes a core bone body 5a, and a plurality of reinforcing ribs 5b fixedly connected to the outer surface of the core bone body. The unique design and use of the core bone structure can effectively improve the overall strength and deformation resistance of the sand core 4 in a high-temperature molten iron environment. At the same time, the use of a transverse casting structure also avoids the problem of easy deformation of the slender sand core 4 due to its heavy weight, and effectively solves the problem of easy deformation of the traditional sand core with a large aspect ratio and an extra-long length during the casting process of the steel ingot mold, thereby ensuring the inner cavity straightness and the inner and outer surface quality of the steel ingot mold during the casting process.

[0070] like Figure 3 As shown, in some embodiments, the number of the reinforcing ribs 5b is six, and the six reinforcing ribs 5b are arranged at intervals on the outer surface extending along the length direction of the core bar body 5a.

[0071] In this embodiment, the cross-sectional shape of the reinforcing rib 5b is a rectangle, so that the reinforcing rib 5b can form a stable connection with the core body 5a, ensuring the strength and anti-deformation ability of the overall structure. In this embodiment, in order to better improve the strength and anti-deformation ability of the core structure 5, the reinforcing rib 5b can be fixedly connected to the outer surface of the core body 5a by welding or integral forming.

[0072] In some embodiments, the cross-sectional shape of the reinforcing rib 5b can also be a circle or a trapezoid. Of course, the cross-sectional shape of the reinforcing rib 5b can also be other shapes as long as it can improve the overall performance of the core bone structure 5. Therefore, in practical applications, the cross-sectional shape of the reinforcing rib 5b is not limited in any way.

[0073] In some embodiments, according to actual casting needs, other casting channels 16 can be provided between the upper sides of the outer mold 8. For example, another casting channel 16 can be provided in the middle of the upper part of the outer mold 8, so that three casting channels 16 are formed in the upper part of the entire outer mold 8, which can further increase the casting speed of the molten iron, ensure that the temperature of the molten iron in the cavity 3 is more uniform, and make the heating condition of the elongated sand core 4 more uniform as a whole, so that it is not easy to deform due to uneven heating.

[0074] In the embodiment of the present application, the outer mold 8 adopts a structural design of horizontal middle parting and split molding, which is conducive to the convenience of placing the large aspect ratio and super long sand core 4.

[0075] like Figure 1 and 4 As shown, in some embodiments, the outer mold 8 includes an outer mold upper mold 8a and an outer mold lower mold 8b (in the embodiment of the present application, the outer mold upper mold 8a and the outer mold lower mold 8b have the same modeling structure, so the modeling schematic diagram of the outer mold upper mold 8a is not shown), and the outer mold upper mold 8a is fastened to the upper part of the outer mold lower mold 8b, so that the outer mold upper mold 8a and the outer mold lower mold 8b together constitute an outer mold 8 with an inner cavity, and the inner cavity is used to accommodate the sand core 4.

[0076] like Figure 4 As shown, in the embodiment of the present application, the outer mold upper mold 8a and the outer mold lower mold 8b adopt a structural design of intermediate parting and split molding, so the mold 9 used for molding the outer mold upper mold 8a or the outer mold lower mold 8b only needs to be made half, which is beneficial to reducing the production cost of the mold 9.

[0077] like Figure 1As shown, in some embodiments, a pouring cup 1 is provided on one side of the upper plane of the outer mold upper mold 8a. A sprue 6 is provided at the lower end of the pouring cup 1, one end of which is connected to the lower end of the pouring cup 1; an entgate 7 is also provided at the lower end of the sprue 6, one end of which is connected to the other end of the sprue 6, and the other end of the entgate 7 is connected to a port on one side of the cavity 3, so that the pouring cup 1, the sprue 6 and the entgate 7 together form a pouring channel 16.

[0078] like Figure 1 As shown, similarly, a pouring cup 1 is provided on the other side of the upper plane of the outer mold 8a, and a sprue 6 is provided at the lower end of the pouring cup 1, one end of the sprue 6 is interconnected with the lower end of the pouring cup 1; an entgate 7 is also provided at the lower end of the sprue 6, one end of the entgate 7 is interconnected with the other end of the sprue 6, and the other end of the entgate 7 is interconnected with a port on one side of the cavity 3, so that the pouring cup 1, the sprue 6 and the entgate 7 together constitute another pouring channel 16.

[0079] In the embodiment of the present application, according to the actual pouring needs, a third pouring channel 16 may be provided, and the same pouring channel 16 structure as mentioned above may be adopted, which will not be described again here.

[0080] In an embodiment of the present application, the pouring channel 16 adopts a segmented structure, wherein the inner diameter dimensions of the main channels of the straight runner 6 and the ingrowth 7 may be the same or different; in order to better control the flow rate of the high-temperature molten iron in the pouring channel and ensure the uniformity of the temperature of the molten iron in the mold cavity, the inner diameter dimension of the main channel of the ingrowth 7 may be designed to be smaller than the inner diameter dimension of the main channel of the straight runner 6.

[0081] like Figure 1 As shown, in some embodiments, a plurality of risers 2 for eliminating impurities and gas are further provided on the upper portion of the outer mold upper mold 8a. The plurality of risers 2 are arranged at intervals on the upper portion of the outer mold upper mold 8a and in the lateral range of the mold cavity 3. Therefore, in the mold cavity 3 using the lateral casting mold, it is more conducive for impurities and gas to float into the risers 2, which can further improve the molding quality of the ingot mold.

[0082] In some embodiments, at least two layers of graphite coating are provided on the inner surface of the cavity 3 and the outer surface of the sand core 4 to effectively isolate the high-temperature molten iron from direct contact with the inner surface of the cavity 3 and the outer surface of the sand core 4, thereby ensuring the inner surface quality of the ingot mold.

[0083] In the embodiment of the present application, the number of graphite coating layers applied depends on the roughness of the inner surface of the cavity 3 and the outer surface of the sand core 4; if the roughness of the inner surface of the cavity 3 and the outer surface of the sand core 4 is larger, more graphite coating layers can be applied.

[0084] In order to further verify the overall strength and deformation resistance of the sand core 4 provided in the embodiment of the present application in a high-temperature molten iron environment, the embodiment of the present application also conducted a thermal stress simulation test on the sand core 4 to verify whether the deformation of the sand core 4 can meet the casting technical requirements in a high-temperature pouring environment.

[0085] In a second aspect of the embodiments of the present application, a method for horizontal casting of a steel ingot mold is provided, wherein the casting is performed using the core casting structure provided in the above embodiments, such as Figure 7 As shown, the method includes the following steps S10-S50:

[0086] S10: manufacturing an outer mold 8, and forming at least two pouring channels 16 on the upper portion of the outer mold 8;

[0087] S20: manufacturing a core structure 5 having a plurality of reinforcing ribs 5b, and manufacturing a sand core 4;

[0088] S30: Assemble the outer mold 8 and the sand core 4 to form a mold cavity 3 with a transverse casting mold, and make the two pouring channels 16 communicate with the two side ports of the mold cavity 3 respectively;

[0089] S40: The molten iron is poured into the mold cavity 3 through two pouring channels 16 to form a precast steel ingot mold;

[0090] S50: After the steel ingot mold precast body is kept warm, unpacked and inspected, the steel ingot mold is obtained.

[0091] The transverse casting method of the steel ingot mold provided in the embodiment of the present application can simultaneously pour the molten iron into the cavity 3 through at least two pouring channels 16 on both sides of the upper part of the outer mold 8, thereby increasing the pouring speed of the molten iron and ensuring the uniformity of the temperature of the molten iron in the cavity 3, and effectively solving the problem that the sand core 4 with a large aspect ratio and an extra-long length is easily deformed due to uneven heating in the high-temperature molten iron; at the same time, the method adopts transverse casting molding, which effectively avoids the problem that the slender sand core 4 is easily deformed due to its own weight, and thus the overall structure can ensure the straightness of the inner cavity and the quality of the inner and outer surfaces of the steel ingot mold.

[0092] like Figure 8 As shown, in some embodiments, in step S10, making the outer mold 8 further includes the following steps S101-S103:

[0093] S101: making an outer mold upper mold 8a and an outer mold lower mold 8b, filling molding sand between the mold 9 of the outer mold lower mold 8b and the outer mold sand box 17, and demolding after the molding sand is solidified to obtain the outer mold lower mold 8b;

[0094] S102: Fill the molding sand between the mold 9 and the outer mold sand box 17, and demould after the molding sand is solidified to obtain the outer mold upper mold 8a;

[0095] S103: The outer mold upper mold 8a is fastened and fitted to the upper part of the outer mold lower mold 8b to form an inner cavity for accommodating the sand core 4.

[0096] In the embodiment of the present application, the outer mold 8 adopts a structural design of horizontal middle parting and split molding, which is conducive to the convenience of placing the large aspect ratio and extra-long sand core 4; at the same time, since the outer mold upper mold 8a and the outer mold lower mold 8b adopt a structural design of middle parting and split molding, the mold 9 used for molding the outer mold upper mold 8a or the outer mold lower mold 8b only needs to be made half, which is conducive to reducing the production cost of the mold 9.

[0097] like Fig. 9 As shown, in some embodiments, in step S20, making the sand core further includes the following steps S201-S203:

[0098] S201: manufacturing a core shell to form a core shell structure including a core shell body 12, a first shell 13 and a second shell 14;

[0099] S202: The first shell 13 is fastened and attached to the lower part of the core shell body 12 in the vertical direction to form an accommodating space for accommodating the core bone structure 5;

[0100] S203: When the molding sand is filled into the accommodation space to the upper end plane of the first shell 13, the second shell 14 is fastened to the upper part of the core shell body 12 in the vertical direction, and the molding sand is continued to be filled to the upper end plane of the second shell 14. After the molding sand is solidified, the shell is removed to obtain the sand core 4.

[0101] The core-shell structure provided in the embodiment of the present application adopts a split core-shell structure design that combines vertical and horizontal split cores, which improves the operational convenience of placing the ultra-long core bone structure 5, while also improving the compaction uniformity of the medium-sized sand in the inner cavity of the core-shell structure, ensuring the molding quality of the ultra-long sand core with a large aspect ratio.

[0102] like Figure 3 and 10 As shown, in some embodiments, S marks 15 are formed at both ends of one of the reinforcing ribs 5b, and when the sand core 4 is used for the first time, the reinforcing rib 5b with the S mark 15 is vertically upward; and each time the sand core 4 is reused, the reinforcing rib 5b with the S mark 15 is alternately flipped 180 degrees.

[0103] In the ingot mold transverse casting method provided in the embodiment of the present application, by forming S marks 15 at both ends of one of the reinforcing ribs 5b, when the sand core 4 is used for the first time, the reinforcing rib 5b with the S mark 15 is vertically upward; and, each time the sand core 4 is reused, the reinforcing rib 5b with the S mark 15 is alternately flipped 180 degrees, which can effectively offset the upward stress generated by the core structure 5 due to the buoyancy of the high-temperature molten iron during the previous use. Therefore, the number of times the sand core 4 can be reused can be increased, the service life of the sand core 4 can be improved, and the production cost of the sand core 4 can be reduced.

[0104] In order to objectively evaluate the technical effects of the embodiments of the present application, the present application is described in detail below through specific embodiments. However, the embodiments of the present application are not limited to the following specific embodiments, and can be appropriately modified and implemented within the scope of the unchanged main rights.

[0105] Embodiment 1

[0106] Embodiment 1 provides a method for horizontal casting of a steel ingot mold. In this method, an ultra-long round steel ingot mold with a length of 4760 mm, an outer diameter of 915 mm, an inner diameter of 660 mm, and a pouring weight of 13.5 tons is used for horizontal casting, and the core body 5a used is a Q345 seamless steel pipe. The following is a specific method for horizontal casting of the ultra-long round steel ingot mold:

[0107] modeling

[0108] (1) First, make the outer mold lower mold 8b: Figure 4 As shown, the mold 9 is fixedly placed on the bottom plate 10, and the outer mold sand box 17 is fixedly placed on the upper part of the mold 9, and self-hardening furan resin molding sand is filled between the mold 9 and the outer mold sand box 17. During the filling process, the mold 9 is compacted, and after the molding sand is hardened, the outer mold sand box 17 is turned over and demolded by using a mold hook to obtain the outer mold lower mold 8b;

[0109] Then make the shape of the outer mold upper mold 8a: in this embodiment (the shape structure of the outer mold upper mold 8a and the outer mold lower mold 8b is the same, so the shape schematic diagram of the outer mold upper mold 8a is not shown), according to the process requirements, five riser molds for making five risers 2 respectively are evenly placed on the upper part of the mold 9, a ceramic tube pouring system is placed on both sides of the mold 9, and molding sand is filled between the mold 9 and the outer mold sand box 17. During the filling process, the mold 9 is rammed axially. After the molding sand hardens, the five riser molds are taken out first, and then the outer mold sand box 17 is turned over and demolded using a demolding hook to obtain the outer mold upper mold 8a.

[0110] After the outer mold upper mold 8a and the outer mold lower mold 8b are trimmed, at least two layers of graphite coating are coated on the inner cavity surfaces of the outer mold upper mold 8a and the outer mold lower mold 8b to fill the pits between the sand particles.

[0111] (2) Making sand core 4: First, make the core structure 5, such as Figure 2 and 3 As shown, six reinforcing ribs 5b are fixedly arranged on the outer surface of the core body 5a along the axial direction of the core body 5a, and S marks 15 are made at both ends of one of the reinforcing ribs 5b to obtain the core structure 5.

[0112] Then make the core shell, such as Figure 5 and Figure 6 As shown, a core-shell structure including a core-shell body 12, a first shell 13 and a second shell 14 is formed;

[0113] The first shell 13 is fastened and attached to the lower part of the core shell body 12 in the vertical direction to form an accommodation space for accommodating the core bone structure 5;

[0114] When the molding sand is filled into the accommodating space to the upper end plane of the first shell 13, the second shell 14 is fastened and fitted to the upper part of the core shell body 12 in the vertical direction, and the molding sand is continued to be filled to the upper end plane of the second shell 14. After the molding sand is solidified, the shell is removed to obtain the sand core 4, and at least two layers of graphite coating are provided on the surface of the sand core 4 to fill the pits between the sand grains.

[0115] Packing box

[0116] like Figure 1 and 4 As shown, before packing, check whether the outer mold upper mold 8a, the outer mold lower mold 8b and the sand core 4 are complete, and clean the mold cavity 3;

[0117] Before closing the box, two layers of sealing strips are placed on the core heads on both sides of the lower mold 8b of the outer mold. After closing the box, check whether the gaps between the core heads of the upper mold 8a and the lower mold 8b of the outer mold and the core heads of the sand core 4 are consistent;

[0118] Before closing the box, positioning pins 11 are placed at the positioning holes of the outer mold lower mold 8b, and two layers of sealing strips are placed on the upper part of the core heads on both sides to compact them. Two layers of sealing strips are placed around the outer mold upper mold 8a and the outer mold lower mold 8b along the periphery of the mold cavity 3 to prevent fire.

[0119] When closing the box, the core head of the sand core 4, the core heads on both sides of the outer mold upper mold 8a, the core heads on both sides of the outer mold lower mold 8b, the positioning holes of the outer mold upper mold 8a, the positioning holes of the outer mold lower mold 8b and the positioning pins 11 are fully matched to complete the positioning;

[0120] After positioning is completed, the mold is closed, and after closing, the outer mold upper mold 8a and the outer mold lower mold 8b are fastened with bolts, and pouring cups 1 are placed at the positions of the two side straight gates 6 on the upper plane of the outer mold upper mold 8a to form a core casting structure with at least two pouring channels 16 and a horizontal casting cavity 3.

[0121] The smelting is carried out in a medium frequency furnace. The raw materials used are cast pig iron, pure scrap steel, 75 ferrosilicon and 65 ferromanganese, supplemented with carburizer. The ingredients are prepared according to the ingredient list and added into the medium frequency furnace in the order of pig iron (carburizer) - scrap steel - ferrosilicon - ferromanganese for smelting. After melting, the furnace is analyzed at 1300℃ ~ 1350℃. If qualified, it is taken out of the furnace at 1330℃ ~ 1380℃ to obtain pre-cast molten iron.

[0122] pouring

[0123] During pouring, two ladles are used to pour the horizontal casting cavity 3 on both sides at the same time, and the pouring temperature is controlled between 1260℃ and 1300℃; the pouring process adopts fast first and slow later, first quickly filling the cavity 3, with the molten iron always filling about half of the pouring cup as the standard; after the molten iron floats to the riser, it is slowly poured, with the molten iron flowing continuously as the standard, until the riser is full, and then a heat preservation agent is placed in the riser to obtain an ultra-long circular steel ingot mold casting body.

[0124] Insulation

[0125] The super-long round ingot mold casting body is kept warm in situ for not less than 48 hours.

[0126] Unpacking and finishing

[0127] First remove the upper mold, then lift the extra-long round steel mold out of the lower mold, lay it flat, and air cool it to room temperature;

[0128] Remove the pouring system and riser 2 by knocking one by one, and then clean the molding sand on the inner and outer surfaces of the round steel mold until it is completely cleaned to obtain the ingot template.

[0129] test

[0130] The chemical composition, size and internal and external surface quality of the steel ingot mold are inspected according to the drawings, technical requirements and standards, and finally a steel ingot mold product of qualified quality is obtained.

[0131] In the first embodiment, a thermal stress simulation test was conducted on the sand core. Fig.11 This is a schematic diagram of the sand core thermal stress simulation provided in the first embodiment.

[0132] like Fig.11 As shown, in the thermal stress simulation test, the deformation of the core bone of the sand core is only 0.8 mm at 400°C, which meets the technical requirement of steel ingot mold casting that the deformation of the core bone is ≤ 2 mm at 400°C. From the thermal stress simulation test, it can be seen that the sand core 4 provided in the embodiment of the present application effectively solves the problem that the traditional sand core with a large aspect ratio and an extra-long length is prone to deformation during the steel ingot mold casting process, and can ensure the inner cavity straightness and the inner and outer surface quality of the steel ingot mold.

[0133] The horizontal casting method of the steel ingot template provided in the above-mentioned embodiment 1 effectively solves the problem that the traditional sand core with a large aspect ratio and extra-long length is easily deformed due to uneven heating in a high-temperature molten iron environment, thereby ensuring the inner cavity straightness and inner and outer surface quality of the extra-long steel ingot mold.

[0134] What is described above is only a specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any variation, modification or equivalent substitution made by those skilled in the art without departing from the technical concept of the present application, and all embodiments obtained, shall fall within the scope of protection of the claims of the present application.

Claims

1. A core casting structure, characterized in that: include: External mold; A sand core is horizontally arranged in the inner cavity of the outer mold, the sand core comprises a molding sand structure and a core bone structure, the core bone structure is embedded in the molding sand structure, the core bone structure comprises a core bone body and a plurality of reinforcing ribs fixedly connected to the outer surface of the core bone body and arranged along the axial direction of the core bone body; a mold cavity with a transverse casting mold is formed between the sand core and the inner cavity; At least two pouring channels are respectively arranged on both sides of the upper part of the outer mold, and the two pouring channels are respectively communicated with the ports on both sides of the cavity.

2. The core casting structure according to claim 1, characterized in that: The number of the reinforcing ribs is six, and the six reinforcing ribs are arranged at intervals on the outer surface extending along the length direction of the core body.

3. The core casting structure according to claim 1, characterized in that: The outer mold comprises an outer mold upper mold and an outer mold lower mold. The outer mold upper mold is tightly fitted to the upper part of the outer mold lower mold. The inner cavity is formed between the outer mold upper mold and the outer mold lower mold.

4. The core casting structure according to claim 3, characterized in that: Also includes: A pouring cup is arranged on one side of the upper plane of the outer mold; A sprue, one end of which is connected to the pouring cup; An ingrate, one end of which is connected to the other end of the sprue, and the other end of which is connected to a side port of the cavity; The pouring cup, the sprue and the inner runner constitute a pouring channel.

5. The core casting structure according to claim 1, characterized in that: A plurality of risers are also provided on the upper portion of the outer mold, and the plurality of risers are arranged at intervals in the lateral range of the cavity.

6. The core casting structure according to claim 1, characterized in that: At least two graphite coating layers are provided on the inner surface of the mold cavity and / or the surface of the sand core.

7. A method for horizontal casting of steel ingot mold, characterized in that: The casting is performed using the core casting structure according to any one of claims 1 to 6, comprising: Making an outer mold, and forming at least two pouring channels on the upper part of the outer mold; Making a core structure with multiple reinforcing ribs and making a sand core; The outer mold and the sand core are assembled to form a cavity with a transverse casting mold, and the two pouring channels are respectively connected to the ports on both sides of the cavity; The molten iron is passed through the two pouring channels and poured into the mold cavity at the same time to form a steel ingot mold precast body; After the steel ingot mold precast body is kept warm, unpacked and inspected, the steel ingot mold is obtained.

8. The method for horizontal casting of steel ingot mold according to claim 7, characterized in that: The making of the outer mold also includes: Making an outer mold upper mold and an outer mold lower mold; Filling molding sand between the mold of the outer mold lower mold and the outer mold sand box, and demoulding after the molding sand is solidified to obtain the outer mold lower mold; Filling the molding sand between the mold and the outer mold sand box, and demoulding after the molding sand is solidified to obtain the outer mold upper mold; The outer mold upper mold is fastened and fitted to the upper part of the outer mold lower mold to form an inner cavity for accommodating the sand core.

9. The method for horizontal casting of steel ingot mold according to claim 7, characterized in that: The sand core making also includes: Making a core shell to form a core shell structure including a core shell body, a first shell body and a second shell body; The first shell is fastened and attached to the lower part of the core shell body in the vertical direction to form an accommodating space for accommodating the core bone structure; When the molding sand is filled into the accommodating space to the upper end plane of the first shell, the second shell is fastened and fitted to the upper part of the core shell body in the vertical direction, and the molding sand is continued to be filled to the upper end plane of the second shell. After the molding sand is solidified, the shell is removed to obtain the sand core.

10. The method for horizontal casting of steel ingot mold according to any one of claims 7 to 9, characterized in that: Marks are formed at both ends of one of the reinforcing ribs. When the sand core is used for the first time, the reinforcing rib with the mark is vertically upward; each time the sand core is reused, the reinforcing rib with the mark is alternately flipped 180 degrees.

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