Cylinder body sand core manufacturing mold and cylinder body sand core manufacturing method

Abstract

The present application discloses a cylinder block sand core manufacturing mold and a cylinder block sand core manufacturing method. The cylinder block sand core manufacturing mold includes a mold body and a sand core inner shell. The mold body includes a side wall forming frame and two circular hole forming frames. Each circular hole forming frame and the side wall forming frame are provided with a detachable connection structure. The internal cavity of the side wall forming frame and the internal cavities of all circular hole forming frames are combined to form a cavity that matches the shape of the cylinder block cavity. The inner wall of the circular hole forming frame is provided with a piston module for compensating for the shrinkage deformation of the sand core. The edge of the side wall forming frame is provided with a first bolt for adjusting the pressure stress of the sand core. The sand core inner shell is located in the cavity. The axial end face of the sand core inner shell is provided with an annular slot for installing an end face protection cover. The end face protection cover includes an annular mounting plate that matches the annular slot. One end of the annular mounting plate extends radially outward to form a protective plate that matches the circular hole shape of the circular hole forming frame.

Description

Technical Field

[0001] The present application relates to the technical field of casting technology, and in particular to a cylinder sand core manufacturing mold and a cylinder sand core manufacturing method. Background Art

[0002] The cylinder block is the core component of a marine diesel engine. The casting quality of the cylinder block directly determines the service life of the diesel engine, especially the circular hole areas at the upper and lower ends of the internal cavity of the cylinder block, which are used to fix the cylinder liner. The circular hole area serves as the axial fixing reference surface of the cylinder liner and must withstand high pressure. The circular hole area must not have any casting defects such as slag inclusions, sand inclusions, shrinkage, cracks, etc. At the same time, the installation of the cylinder liner directly affects the sealing of the combustion chamber and the movement of the piston. Therefore, the quality of the sand core production of the cylinder block is crucial. The quality of the cylinder block sand core will affect the overall performance of the diesel engine. Summary of the Invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a cylinder sand core manufacturing mold and a cylinder sand core manufacturing method, which can improve the manufacturing quality of the cylinder sand core.

[0004] In a first aspect, an embodiment of the present application provides a mold for manufacturing a cylinder sand core, comprising:

[0005] A mold body, comprising a sidewall forming frame and two circular hole forming frames, each of the circular hole forming frames being provided with a first connecting structure at the bottom, an axial end surface of the sidewall forming frame being provided with a second connecting structure for detachably connecting to the first connecting structure, an internal cavity of the sidewall forming frame and the internal cavities of all the circular hole forming frames being combined to form a mold cavity that matches the shape of the cylinder body cavity, an inner wall of the circular hole forming frame being provided with a piston module for compensating for shrinkage deformation of the sand core, and an edge of the sidewall forming frame being provided with a first bolt for adjusting the pressure on the sand core;

[0006] A sand core liner is located in the mold cavity, and an annular slot for installing an end face protection cover is provided on the axial end face of the sand core liner. The end face protection cover includes an annular mounting plate matching the annular slot, and one end of the annular mounting plate extends radially outward to form a protective plate matching the circular hole shape of the circular hole forming frame.

[0007] In the cylinder block sand core manufacturing mold provided in an embodiment of the present application, the side wall forming frame and the circular hole forming frame are respectively embedded with a first cooling pipe that surrounds the internal cavity.

[0008] In the cylinder sand core manufacturing mold provided in an embodiment of the present application, the outer side wall of the sand core inner shell is provided with a plurality of sand hanging parts, and the sand hanging parts include sand hanging grooves and sand hanging protrusions.

[0009] In the cylinder sand core manufacturing mold provided in an embodiment of the present application, the sand hanging protrusion located in the outer wall area corresponding to the circular hole forming frame includes a first protrusion and a second protrusion, and the outward protrusion height of the first protrusion is greater than the outward protrusion height of the second protrusion to fix different resin sand layers.

[0010] In the cylinder sand core manufacturing mold provided in the embodiment of the present application, the sand core inner shell is hollow, and a plurality of exhaust holes penetrating the side wall of the sand core inner shell are opened.

[0011] In the cylinder block sand core manufacturing mold provided in an embodiment of the present application, a plurality of reinforcing ribs are axially arranged on the inner wall of the sand core liner, and the reinforcing ribs extend from one axial end face of the sand core liner to the other axial end face.

[0012] In the cylinder block sand core manufacturing mold provided in an embodiment of the present application, a second cooling pipe is provided on the inner wall of the sand core liner, and the second cooling pipe is fixed on the side wall of the reinforcing rib.

[0013] In the cylinder sand core manufacturing mold provided in an embodiment of the present application, the sand core inner shell includes a middle core bone corresponding to the position of the side wall forming frame, and a head core bone corresponding to the position of the circular hole forming frame respectively. The head core bone is fixed to the two ends of the middle core bone by bolts respectively, and the head core bone is provided with a magnetic structure for disassembling the sand core inner shell.

[0014] In the second aspect, an embodiment of the present application provides a method for making a cylinder sand core, which is applied to the cylinder sand core making mold as described in any embodiment of the first aspect above, and the method includes: installing the end face protection cover on the annular slot at one end of the sand core inner shell, and sleeve one of the circular hole forming frames on one end of the sand core inner shell to fix the distance between the sand core inner shell and the circular hole forming frame through the end face protection cover; connecting the side wall forming frame and the other circular hole forming frame to the circular hole forming frame in sequence through the first connecting structure and the second connecting structure; using the first sand mold filler to fill the space between the outer wall of the sand core inner shell and the inner wall of the mold cavity, starting the piston module and adjusting the first bolt, and then installing the other end face protection cover on the annular slot.

[0015] In the cylinder block sand core manufacturing method provided in an embodiment of the present application, the method further includes: installing the end face protection cover on the annular slot at one end of the sand core inner shell, and sleeve one of the circular hole forming frames on one end of the sand core inner shell to fix the distance between the sand core inner shell and the circular hole forming frame through the end face protection cover; placing a sand layer baffle between the sand core inner shell and the circular hole forming frame, using a first sand mold filler to fill between the outer wall of the sand core inner shell and the sand layer baffle, and then using a second sand mold filler to fill between the sand layer baffle and the inner wall of the circular hole forming frame; taking out the sand layer baffle, and connecting it through the first connection joint. The first sand mold filler is used to fill the space between the side wall forming frame and the outer wall of the sand core inner shell, and the sand layer baffle is placed between the circular hole forming frame and the sand core inner shell that have not been filled with sand. The first sand mold filler is used to fill the space between the outer wall of the sand core inner shell and the sand layer baffle, and then the second sand mold filler is used to fill the space between the sand layer baffle and the inner wall of the circular hole forming frame; the sand layer baffle is taken out, the piston module is started, the first bolt is adjusted, and the other end face protection cover is installed on the annular slot.

[0016] The cylinder block sand core manufacturing mold and cylinder block sand core manufacturing method provided in the embodiments of the present application have at least the following beneficial effects: a split mold is formed by the detachable connection between the side wall forming frame and the circular hole forming frame, and the end face protection cover of the sand core inner shell cooperates with each other, which can accurately adjust the distance between the part of the sand core inner shell and the mold body in the circular hole area, thereby realizing rapid assembly and positioning of the mold while helping to improve the manufacturing quality of the sand core in the circular hole area, and the end face protection cover can ensure the pressure after the sand core is filled in the circular hole area; in addition, the piston module is used to dynamically compensate for the shrinkage deformation of the sand core in the circular hole area, and the first bolt is used to adjust the pressure of the local sand layer, which helps to improve the dimensional consistency of the cylinder block sand core and improve the manufacturing quality of the cylinder block sand core.

[0017] Other features and advantages of the present application will be described in the following description, and in part will become apparent from the description, or will be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained through the structures particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present application is further described below with reference to the accompanying drawings and embodiments;

[0019] Figure 1 1 is a cross-sectional schematic diagram of the combination of the mold body and the sand core liner in the cylinder sand core manufacturing mold provided by an embodiment of the present application;

[0020] Figure 2 1 is a cross-sectional schematic diagram from another perspective of the assembly of the mold body and the sand core liner in the cylinder sand core manufacturing mold provided by an embodiment of the present application;

[0021] Figure 3 This is a top view of the assembly of the mold body and the sand core liner in the cylinder sand core manufacturing mold provided by an embodiment of the present application;

[0022] Figure 4 It is a process diagram of the cylinder sand core manufacturing method provided in an embodiment of the present application.

[0023] Reference numerals:

[0024] 100, module body; 110, circular hole forming frame; 120, side wall forming frame; 130, mold cavity; 200, sand core liner; 210, end face protection cover; 211, sand hanging groove; 212, first raised portion; 213, second raised portion; 214, exhaust hole. DETAILED DESCRIPTION

[0025] This section will describe the specific embodiments of the present application in detail. The preferred embodiments of the present application are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and overall technical solution of the present application, but it cannot be understood as a limitation on the scope of protection of the present application.

[0026] It should be understood that in the description of the embodiments of the present application, if there is a description of "first", "second", etc., it is only for the purpose of distinguishing technical features, and it is not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features. "At least one" means one or more, and "more than one" means two or more. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items.

[0027] In addition, unless otherwise clearly specified and limited, the term "connection / connected" should be understood in a broad sense. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or able to communicate with each other; it can be a direct connection or an indirect connection through an intermediate medium.

[0028] In the description of the embodiments of the present application, the reference terms "one embodiment / implementation", "another embodiment / implementation" or "certain embodiments / implementations", "in the above-mentioned embodiments / implementations" and the like mean that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least two embodiments or implementations disclosed in the present application. In the disclosure of this application, the schematic representation of the above terms does not necessarily refer to the same exemplary embodiment or implementation. It should be noted that although a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in an order different from that in the flowchart.

[0029] The cylinder block is a core component of a marine diesel engine. Therefore, the casting quality of the cylinder block directly determines the service life of the diesel engine. This is particularly important for the casting quality of the circular holes at the upper and lower ends of the cylinder block's internal cavity. These holes serve as the axial fixing reference surfaces for the cylinder liner and must withstand high pressure. Furthermore, the installation of the cylinder liner directly affects the sealing of the combustion chamber and the movement of the piston. Therefore, the quality of the cylinder block's sand core is crucial and will affect the overall performance of the diesel engine.

[0030] In order to at least solve the technical problems existing in the above-mentioned prior art, the present application proposes a cylinder sand core manufacturing mold and a cylinder sand core manufacturing method. The split mold is formed by the detachable connection of the side wall forming frame and the circular hole forming frame, and the end face protection cover of the sand core inner shell cooperates with each other, which can accurately adjust the distance between the part of the sand core inner shell and the mold body in the circular hole area, thereby realizing rapid assembly and positioning of the mold and helping to improve the manufacturing quality of the sand core in the circular hole area. The end face protection cover can ensure the pressure after the sand core is filled in the circular hole area; in addition, the piston module is used to dynamically compensate for the shrinkage deformation of the sand core in the circular hole area, and the first bolt is used to adjust the pressure of the local sand layer, which helps to improve the size consistency of the cylinder sand core and improve the manufacturing quality of the cylinder sand core.

[0031] It should be noted that the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0032] The embodiments of the present application are further described below with reference to the accompanying drawings.

[0033] Reference Figure 1 , Figure 1It is a cross-sectional schematic diagram of the combination of the mold body and the sand core liner 200 in the cylinder sand core manufacturing mold provided by an embodiment of the present application. On the first aspect, the embodiment of the present application provides a cylinder sand core manufacturing mold, and the cylinder sand core manufacturing mold includes a mold body and a sand core liner 200, wherein the mold body adopts a split design, and the mold body can be formed by combining a side wall molding frame 120 and two circular hole molding frames 110. Specifically, the cylinder molding frame corresponds to the circular hole area of ​​the cylinder body, and the side wall molding frame 120 corresponds to the main body area of ​​the cylinder body. That is to say, the cylinder molding frame is used to make the sand core part of the circular hole area of ​​the cylinder body, and the side wall molding frame 120 is used to make the sand core part of the main body area of ​​the cylinder body. The bottom of each circular hole forming frame 110 is provided with a first connecting structure, and the axial end surface of the side wall forming frame 120 is provided with a second connecting structure. The first connecting structure and the second connecting structure can constitute a detachable connection mode, so that the mold body can be assembled or disassembled according to the actual use situation. For example, in the process of making a sand core, it is necessary to accurately adjust the distance between the frame and the sand core liner 200. Therefore, after separately adjusting the distance between the circular hole forming frame 110 and the sand core liner 200, the circular hole forming frame 110 can be assembled or disassembled. The side wall forming frame 120 is installed on the mold body and the distance between the frame and the sand core inner liner 200 is adjusted. After confirming that the distance between the side wall forming frame 120 and the sand core inner liner 200 is correct, the circular hole forming frame 110 is installed on the side wall forming frame 120 and the distance between the frame and the sand core inner liner 200 is adjusted again. At the same time, the detachable split design also facilitates the assembly of the sand core inner liner 200 into the mold body; after the cylinder body sand core is solidified, the detachable connection method can also facilitate the separation of the mold body from the cylinder body sand core. In addition, since the mold body and the sand core inner liner 200 are reusable, and the circular hole forming frame 110 is also provided with a piston module to squeeze the sand mold filler, the circular hole forming frame 110 is prone to wear and deformation, and the casting quality requirements for the circular hole area of ​​the cylinder body are high. Therefore, the design of the split mold can also facilitate the replacement of wearing parts without the need for an overall replacement of the mold body, saving costs.

[0034] It should be noted that the first connecting structure and the second connecting structure can form a positioning pin structure. The first connecting structure on the circular hole forming frame 110 can be a recessed tapered sleeve, and the second connecting structure on the axial end face of the side wall forming frame 120 can be a protruding positioning pin. A through screw hole is provided in both the tapered sleeve and the positioning pin. After the positioning pin is inserted into the tapered sleeve, the screw holes of the tapered sleeve and the positioning pin are aligned. The circular hole forming frame 110 and the side wall forming frame 120 can be fixedly connected by the cooperation of the bolts and the screw holes. At the same time, when the sand mold filling is heated and cured, the high temperature will cause the tapered sleeve to expand slightly, increasing the holding force and ensuring the stability of the split structure of the mold body. When the sand mold filling is cooled, the tapered sleeve contracts, reducing the disassembly resistance and facilitating separation from the cylinder sand core.

[0035] It should be noted that the first connecting structure and the second connecting structure can constitute an elastic snap-fit ​​structure. The first connecting structure on the circular hole forming frame 110 can be a trapezoidal lock groove, the inner wall of which is inlaid with a wear-resistant lining, while the second connecting structure on the axial end face of the side wall forming frame 120 can be a spring steel sheet snap-fit, the snap-fit ​​is provided with an inclined surface structure, and a roller is provided at the end of the snap-fit. After aligning the spring steel sheet snap-fit ​​of the side wall forming frame 120 with the trapezoidal lock groove of the circular hole forming frame 110, the spring steel sheet snap-fit ​​is pushed into the trapezoidal lock groove. The snap-fit ​​roller slides along the inclined surface of the trapezoidal lock groove. The spring steel sheet is compressed and deformed to store energy. After reaching the locked position, the spring steel sheet rebounds, causing the snap-fit ​​to embed into the bottom of the trapezoidal lock groove, thereby achieving a fixed connection between the circular hole forming frame 110 and the side wall forming frame 120. In addition, an unlocking push rod is provided on the outer wall of the side wall forming frame 120. By pressing the unlocking push rod, the spring steel sheet at the bottom of the lock groove is expanded outward to release the buckle, thereby separating the circular hole forming frame 110 from the side wall forming frame 120. It is worth noting that there can be multiple first connecting structures on the circular hole forming frame 110 and second connecting structures on the axial end surface of the side wall forming frame 120. Therefore, when separating the circular hole forming frame 110 from the side wall forming frame 120, all unlocking push rods need to be triggered simultaneously to avoid accidental operation.

[0036] It is understood that the side wall forming frame 120 may also be a split structure. For example, the side wall forming frame 120 may be composed of multiple side wall forming sub-frames. A third connecting structure and a fourth connecting structure are provided at the edges of the side wall forming sub-frames. The third connecting structure and the fourth connecting structure can be used to sequentially connect the multiple side wall forming sub-frames to form the side wall forming frame 120. The third connecting structure may be the same as the first connecting structure, and the fourth connecting structure may be the same as the second connecting structure.

[0037] Reference Figure 1It can be understood that the cavity 130 formed in the mold body matches the shape of the cylinder body. Therefore, the internal cavities of the two circular hole forming frames 110 can be different, and the internal cavities of the side wall forming frame 120 at both ends of the axial direction can also be different. When the circular hole forming frame 110 and the side wall forming frame 120 are assembled, the continuity of the internal space of the frame must be ensured, that is, after the circular hole forming frame 110 and the side wall forming frame 120 are assembled, the side wall of the internal cavity formed is smooth.

[0038] Reference Figure 2 , Figure 2 This is a cross-sectional schematic diagram from another perspective of the combination of the mold body and the sand core liner 200 in the cylinder sand core manufacturing mold provided by the embodiment of the present application. It can be understood that the cross-sectional shape of the cylinder body in different directions is different, and accordingly, the internal cavity of the circular hole forming frame 110 and the internal cavity of the side wall forming frame 120 at both ends of the axial direction are also adjusted accordingly. Figure 1 As shown in the cross section of the inner cavity of the side wall forming frame 120 at both ends of the axial direction in the first direction, it can be seen that the cross section of the main part of the cylinder body in the first direction is a rectangle with rounded corners, while Figure 2 As shown, from the cross-section of the internal cavity at both axial ends of the side wall forming frame 120 in the second direction, it can be seen that the cross-section of the main part of the cylinder body in the first direction is a trapezoid with smooth corners.

[0039] It is understood that a piston module is integrated into the inner wall of the circular hole forming frame 110. The piston module can be connected to the control system through an external hydraulic pipe. By driving the piston module, the sand mold filler filled in the circular hole forming frame 110 can be squeezed and pushed toward the side wall forming frame 120, while compensating the sand mold filler. A first bolt is provided on the edge of the side wall forming frame 120. Specifically, bolt grooves are provided at the four corners of the outer wall of the frame. The bolt head is embedded in the bolt groove. The end of the screw abuts against the inner wall of the side wall forming frame 120. The pressure applied by the end of the screw to the inner wall of the side wall forming frame 120 can be adjusted by the bolt head, thereby adjusting the pressure of the inner wall of the side wall forming frame 120 on the sand mold filler. The first bolts in different positions can achieve pressure adjustment at local positions, which helps to ensure the consistency of the size of the cylinder sand core. It is worth noting that pressure sensors can also be integrated into the inner walls of the circular hole forming frame 110 and the side wall forming frame 120 to detect the pressure in the cavity 130, that is, the pressure of the sand mold filler.

[0040] It is understood that the sand core liner 200 is used to be placed in the mold cavity 130, and the gap between the sand core liner 200 and the mold body is used to fill the sand mold filler, thereby reducing the amount of sand required when making the cylinder sand core and reducing the weight of the cylinder sand core. In order to ensure the production quality of the cylinder sand core in the circular hole area, an annular slot is provided on the axial end face of the sand core liner 200. The annular slot can be used to install the end face protection cover 210. The end face protection cover 210 is tightly matched with the axial end face of the sand core liner 200 through the annular slot. The guard plate of the end face protection cover 210 extends outward. When the sand core liner 200 and the circular hole forming frame 110 are assembled, the guard plate contacts the inner wall of the frame, ensuring that the gap between the sand core liner 200 and the circular hole forming frame 110 is constant. It can effectively avoid the sand core liner 200 from vibrating or pressure-induced deviation during the sand shooting process, resulting in uneven sand layer thickness, and help to ensure that the sand coating thickness of the circular hole areas at both ends is accurately controlled.

[0041] It can be understood that the sand core inner liner 200 is hollow, and the side wall of the sand core inner liner 200 is provided with a plurality of exhaust holes 214 that pass through the side wall, wherein the guard plate can cover the axial end face of the sand core inner liner 200 and the entrance of the hollow cavity to prevent the sand mold filler from entering the interior of the sand core inner liner 200, and a ventilation hole can be provided at the edge of the guard plate, and the ventilation hole can be connected to the hollow cavity of the sand core inner liner 200, and combined with the exhaust hole 214 to form an external exhaust channel. Therefore, after sand shooting, the sand mold filler covering the outer wall of the sand core inner liner 200 can be exhausted through the external exhaust channel.

[0042] It is understood that a first cooling duct surrounding the internal cavity of the sidewall forming frame 120 can be embedded in the sidewall forming frame 120. Similarly, a first cooling duct surrounding the internal cavity of the circular hole forming frame 110 can also be embedded in the circular hole forming frame 110. The cooling ducts of different frames are not interconnected. After the mold cavity 130 is filled with the sand filling material, coolant can be injected into the first cooling duct. The circulating coolant accelerates the solidification of the cylinder sand core and reduces the risk of deformation of the cylinder sand core.

[0043] It is understandable that a second cooling pipe is also provided on the inner wall of the sand core liner 200. After the sand mold filler is filled in the mold cavity 130, coolant can also be injected into the second cooling pipe. The circulating coolant accelerates the solidification of the cylinder sand core and reduces the risk of deformation of the cylinder sand core.

[0044] It is worth noting that a plurality of reinforcing ribs are provided inside the sand core liner 200. The reinforcing ribs extend axially from one axial end face of the sand core liner 200 to the other axial end face. By arranging the reinforcing ribs, the structural rigidity of the sand core liner 200 can be strengthened, the pressure bearing capacity of the sand core liner 200 can be increased, and the quality of the cylinder sand core affected by the deformation of the sand core liner 200 can be reduced. Among them, a cross-shaped solid frame can also be provided in the hollow cavity of the sand core liner 200, and radial reinforcing ribs can be added in the circular hole areas at both ends. The radial reinforcing ribs can abut against the inner wall of the sand core liner 200, thereby enhancing the bearing capacity of the sand core liner 200 in the circular hole area and avoiding deformation of the sand core liner 200 in the circular hole area. In addition, the second cooling pipe can be fixed on the side wall of the axially arranged reinforcing ribs inside the sand core liner 200, and the reinforcing ribs can be cooled synchronously by the second cooling pipe to reduce the risk of thermal stress cracks in the reinforcing ribs.

[0045] It should be noted that the cross-shaped solid frame can be divided into multiple sections, with the joints between adjacent sections designed as tenons and mortises, secured with screws. Magnet structures can be embedded at both ends of the cross-shaped solid frame. This magnetic attraction allows the cross-shaped solid frame to be quickly separated from the hollow cavity of the sand core liner 200, facilitating separation of the sand core liner 200 from the cylinder sand core. Furthermore, the detachable cross-shaped solid frame can promptly replenish the pressure-bearing capacity of the sand core liner 200, reducing the loss rate of the sand core liner 200.

[0046] It can be understood that the sand core liner 200 can be a split structure. Specifically, the sand core liner 200 can include a middle core bone and two head core bones. The middle core bone corresponds to the position of the side wall forming frame 120, and the two head core bones correspond to the positions of the two circular hole forming frames 110 respectively. The two ends of the middle core bone can be fixed to the corresponding head core bones by bolts, thereby forming the sand core liner 200. The two head core bones are also provided with a magnetic structure. After the cylinder body sand core is demoulded, the magnetic structure of the head core bone can be adsorbed by the magnetic device, and then the cylinder body sand core can be knocked to quickly separate the cylinder body sand core and the sand core liner 200. In addition, the magnetic structure of the head core bone also helps to magnetically fix the sand core liner 200 on the molding platform, thereby improving the stability of the sand core liner 200 during sand core production.

[0047] It is understood that a plurality of sand-hanging portions are provided on the outer wall of the sand core liner 200. The sand-hanging portions can increase the stability of the sand mold filler adhering to the sand core liner 200, reduce the probability of the sand layer falling off the sand core liner 200, and avoid affecting the quality of the cylinder sand core due to sand falling. Specifically, the sand-hanging portion includes a sand-hanging groove 211 and a sand-hanging protrusion. The sand-hanging groove 211 can be a serrated groove provided on the outer wall of the sand core liner 200, while the sand-hanging protrusion can be a square block structure or a round rod structure. The outer surface of the sand-hanging protrusion can be smooth or have a threaded structure. By providing a plurality of sand-hanging grooves 211 and sand-hanging protrusions on the outer wall of the sand core liner 200, the roughness of the outer wall of the sand core liner 200 is changed to improve the adhesion of the sand mold filler.

[0048] Reference Figure 3 , Figure 3 : It is a top view of the combination of the mold body and the sand core liner 200 in the cylinder sand core manufacturing mold provided by the embodiment of the present application. It is worth noting that the sand hanging protrusions provided in the outer wall area of ​​the sand core liner 200 corresponding to the circular hole forming frame 110, that is, the head section core bone, include protrusions with different protrusion heights. Specifically, the sand hanging protrusions include a first protrusion 212 and a second protrusion 213. The height of the first protrusion 212 protruding outward is greater than the height of the second protrusion 213 protruding outward, thereby facilitating the fixing of different resin sand layers. Among them, the first protrusion 212 and the second protrusion 213 can be staggered on the outer wall of the sand core liner 200 to form a high-low-high wavy surface.

[0049] When making a cylinder block sand core, different sand layers are formed between the mold cavity 130 corresponding to the circular hole area and the sand core inner shell 200 by filling different sand mold fillers. Specifically, a first sand mold filler can be filled near the sand core inner shell 200 to form an inner sand layer, i.e., the first sand mold filler. The first sand mold filler can be a highly permeable resin sand, such as furan resin sand, and a second sand mold filler can be filled near the circular hole forming frame 110 to form an outer sand layer, i.e., the second sand layer. The second sand mold filler can be a sintering-resistant material, such as a mixture of zircon sand and nano-graphite powder to form a zirconium-based sintering-resistant coating; at this time, the first protrusion 212 corresponds to the corresponding area of ​​the second sand layer, providing strong anchoring for the second sand layer to resist the erosion of high-temperature molten iron, and the second protrusion 213 is located in the corresponding area of ​​the first sand layer, enhancing the initial bonding force of the sand layer and avoiding the slippage of sand grains during the sand shooting process. The sand layer is fixed in layers by protrusions of different heights, which are adapted to sand mold fillers with different properties. The differentiated distribution of high and low protrusions can effectively compensate for the thermal expansion difference between the sand layer and the sand core liner 200.

[0050] In the second aspect, the embodiment of the present application provides a method for manufacturing a cylinder sand core, which is applied to the cylinder sand core manufacturing mold provided in the embodiment of the first aspect above, with reference to Figure 4 , Figure 4 210 is a process diagram of a cylinder sand core manufacturing method provided by an embodiment of the present application, and the method specifically comprises: first, installing the end face protection cover 210 on the annular slot at one end of the sand core inner liner 200, that is, placing the end on which the end face protection cover 210 is installed on the molding platform, wherein, when the head section core bone of the sand core inner liner 200 is provided with a magnetic structure, the magnetic structure can be used to magnetically fix the sand core inner liner 200 on the molding platform, and then, one of the circular hole forming frames 110 is mounted on the bottom of the sand core inner liner 200, and the internal cavity of the circular hole area of ​​the circular hole forming frame 110 is abutted and fixed with the end face protection cover 210, thereby fixing the sand core inner liner 200 and the circular hole forming frame 110 through the end face protection cover 210. distance; then, the side wall forming frame 120 is connected to the circular hole forming frame 110 at the bottom through the first connecting structure and the second connecting structure, and it is determined whether the distance between the side wall forming frame 120 and the sand core liner 200 meets the requirements. If the distance meets the requirements, the other circular hole forming frame 110 is connected to the side wall forming frame 120 to form the sleeve frame body; the first sand mold filler is filled in the gap between the outer wall of the sand core liner 200 and the inner wall of the cavity 130, and the piston module is started to compensate for the sand core shrinkage, and the first bolt is adjusted to adjust the local pressure until the thickness of the first sand mold filler meets the standard and is completely filled in the cavity 130, and then the other end face protection cover 210 is installed on the annular slot.

[0051] After filling the first sand mold filler and installing the end face protection cover 210, cooling water can be injected into the first cooling pipe and the second cooling pipe respectively for circulation cooling to reduce the sand core temperature and complete the cooling of the sand layer. Then, the first connecting structure and the second connecting structure are unlocked, and the cylinder sand core is separated from the circular hole forming frame 110 and the side wall forming frame 120 to facilitate the subsequent curing process. It should be noted that the cylinder sand core can refer to the sand core liner with the sand mold filler attached.

[0052] It is understandable that the method can also adopt a multi-layer sand coating method to make the cylinder sand core. Specifically, the end face protection cover 210 is first installed on the annular slot at one end of the sand core inner liner 200, that is, the end with the end face protection cover 210 installed is placed on the molding platform. In which, when the head section core bone of the sand core inner liner 200 is provided with a magnetic structure, the magnetic structure can be used to magnetically fix the sand core inner liner 200 on the molding platform. Then, one of the circular hole forming frames 110 is mounted on the bottom of the sand core inner liner 200, and the internal cavity of the circular hole area of ​​the circular hole forming frame 110 is abutted and fixed with the end face protection cover 210, thereby fixing the distance between the sand core inner liner 200 and the circular hole forming frame 110 through the end face protection cover 210. , then a sand layer baffle is placed between the sand core liner 200 and the circular hole forming frame 110, wherein a through hole is opened on the sand layer baffle that corresponds to the first protrusion 212 on the side wall of the sand core liner 200, and the through hole passes through the first protrusion 212 and can be fixed between the sand core liner 200 and the circular hole forming frame 110, and then a first sand mold filler is used to fill between the outer wall of the sand core liner 200 and the sand layer baffle, so that the first sand mold filler is filled to the top of the second protrusion 213 (for example, a thickness of 10 mm), forming an inner second sand layer, and then a second sand mold filler is used to fill between the sand layer baffle and the inner wall of the circular hole forming frame 110, so that the second sand mold filler is filled to the top of the first protrusion 212 (for example, a thickness of 10 mm). The thickness is 10mm), forming the first sand layer of the outer layer; after completing the multi-layer sand covering of a circular hole area, the sand layer baffle is taken out, and the side wall forming frame 120 is connected to the circular hole forming frame 110 at the bottom through the first connecting structure and the second connecting structure, and it is determined whether the distance between the side wall forming frame 120 and the sand core liner 200 meets the requirements. If the distance meets the requirements, the first sand mold filler is used to fill the space between the side wall forming frame 120 and the outer wall of the sand core liner 200; after completing the sand shooting process of the main area of ​​the cylinder body, continue to connect another circular hole forming frame 110 to the side wall forming frame 120 to form a sleeve frame body, and place the sand layer baffle between the circular hole forming frame 110 and the sand core liner that have not yet been filled with sand. 200, similarly, the first sand mold filler is used to fill between the outer wall of the sand core inner liner 200 and the sand layer baffle, so that the first sand mold filler is filled to the top of the second protrusion 213 to form the second inner sand layer, and then, the second sand mold filler is used to fill between the sand layer baffle and the inner wall of the circular hole forming frame 110, so that the second sand mold filler is filled to the top of the first protrusion 212 to form the first outer sand layer, completing the multi-layer sand covering of the other circular hole area; remove the sand layer baffle, and start the piston module to compensate for the sand core shrinkage, and adjust the first bolt to adjust the local pressure until the thickness of the first sand mold filler meets the standard and is completely filled in the mold cavity 130, and then install the other end face protection cover 210 on the annular slot.

[0053] In summary, the embodiments of the present application can realize the following application scenarios: when making sand cores for the cylinder block of a marine diesel engine, the module body 100 and the sand core liner 200 can be combined to fill the cavity 130 corresponding to the circular hole area with multiple layers of different sand mold fillers to improve the thermal conductivity and sintering resistance of the cylinder sand core corresponding to the circular hole area, and the cavity 130 corresponding to the cylinder body area can be filled with a single sand mold filler or multiple layers of different sand mold fillers. After filling the sand mold filler, the piston module is used to compensate for the shrinkage of the sand core, and the first bolt is adjusted to adjust the local pressure. The end face protection covers 210 at both ends of the sand core liner 200 are used to maintain a constant distance between the sand core liner 200 and the mold body and provide a rigid boundary for the sand layer on the surface of the circular hole area, thereby reducing the deformation of the cylinder sand core in the circular hole area; after the sand core filler cools, the module body 100 can be removed from the cylinder sand core in blocks by unlocking the first connecting structure and the second connecting structure to complete the demolding of the cylinder sand core.

[0054] The embodiments of the present application are described in detail above in conjunction with the accompanying drawings, but the present application is not limited to the above embodiments. Various changes can be made within the scope of knowledge possessed by ordinary technicians in the technical field without departing from the purpose of the present application.

Claims

1. A cylinder sand core production mold, characterized in that: include: A mold body, comprising a sidewall forming frame and two circular hole forming frames, each of the circular hole forming frames being provided with a first connecting structure at the bottom, an axial end surface of the sidewall forming frame being provided with a second connecting structure for detachably connecting to the first connecting structure, an internal cavity of the sidewall forming frame and the internal cavities of all the circular hole forming frames being combined to form a mold cavity that matches the shape of the cylinder body cavity, an inner wall of the circular hole forming frame being provided with a piston module for compensating for shrinkage deformation of the sand core, and an edge of the sidewall forming frame being provided with a first bolt for adjusting the pressure on the sand core; A sand core liner is located in the mold cavity, and an annular slot for installing an end face protection cover is provided on the axial end face of the sand core liner. The end face protection cover includes an annular mounting plate matching the annular slot, and one end of the annular mounting plate extends radially outward to form a protective plate matching the circular hole shape of the circular hole forming frame.

2. The cylinder block sand core production mold according to claim 1, characterized in that: The side wall forming frame and the circular hole forming frame are respectively embedded with a first cooling pipe surrounding the internal cavity.

3. The cylinder sand core production mold according to claim 1, characterized in that: The outer side wall of the sand core inner container is provided with a plurality of sand hanging parts, and the sand hanging parts include sand hanging grooves and sand hanging protrusions.

4. The cylinder block sand core production mold according to claim 3, characterized in that: The sand hanging protrusion located in the outer side wall area corresponding to the circular hole forming frame includes a first protrusion and a second protrusion. The outward protrusion height of the first protrusion is greater than the outward protrusion height of the second protrusion, so as to fix different resin sand layers.

5. The cylinder sand core production mold according to claim 1, characterized in that: The sand core inner container is hollow, and a plurality of exhaust holes penetrating the side wall of the sand core inner container are opened.

6. The cylinder sand core production mold according to claim 5, characterized in that: A plurality of reinforcing ribs are axially arranged on the inner wall of the sand core liner, and the reinforcing ribs extend from one axial end face of the sand core liner to the other axial end face.

7. The cylinder sand core production mold according to claim 6, characterized in that: The inner wall of the sand core liner is provided with a second cooling pipe, and the second cooling pipe is fixed on the side wall of the reinforcing rib.

8. The cylinder sand core production mold according to claim 1, characterized in that: The sand core liner includes a middle core bone corresponding to the position of the side wall forming frame, and a head core bone corresponding to the position of the circular hole forming frame. The head core bone is fixed to the two ends of the middle core bone by bolts, and the head core bone is provided with a magnetic structure for disassembling the sand core liner.

9. A method for manufacturing a cylinder sand core, characterized in that: Applicable to the cylinder block sand core manufacturing mold according to any one of claims 1 to 8, the method comprises: installing the end face protection cover on the annular slot at one end of the sand core inner shell, sleeve one of the circular hole forming frames on one end of the sand core inner shell, so as to fix the distance between the sand core inner shell and the circular hole forming frame through the end face protection cover; connecting the side wall forming frame and the other circular hole forming frame to the circular hole forming frame in sequence through the first connecting structure and the second connecting structure; using the first sand mold filler to fill the space between the outer wall of the sand core inner shell and the inner wall of the mold cavity, starting the piston module and adjusting the first bolt, and then installing the other end face protection cover on the annular slot.

10. The method for manufacturing a cylinder sand core according to claim 9, wherein: The method further comprises: installing the end face protection cover on the annular slot at one end of the sand core inner shell, sleeve one of the circular hole forming frames on one end of the sand core inner shell, so as to fix the distance between the sand core inner shell and the circular hole forming frame through the end face protection cover; placing a sand layer baffle between the sand core inner shell and the circular hole forming frame, using a first sand mold filler to fill between the outer wall of the sand core inner shell and the sand layer baffle, and then using a second sand mold filler to fill between the sand layer baffle and the inner wall of the circular hole forming frame; removing the sand layer baffle, and connecting the sand layer baffle to the inner wall of the circular hole forming frame through the first connecting structure and the second connecting structure. The side wall forming frame and the other circular hole forming frame are connected to the circular hole forming frame in sequence; the first sand mold filler is used to fill the space between the side wall forming frame and the outer wall of the sand core inner liner, the sand layer baffle is placed between the circular hole forming frame and the sand core inner liner that have not been filled with sand, the first sand mold filler is used to fill the space between the outer wall of the sand core inner liner and the sand layer baffle, and then the second sand mold filler is used to fill the space between the sand layer baffle and the inner wall of the circular hole forming frame; the sand layer baffle is taken out, the piston module is started and the first bolt is adjusted, and then the other end face protection cover is installed on the annular slot.

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