Simplified multi-stage parting casting process for pump valve type castings

Abstract

The application discloses a kind of multistage parting casting processes of simplifying pump valve castings, it is related to casting process technical field, including determining the parting process of casting, and making lower mould box;Design and make intermediate body shell core;According to the runner of casting design and make runner core;According to intermediate body shell core making upper mould box;Put runner core to the predetermined position in lower mould box, then intermediate body shell core is sequentially assembled and put to the predetermined position in lower mould cavity;Upper mould box is butt-jointed with lower mould box and is fixed, then metal liquid is poured into mould cavity, after cooling, the formed casting is taken out;Casting is cooled to normal temperature, then sand cleaning shot blasting and go seam polishing finish processing;The application designs and makes corresponding intermediate body shell core for each multistage parting surface of casting, and the structure at multistage parting surface is formed by intermediate body shell core, so that the multistage parting of casting is simplified to one level parting, realizes the simplification of complex casting casting, and it is convenient to complete production task with high efficiency in automatic production line.

Description

Technical Field

[0001] This invention relates to the field of casting technology, and in particular to a simplified multi-stage parting casting process for pump and valve castings. Background Technology

[0002] Pumps and valves are widely used in industries such as petroleum, wastewater treatment, automobiles, ships, and gas, resulting in a huge demand for castings both domestically and internationally.

[0003] Many pump and valve products have relatively complex structures, and the commonly used process of single-stage parting, which involves dividing the mold into a base box and a cover box, cannot achieve the desired casting effect. The current common method is two-stage parting, also known in casting as three-stage mold making. This involves stacking three mold boxes to complete the molding process; this is called two-stage parting. More complex processes using four or more stacked mold boxes are called multi-stage parting processes.

[0004] Because the original two- or multi-stage parting casting process is not suitable for mechanized production lines, most casting operations are done manually. This results in casting companies' production capacity being unable to meet the needs of customers' large-volume purchases. More importantly, the multi-stage parting casting process in the original casting process, which uses multiple stacked sand boxes, significantly reduces the precision and appearance of the castings. At the same time, the casting process is cumbersome and complex, resulting in low labor productivity, high production costs, and unstable overall yield rates for manually produced products. Furthermore, fluctuations in product dimensional accuracy can easily lead to batch processing rejections and other problems. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a simplified multi-stage parting casting process for pump and valve castings.

[0006] To solve the above technical problems, the technical solution of the present invention is as follows:

[0007] A simplified multi-stage parting casting process for pump and valve castings, characterized by: including:

[0008] Determine the parting process for the casting and fabricate the lower mold box for the casting. The parting process includes single-stage parting and multi-stage parting of the casting.

[0009] For each multi-level parting design, an intermediate shell core mold is designed and manufactured, and an intermediate shell core is manufactured through the intermediate shell core mold. The lower shape of the intermediate shell core matches the upper shape of the casting at the corresponding multi-level parting point, and the upper shape of the intermediate shell core matches the shape of the casting that cannot be formed at the previous multi-level parting point.

[0010] Based on the flow channel design of the casting, the flow channel core box is made, and the flow channel core is made through the flow channel core box;

[0011] Based on the intermediate shell core, an upper mold box corresponding to the lower mold box is made;

[0012] Place the flow channel core into the predetermined position in the lower mold box, and then assemble the intermediate shell core in sequence and place it into the predetermined position in the lower mold cavity;

[0013] Connect and fix the upper mold box to the lower mold box, then pour the molten metal into the mold cavity, and remove the formed casting after cooling for 60-90 minutes.

[0014] The casting is cooled to room temperature, and then subjected to sand removal, shot blasting, and finishing polishing to remove seams.

[0015] As a preferred embodiment of the present invention for simplifying the multi-stage parting casting process of pump and valve castings, the upper mold box includes an upper mold plate and a matching sand box, the lower mold box includes a lower mold plate and a matching sand box, the upper mold plate and / or the lower mold plate are provided with feeding risers, and the intermediate shell core is provided with a feeding process platform that matches the feeding risers.

[0016] As a preferred embodiment of the present invention for simplifying the multi-stage parting casting process of pump and valve castings, wherein: positioning blocks are provided on the upper mold plate and / or the lower mold plate, and positioning grooves are correspondingly opened on the intermediate shell core for the positioning blocks to extend into.

[0017] As a preferred embodiment of the present invention for simplifying the multi-stage parting casting process of pump and valve castings, the present invention includes three positioning blocks that form a triangle.

[0018] As a preferred embodiment of the simplified multi-stage parting casting process for pump and valve castings according to the present invention, the process includes: designing and fabricating an intermediate shell core for each multi-stage parting step, comprising:

[0019] For each multi-level parting design, there is an intermediate shell core;

[0020] Design and manufacture the corresponding intermediate shell core box based on the intermediate shell core design;

[0021] Intermediate shell cores are made by using intermediate shell core boxes.

[0022] As a preferred embodiment of the simplified multi-stage parting casting process for pump and valve castings according to the present invention, the process includes: designing and fabricating a flow channel core box based on the flow channel of the casting, and fabricating the flow channel core using the flow channel core box, comprising:

[0023] The flow channel core box is designed according to the flow channel of the casting;

[0024] The flow channel core is made according to the flow channel core box.

[0025] As a preferred embodiment of the simplified multi-stage parting casting process for pump and valve castings in this invention, the thickness of the intermediate shell core is 12-15mm.

[0026] The beneficial effects of this invention are:

[0027] (1) The present invention designs and manufactures corresponding intermediate shell cores for each multi-level parting surface of the casting, and completes the formation of the structure at the multi-level parting surface through the intermediate shell cores, thereby simplifying the multi-level parting of the casting to a single-level parting, realizing the simplification of casting of complex castings, and facilitating the efficient completion of production tasks on automated production lines.

[0028] (2) The present invention provides positioning blocks on the upper mold plate and / or the lower mold plate, and corresponding positioning grooves are opened on the intermediate shell core for the positioning blocks to extend into. Through the cooperation of the positioning blocks and the positioning grooves, the positional stability of the intermediate shell core is ensured, thereby ensuring the accuracy of the casting shape.

[0029] (3) The present invention provides feeding risers on the upper mold plate and / or the lower mold plate, and correspondingly provides a feeding process platform on the intermediate shell core, thereby ensuring that the casting mold has feeding performance. Attached Figure Description

[0030] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0031] Figure 1 A schematic diagram illustrating the simplified multi-stage parting casting process for pump and valve castings provided by this invention;

[0032] Figure 2 This is a schematic diagram of the structure of the pump casting provided in this embodiment;

[0033] Figure 3 This is a schematic diagram of the two-stage parting line for the pump casting provided in this embodiment;

[0034] Figure 4 This is a schematic diagram of the lower mold plate of a simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0035] Figure 5 This is a schematic diagram of the structure of the first moving mold in the simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0036] Figure 6 This is a schematic diagram of the structure of the first fixed mold in the simplified multi-stage parting mold for pump and valve castings provided in this embodiment.

[0037] Figure 7 A schematic diagram of the intermediate shell core in a simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0038] Figure 8 This is a schematic diagram of the upper mold plate in a simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0039] Figure 9 The side view of the upper mold plate in the simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0040] Figure 10 This is a schematic diagram of the structure of the second moving mold in the simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0041] Figure 11 This is a schematic diagram of the structure of the second fixed mold in the simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0042] Figure 12 This is a schematic diagram of the flow channel core in a simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0043] Figure 13 A three-dimensional schematic diagram of the flow channel core in a simplified multi-stage parting mold for pump and valve castings provided in this embodiment;

[0044] The components are: 1. Upper mold plate; 2. Lower mold plate; 3. Feeding riser; 4. Positioning block; 5. Intermediate shell core; 6. Positioning groove; 7. Feeding process platform; 8. First moving mold; 9. First fixed mold; 10. Second moving mold; 11. Second fixed mold; 12. Runner core. Implementation

[0045] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0046] Figure 1 This is a schematic flowchart illustrating a simplified multi-stage parting casting process for pump and valve castings provided in this embodiment of the application. The casting process includes steps S101-S107, and the specific steps are explained below:

[0047] Step S101: Determine the parting process of the casting and make the lower mold box of the casting. The parting process includes single-stage parting and multi-stage parting.

[0048] Specifically, for castings, the general process parting starts from the center of the pump body's flow channel as the first-level parting, forming the part below and above the flow channel. If the external shape of either part can be completely formed using a mold, then only a first-level parting is needed. If either part has a structure that cannot be directly formed by the mold, then a second-level parting is required to fully cast the part. If the second-level parting still leaves unformable structures, then a third-level parting is designed for that structure, and so on.

[0049] It is understandable that two-level parting, three-level parting and above all belong to multi-level parting processes.

[0050] See Figure 2 In this embodiment, taking foreign pump castings as an example, the horizontal plane of the maximum outer diameter of the pump body flow channel is determined as the first-level parting surface, thus forming the part below the pump body flow channel and the part above the pump body flow channel. Analyzing these two parts, the external shape of the part below the first-level parting surface can be completely made into the lower mold plate 2, while the part above the first-level parting surface, this part of the product structure has an upper flange part at the reinforcing rib at the lower opening of the upper flange that cannot be directly brought out as a whole casting part. Figure 3 This is a schematic diagram of the two-stage parting line for the casting.

[0051] After determining the parting surface of the casting, the lower mold box is designed and fabricated. The lower mold box includes the lower mold plate 2 and its matching sand box. The specific fabrication process is as follows: wet molding sand is filled and compacted within the fabricated lower mold plate 2 and the matching sand box using vibration. Then, the mold plate is removed, forming the lower mold box with the matching sand box and wet molding sand as the carrier. See the image for the fabricated lower mold plate 2. Figure 4 .

[0052] Step S102: Design and manufacture an intermediate shell core 5 mold for each multi-level parting line, and manufacture the intermediate shell core 5 using the intermediate shell core 5 mold. The lower shape of the intermediate shell core 5 matches the upper shape of the casting at the corresponding multi-level parting line, and the upper shape of the intermediate shell core 5 matches the shape of the casting that cannot be formed at the previous multi-level parting line.

[0053] Specifically, for multi-stage parting of castings, an intermediate shell core 5 mold is designed and manufactured, and then the intermediate shell core 5 is manufactured.

[0054] For castings that originally required two-stage parting, the lower shape of the intermediate shell core 5 perfectly matches the upper shape of the casting, and the upper shape of the intermediate shell core 5 perfectly matches the shape of the upper part of the casting that cannot be produced using a single-stage parting. This intermediate shell core 5 achieves the design goal of simplifying two-stage parting into a single-stage parting. For castings that originally required three-stage or higher parting, a corresponding intermediate shell core 5 mold is designed and manufactured for each multi-stage parting surface, and then the corresponding intermediate shell core 5 is produced. The intermediate shell cores 5 are then assembled to achieve the goal of simplifying multi-stage parting into a single-stage parting.

[0055] The specific steps for this process are explained below:

[0056] a. Design the corresponding intermediate shell core 5 for each multi-level parting surface.

[0057] b. Design and manufacture the corresponding intermediate shell core 5 core box based on the intermediate shell core 5.

[0058] c. The intermediate shell core 5 is made by using the intermediate shell core 5 core box.

[0059] Taking the aforementioned foreign pump castings as an example, the intermediate shell core 5 core box, which is matched with the designed intermediate shell core 5, is divided into a first moving mold 8 and a first fixed mold 9; wherein, the first moving mold 8 is as follows Figure 5 As shown, the first fixed mold 9 is as follows Figure 6 As shown, the manufactured intermediate shell core 5 is as follows Figure 7 As shown.

[0060] It should be noted that the external shape and internal cavity shape of the intermediate shell core 5 generally adopt a conformal design, which reduces casting costs. To facilitate mold removal during the casting molding process, the external shape of the intermediate shell core 5 can also be locally adjusted. The thickness of the intermediate shell core 5 is generally designed to be 12-15mm. The design principle here is to ensure that the strength of the intermediate shell core 5 meets the filling requirements during molten metal filling and to prevent thermal deformation during filling.

[0061] Preferably, a positioning block 4 is provided on the upper mold plate 1 and / or the lower mold plate 2, and a positioning groove 6 is correspondingly provided on the intermediate shell core 5 for the positioning block 4 to extend into.

[0062] Taking the aforementioned foreign pump castings as an example, three positioning blocks 4 are provided on the lower mold plate 2, forming a triangle on the end face of the lower mold plate 2. Correspondingly, three positioning grooves 6 are provided at corresponding positions on the intermediate shell core 5. During installation, the positioning blocks 4 on the lower mold plate 2 can extend into the corresponding positioning grooves 6, ensuring the positional stability of the intermediate shell core 5 and thus guaranteeing the accuracy of the casting shape.

[0063] In addition, for gray cast iron or ductile iron castings, the shrinkage tendency is large, so process feeding needs to be considered in the mold design. For such castings, feeding risers 3 are provided on the upper mold plate 1 and / or the lower mold plate 2, and correspondingly, a feeding process platform 7 that cooperates with the feeding risers is provided on the intermediate shell core 5.

[0064] Taking the aforementioned foreign pump castings as an example, see... Figure 8 and Figure 9 A feeding riser 3 is provided on the upper mold plate 1. Correspondingly, a feeding process platform 7 is provided on the intermediate shell core 5, see [reference]. Figure 7 After assembly, the feeding riser 3 on the upper mold plate 1 can be matched with the corresponding feeding process platform 7 on the intermediate shell core 5.

[0065] Step S103: Design and fabricate the flow channel core 12 according to the flow channel of the casting.

[0066] Specifically, based on the inner cavity or flow channel of the casting, a matching flow channel core 12 core box is designed, and the flow channel core 12 is prefabricated before production for easy use during molding.

[0067] Taking the aforementioned foreign pump castings as an example, the core box of the flow channel core 12, which is matched with the designed flow channel core 12, is divided into a second moving mold 10 and a second fixed mold. The second moving mold 10 is as follows: Figure 10 As shown, the second fixed mold is as follows Figure 11 As shown, the fabricated flow channel core 12 is as follows Figure 12 As shown.

[0068] Step S104: Make an upper mold box corresponding to the lower mold box based on the intermediate shell core 5.

[0069] Specifically, based on the shape and size parameters of the intermediate shell core 5 and the lower mold plate 2, the corresponding upper mold plate 1 and matching sand box are designed.

[0070] It should be noted that the design of the upper mold plate 1 and the lower mold plate 2 takes into account the matching of the internal cavity with the intermediate shell core 5, while also considering the ease of molding and demolding, as well as the rationality of the casting gating and riser process system, so as to ensure that the casting does not have shrinkage cavities or porosity defects due to insufficient feeding.

[0071] Step S105: Place the flow channel core 12 into the predetermined position in the lower mold box, and then assemble the intermediate body shell core 5 in sequence and place it into the predetermined position in the lower mold cavity.

[0072] Specifically, first, the lower mold plate 2 is installed on the corresponding station of the molding machine on the production line. Then, the matching sand box is closed, the mold surface is cleaned, the mixed molding material is placed in, and it is vibrated and compacted. The mold is then formed by the matching sand box and molding material to create the lower mold box. After cleaning the lower mold box, the runner core 12 is placed in the predetermined position in the lower mold cavity, and then the pre-made intermediate shell core 5 is placed in the predetermined position in the lower mold cavity.

[0073] Step S106: Connect and fix the upper mold box to the lower mold box, then pour the molten metal into the mold cavity, and remove the formed casting after cooling for 60-90 minutes.

[0074] Specifically, the upper mold plate 1 is installed on the corresponding station of the molding machine on the production line. The matching sand box is closed, the mold surface is cleaned, the mixed molding material is placed in, and it is vibrated and compacted. After demolding, an upper mold box is formed by the sand box and molding material. Then, an exhaust channel is opened at the predetermined position on the upper cavity, and the sprue and riser and the loose sand in the upper cavity are cleaned. Then, the cleaned upper mold box is aligned with the lower mold box using positioning pins. After closing, the upper mold box and the lower mold box are fixed with box clips or fixing screws. Then, the molten metal is injected from the reserved gating system. After filling, it is cooled with the box for 60-90 minutes before being removed from the box.

[0075] Step S107: Cool the casting to room temperature, and then perform shot blasting, sand removal, and fine polishing to remove burrs.

[0076] Through the above process steps, the multi-level parting of castings is simplified to a single parting, which simplifies the casting of complex castings and makes it easier to complete production tasks efficiently on automated production lines.

[0077] This embodiment also provides a simplified casting mold for multi-stage parting of pump and valve castings, which includes a lower mold box, an upper mold box, an intermediate shell core 5, and a flow channel core 12.

[0078] Specifically, the lower mold plate 2 and its matching sand box are designed according to the shape and material requirements of the casting. Molding material is then added to the prepared lower mold plate 2 and matching sand box, vibrated, and compacted to form the lower mold box. The upper mold is designed based on the shape and dimensions of the lower mold plate 2 and the intermediate shell core 5. Upper mold plate 1 and its matching sand box are then made, and molding material is added to the upper mold plate 1 and matching sand box, vibrated, and compacted to form the upper mold box. The upper mold box and lower mold box are then joined to form a cavity.

[0079] An intermediate shell core 5 is designed and fabricated at each multi-stage parting point of the casting. See also Figure 7 The lower shape of each intermediate shell core 5 matches the upper shape of the casting at the corresponding multi-level parting surface, and its upper shape matches the shape of the casting that cannot be formed at the previous multi-level parting surface. The intermediate shell core 5 is located inside the mold cavity.

[0080] For castings that originally required two-stage parting, the lower shape of the intermediate shell core 5 perfectly matches the upper shape of the casting, and the upper shape of the intermediate shell core 5 perfectly matches the shape of the upper part of the casting that cannot be produced using a single-stage parting. This intermediate shell core 5 achieves the design goal of simplifying two-stage parting into a single-stage parting. For castings that originally required three-stage or higher parting, a corresponding intermediate shell core 5 mold is designed and manufactured for each parting surface, and then the corresponding intermediate shell core 5 is produced. The intermediate shell cores 5 are then assembled to simplify multi-stage parting into a single-stage parting.

[0081] The outer shape and inner cavity of the intermediate shell core should be designed in a conformal pattern as much as possible to save sand core costs. When designing the outer shape of the intermediate shell core, it is necessary to consider the ease of casting and demolding with the mold plate. The wall thickness of the intermediate shell core is generally 12-15mm, except for local shapes that need to be deliberately filled in for demolding.

[0082] The runner core 12 matches the shape of the runner within the casting. The runner core 12 is located within the cavity.

[0083] The aforementioned casting mold can simplify the multi-stage parting of castings into a single-stage parting, thereby simplifying the casting process of complex castings and facilitating the efficient completion of production tasks on automated production lines.

[0084] In addition to the above embodiments, the present invention may have other implementation methods; all technical solutions formed by equivalent substitution or equivalent transformation fall within the protection scope claimed by the present invention.

Claims

1. A multi-stage parting casting process for simplifying pump valve type castings, characterized by: The application relates to a casting method and a casting device. The application comprises the following steps: determining a parting process of a casting and making a lower flask of the casting, wherein the parting process comprises a primary parting and a multi-stage parting of the casting; designing and making an intermediate shell core mold for each multi-stage parting and making an intermediate shell core through the intermediate shell core mold, wherein a lower part of the intermediate shell core is matched with an upper part shape of the casting at a corresponding multi-stage parting, and an upper part of the intermediate shell core is matched with a shape of the casting which cannot be formed at a previous multi-stage parting; designing and making a runner core core box according to a runner of the casting, and making a runner core through the runner core core box; making an upper flask corresponding to the lower flask according to the intermediate shell core; placing the runner core into a predetermined position in the lower flask, and then placing the intermediate shell core into a predetermined position in the lower flask after being assembled in sequence; butting and fixing the upper flask and the lower flask, pouring metal liquid into a cavity, taking out a formed casting after cooling for 60-90 min; 2. The simplified pump valve type cast multi-stage parting casting process of claim 1, wherein: cooling the casting to normal temperature, and then carrying out sand cleaning, shot blasting, and polishing treatment.

3. The simplified pump valve type cast multi-stage parting casting process of claim 2, wherein: The upper flask comprises an upper flask mold and a matched sand box, the lower flask comprises a lower flask mold and a matched sand box, a feeding riser is arranged on the upper flask mold and / or the lower flask mold, and a feeding process platform matched with the feeding riser is arranged on the intermediate shell core.

4. The simplified pump valve type cast multi-stage parting casting process of claim 3, wherein: Positioning blocks are arranged on the upper flask mold and / or the lower flask mold, and positioning grooves for the positioning blocks to extend into are arranged on the intermediate shell core.

5. The simplified pump valve type cast multi-stage parting casting process of claim 1, wherein: The positioning blocks are arranged in three blocks, and the three blocks form a triangle. The method for designing and making an intermediate shell core mold for each multi-stage parting and making an intermediate shell core through the intermediate shell core mold comprises the following steps: designing a corresponding intermediate shell core for each multi-stage parting, designing and making a corresponding intermediate shell core core box according to the intermediate shell core; 6. The simplified pump valve type cast multi-stage parting casting process of claim 1, wherein: making an intermediate shell core through the intermediate shell core core box. The method for designing and making a runner core core box according to a runner of the casting and making a runner core through the runner core core box comprises the following steps: designing a runner core core box according to a runner of the casting; 7. The simplified pump valve type cast multi-stage parting casting process of claim 1, wherein: making a runner core according to the runner core core box. The thickness of the intermediate shell core is 12-15 mm.

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