Mold for casting butterfly valve housing

Abstract

The application discloses a butterfly valve shell casting mold, which comprises an inner surface forming mold and an outer surface forming mold. The inner surface forming mold comprises a sand core and an outer mold assembly. The outer mold assembly comprises a first mold shell and a second mold shell, which are sleeved on the outer side of the sand core. The sand core is provided with a plurality of support ribs. One end of the support rib is connected to the inner wall of the sand core, and the other end is connected to a center column. The outer surface forming mold comprises a sand box assembly and a forming assembly. The sand box assembly comprises an upper sand box and a lower sand box. The upper sand box can be inverted and stacked on the top of the lower sand box. The forming assembly comprises a base, a first forming piece and a semicircular arc-shaped second forming piece. The base is provided with a plurality of insertion slots, which are symmetrically arranged along the two sides of the first forming piece. The end of the second forming piece is provided with an insertion shaft, which is annularly provided with an elastic expansion sleeve. The insertion shaft is inserted into the insertion slot. The inner wall of the second forming piece and the outer wall of the first forming piece are mutually attached, and the connecting part is coated or coated with a filler.

Description

Technical Field

[0001] This invention relates to the field of butterfly valve casting equipment technology, and in particular to a mold for casting butterfly valve bodies. Background Technology

[0002] Reference Figure 1 This paper proposes a butterfly valve housing, which is a cylindrical structure with a flow channel for fluid passage, and its outer wall is connected with several side plates. The butterfly valve housing is formed by sand casting, typically using two sets of molds corresponding to its inner and outer surfaces to form a cavity. In related technologies, different sizes of valve housings require valve housings with different numbers of side plates, and different molds are needed during production. However, the cost of manufacturing multiple specifications of molds is very high, which does not meet production needs. Summary of the Invention

[0003] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a mold for casting butterfly valve bodies, which can disassemble and assemble the second forming part of the outer surface forming mold according to production needs, thereby adapting to the production needs of different valve bodies without the need to manufacture additional molds, greatly reducing production costs.

[0004] According to a first aspect of the present invention, a mold for casting a butterfly valve body is used to cast a valve body. The valve body is a cylindrical structure with a flow channel for fluid passage. Its outer wall is connected to several side plates. The mold includes an inner surface forming mold and an outer surface forming mold. The inner surface forming mold includes a sand core and an outer mold assembly. The outer mold assembly is a hexagonal vertical structure with cylindrical hollowed-out sections inside, including a first mold shell and a second mold shell. The first mold shell and the second mold shell are spliced ​​together and fitted onto the outside of the sand core. A sand injection gap is formed between the outer wall of the sand core and the inner wall of the outer mold assembly for sand injection. The sand core is a circular tube with a through channel. The channel is provided with multiple support ribs. One end of each support rib is connected to the inner wall of the sand core, and the other end is connected to a central column. The axis of the central column is collinear with the axis of the sand core. The multiple support ribs are arranged radially and uniformly from the central column outwards. The outer surface forming mold includes a sand box assembly and a forming assembly. The sand box assembly includes an upper sand box and a lower sand box. The upper sand box can be inverted and stacked on top of the lower sand box, and has a clearance in the middle. The sand core can be embedded in the clearance after sand injection. The forming assembly is used to press into the upper sand box and the lower sand box to form a forming groove. It includes a base, a first forming part, and a semi-circular arc-shaped second forming part. The first forming part is a semi-cylinder integrally formed with the base, located on the top surface of the base, and its arc surface faces upward. It is used for forming the cylindrical outer surface of the valve body. The base is provided with multiple slots. The multiple slots are symmetrically arranged along both sides of the first forming part. The end of the second forming part is provided with a shaft. The shaft is provided with an elastic tension sleeve. The shaft is inserted into the slot. The elastic tension sleeve is interference-fitted with the slot to fix the second forming part and the base. The inner wall of the second forming part is in close contact with the outer wall of the first forming part, and the connection is covered or coated with filler.

[0005] The mold for casting the butterfly valve body according to an embodiment of the present invention has at least the following beneficial effects: after the first mold shell and the second mold shell are spliced ​​and fixed, they are then fitted onto the outside of the sand core. Sand is then injected and compacted through the sand injection gap between the outer peripheral surface of the sand core and the inner surface of the outer mold assembly. The outer mold is then removed. The sand core after sand injection is then positioned and fitted with the forming mold of the outer surface of the butterfly valve to form a cavity. After the molten metal is injected and cast, the mold is demolded.

[0006] Fill the sand injection grooves of the upper and lower sand boxes with sufficient casting sand and flatten them. Then, invert the two molding components into the sand injection grooves and press them tightly. While compacting the casting sand, the first and second molding components extending from the base form corresponding molding grooves on the plane of the casting sand. These grooves then cooperate with the molding grooves of the inner surface molding mold to form the cavity for molding the valve body, making it convenient to use. The first molding component is a semi-cylindrical shape integrally formed with the base, mainly used to form the semi-cylindrical molding groove. The two molding components cooperate to form a cylindrical molding groove that matches the surface of the valve body cylinder. Furthermore, the second molding component extends from the first molding component to form a molding groove that matches the shape of the side plate. The lugs on the second molding component form molding grooves that match the shape of the lugs.

[0007] For valve body casting with different numbers of side plates, different production needs can be met by disassembling and assembling the second molded part, without the need to remanufacture a complete set of molds, which greatly saves production costs and is convenient to use, thus meeting production needs.

[0008] According to some embodiments of the present invention, the side wall of the insert shaft is provided with a fixing screw hole, and the elastic tension sleeve is provided with a corresponding fixing hole. A screw passes through the fixing hole, and the screw rotates toward the fixing screw hole to fix the elastic tension sleeve.

[0009] According to some embodiments of the present invention, the slot is detachably connected to a filler, the top surface of which is flush with the top surface of the base when inserted into the slot, and the gap between the filler and the base is also coated or covered with filler.

[0010] According to some embodiments of the present invention, the second molded part is connected to a lug molded part for lug casting of the valve body, and the lug molded part is integrally formed with the second molded part.

[0011] According to some embodiments of the present invention, a third molding is integrally formed on the side of the first molding part, the cross-section of the third molding part being trapezoidal for forming the shaft hole of the valve housing.

[0012] According to some embodiments of the present invention, the outer mold assembly is connected to a fixing plate, and the fixing plate is located at the connection position of the first mold shell and the second mold shell, for fixing the first mold shell and the second mold shell together.

[0013] According to some embodiments of the present invention, the fixing plate is provided with a plurality of first fixing holes, the first mold shell is provided with a second fixing hole, and the second mold shell is provided with a third fixing hole. The plurality of first fixing holes can simultaneously correspond to the second fixing hole and the third fixing hole, and the first mold shell and the second mold shell are respectively fixedly connected by fasteners.

[0014] According to some embodiments of the present invention, the central column is provided with a through hoisting hole for hoisting equipment to pass through and drive the sand core to move.

[0015] According to some embodiments of the present invention, the periphery of the base is provided with a positioning step, and when the first molded part and the second molded part are pressed down into the casting sand to a rated depth, the positioning step abuts against the top wall of the upper sand box or the lower sand box.

[0016] According to some embodiments of the present invention, four support ribs are provided, and the four support ribs are arranged at a 90° angle between each other.

[0017] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments, wherein:

[0019] Figure 1 This is a schematic diagram of the butterfly valve shell according to an embodiment of the present invention;

[0020] Figure 2 This is a schematic diagram of a mold for casting the valve body of a butterfly valve according to an embodiment of the present invention;

[0021] Figure 3 This is a partial schematic diagram of the molding assembly of the mold for casting the butterfly valve body according to an embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the inner surface forming mold of the butterfly valve shell casting mold according to an embodiment of the present invention;

[0023] Figure 5 This is an exploded view of the molding components of the mold for casting the butterfly valve body according to an embodiment of the present invention.

[0024] Figure 6 This is a partial cross-sectional schematic diagram of the insert shaft of the mold for casting the butterfly valve body according to an embodiment of the present invention.

[0025] Reference numerals: Valve housing 100; Flow channel 101; Side plate 110; Lug 111; Molding assembly 200; Base 210; First molding part 220; Second molding part 230; Insert shaft 231; Elastic tension sleeve 232; Fixing screw hole 233; Screw 234; Lug molding part 240; Third molding part 250; Positioning step 260; Sand box assembly 300; Upper sand box 310; Lower sand box 320; Butterfly valve inner surface molding mold 400; Sand injection gap 401; Outer mold assembly 410; First mold shell 411; Second mold shell 412; Fixing plate 413; Sand core 420; Channel 421; Support rib 430; Center column 440; Lifting hole 441. Detailed Implementation

[0026] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0027] In the description of this invention, it should be understood that the orientation descriptions, such as up, down, front, back, left, right, etc., are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting this invention.

[0028] In the description of this invention, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0029] In the description of this invention, unless otherwise explicitly defined, terms such as "set up," "install," and "connect" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this invention in conjunction with the specific content of the technical solution.

[0030] Reference Figure 1This paper proposes a butterfly valve housing 100, which is a cylindrical structure with a flow channel 101 for fluid passage, and its outer wall is connected with several side plates 110. The butterfly valve housing 100 is formed by sand casting, typically using two sets of molds corresponding to its inner and outer surfaces to form a cavity. In related technologies, different sizes of the valve housing 100 require valve housings 100 with different numbers of side plates 110, and different molds are needed during production. However, the cost of manufacturing multiple specifications of molds is very high, which does not meet production needs.

[0031] Therefore, referring to Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 This invention provides a casting mold for a butterfly valve housing 100, comprising an inner surface forming mold and an outer surface forming mold. The inner surface forming mold includes a sand core 420 and an outer mold assembly 410. The outer mold assembly 410 is a hexagonal vertical structure with cylindrical hollowed-out sections inside, including a first mold shell 411 and a second mold shell 412. The first mold shell 411 and the second mold shell 412 are spliced ​​together and fitted on the outside of the sand core 420. A sand injection gap 401 is formed between the outer wall of the sand core 420 and the inner wall of the outer mold assembly 410 for sand injection. The sand core 420 is a circular tube with a through channel 421. The channel 421 is provided with multiple support ribs 430. One end of the support rib 430 is connected to the inner wall of the sand core 420, and the other end is connected to a central column 440. The axis of the central column 440 is collinear with the axis of the sand core 420. The multiple support ribs 430 are arranged radially and uniformly from the central column 440 outwards. Understandably, after the first mold shell 411 and the second mold shell 412 are spliced ​​and fixed, they are then fitted onto the outside of the sand core 420. Sand is then injected and compacted through the sand injection gap 401 between the outer peripheral surface of the sand core 420 and the inner surface of the outer mold assembly 410. The outer mold is then removed, and the sand core 420 after sand injection is positioned and fitted with the forming mold on the outer surface of the butterfly valve to form a cavity. After the molten metal is injected and cast, the mold is demolded.

[0032] Furthermore, the sand core 420 is a cylindrical structure, not a solid cylinder, thus maximizing weight reduction. Supporting ribs 430 are provided within the channels 421 of the sand core 420 to provide some support and enhance the compressive and deformation resistance of the sand core 420's peripheral walls, ensuring that it will not deform during sand injection and pressing. The cylindrical shape of the sand core 420 also facilitates handling and transportation, enabling rapid demolding and release during repeated molding processes, thereby improving production efficiency.

[0033] Furthermore, referring to Figure 2 , Figure 3 , Figure 5 and Figure 6The outer surface molding mold includes a sand box assembly 300 and a molding assembly 200. The sand box assembly 300 includes an upper sand box 310 and a lower sand box 320. The upper sand box 310 can be inverted and stacked on top of the lower sand box 320, and has a clearance in the middle. The sand core 420 can be embedded in the clearance after sand injection. The molding assembly 200 is used to press into the upper sand box 310 and the lower sand box 320 to form a molding groove. It includes a base 210, a first molding part 220, and a semi-circular second molding part 230. The first molding part 220 is a semi-cylinder integrally formed with the base 210 and is located at the bottom. The top surface of the base 210, with its arc-shaped surface facing upward, is used for forming the outer cylindrical surface of the valve housing 100. The base 210 is provided with multiple slots, which are symmetrically arranged along both sides of the first molding part 220. The end of the second molding part 230 is provided with a shaft 231, and the shaft 231 is surrounded by an elastic tension sleeve 232. The shaft 231 is inserted into the slot, and the elastic tension sleeve 232 is interference-fitted with the slot to fix the second molding part 230 and the base 210. The inner wall of the second molding part 230 is in close contact with the outer wall of the first molding part 220, and the connection is covered or coated with filler. Sufficient casting sand is filled into the sand injection grooves of the upper sand box 310 and the lower sand box 320 and flattened. Then, the two molding components 200 are inverted in the sand injection grooves and pressed tightly. While compacting the casting sand, the first molding component 220 and the second molding component 230 extending from the base 210 form corresponding molding grooves on the plane of the casting sand. These grooves then cooperate with the molding grooves of the inner surface molding mold to form the cavity for molding the valve body 100, making it convenient to use. The first molding component 220 is a semi-cylindrical shape integrally formed with the base 210 and is mainly used to form a semi-cylindrical molding groove. The two molding components 200 cooperate to form a cylindrical molding groove that matches the cylindrical surface of the valve body 100. Furthermore, the second molding component 230 extends from the first molding component 220 and is used to form a molding groove that matches the shape of the side plate 110. The lug 111 on the second molding component 230 is used to form a molding groove that matches the shape of the lug 111.

[0034] For valve body 100 castings with different numbers of side plates 110, different production needs can be met by disassembling and assembling the second molding part 230, without the need to remanufacture a complete set of molds, which greatly saves production costs and is convenient to use, meeting production requirements. Furthermore, the second molding part 230 is directly interference-fitted into the slot through an elastic tension sleeve 232, which is convenient for disassembly and assembly and can further improve production efficiency. The interference-fit elastic tension sleeve 232 itself has a certain elastic force generated by resisting elastic deformation, which is converted into frictional force between the elastic tension sleeve 232 and the inner wall of the slot, thereby preventing the second molding part 230 from falling off when the molding assembly 200 is inverted and pressed down. The filler can fill and level the gaps between the first molding part 220, the second molding part 230 and the base 210, preventing the shape of the molding groove from being affected by the gaps after the non-integral molding assembly 200 is pressed down.

[0035] Reference Figure 5 and Figure 6 The side wall of the insert shaft 231 is provided with a fixing screw hole 233, and the elastic tension sleeve 232 is provided with a corresponding fixing hole. A screw 234 passes through the fixing hole, and the screw 234 rotates toward the fixing screw hole 233 to fix the elastic tension sleeve 232. It should be noted that repeated disassembly and assembly of the second molding component 230 will cause deformation and wear of the elastic tension sleeve 232, which will reduce the friction between the elastic tension sleeve 232 and the slot. When the molding assembly 200 is inverted, the second molding component 230 is prone to falling off. Fixing the elastic tension sleeve 232 with the screw 234 can effectively and periodically disassemble and replace the elastic tension sleeve 232, which is convenient.

[0036] Preferably, in some embodiments, the slot is detachably connected to a leveling member, the top surface of which is flush with the top surface of the base 210 when inserted into the slot. This detachable connection prevents the formation of additional forming grooves requiring secondary leveling when the forming assembly 200 is pressed down, thereby improving casting efficiency. Furthermore, the gap between the leveling member and the base 210 is also coated or covered with filler to prevent the forming assembly 200 from affecting the shape of the forming groove due to gaps after pressing down.

[0037] Reference Figure 3 and Figure 5 The second molding part 230 is connected to the lug 111 molding part, which is used for casting the lug 111 of the valve body 100. The lug 111 molding part is integrally set with the second molding part 230. The side of the first molding part 220 is also integrally formed with a third molding part 250. The cross-section of the third molding part 250 is trapezoidal, which is used for forming the shaft hole of the valve body 100 to meet the casting requirements of different valve bodies 100.

[0038] Reference Figure 4The outer mold assembly 410 is connected to a fixing plate 413, which is located at the connection position of the first mold shell 411 and the second mold shell 412, and is used to fix the first mold shell 411 and the second mold shell 412. After the first mold shell 411 and the second mold shell 412 are connected by the fixing plate 413, they are fitted onto the outside of the sand core 420. Sand is then injected and compacted through the sand injection gap 401 between the outer peripheral surface of the sand core 420 and the inner surface of the outer mold assembly 410. The outer mold is then removed, and the sand core 420 after sand injection is positioned and fitted with the forming mold of the outer surface of the butterfly valve to form a cavity. Molten metal is injected and cast, and then the mold is demolded. In some embodiments, the fixing plate 413 is provided with a plurality of first fixing holes, the first mold shell 411 is provided with a second fixing hole, and the second mold shell 412 is provided with a third fixing hole. The plurality of first fixing holes can simultaneously correspond to the second fixing hole and the third fixing hole, and the first mold shell 411 and the second mold shell 412 are fixedly connected by fasteners. The first mold shell 411 and the second mold shell 412 are fixedly connected by fasteners, and the first mold shell 411 and the second mold shell 412 are simultaneously tightened by the fixing plate 413, so as to ensure the connection stability and compressive strength of the outer mold assembly 410.

[0039] Reference Figure 1 and Figure 4 The central column 440 is provided with a through hoisting hole 441, which is used for hoisting equipment to pass through and move the sand core 420. It is easy to understand that the sand core 420 needs to be placed vertically during sand injection. If the round tube sand core 420 is placed vertically, it is difficult to move it with hoisting equipment, and it is difficult to fix the hoisting equipment to the sand core 420. However, the central column 440 is provided with a hoisting hole 441, which is located near the opening of the channel 421 of the sand core 420. This allows the hoisting equipment to be securely connected to the hoisting hole 441, which is convenient for transportation and handling.

[0040] Reference Figure 2 The base 210 has a positioning step 260 around its periphery. When the first molding part 220 and the second molding part 230 are pressed down to the rated depth in the casting sand, the positioning step 260 abuts against the top wall of the upper sand box 310 or the lower sand box 320. This positioning step 260, when pressed down to the rated depth in the casting sand, serves to position the depth to which the molding assembly 200 is pressed down, facilitating operation.

[0041] In some embodiments, four support ribs 430 are provided, and the four support ribs 430 are arranged at a 90° angle to each other. That is, the four support ribs 430 are arranged in a "+" shape to ensure support strength. In other embodiments, the number of support ribs 430 may be greater to ensure the structural strength of the sand core 420, but this is not the only limitation.

[0042] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A mold for casting a butterfly valve body, used to cast the valve body, wherein the valve body is a cylindrical structure with a flow channel for fluid passage, and its outer wall is connected with a plurality of side plates, characterized in that, include: An inner surface forming mold includes a sand core and an outer mold assembly. The outer mold assembly is a hexagonal vertical structure with cylindrical hollowed-out sections inside, including a first mold shell and a second mold shell. The first mold shell and the second mold shell are spliced ​​together and fitted on the outside of the sand core. A sand injection gap is formed between the outer wall of the sand core and the inner wall of the outer mold assembly for sand injection. The sand core is a circular tube with a through channel. The channel is provided with multiple support ribs. One end of the support rib is connected to the inner wall of the sand core, and the other end is connected to a central column. The axis of the central column is collinear with the axis of the sand core. The multiple support ribs are arranged radially and evenly from the central column to the surrounding area. An outer surface forming mold includes a sand box assembly and a forming assembly. The sand box assembly includes an upper sand box and a lower sand box. The upper sand box can be inverted and stacked on top of the lower sand box, and has a clearance in the middle. The sand core can be embedded in the clearance after sand injection. The forming assembly is used to press into the upper sand box and the lower sand box to form a forming groove. It includes a base, a first forming part, and a semi-circular arc-shaped second forming part. The first forming part is a semi-cylinder integrally formed with the base, located on the top surface of the base, and its arc surface faces upward. It is used for forming the cylindrical outer surface of the valve body. The base is provided with multiple slots, which are symmetrically arranged along both sides of the first forming part. The end of the second forming part is provided with a shaft. The shaft is provided with an elastic tension sleeve. The shaft is inserted into the slot. The elastic tension sleeve is interference-fitted with the slot to fix the second forming part and the base. The inner wall of the second forming part is in close contact with the outer wall of the first forming part, and the connection is covered or coated with filler.

2. The mold for casting the butterfly valve body according to claim 1, characterized in that, The side wall of the insert shaft is provided with a fixing screw hole, and the elastic tension sleeve is provided with a corresponding fixing hole. A screw passes through the fixing hole, and the screw rotates toward the fixing screw hole to fix the elastic tension sleeve.

3. The mold for casting the butterfly valve body according to claim 1, characterized in that, The slot is detachably connected to a filler, the top surface of which is flush with the top surface of the base when inserted into the slot, and the gap between the filler and the base is also coated or covered with filler.

4. The mold for casting the butterfly valve body according to claim 1, characterized in that, The second molded part is connected to a lug molded part for lug casting of the valve body, and the lug molded part is integrally formed with the second molded part.

5. The mold for casting the butterfly valve body according to claim 1, characterized in that, A third molding is integrally formed on the side of the first molding part. The cross-section of the third molding part is trapezoidal and is used for forming the shaft hole of the valve body.

6. The mold for casting the butterfly valve body according to claim 1, characterized in that, The outer mold assembly is connected to a fixing plate, and the fixing plate is located at the connection position between the first mold shell and the second mold shell, for fixing the first mold shell and the second mold shell together.

7. The mold for casting the butterfly valve body according to claim 6, characterized in that, The fixing plate is provided with a plurality of first fixing holes, the first mold shell is provided with a second fixing hole, and the second mold shell is provided with a third fixing hole. The plurality of first fixing holes can simultaneously correspond to the second fixing hole and the third fixing hole, and the first mold shell and the second mold shell are respectively fixedly connected by fasteners.

8. The mold for casting the butterfly valve body according to claim 1, characterized in that, The central column is provided with a through hoisting hole, which is used to hoist the equipment through and move the sand core.

9. The mold for casting the butterfly valve body according to claim 1, characterized in that, The base is provided with a positioning step around its periphery. When the first molded part and the second molded part are pressed down into the casting sand to a rated depth, the positioning step abuts against the top wall of the upper sand box or the lower sand box.

10. The mold for casting the butterfly valve body according to claim 1, characterized in that, The support ribs are provided in four parts, and the four support ribs are arranged at a 90° angle between each other.

Images