Scroll plate forming die, forming device and casting method thereof
By adopting low-pressure casting and secondary parting composite loading technology in scroll casting, combined with the design of ceramic doors and ceramic filters, the problem of forming difficulties in large parts of the middle of scroll is solved, and efficient and low-defect casting molding is achieved, improving the quality and service life of castings.
Patent Information
- Application Number
- CN202510269980.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-07
- Publication Date
- 2025-05-13
AI Technical Summary
When casting scroll discs, especially scroll lines with thick middle parts, it is difficult to form, and casting defects such as air rolling, shrinkage, and shrinkage often occur, which affects the appearance quality, mechanical properties and service life of the castings.
A scroll mold and molding device are adopted to achieve forced retraction through low-pressure casting and secondary parting composite loading technology, combined with the design of ceramic doors and ceramic filters, and improve the moldability of scroll teeth and fixed scroll teeth.
It effectively reduces casting defects, such as air rolling, shrinkage, shrinkage, etc., improves the density, mechanical properties and service life of the castings, and improves the yield rate, which meets the environmental protection requirements of energy conservation and emission reduction.
Smart Images
Figure CN119973084A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of scroll disk manufacturing, and in particular to a scroll disk forming mold, a forming device and a casting method thereof. Background Art
[0002] The scroll is the core component of the scroll compressor, and its performance directly determines the working efficiency and stability of the compressor. The scroll needs to withstand a variety of complex loads during operation, including pressure, inertia force, and contact force. Therefore, the scroll needs to have excellent wear resistance to ensure its long-term and stable service life.
[0003] At present, the fixed disk and the moving disk of the scroll disk are usually formed by die forging, and the material is mostly 4032 alloy. Although the die forging process can provide better mechanical properties, the spiral line structure of the moving scroll and the fixed scroll of the scroll disk is relatively complex. In particular, the inner and outer contours of the moving scroll and the fixed scroll need to be precisely meshed, requiring very strict matching clearance, which makes the forming process difficult and costly.
[0004] Therefore, the prior art began to use casting technology to manufacture the scroll disk. However, during the casting process, especially in the thick and large middle part of the scroll disk, the scroll profile is difficult to form, and it is often difficult to avoid casting defects such as air entrapment, shrinkage, and shrinkage. These defects not only affect the appearance quality of the casting, but also affect its mechanical properties, service life, and overall reliability. Summary of the invention
[0005] In order to solve the above technical problems, the purpose of the present invention is to provide a scroll disk forming mold, a forming device and a casting method thereof.
[0006] The technical solution provided by the present invention is as follows: A scroll disk forming die, comprising: A lower mold, the top surface of which is provided with a lower scroll disk forming cavity; An upper mold is stacked above the lower mold, and an upper scroll disk forming cavity coaxially arranged with the lower scroll disk forming cavity is provided on the bottom surface, a spirally extending vortex groove is coaxially arranged in the upper scroll disk forming cavity, and a spiral hole coaxially penetrating with the vortex groove is provided on the top surface of the upper mold; A swirl sleeve capable of passing through the spiral hole and engaging in the swirl groove; A gate is arranged on the bottom surface of the lower mold and is connected to the molding cavity of the lower scroll plate for injecting molding material.
[0007] Furthermore, the scroll disk forming mold further comprises: A lower cover plate is stacked below the lower mold and is provided with an injection channel connected to the gate; An upper cover plate is stacked on the upper mold and is provided with a through hole for the scroll sleeve to pass through; A pressure member is connected to the top end of the scroll sleeve and is used to apply external force to the scroll sleeve.
[0008] Furthermore, the gate position is provided with an openable and closable ceramic door, and the injection channel is provided with a ceramic filter; And / or, a cooling water pipe is provided on the bottom surface of the lower mold.
[0009] Further, the lower scroll plate molding cavity comprises a lower fixed vortex cavity and a lower movable vortex cavity, a lower connecting cavity is provided between the lower fixed vortex cavity and the lower movable vortex cavity, and the gate is connected to the lower connecting cavity; The upper scroll disk forming cavity includes an upper fixed vortex cavity coaxially arranged with the lower fixed vortex cavity and an upper movable vortex cavity coaxially arranged with the lower movable vortex cavity, and an upper connecting cavity corresponding to the lower connecting cavity is arranged between the upper fixed vortex cavity and the upper movable vortex cavity.
[0010] Furthermore, the top surface of the lower mold is provided with a lower chamber, the bottom surface of the upper mold is provided with an upper chamber, and the lower chamber and the upper chamber jointly define an exhaust chamber.
[0011] In another aspect, the present invention provides a scroll disk forming device, comprising: Holding furnace; A crucible, placed in the insulation furnace, used to contain the molding material and connected with an air inlet pipe; A sealing cover, which is disposed on the crucible and is provided with a through hole for the ceramic conduit to pass through; The vortex disk forming mold described in any one of the above embodiments is placed above the sealing cover and connected to the injection channel through the ceramic conduit.
[0012] Furthermore, a ceramic fiber filter is arranged in the ceramic conduit, a ceramic filter sheet is arranged in the injection channel, and the mesh number of the ceramic fiber filter is greater than the mesh number of the ceramic filter sheet.
[0013] In addition, the present invention also provides a casting method for a scroll disk, characterized in that the scroll disk forming device described in any one of the above embodiments is used, and the method comprises the following steps: Charging and melting: After putting the aluminum alloy raw materials into the crucible, slowly heat the holding furnace to 550℃~600℃, keep it warm for 60~80min, then heat it to 780~810℃ to melt, and keep it warm for 1h~2h; Refining and degassing: When the temperature of the aluminum liquid drops to 740℃~780℃, add environmentally friendly refining agent, turn on the degasser, and the rotor and baffle of the degasser will automatically sink for degassing. After the degassing is completed, remove the slag on the surface of the aluminum liquid; Mould treatment: Heat the scroll disc forming mould to 225-265℃ and apply paint on it; Low-pressure casting: Inert gas is introduced, the ceramic door is opened upward, and the molten aluminum is injected into the scroll disk forming mold under the conditions of a liquid pressure of 1.27-1.75 KPa / s and a liquid speed of 5-15 cm / s; after the molten aluminum is injected into the scroll disk forming mold, the pressure is maintained for 1.5-4.5 seconds under the condition of a holding pressure of 0.02-0.05 MPa; Secondary parting composite loading: After the aluminum liquid is pressurized for 1.5 to 4.5 seconds, when the aluminum liquid partially enters the semi-solid temperature range, pressure is applied to the scroll sleeve through the pressure-applying part to implement secondary parting composite loading, and the loading pressure is 85 to 125 MPa; after the secondary parting composite loading is completed, the gas pressure is increased to 0.05 to 0.11 MPa under the condition of a boost speed of 2.5 to 7.5 kPa / s, and the pressure is maintained at this pressure for 150 to 225 seconds to solidify the aluminum liquid to form a casting; after the aluminum liquid solidifies to form a casting, the inert gas is removed and the ceramic door is closed downward; the casting is cooled, and after cooling, the scroll disk forming mold is opened to take out the casting.
[0014] Furthermore, in the refining and degassing step, the rotor speed of the degasser is 425-482 r / min, the compressed air flow rate is 0.6-0.8 m³ / h, and the degassing time is 120-160 s.
[0015] Furthermore, the scroll casting method further comprises a solution aging treatment step, wherein the solution aging treatment step comprises the following steps: Primary solution treatment: heat the casting to 465±10℃ and keep it warm for 1 to 2 hours; Secondary solution treatment: After the primary solution treatment, heat the casting to 505±10℃, keep it warm for 6-8h, and then water cool it to 50℃; Aging strengthening: After the secondary solution treatment, heat the casting to 170±10℃, keep it for 7~9h, and then air cool it.
[0016] Compared with the prior art, the scroll disk forming mold provided by the embodiment of the present invention has at least the following technical effects: The scroll disk forming mold includes a lower mold, an upper mold, a scroll sleeve and a gate. Specifically, the top surface of the lower mold is provided with a lower scroll disk forming cavity; the upper mold is stacked above the lower mold, and the bottom surface is provided with an upper scroll disk forming cavity coaxially arranged with the lower scroll disk forming cavity, and a spirally extending vortex groove is coaxially arranged in the upper scroll disk forming cavity, and a spiral hole coaxially penetrating with the vortex groove is provided on the top surface of the upper mold; the scroll sleeve can be engaged in the vortex groove through the spiral hole; the gate is provided on the bottom surface of the lower mold and is connected to the lower scroll disk forming cavity for injecting molding materials. The forced shrinkage compensation effect of the scroll sleeve can improve the formability of the scroll profile of the movable scroll teeth and the fixed scroll teeth. The scroll disk produced using this mold has a clear contour and a smooth surface, and the density of the casting is uniform, and the overall quality is improved. In particular, during the casting process, casting defects in the thick and large middle part, such as air entrainment, shrinkage holes, shrinkage porosity, etc., are effectively reduced, thereby improving the density, mechanical properties and service life of the casting.
[0017] Since the scroll disk forming device includes the scroll disk forming mold in the above embodiment, it at least has the technical effects possessed by the scroll disk forming mold, which will not be described in detail here.
[0018] The scroll disk casting method realizes forced shrinkage compensation by adopting low-pressure casting and secondary parting composite loading technology, thereby improving the formability of the scroll profile of the movable scroll gear and the fixed scroll gear. The produced scroll disk has a clear contour and a smooth surface, and the density of the casting is uniform, and the overall quality is improved. In particular, during the casting process, casting defects in the thick and large middle part, such as air entrapment, shrinkage holes, and shrinkage porosity, are effectively reduced, thereby improving the density, mechanical properties, and service life of the casting. In addition, the casting method provided by the present invention not only effectively realizes the high strength and lightweight of the casting, but also improves the yield rate of the casting, can meet the technical requirements of "casting instead of forging" and "aluminum instead of steel" for lightweight parts, and meets the environmental protection requirements of energy conservation and emission reduction. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0020] Figure 1 It is a schematic diagram of the overall structure of a scroll disk forming mold in one embodiment of the present invention; Figure 2 for Figure 1 A schematic cross-sectional structure diagram of ; Figure 3 This is a schematic diagram of the overall structure of the lower mold in one embodiment of the present invention; Figure 4 It is a schematic diagram of the top view of the lower mold in one embodiment of the present invention; Figure 5 It is a schematic diagram of the overall structure of the upper mold in one embodiment of the present invention; Figure 6 It is a bottom view structural schematic diagram of an upper mold in one embodiment of the present invention; Figure 7 A schematic diagram of the top structure of an upper mold in one embodiment of the present invention; Figure 8 It is a schematic diagram of the overall structure of the scroll sleeve in one embodiment of the present invention; Fig. 9 It is a schematic cross-sectional structure diagram of a scroll disk forming device in one embodiment of the present invention; Fig.10 It is a schematic diagram of a process of a casting method of a scroll disk in one embodiment of the present invention; Fig.11 This is a schematic diagram of the equipment structure corresponding to the refining and degassing step in one embodiment of the present invention.
[0021] Reference numerals: 10. vortex disk forming mold; 11. lower mold; 111. lower fixed vortex cavity; 112. lower movable vortex cavity; 113. lower connecting cavity; 114. lower chamber; 12. upper mold; 121. upper fixed vortex cavity; 122. upper movable vortex cavity; 123. upper connecting cavity; 124. spiral hole; 125. upper chamber; 13. vortex sleeve; 14. gate; 141. ceramic door; 15. lower cover plate; 151. injection channel; 1511. ceramic filter; 16. upper cover plate; 161. through hole; 17. pressurized part; 18. cooling water pipe; 20. insulation furnace; 30. crucible; 40. sealing cover; 50. ceramic conduit; 51. ceramic fiber filter; 60. degasser. DETAILED DESCRIPTION
[0022] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present invention.
[0023] It should be noted that when an element is referred to as being "fixed on" or "set on" another element, it can be directly on the other element or indirectly set on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.
[0024] It should be understood that the orientation or position relationship indicated by terms such as "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "multiple" and "several" is two or more, unless otherwise clearly and specifically defined.
[0026] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with this technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantive technical significance. Any structural modification, change in proportion or adjustment of size, without affecting the effects and purposes that can be achieved by the present invention, should still fall within the scope of the technical contents disclosed by the present invention.
[0027] In recent years, the rapid development of new energy vehicles has made car air conditioning essential in automobile production. There are many types of car air conditioning compressors, among which compression type positive displacement compressors dominate. With the continuous improvement of compression energy saving, efficiency and noise performance requirements, scroll compressors have gradually gained wide popularity due to their superior performance. In the car air conditioning heating system of new energy vehicles, since the engine's waste heat cannot be used for air conditioning heating, it can only rely on electric heating and heat pump air conditioning heating. Therefore, energy-saving and lightweight scroll compressors have become the main direction of current research and development.
[0028] Scroll compressors are widely recognized as the technology leader of the third generation of positive displacement compressors. Their application areas include scroll vacuum pumps, scroll air compressors, scroll engines, scroll refrigeration compressors, scroll superchargers, etc., and they continue to expand with technological progress. Given their energy-saving and environmentally friendly characteristics, scroll compressors have shown broad application prospects against the backdrop of an increasingly severe global energy crisis.
[0029] The scroll is the core component of the scroll compressor, and its performance directly determines the working efficiency and stability of the compressor. The scroll needs to withstand a variety of complex loads during operation, including pressure, temperature, inertia force, and contact force. Therefore, the scroll needs to have excellent wear resistance to ensure its long-term and stable service life.
[0030] At present, the fixed disk and the moving disk of the scroll disk are usually formed by die forging, and the material is mostly 4032 alloy. Although the die forging process can provide better mechanical properties, the spiral line structure of the moving scroll and the fixed scroll of the scroll disk is relatively complex. In particular, the inner and outer contours of the moving scroll and the fixed scroll need to be precisely meshed, requiring very strict matching clearance, which makes the forming process more difficult, the required equipment has high precision requirements, the process is more complicated, and also leads to higher production costs.
[0031] Therefore, the prior art began to use casting technology to manufacture scroll disks. However, during the casting process, especially in the thick and large middle part of the scroll disk, the scroll profile is difficult to form, and it is often difficult to avoid casting defects such as air entrapment, shrinkage holes, and shrinkage. These defects not only affect the appearance quality of the casting, but also affect its mechanical properties, service life and overall reliability, limiting the wide application of casting technology in scroll disk production.
[0032] Please refer to the attached Figure 1 To Attachment Figure 8 As shown, an embodiment of the present invention provides a scroll disk forming mold 10, including a lower mold 11, an upper mold 12, a scroll sleeve 13 and a gate 14. The top surface of the lower mold 11 is provided with a lower scroll disk forming cavity; the upper mold 12 is stacked above the lower mold 11, and the bottom surface is provided with an upper scroll disk forming cavity coaxially arranged with the lower scroll disk forming cavity, and a spirally extending vortex groove is coaxially arranged in the upper scroll disk forming cavity, and the top surface of the upper mold 12 is provided with a spiral hole 124 coaxially penetrating with the vortex groove; the scroll sleeve 13 can pass through the spiral hole 124 and engage in the vortex groove; the gate 14 is arranged on the bottom surface of the lower mold 11, and is connected to the lower scroll disk forming cavity, for injecting molding material. Among them, the scroll sleeve 13 has a forced shrinkage compensation effect during the scroll disk molding process. The molding material is an aluminum alloy material, and an aluminum silicon alloy material can be selected, such as A356 hypoeutectic aluminum silicon alloy, ZL109 eutectic aluminum silicon alloy and A390 hypereutectic aluminum silicon alloy. From the binary phase diagram of aluminum-silicon alloy, we can see that the solid-liquid phase distance of this type of aluminum-silicon alloy material is relatively wide, so for a period of time after the start of crystallization, the melt still has good fluidity, and its strength between the liquid-solid phase line is still good. Therefore, this type of alloy has good casting properties and mechanical properties.
[0033] In this embodiment, the scroll disk molding mold 10 includes a lower mold 11, an upper mold 12, a scroll sleeve 13 and a gate 14. Specifically, the top surface of the lower mold 11 is provided with a lower scroll disk molding cavity; the upper mold 12 is stacked above the lower mold 11, and the bottom surface is provided with an upper scroll disk molding cavity coaxially arranged with the lower scroll disk molding cavity, and a spirally extending vortex groove is coaxially arranged in the upper scroll disk molding cavity, and the top surface of the upper mold 12 is provided with a spiral hole 124 coaxially penetrating with the vortex groove; the scroll sleeve 13 can pass through the spiral hole 124 and engage in the vortex groove; the gate 14 is arranged on the bottom surface of the lower mold 11, and is connected to the lower scroll disk molding cavity for injecting molding material. The forced shrinkage compensation effect of the scroll sleeve 13 can improve the formability of the vortex profile of the movable scroll tooth and the fixed scroll tooth. The scroll disk produced using this mold has a clear contour and a smooth surface, and the casting density is uniform, and the overall quality is improved. Especially during the casting process, casting defects in the thick and large middle parts, such as air entrapment, shrinkage holes, and shrinkage porosity, have been effectively reduced, thereby improving the density, mechanical properties and service life of the casting.
[0034] In some optional embodiments, the scroll disk forming mold 10 further includes a lower cover plate 15, an upper cover plate 16 and a pressure member 17. The lower cover plate 15 is stacked below the lower mold 11 and is provided with an injection channel 151 connected to the gate 14; the upper cover plate 16 is stacked above the upper mold 12 and is provided with a through hole 161 for the scroll sleeve 13 to pass through; the pressure member 17 is connected to the top of the scroll sleeve 13 to apply external force to the scroll sleeve 13. Specifically, the pressure member 17 includes a push rod, a scroll sleeve pressure plate and a push rod pressure plate. The push rod pressure plate is stacked below the scroll sleeve pressure plate. The push rod plays a guiding role, so that the scroll sleeve 13 can move smoothly along the push rod direction under the action of the scroll sleeve pressure plate.
[0035] In some optional embodiments, a ceramic door 141 that can be opened and closed is provided at the position of the gate 14, and a ceramic filter 1511 is provided in the injection channel 151. The ceramic door 141 is designed to be openable and closable. Under the action of the gas loading pressure, the molding material (such as aluminum liquid) will automatically push open the ceramic door 141; and after the gas loading pressure is removed, the ceramic door 141 will automatically close to reduce the molding material that has not yet completely solidified from flowing back into the injection channel 151. The ceramic filter 1511 further prevents the unsolidified metal aluminum slag from flowing back into the crucible 30. Through comparative tests, the present application found that for the vortex disk blank product with the ceramic door 141 and the ceramic filter 1511, the filter residue at the gate 14 almost does not fall into the crucible 30; while for the vortex disk blank product without the ceramic door 141 and the ceramic filter 1511, the filter residue at the gate 14 all falls into the crucible 30. The test results verify the effectiveness of the ceramic door 141 and the ceramic filter 1511, improve the quality of the casting, and reduce the backflow and residue of aluminum slag.
[0036] In some optional embodiments, a cooling water pipe 18 is provided on the bottom surface of the lower mold 11. Specifically, there is usually a thick and large area at the center of the scroll product, and these areas are prone to defects such as looseness. In order to effectively reduce this problem, a water cooling method is adopted. By providing a cooling water pipe 18 in the thick and large area, the solidification process of the aluminum liquid can be accelerated, thereby shortening the molding time of the area and reducing the generation of defects such as looseness.
[0037] In some optional embodiments, the lower scroll disk molding cavity includes a lower fixed vortex cavity 111 and a lower movable vortex cavity 112, a lower connecting cavity 113 is arranged between the lower fixed vortex cavity 111 and the lower movable vortex cavity 112, and the gate 14 is connected to the lower connecting cavity 113; the upper scroll disk molding cavity includes an upper fixed vortex cavity 121 coaxially arranged with the lower fixed vortex cavity 111 and an upper movable vortex cavity 122 coaxially arranged with the lower movable vortex cavity 112, and an upper connecting cavity 123 corresponding to the lower connecting cavity 113 is arranged between the upper fixed vortex cavity 121 and the upper movable vortex cavity 122.
[0038] In some optional embodiments, the lower scroll disk forming cavity includes two lower fixed vortex cavities 111 and two lower movable vortex cavities 112, the two lower fixed vortex cavities 111 are diagonally arranged, and the two lower movable vortex cavities 112 are diagonally arranged; the two lower fixed vortex cavities 111 and the two lower movable vortex cavities 112 are connected by a lower connecting cavity 113; the upper scroll disk forming cavity includes two upper fixed vortex cavities 121 and two upper movable vortex cavities 122, the two upper fixed vortex cavities 121 are diagonally arranged, and the two upper movable vortex cavities 122 are diagonally arranged; the two upper fixed vortex cavities 121 and the two upper movable vortex cavities 122 are connected by an upper connecting cavity 123.
[0039] In some optional embodiments, after the lower connecting cavity 113 and the upper connecting cavity 123 are molded together, a slag collecting groove is formed near the gate 14 , and the slag collecting groove can reduce the unsolidified metal aluminum slag from flowing back to the gate 14 .
[0040] In some optional embodiments, a lower chamber 114 is disposed on the top surface of the lower mold 11 , and an upper chamber 125 is disposed on the bottom surface of the upper mold 12 . The lower chamber 114 and the upper chamber 125 together define an exhaust chamber.
[0041] Please see attached Fig. 9One embodiment of the present invention further provides a vortex disk forming device, comprising a heat preservation furnace 20, a crucible 30, a sealing cover 40 and a vortex disk forming mold 10 of any one of the above embodiments; the crucible 30 is placed in the heat preservation furnace 20, used to contain the forming material, and is connected to an air inlet pipe; the sealing cover 40 is covered on the crucible 30, and is provided with a through hole for the ceramic conduit 50 to pass through, and the through hole is arranged at the center of the sealing cover 40; the vortex disk forming mold 10 is placed above the sealing cover 40, and is connected to the injection channel 151 through the ceramic conduit 50. Since the vortex disk forming device includes the vortex disk forming mold 10 in the above embodiment, it at least has the technical effects possessed by the vortex disk forming mold 10, which will not be repeated here.
[0042] In some optional embodiments, a ceramic fiber filter 51 is provided in the ceramic conduit 50, and a ceramic filter sheet 1511 is provided in the injection channel 151, and the mesh number of the ceramic fiber filter 51 is greater than the mesh number of the ceramic filter sheet 1511. Specifically, the present embodiment adopts a double-layer filtering mode to effectively improve the quality of the casting. The first layer of filtration is provided in the injection channel 151, and a ceramic filter sheet 1511 with a mesh number of 12-45 is used, which is mainly used to prevent the unsolidified metal aluminum slag from flowing back into the crucible 30 after the casting is completely solidified. The second layer of filtration is provided in the ceramic conduit 50, and a ceramic fiber filter 51 with a mesh number of 72-156 is used, which is intended to prevent fine impurities, aluminum slag and other impurities from flowing into the casting with the aluminum alloy solution, thereby ensuring the purity and quality of the casting.
[0043] In addition, please see the attached Fig.10 As shown, an embodiment of the present invention provides a casting method of a scroll disk, using the scroll disk forming device of any one of the above embodiments, comprising the following steps: S1. Charging and melting: After the aluminum alloy raw material is placed in the crucible 30, the holding furnace 20 is slowly heated to 550°C-600°C, and after being kept warm for 60-80 minutes, the temperature is further raised to 780-810°C for melting, and the temperature is kept warm for 1-2 hours; the above-mentioned heating and holding time periods are set according to the casting properties of the alloy material, aiming to reduce the occurrence of obvious gaps or pores in the aluminum liquid, so that the aluminum liquid can smoothly fill the mold in the subsequent casting process, and achieve a relatively ideal molding effect; S2. Refining and degassing: When the temperature of the aluminum liquid drops to 740℃~780℃, add environmentally friendly refining agent, turn on the degasser 60, and the rotor and baffle of the degasser 60 automatically sink to degas. After the degassing is completed, remove the scum on the surface of the aluminum liquid; the degasser 60 is a rotary degasser (please refer to the attached Fig.11As shown in the figure, the rotary degasser is placed above the holding furnace 20. After starting, the rotor and the baffle will sink into the aluminum liquid, generating a rotating flow to help separate the gas from the aluminum liquid. It should be further explained that after the degassing is completed, the slag on the surface of the aluminum liquid is turned over with a slag scoop, and then the slag on the surface of the aluminum liquid is cleaned to ensure that the surface of the aluminum liquid is clean to prevent the slag from affecting the casting quality. In addition, after the degassing is completed, the rotor rises, the rotary degasser is removed, and the vent holes on the rotor of the rotary degasser are cleared in time with special tools to ensure that the rotary degasser is not blocked and keeps in good working condition. S3, mold treatment: heat the scroll disk forming mold 10 to 225-265°C and apply paint to it; wherein, the scroll disk forming mold 10 is heated by an external mold temperature controller, and the temperature setting is based on the product characteristics and alloy casting properties to ensure that the scroll disk forming mold surface temperature is uniform and appropriate; S4, low-pressure casting: inert gas is introduced, and the ceramic door 141 is opened upward, so that the aluminum liquid is injected into the vortex disk forming mold 10 under the conditions of a liquid pressure of 1.27-1.75 KPa / s and a liquid speed of 5-15 cm / s; after the aluminum liquid is injected into the vortex disk forming mold 10, the pressure is maintained for 1.5-4.5 seconds under the condition of a holding pressure of 0.02-0.05 MPa; specifically, after the holding furnace 20 is placed under the vortex disk forming mold 10, dry inert gas (such as nitrogen or argon) is introduced, and after the dry inert gas enters the closed crucible 30 through the air inlet pipe, the ceramic door 141 is opened. 1 is opened upward, and the aluminum liquid is pushed by the inert gas through the ceramic conduit 50 into the scroll disk forming mold 10; after the aluminum liquid is injected, ensure that the aluminum liquid in the scroll disk forming mold 10 is maintained at a holding pressure of 0.02-0.05MPa for 1.5-4.5s, so that the aluminum liquid can fill every detail of the mold as much as possible, thereby preventing the casting from being underfilled or having pores; compared with other casting methods, low-pressure casting has better forming performance, and the scroll disk produced not only has a clear outline and a smooth surface, but also has a more uniform density distribution of the casting, reducing defects such as pores and looseness, and effectively improving the yield rate; S5. Secondary parting composite loading: After the aluminum liquid is kept under pressure for 1.5 to 4.5 seconds, when the aluminum liquid partially enters the semi-solid temperature range, pressure is applied to the scroll sleeve 13 through the pressure-applying member 17 to implement secondary parting composite loading. The loading pressure is 85 to 125 MPa to achieve forced shrinkage compensation, optimize the flow of aluminum liquid during the casting process, and make the spiral tooth vortex line of the scroll disk more accurately formed; at the same time, the secondary parting composite loading helps to improve the casting defects of thick and large parts of the casting, reduce the occurrence of defects such as pores and cold shuts, and improve the density and macroscopic mechanical properties of the casting; after the secondary parting composite loading is completed, the gas pressure is increased to 0.05 to 0.11 at a boost speed of 2.5 to 7.5 kPa / s. MPa, and maintain the pressure for 150 to 225 seconds to allow the molten aluminum to solidify and form a casting; after the molten aluminum solidifies and forms a casting, the inert gas is removed, and the ceramic door 141 is closed downward to prevent the unsolidified molten aluminum from flowing back into the crucible 30, so as to prevent the unsolidified molten aluminum from bringing back a large amount of semi-solid molten aluminum, a small amount of solidified aluminum blocks and aluminum slag. If these incompletely dissolved aluminum blocks and aluminum slag are used as filling raw materials for the next production of molten aluminum, the slag content in the product will increase, thereby affecting the quality of the casting; thereafter, the casting is cooled, and after cooling, the vortex disk forming mold 10 is opened to take out the casting.
[0044] The casting method provided by the present invention realizes forced shrinkage compensation by adopting low-pressure casting and secondary parting composite loading technology, thereby improving the formability of the vortex profile of the movable scroll gear and the fixed scroll gear. The produced scroll disk has a clear contour and a smooth surface, and the density of the casting is uniform, and the overall quality is improved. In particular, during the casting process, casting defects in thick and large parts, such as air entrapment, shrinkage holes, shrinkage porosity, etc., are effectively reduced, thereby improving the density, mechanical properties and service life of the casting. In addition, the casting method provided by the present invention not only effectively realizes the high strength and lightweight of the casting, but also improves the yield rate of the casting, can meet the technical requirements of "casting instead of forging" and "aluminum instead of steel" for lightweight parts, and meets the environmental protection requirements of energy conservation and emission reduction. During the flaw detection process of the blank, no shrinkage defects were found, which further verifies the reliability of the method of the present invention in improving the quality of castings.
[0045] It should be further explained that the pouring process of low-pressure casting is a bottom-up filling method, and the aluminum liquid smoothly fills the mold cavity under the action of external pressure. This filling method not only avoids the tendency of air entrainment, splashing and slag inclusion, but also effectively reduces the gas content of the scroll disk casting and ensures the quality of the casting. During the filling process, the aluminum liquid flows under the impetus of external pressure and can evenly fill the mold cavity, thereby obtaining a clear outline and good surface quality.
[0046] In addition, low-pressure casting is particularly suitable for changes in the size, volume and structure of scroll disk castings. At a lower filling speed, the aluminum alloy liquid flows smoothly from bottom to top into various parts of the cavity, which can effectively discharge the gas in the cavity and reduce or even eliminate the occurrence of defects such as pores. This smooth filling process improves the overall quality of the scroll disk casting and ensures the density uniformity and mechanical properties of the casting.
[0047] In some optional embodiments, in the refining and degassing step, the rotor speed of the degasser 60 is 425-482 r / min, the compressed air flow rate is 0.6-0.8 m³ / h, and the degassing time is 120-160 s. The above parameters are selected according to the casting properties of the alloy material.
[0048] In some optional embodiments, the casting method further comprises a solution aging treatment step, and the solution aging treatment step comprises the following steps: S601, primary solution treatment: heat the casting to 465±10℃ and keep it warm for 1~2h; S602, secondary solution treatment: After the primary solution treatment, the casting is heated to 505±10℃, kept at this temperature for 6-8h, and then water-cooled to cool the casting to 50℃; S603, aging strengthening: After the secondary solution treatment, the casting is heated to 170±10℃, kept warm for 7 to 9 hours, and then air-cooled.
[0049] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A scroll forming die, characterized in that: include: A lower mold, the top surface of which is provided with a lower scroll disk forming cavity; An upper mold is stacked above the lower mold, and an upper scroll disk forming cavity coaxially arranged with the lower scroll disk forming cavity is provided on the bottom surface, a spirally extending vortex groove is coaxially arranged in the upper scroll disk forming cavity, and a spiral hole coaxially penetrating with the vortex groove is provided on the top surface of the upper mold; A swirl sleeve capable of passing through the spiral hole and engaging in the swirl groove; A gate is arranged on the bottom surface of the lower mold and is connected to the molding cavity of the lower scroll plate for injecting molding material.
2. The scroll disk forming mold according to claim 1, characterized in that: Also includes: A lower cover plate is stacked below the lower mold and is provided with an injection channel connected to the gate; An upper cover plate is stacked on the upper mold and is provided with a through hole for the scroll sleeve to pass through; A pressure member is connected to the top end of the scroll sleeve and is used to apply external force to the scroll sleeve.
3. The scroll disk forming mold according to claim 2, characterized in that: The gate position is provided with an openable and closable ceramic door, and the injection channel is provided with a ceramic filter; And / or, a cooling water pipe is provided on the bottom surface of the lower mold.
4. The scroll disk forming mold according to claim 1, characterized in that: The lower scroll forming cavity comprises a lower fixed vortex cavity and a lower movable vortex cavity, a lower connecting cavity is provided between the lower fixed vortex cavity and the lower movable vortex cavity, and the gate is connected to the lower connecting cavity; The upper scroll disk forming cavity includes an upper fixed vortex cavity coaxially arranged with the lower fixed vortex cavity and an upper movable vortex cavity coaxially arranged with the lower movable vortex cavity, and an upper connecting cavity corresponding to the lower connecting cavity is arranged between the upper fixed vortex cavity and the upper movable vortex cavity.
5. The scroll disk forming mold according to claim 1, characterized in that: The top surface of the lower mold is provided with a lower cavity, the bottom surface of the upper mold is provided with an upper cavity, and the lower cavity and the upper cavity jointly define an exhaust cavity.
6. A scroll disk forming device, characterized in that: include: Holding furnace; A crucible, placed in the insulation furnace, used to contain the molding material and connected with an air inlet pipe; A sealing cover, which is disposed on the crucible and is provided with a through hole for the ceramic conduit to pass through; The vortex disk forming mold described in any one of claims 1 to 5 is placed above the sealing cover and connected to the injection channel through the ceramic conduit.
7. The scroll disk forming device according to claim 5, characterized in that: A ceramic fiber filter screen is arranged in the ceramic conduit, a ceramic filter sheet is arranged in the injection channel, and the mesh number of the ceramic fiber filter screen is greater than the mesh number of the ceramic filter sheet.
8. A method for casting a scroll disk, characterized in that: The vortex disk forming device as claimed in claim 6 or 7 is used, comprising the following steps: Charging and melting: After putting the aluminum alloy raw materials into the crucible, slowly heat the holding furnace to 550℃~600℃, keep it warm for 60~80min, then heat it to 780~810℃ to melt, and keep it warm for 1h~2h; Refining and degassing: When the temperature of the aluminum liquid drops to 740℃~780℃, add environmentally friendly refining agent, turn on the degasser, and the rotor and baffle of the degasser will automatically sink for degassing. After the degassing is completed, remove the slag on the surface of the aluminum liquid; Mould treatment: Heat the scroll disc forming mould to 225-265℃ and apply paint on it; Low-pressure casting: Inert gas is introduced, the ceramic door is opened upward, and the molten aluminum is injected into the scroll disk forming mold under the conditions of a liquid pressure of 1.27-1.75 KPa / s and a liquid speed of 5-15 cm / s; after the molten aluminum is injected into the scroll disk forming mold, the pressure is maintained for 1.5-4.5 seconds under the condition of a holding pressure of 0.02-0.05 MPa; Secondary parting composite loading: After the aluminum liquid is pressurized for 1.5 to 4.5 seconds and partially enters the semi-solid temperature range, pressure is applied to the scroll sleeve through the pressure-applying part to implement secondary parting composite loading, with a loading pressure of 85 to 125 MPa. After the secondary parting composite loading is completed, the gas pressure is increased to 0.05 to 0.11 MPa at a pressurization rate of 2.5 to 7.5 kPa / s, and the pressure is maintained at this pressure for 150 to 225 seconds to solidify the aluminum liquid to form a casting. After the aluminum liquid solidifies to form a casting, the inert gas is removed and the ceramic door is closed downward. The casting is cooled, and after cooling, the scroll disk forming mold is opened to take out the casting.
9. The scroll casting method according to claim 8, characterized in that: In the refining and degassing step, the rotor speed of the degasser is 425-482 r / min, the compressed air flow rate is 0.6-0.8 m³ / h, and the degassing time is 120-160 s.
10. The scroll casting method according to claim 8, characterized in that: The step of solution aging treatment is also included, and the solution aging treatment includes the following steps: Primary solution treatment: heat the casting to 465±10℃ and keep it warm for 1~2h; Secondary solution treatment: After the primary solution treatment, heat the casting to 505±10℃, keep it warm for 6-8h, and then water cool it to 50℃; Aging strengthening: After the secondary solution treatment, heat the casting to 170±10℃, keep it for 7~9h, and then air cool it.