Casting device and casting process for thick-wall copper mold

Abstract

The casting device comprises a top plate, a side plate and a bottom plate, a casting opening is formed in the middle of the top plate, four guide columns are symmetrically arranged at the four corners of the bottom of the top plate, and four positioning holes matched with the guide columns are symmetrically formed in the side plate and the bottom plate in a penetrating mode. The top plate, the side plate and the bottom plate are sequentially connected in a sliding mode through guide columns, the contact faces are tightly attached, two ejector pin through holes are symmetrically formed in the middle position of the top plate, two ejector pin holes corresponding to the ejector pin through holes in position are formed in the surface of the top of the bottom plate, ejector pins are installed in the ejector pin through holes and the ejector pin holes, and the ejector pins are arranged in the ejector pin through holes and the ejector pin holes. The top plate is connected with the bottom plate through an ejector pin; the casting thermal stress is reduced by increasing the stress release line of the top plate, and meanwhile, the service life of the copper mold in a high-temperature working environment is prolonged by adding rare earth elements to serve as a grain refiner and an inhibitor.

Description

Technical Field

[0001] The invention belongs to the technical field of casting, and in particular relates to a casting device and a casting process for a thick-wall copper mold. Background Art

[0002] In the copper pyrometallurgical smelting process, the casting quality of copper anode plates is a key factor that directly affects the quality and production cost of anode plates, and copper anode plate casting molds play a vital role in this process. Copper molds have long been the preferred mold material for many domestic copper smelting companies due to their simple casting equipment, relatively low production costs, and the ability to remelt and reuse waste molds. However, despite the many advantages of copper molds, their limited service life has become an important bottleneck restricting the production efficiency and cost control of copper anode plates.

[0003] In order to meet this challenge, the industry has taken a series of measures to extend the service life of copper molds. Among them, optimizing the cooling mechanism is one of the effective means currently used. By improving the spraying method of cooling water and increasing the cooling intensity, a thicker surface fine-grained area can be formed on the mold surface. This fine-grained area not only enhances the nucleation ability of the mold surface, but also helps to improve the heat resistance and wear resistance of the mold, thereby extending the service life of the mold to a certain extent.

[0004] However, although the existing technology has achieved certain results in extending the service life of copper molds, the service life of copper molds is still limited in the high temperature, high pressure and highly corrosive smelting environment. Therefore, how to further extend the service life of copper molds has become a technical problem that copper smelting companies need to solve urgently. Summary of the invention

[0005] The first purpose of the present invention is to provide a casting device for a thick-walled copper mold; the second purpose is to provide a casting process for the casting device for the thick-walled copper mold.

[0006] The first object of the present invention is achieved in this way, comprising a top plate, a side plate and a bottom plate, wherein a casting port is provided in the middle of the top plate, four guide pillars are symmetrically arranged at the four corners of the bottom of the top plate, four positioning holes adapted to the guide pillars are symmetrically provided through the side plate and the bottom plate, the top plate, the side plate and the bottom plate are symmetrically connected in sliding in sequence through the guide pillars, and the contact surfaces are tightly fitted, two ejector through holes are symmetrically provided in the middle of the top plate, two ejector holes corresponding to the positions of the ejector through holes are provided on the top surface of the bottom plate, ejectors are installed in the ejector through holes and the ejector holes, and the top plate and the bottom plate are connected through the ejector pins; The top plate comprises two symmetrically arranged upper templates, the two upper templates are tightly fitted, and the ejector pin through hole is located on one of the upper templates; The side plate comprises a first side template and a second side template which are symmetrically arranged in pairs, and the end surfaces of the first side template and the second side template are closely attached to each other in sequence to form an annular frame; A forming boss protruding upward is arranged on the top of the bottom plate, the forming boss is located in the side plate, and the ejector pin hole is located in the forming boss.

[0007] Preferably, the top surfaces of the two upper mold plates are provided with a reinforcement grid formed by splicing a plurality of ribs along the connection and the casting port, and the top surface of the reinforcement grid is symmetrically provided with four ear seats.

[0008] Preferably, a plurality of reinforcing ribs are symmetrically arranged on both sides of the top of the top plate away from the connection of the reinforcing grid.

[0009] Preferably, both end surfaces of the two first side templates are provided with protrusions, and both end surfaces of the two second side templates are provided with grooves matching the protrusions, and the protrusions of the two first side templates are snap-fitted with the grooves of the two second side templates to form side panels.

[0010] Preferably, the outer side of the side plate is provided with a plurality of weight-reducing cavities which are recessed inwardly.

[0011] Preferably, a supporting grid is provided at the bottom of the base plate.

[0012] The second object of the present invention is achieved by comprising pre-treatment, casting and post-treatment steps, specifically comprising: A. Pre-treatment: 1) Apply a mold release agent to the contact surface between the casting device of the thick-wall copper mold and the molten metal and preheat the mold for standby use; 2) placing the raw rare earth alloy block at the bottom of the casting ladle, and then pouring the copper liquid at a temperature of 1100-1300°C into the casting ladle and staying for 4-6 minutes until the rare earth alloy block and the copper liquid are fully mixed to obtain material a; B. Casting: After slagging, material a is cast to obtain thick-walled copper mold castings. The casting speed is fast at first and then slow. The fast casting is 120~135Kg / s, the slow casting is 20~30Kg / s, and the total casting time is controlled at 30~90s; C. Post-processing: Transfer the thick-walled copper mold casting to the cooling area for air cooling.

[0013] The specific operations are as follows: S1. Prepare the mold: assemble the mold, apply mold release agent on the contact surface between the mold and the molten metal and preheat it; S2. Prepare raw materials: rare earth alloy block and anode copper liquid. First, place the rare earth alloy block at the bottom of the casting ladle, and then pour the copper liquid into the casting ladle and let it stay for a certain period of time. S3, casting: first scrape off the scum on the surface of the copper liquid, and then use gravity casting molding process to prepare thick-walled copper mold castings; S4, Cooling: After the copper liquid solidifies, the mold is removed immediately and it is transported to the cooling area for cooling.

[0014] Preferably, the mold comprises an upper mold unit, a lower mold unit, a side mold unit and an ejection unit, and each unit is assembled to form a casting cavity. The upper mold unit comprises a positioning plate and an upper mold plate, and two ejector holes are arranged on the positioning plate. The lower mold unit comprises a lower mold plate, and the upper bottom surface of the lower mold plate has a molding boss and an ejector hole, and the lower bottom surface has a honeycomb boss for heat dissipation, load bearing and anti-deformation. The side mold unit comprises a front side mold, a rear side mold, a left side mold and a right side mold, and the bottom of the side mold unit is slidably connected to the lower side surface of the upper mold plate, and the top of the side mold unit is slidably connected to the upper side surface of the lower mold unit. The ejection unit comprises two ejectors, and the ejector pins can be connected to the upper mold unit and the lower mold unit through preset ejector pin holes.

[0015] Preferably, the active ingredient of the release agent is BaSO4; the preheating adopts zoned preheating, wherein the preheating temperature of the lower mold unit and the ejection unit is 160-230°C, and the preheating temperature of the upper mold unit and the side mold unit is 110-160°C.

[0016] Preferably, the mass fraction of the rare earth alloy block is 0.5%, the component content is ω(RE1)=35%±3%, ω(RE2)=65%±3%; the temperature of the copper liquid is controlled at 1100-1300°C, and the residence time of the copper liquid in the crude copper bag is 5-8min.

[0017] Preferably, the copper liquid after slag removal is cast within 1 minute, the casting speed is fast at first and then slow, the fast casting is 120-135Kg / s, the slow casting is 20-30Kg / s, and the total casting time is 30-90s.

[0018] Preferably, the pouring port also has a riser function, and the specific pouring point is the upper-middle area of ​​the rectangular port, while the lower-middle area is the riser.

[0019] Preferably, the cooling method is air cooling.

[0020] Compared with the prior art, the invention has the following beneficial technical effects: by adding stress release lines to the upper mold unit, casting thermal stress is reduced, thereby achieving the purpose of increasing service life. At the same time, the complete mold is assembled from various units, which can be partially replaced and maintained, reducing production costs. By adding rare earth elements as grain refiners and inhibitors, the service life of the copper mold in a high-temperature working environment is increased.

[0021] The present invention has the following beneficial effects: (1) By setting up the top plate, which is spliced ​​by the upper mold plate, the stress release line of the top plate is increased, the thermal stress generated during the casting process is reduced, and the service life of the copper mold is improved.

[0022] (2) Guide columns are arranged on the side panels and the top panels connected thereto. The side panels are formed by clamping the first side template and the second side template, which facilitates the assembly and disassembly of the side panels and enables rapid positioning through the guide columns, thereby reducing the time required for the production process and improving work efficiency.

[0023] (3) By setting up reinforcing grids, reinforcing ribs and supporting grilles, the overall structural strength of the device can be strengthened, thereby increasing the overall service life of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the device of the present invention; Figure 2 is an exploded view of the device of the present invention; Figure 3 It is a schematic diagram of the side plate structure of the device of the present invention; Figure 4 It is a schematic diagram of the bottom structure of the bottom plate of the device of the present invention.

[0025] In the figure, 1-top plate, 2-side plate, 3-bottom plate, 4-casting port, 5-guide column, 6-positioning hole, 7-throw pin through hole, 8-throw pin hole, 9-throw pin, 10-upper template, 11-first side template, 12-second side template, 13-support grid, 14-molding boss, 15-reinforcement grid, 16-ear seat, 17-reinforcement rib, 18-protrusion, 19-groove, 20-weight-reducing cavity; Figure 5 It is a schematic diagram of the casting process flow of the present invention; Figure 6 Schematic diagram of the metallographic structure of the copper mold of the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described below in conjunction with the embodiments, but the present invention is not limited in any way. Any changes or substitutions made based on the teachings of the present invention belong to the protection scope of the present invention.

[0027] As shown in the accompanying drawings, a casting device for a thick-walled copper mold comprises a top plate 1, a side plate 2 and a bottom plate 3, wherein a casting port 4 is provided in the middle of the top plate 1, four guide pillars 5 are symmetrically arranged at the four corners of the bottom of the top plate 1, four positioning holes 6 adapted to the guide pillars 5 are symmetrically provided through the side plate 2 and the bottom plate 3, the top plate 1, the side plate 2 and the bottom plate 3 are symmetrically connected by sliding in sequence through the guide pillars 5, and the contact surfaces are tightly fitted, two ejector holes 7 are symmetrically provided in the middle of the top plate 1, two ejector holes 8 corresponding to the positions of the ejector holes 7 are provided on the top surface of the bottom plate 3, ejector holes 7 and ejector holes 8 are installed with ejector pins, and the top plate 1 and the bottom plate 3 are connected by the ejector pins; The top plate 1 includes two symmetrically arranged upper templates 10, the two upper templates 10 are tightly fitted, and the ejector pin through hole 7 is located on one of the upper templates 10; The side plate 2 includes a first side template 11 and a second side template 12 symmetrically arranged in pairs, and the end surfaces of the first side template 11 and the second side template 12 are closely attached to each other in sequence to form an annular frame; A forming boss 14 protruding upward is disposed on the top of the bottom plate 3 . The forming boss 14 is located inside the side plate 2 , and the ejector hole 8 is located inside the forming boss 14 .

[0028] When in use, the bottom plate 3 is laid flat on the working area, the ejector pin is installed in the ejector pin hole 8, and the first side template 11 and the second side template 12 are sequentially engaged through the protrusion 18 and the groove 19 to form the side plate 2. After the splicing is completed, the side plate 2 is aligned with the bottom plate 3 through the positioning hole 6 and laid flat on the surface of the bottom plate 3, and then the guide column 5 on an upper template 10 provided with an ejector pin through hole 7 is sequentially passed through the side plate 2 and the bottom plate 3, and the ejector pin is passed through the ejector pin through hole 7, and finally the guide column 5 on another upper template 10 is sequentially passed through the side plate 2 and the bottom plate 3 to complete the overall splicing of the device; the top plate 1 spliced ​​by the upper template 10 forms a stress release line, which can reduce the casting thermal stress generated during the casting process and achieve the effect of prolonging the service life of the device; the casting port 4 also has the function of a riser, and the specific casting point is the middle and upper area of ​​the casting port 4, and the middle and lower area is the riser.

[0029] As a specific technical solution of this embodiment, in order to strengthen the overall structure of the top plate 1 and prevent local deformation of the top plate 1 during the casting process, the top surfaces of the two upper mold plates 10 are provided with a reinforcing grid 15 composed of a number of ribs along the connection and the casting port 4, and the top surface of the reinforcing grid 15 is symmetrically provided with four ear seats 16, and the arrangement of the ear seats 16 facilitates the removal of the top plate 1.

[0030] As a technical solution to further improve the above embodiment, a plurality of reinforcing ribs 17 are symmetrically arranged on both sides of the top of the top plate 1 away from the connection of the reinforcing grid 15 , which can further strengthen the structure of the reinforcing grid 15 .

[0031] As a specific technical solution of this embodiment, in order to facilitate the positioning and installation of the side panel 2, the end faces of the two first side templates 11 are provided with protrusions 18, and the end faces of the two second side templates 12 are provided with grooves 19 matched with the protrusions 18. The protrusions 18 of the two first side templates 11 and the grooves 19 of the two second side templates 12 are snap-fitted into forming the side panel 2.

[0032] As a specific technical solution of this embodiment, in order to reduce the overall material usage of the device and strengthen the structure of the side plate 2, a plurality of weight-reducing cavities 20 which are recessed inwardly are provided on the outer side of the side plate 2.

[0033] As a specific technical solution of this embodiment, in order to strengthen the bottom structural strength of the device, optimize the bottom load-bearing performance, and achieve the heat dissipation effect, a support grid 13 is provided at the bottom of the bottom plate 3.

[0034] The process of thick-wall copper mold casting by the casting device of the thick-wall copper mold of the present invention includes pre-treatment, casting and post-treatment steps, specifically including: A. Pre-treatment: 1) Apply a mold release agent to the contact surface between the casting device of the thick-wall copper mold and the molten metal and preheat the mold for standby use; 2) placing the raw rare earth alloy block at the bottom of the casting ladle, and then pouring the copper liquid at a temperature of 1100-1300°C into the casting ladle and staying for 4-6 minutes until the rare earth alloy block and the copper liquid are fully mixed to obtain material a; B. Casting: After slagging, material a is cast to obtain thick-walled copper mold castings. The casting speed is fast at first and then slow. The fast casting is 120~135Kg / s, the slow casting is 20~30Kg / s, and the total casting time is controlled at 30~90s; C. Post-processing: Transfer the thick-walled copper mold casting to the cooling area for air cooling.

[0035] The active ingredient of the release agent described in step A 1) is BaSO4.

[0036] The preheating described in step A1) is performed by zone preheating, wherein the preheating temperature of the lower mold unit and the ejection unit is 160-230°C, and the preheating temperature of the upper mold unit and the side mold unit is 110-160°C.

[0037] The composition content of the rare earth alloy block described in step A2) is that the mass fraction of metal lanthanum (La) is 35%±3%, and the mass fraction of metal cerium (Ce) is 65%±3%.

[0038] Place the prepared rare earth alloy block at the bottom of the casting ladle, and then pour the 1200℃ copper liquid into the casting ladle, and use the high temperature and flushing effect of the copper liquid to melt the rare earth alloy block. The copper liquid stays in the casting ladle for 5 minutes to ensure that the rare earth alloy block can be fully mixed with the copper liquid. After the mixing is completed, the slag removal operation is carried out, and casting is carried out after there is no obvious slag on the surface. Position the casting point in the upper area of ​​the rectangular casting mouth, and then cast at 135Kg / s for 21s, 25Kg / s for 23s, and the total casting time is 44s. After the casting is completed, wait for the surface of the copper mold to be completely solidified, and transfer it to the cooling area for air cooling. Samples were taken for metallographic structure analysis and hardness testing. The results showed that the grain size was 40-60μm and the hardness was 50.1HB. Rare earth elements can not only refine the grains, but also improve the hardness performance.

Claims

1. A casting device for a thick-walled copper mold, characterized in that: The invention comprises a top plate (1), a side plate (2) and a bottom plate (3), wherein a casting port (4) is provided in the middle of the top plate (1), four guide pillars (5) are symmetrically arranged at the four corners of the bottom of the top plate (1), and four positioning holes (6) adapted to the guide pillars (5) are symmetrically provided through the side plate (2) and the bottom plate (3), wherein the top plate (1), the side plate (2) and the bottom plate (3) are symmetrically connected in sliding manner in sequence through the guide pillars (5), and the contact surfaces are tightly fitted, two ejector holes (7) are symmetrically provided in the middle of the top plate (1), and two ejector holes (8) corresponding to the positions of the ejector holes (7) are provided on the top surface of the bottom plate (3), ejector pins (9) are installed in the ejector holes (7) and the ejector holes (8), and the top plate (1) and the bottom plate (3) are connected via the ejector pins (9); The top plate (1) comprises two symmetrically arranged upper mold plates (10), the two upper mold plates (10) are tightly fitted together, and the ejector pin through hole (7) is located on one of the upper mold plates (10); The side plate (2) comprises a first side template (11) and a second side template (12) which are symmetrically arranged in pairs, and the end surfaces of the first side template (11) and the second side template (12) are closely attached to each other in sequence to form an annular frame; The top of the bottom plate (3) is provided with a molding boss (14) protruding upwards, the molding boss (14) is located in the side plate (2), and the ejector pin hole (8) is located in the molding boss (14).

2. The casting device for thick-walled copper mold according to claim 1, characterized in that: A reinforcement grid (15) composed of a plurality of ribs is provided on the top surfaces of the two upper mold plates (10) along the connection and the casting port (4), and four ear seats (16) are symmetrically provided on the top surface of the reinforcement grid (15).

3. The casting device of thick-wall copper mold according to claim 1, characterized in that: A plurality of reinforcing ribs (17) are symmetrically arranged on both sides of the top of the top plate (1) and away from the connection point of the reinforcing grid (15).

4. The casting device for thick-walled copper mold according to claim 1, characterized in that: The two end surfaces of the two first side templates (11) are provided with protrusions (18), and the two end surfaces of the two second side templates (12) are provided with grooves (19) that match the protrusions (18). The protrusions (18) of the two first side templates (11) and the grooves (19) of the two second side templates (12) are snap-fitted to form a side plate (2).

5. The casting device for thick-walled copper mold according to claim 4, characterized in that: The outer side of the side plate (2) is provided with a plurality of weight-reducing cavities (20) which are recessed inwardly.

6. The casting device of thick-wall copper mold according to claim 1, characterized in that: A supporting grid (13) is provided at the bottom of the base plate (3).

7. A process for casting thick-walled copper molds using a casting device for thick-walled copper molds as claimed in any one of claims 1 to 6, characterized in that: It includes pre-treatment, casting and post-treatment steps, including: A. Pre-treatment: 1) Apply a mold release agent to the contact surface between the casting device of the thick-wall copper mold and the molten metal and preheat the mold for standby use; 2) placing the raw rare earth alloy block at the bottom of the casting ladle, and then pouring the copper liquid at a temperature of 1100-1300°C into the casting ladle and staying for 4-6 minutes until the rare earth alloy block and the copper liquid are fully mixed to obtain material a; B. Casting: After slagging, material a is cast to obtain thick-walled copper mold castings. The casting speed is fast at first and then slow. The fast casting is 120~135Kg / s, the slow casting is 20~30Kg / s, and the total casting time is controlled at 30~90s; C. Post-processing: Transfer the thick-walled copper mold casting to the cooling area for air cooling.

8. The process according to claim 7, characterized in that The active ingredient of the release agent described in step A 1) is BaSO4.

9. The process according to claim 7, characterized in that The preheating described in step A1) is performed by zone preheating, wherein the preheating temperature of the lower mold unit and the ejection unit is 160-230°C, and the preheating temperature of the upper mold unit and the side mold unit is 110-160°C.

10. The process according to claim 7, characterized in that The composition content of the rare earth alloy block described in step A2) is that the mass fraction of metal lanthanum (La) is 35%±3%, and the mass fraction of metal cerium (Ce) is 65%±3%.

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