A production and processing method of a curved enamel panel

Abstract

The present invention discloses a production and processing method for a curved enamel panel, specifically including the following steps: (1) mold design; (2) mold manufacturing; (3) product stamping: BL+PI / laser cutting, DR / drawing, TR+PI / laser cutting, CRST / sizing / inclined wedge sizing, CFL / flanging / inclined wedge flanging, RST / sizing, FL / flanging; (4) metalworking treatment: inner hole flanging and filling, secondary hemming and spot welding, rib welding, laser welding and grinding; (5) enameling process: pickling, spraying primer and topcoat, drying and enameling firing; (6) pressing process: using a nylon curved pressing table to shape the curved surface of the panel, thus obtaining the product. The curved enamel panel prepared by the present invention has a shape and size that completely meet the design requirements, with high product consistency, and the size and surface error of each panel are within 0.5 mm. The product size obtained by mold stamping is stable in quality and has high production efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of decorative materials, and more specifically to a production and processing method for a curved enamel panel. Background Art

[0002] Enamel panels have functions such as good corrosion resistance, chemical resistance, weather resistance, high temperature resistance, and easy cleaning. Therefore, enamel panels are playing an increasingly important role in the field of architectural decoration.

[0003] Currently, the shape of enamel panels is mainly flat. Although the flat shape is simple to manufacture, it lacks some design sense and appears a bit monotonous. The emergence of curved shapes brings various style changes to the product. In product design, the design of a curved surface can create a beautiful, round, and smooth texture for the product, giving people a comfortable feeling. Therefore, curved shapes are also increasingly applied to enamel panels.

[0004] According to the existing technology and equipment, a flat shape can be obtained through sheet metal bending. However, it is extremely difficult to manufacture a curved shape using only sheet metal processes, and it is also impossible to meet the consistency requirements of product processing.

[0005] Therefore, how to provide a production and processing method suitable for curved enamel panels is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a production and processing method for a curved enamel panel to solve the deficiencies in the existing technology.

[0007] To achieve the above purpose, the present invention adopts the following technical solutions:

[0008] A production and processing method for a curved enamel panel specifically includes the following steps:

[0009] (1) Mold Design

[0010] According to the product shape and accuracy requirements, combined with the existing press equipment, use 3D software for design modeling and CAE software for simulation and analysis of the stretching forming results;

[0011] (2) Mold Manufacturing

[0012] The mold is initially formed using a casting process, and then the casting is subjected to rough machining, finish machining, assembly, and grinding;

[0013] (3) Product Stamping

[0014] Including: BL+PI / Laser Cutting, DR / Drawing, TR+PI / Laser Cutting, CRST / Sizing / Inclined Wedge Sizing, CFL / Flanging / Inclined Wedge Flanging, RST / Sizing, FL / Flanging;

[0015] (4) Metalworking

[0016] Including: inner hole flanging and blanking, secondary hemming and spot welding, rib welding, laser welding and grinding;

[0017] (5) Enameling process

[0018] Including: pickling, spraying base glaze and surface glaze, drying and enameling firing;

[0019] (6) Pressing process

[0020] Use a nylon curved surface pressing table to shape the curved surface of the plate, and then the curved surface shaped enamel plate can be obtained.

[0021] Furthermore, in the above step (1), for the press equipment, it is necessary to consider whether the size and pressure of the press can meet the stamping requirements; the 3D software is UG (Interactive CAD / CAM system).

[0022] The beneficial effect of adopting the above further technical solution is that through mold design and feasibility analysis based on the curved surface shape, it is possible to avoid problems such as sheet interference, sheet wrinkling and cracking during stamping in advance.

[0023] Furthermore, in the above step (2), the lost foam casting process (also known as full-mold casting) is adopted for the casting process. The specific process is as follows: After brushing and drying the foam model with the same size as the casting with refractory material, it is buried in dry quartz sand or perlite sand, forsterite sand and vibrated for molding, and then poured under negative pressure to vaporize the foam model, and the liquid metal occupies the position of the model and forms the casting after solidification and cooling.

[0024] Furthermore, in the above step (3), in the product stamping production process, the raw material steel plate uses a 2mm thick zero-carbon steel plate, and all are laser cut. After cutting, the burrs at the cutting edge and the iron filings on the plate surface are cleaned.

[0025] The beneficial effect of adopting the above further technical solution is that the stamping production process is an advanced metal processing method, which is based on the plastic deformation of metal materials under force. The die and stamping equipment are used to process the sheet metal to obtain the required part shape and size. All raw material steel plates are laser cut, which can ensure the product accuracy and consistency. After cutting, the burrs at the cutting edge and the iron filings on the plate surface are cleaned, which can prevent damage to the stamping die.

[0026] Even further, in the above step (3), it also includes: after the curved surface of the plate is formed, the data of the plate surface is scanned and compared with the digital model. The position with a large plate surface error is repaired and stamped again until the plate surface size meets the design requirements.

[0027] Further, in the above step (4), the inner hole flanging and filling material is specifically as follows: for the slab processed by stamping, its main steel plate surface is integrally formed, and the remaining small components are completed by welding. Some stamping material-deficient positions also need to be completed by repair welding. Further, during the above inner hole flanging and filling material process, the filling material shapes are all simulated by 3D modeling and material splicing. All filling material cutting uses laser cutting, and all use whole plate cutting. Then, after bending, rounding, and deburring, the splicing spot welding with the slab can be carried out.

[0028] The beneficial effect of adopting the above further technical solution is that through the inner hole flanging and filling material, the accuracy of the filling material size can be guaranteed.

[0029] Further, in the above step (4), the secondary flanging spot welding is specifically as follows: before the material splicing of the secondary flanging, the slab needs to be trimmed in size and the inner hole flanging opening contour is actually measured to obtain an accurate primary flanging opening contour, forming a vector file, and then the drawing of the secondary flanging filling material and laser cutting can be carried out.

[0030] The beneficial effect of adopting the above further technical solution is that the primary flanging of the inner hole is formed by die flanging, and there are certain dimensional unevenness and angular rebound deviations. Therefore, the secondary flanging spot welding is carried out.

[0031] Further, in the above step (4), the rib welding is specifically as follows: the 304 stainless steel U-shaped strip with a cross-section is used as the main rib, and the cold-rolled L-shaped strip is used as the auxiliary rib for the angular positioning of each flanging and the contour positioning of the bird window hole. Further, during the above rib welding process, the size of the stainless steel U-shaped strip is 15 + 25 + 15 mm; the size of the cold-rolled L-shaped strip is 30 + 30 * 1.5 mm.

[0032] Further, in the above step (4), the laser welding is specifically as follows: by making full use of the fixation of the slab by the ribs at each position, the welding seams of the slab are within the trajectory error range of the robot laser welding head. With the help of the limit of the laser welding porous platform for the plate, the batch plates can be laser welded within a controllable area, and mass production of the same specifications can be achieved. Further, during the above laser welding process, after the workpiece is completed, a light transmission inspection needs to be carried out, and the unpenetrated positions are manually repaired by welding.

[0033] Further, in the above step (4), the grinding is specifically as follows: the rough grinding + fine repair treatment is carried out on each welding part to ensure that the surface structure of the welding position is smooth without sharp edges; the rust or scratches on the surface of the slab are polished with sandpaper. After sanding 3 times repeatedly, there are no traces visible to the eye and it is smooth and clean to the touch. Further, during the above grinding process, the rough grinding + fine repair treatment is carried out using a grinding wheel, a flat file and a round file, and sandpaper; No120 iron sandpaper is used for sanding.

[0034] Further, in the above step (5), the pickling is specifically as follows: Focus on controlling the mixing ratio concentration, soaking time, cleaning solution temperature, drying temperature, and drying time, and perform manual treatment on the special positions of the slab (the inner cavity of the slab is relatively closed and not conducive to water drainage).

[0035] Further, in the above step (5), the spraying of the base glaze and surface glaze is specifically as follows: Wet spraying of the base glaze on the reverse side, covering it completely, with a thickness of 70 - 100 μm and keeping it uniform, and adjusting the parameters of the spraying line; Manually re-spray the weak spraying positions, and then check whether there are defects such as static electricity sparks, powder flushing, powder spots, and powder shedding on the plate surface.

[0036] Further, in the above step (5), the drying is specifically as follows: Check and clean the accumulated glaze at the acute angles of the inner holes before drying conversion, and check the thickness of the base glaze on the reverse side.

[0037] Further, in the above step (5), the enameling firing is specifically as follows: Adjust the position of the stress suspension points, and raise the temperature to above 800 °C to completely fuse the glaze powder and the steel plate substrate.

[0038] The beneficial effects of adopting the above further technical solutions are as follows: Adjust the position of the stress suspension points to reduce the deformation of the plate during firing, and adopt the slow firing method with an ultra-low wire speed for spraying and firing. The enameling process is a high-temperature heat treatment link, and the glaze powder can only be completely fused with the steel plate substrate after the temperature reaches 800 °C. All indicators in the enameling furnace need to be kept in a stable state to ensure the consistency of color, with the color difference within the controllable range and meeting the requirements of the quality plan.

[0039] Further, in the above step (6), the nylon curved surface pressing platform is specifically as follows: Simulate the original positive and negative curved surfaces of the plate to form a compression layer by bonding the back of the enamel plate, the aluminum honeycomb core, and the 2.0 mm aluminum backboard with epoxy glue, and then use the upper pressing platform and the lower pressing platform to correct the curved surface of the fired enamel plate body. Further, during the above nylon curved surface pressing platform process, the amount of glue applied is 550 - 600 g / m 2 , which is 10 - 20% more than the usual amount of glue; Clean the glue on the back of the aluminum plate, and the backing plate must be flat; Tighten the screw rod assembly with a torque wrench, with a pressure of 50 NM; The pressing temperature is 20 - 30 °C, and the time is more than 16 h.

[0040] The beneficial effects of adopting the above further technical solutions are as follows: The pressing plate process is a process for shaping the curved surface of the plate. Enameling is a crucial test for the surface of the steel plate. The existence of the shape and the curved surface will lead to uneven cooling speeds in different regions, different release speeds of the original stress at high temperatures, and different situations of the plate surface rebounding. Therefore, adding an aluminum honeycomb and a backboard is the only measure that can absorb a part of the corrugation deformation. Among them, the upper pressing platform and the lower pressing platform are profiled according to the positive and negative curved surfaces of the enamel plate, so that the outer dimensions of the plate can be consistent with the design requirements after the pressing is completed.

[0041] As can be seen from the above technical solutions, compared with the prior art, the beneficial effects of the present invention are as follows:

[0042] 1. The production and processing method of the present invention includes die stamping and enamel firing. Specifically, die stamping includes three major parts: die design, die making, and product stamping, and enamel firing includes three major parts: metalworking treatment, enameling process, and pressing process. Among them, die stamping adopts the die stamping method for automobiles. After die debugging, the consistency of processing can be guaranteed to the greatest extent. Even if problems are found, adjustments can be made according to the actual situation, and the overall effect is better, and the processing cycle can be guaranteed.

[0043] 2. The curved surface shaped enamel board obtained by the present invention has a shaped size that completely meets the design requirements, with high product consistency, and the size and curved surface error of each board are within 0.5 mm. The product size obtained by die stamping is stable in quality and high in production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a flow chart of the lost foam casting process;

[0045] Figure 2 is a schematic diagram of foam molding;

[0046] Figure 3 is a comparison diagram of the data of the board surface after stamping and the digital model;

[0047] Figure 4 is a schematic diagram of the shaped steel plate after stamping;

[0048] Figure 5 is the feeding part (A);

[0049] Figure 6 is the feeding part (B);

[0050] Figure 7 is a schematic diagram of rib welding; wherein, 1 - main rib of stainless steel U-shaped strip, 2 - auxiliary rib of cold-rolled L-shaped strip;

[0051] Figure 8 is a schematic diagram of the pressing process; wherein, 3 - screw rod assembly, 4 - channel steel pressing strip, 5 - leveling channel steel, 6 - upper pressing table, 7 - aluminum honeycomb core, 8 - aluminum back plate, 9 - lower pressing table. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0052] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0053] Embodiment 1

[0054] Production and processing method of surface modeling enamel plate, specifically including the following steps:

[0055] (1) Mold design

[0056] According to the product shape and precision requirements, combined with the existing press equipment, it is necessary to consider whether the size and pressure of the press can meet the stamping requirements, and use 3D software UG for design modeling and CAE software for simulation and analysis of the stretching forming results;

[0057] (2) Mold making

[0058] The mold is initially formed by the lost casting process (the flow chart is as shown in Figure 1 and the foaming forming schematic diagram is as shown in Figure 2 ). After brushing and drying the foam model with the same size as the casting with refractory materials, it is buried in dry quartz sand for vibration molding, and then poured under negative pressure to vaporize the foam model. The liquid metal occupies the model position and forms a casting after solidification and cooling; then the casting is rough machined, finish machined, assembled, and ground;

[0059] (3) Product stamping

[0060] Including: BL+PI / Laser cutting, DR / Drawing, TR+PI / Laser cutting, CRST / Shaping / Inclined wedge shaping, CFL / Flanging / Inclined wedge flanging, RST / Shaping, FL / Flanging; among them, the raw material steel plate uses a 2mm thick zero-carbon steel plate, and all are laser cut. After cutting, the edge burrs are cleaned and the iron filings on the plate surface are cleaned; after the surface of the plate is formed into a curved surface, the data of the plate surface is scanned and compared with the digital model (the comparison diagram of the plate surface data after stamping and the digital model is as shown in Figure 3 ). The position with a large error on the plate surface is repaired and stamped again until the size of the plate surface meets the design requirements (the schematic diagram of the shaped steel plate after stamping is as shown in Figure 4 );

[0061] (4) Metalworking treatment

[0062] a. Inner hole flanging and filling: For the blank of stamping processing, the main surface of the steel plate is integrally formed, and the rest of the small parts are completed by welding. Some positions lacking materials in stamping also need to be completed by repair welding; among them, the filling shape is all simulated by 3D modeling and piecing, and all filling blanking uses laser blanking and uses the whole plate for blanking. After bending, rounding, and deburring, it can be used for splicing and spot welding with the blank (the filling part is as shown in Figures 5-6 );

[0063] b. Secondary flanging and spot welding: Before piecing the secondary flanging, it is necessary to trim the size of the blank and measure the contour of the inner hole flanging opening to obtain the accurate contour of the first flanging opening and form a vector file before the drawing and laser cutting of the secondary flanging filling can be carried out;

[0064] c. Tie bar welding: Use a 304 stainless steel U-shaped bar 1 with a cross-section of 15 + 25 + 15 mm as the main bar, and a cold-rolled L-shaped bar 2 with a cross-section of 30 + 30 * 1.5 mm as the auxiliary bar to position the angles of each folded edge and the contour of the bird window hole (the schematic diagram of tie bar welding is as shown in Figure 7 shown);

[0065] d. Laser welding: Utilize the full fixation of the tie bars at each position to the slab, so that the welding seams of the slab are within the trajectory error range of the robot laser welding head. With the help of the laser welding porous platform to limit the position of the plates, batch plates can be laser welded within a controllable area, and mass production of the same specification can be achieved; After the workpiece is completed, light transmission inspection needs to be carried out, and manual repair welding is performed on the positions where penetration welding is not achieved;

[0066] e. Grinding: Use a grinding wheel, flat file, round file, and sandpaper to perform rough grinding and fine repair on each welding part to ensure that the surface structure of the welding position is smooth without sharp edges; Use No. 120 iron sandpaper to polish the rust or scratches on the surface of the slab 3 times repeatedly, and there are no traces visible to the eye and it is smooth and flat to the touch;

[0067] (5) Enameling process

[0068] a. Pickling: Focus on controlling the mixing ratio concentration, soaking time, cleaning solution temperature, drying temperature, and drying time, and perform manual treatment on special positions of the slab;

[0069] b. Spraying primer and glaze: Apply wet primer on the reverse side, covering it completely, with a thickness of 80 μm and keeping it uniform, and adjust the parameters of the spraying line; Manually re-spray the weak spraying positions, and then check whether there are electrostatic sparks, powder flushing, powder spots, and powder shedding on the plate surface;

[0070] c. Drying: Check the accumulation of glaze at the acute angles of the inner holes and clean it before drying conversion, and check the thickness of the primer on the reverse side;

[0071] d. Enamel firing: Adjust the position of the stress hanging points, and raise the temperature to 800 °C to completely fuse the enamel powder and the steel plate substrate;

[0072] (6) Pressing process

[0073] Use a nylon curved pressing table to simulate the original positive and negative curved surfaces of the plate, form a compressive layer by bonding the back of the enamel plate, the aluminum honeycomb core 7, and the 2.0 mm aluminum back plate 8 with epoxy glue, and then use the upper pressing table 6 and the lower pressing table 9 to correct the curved surface of the fired enamel plate body (the schematic diagram of the pressing process is as shown in Figure 8 shown); Among them, the amount of glue applied is 580 g / m 2; Clean the glue on the back of the aluminum plate, and the backing plate must be flat; Tighten the screw rod assembly with a torque wrench, with a pressure of 50 NM; The crimping temperature is 25 °C and the time is 16 h; Shape the curved surface of the plate to obtain a curved surface enamel plate.

[0074] Example 2

[0075] A production and processing method for a curved surface enamel plate, specifically including the following steps:

[0076] (1) Mold design

[0077] According to the product shape and precision requirements, combined with the existing press equipment, it is necessary to consider whether the size and pressure of the press can meet the stamping requirements, and use 3D software UG for design and modeling, and CAE software for simulation and analysis of the stretching forming results;

[0078] (2) Mold making

[0079] The mold is initially formed by the lost casting process (the flow chart is as shown in Figure 1 shown, and the foaming forming schematic diagram is as shown in Figure 2 shown). After brushing and drying the foam model with the same size as the casting with refractory materials, it is buried in dry perlite sand and vibrated to form a mold, and then poured under negative pressure to vaporize the foam model, and the liquid metal occupies the model position and forms a casting after solidification and cooling; Then, rough machining, finish machining, assembly, and grinding are carried out on the casting;

[0080] (3) Product stamping

[0081] Including: BL+PI / Laser cutting, DR / Drawing, TR+PI / Laser cutting, CRST / Shaping / Inclined wedge shaping, CFL / Flanging / Inclined wedge flanging, RST / Shaping, FL / Flanging; Among them, the raw material steel plate uses a 2-mm-thick zero-carbon steel plate, and all are laser cut. After cutting, the burrs on the cutting edge and the iron filings on the plate surface are cleaned; After the curved surface of the plate is formed, the data of the plate surface is scanned and compared with the digital model (the comparison diagram of the plate surface data after stamping and the digital model is as shown in Figure 3 shown). The position with a large error on the plate surface is repaired and stamped again until the plate surface size meets the design requirements (the schematic diagram of the shaped steel plate after stamping is as shown in Figure 4 shown);

[0082] (4) Metalworking

[0083] a. Inner hole flanging and filling: For the blank of stamping processing, the main steel plate surface of the steel plate is integrally formed, and the rest of the small parts are completed by welding. Some positions lacking materials in stamping also need to be completed by filling welding; Among them, the filling shape is all simulated by 3D modeling and piecing, and all filling materials are cut by laser, and all are cut from the whole plate. After bending, rounding, and deburring, they can be joined and spot welded to the blank (the filling part is as shown in Figures 5-6 shown);

[0084] b. Secondary hemming spot welding: Before the material splicing of the secondary hemming, the size trimming of the slab and the actual measurement of the inner hole flanging profile need to be carried out to obtain the accurate primary flanging profile, form a vector file, and then the drawing of the secondary hemming filling material and laser cutting can be carried out;

[0085] c. Rib welding: Use a 304 stainless steel U-shaped strip 1 with a cross-section of 15 + 25 + 15 mm as the main rib, and a cold-rolled L-shaped strip 2 with a size of 30 + 30 * 1.5 mm as the auxiliary rib to position the angles of each hemming and the profile of the bird window hole (the schematic diagram of rib welding is as Figure 7 shown);

[0086] d. Laser welding: Utilize the sufficient fixation of the slab by the ribs at each position to make the welding seams of the slab within the trajectory error range of the robot laser welding head. With the help of the limiting of the plate by the laser welding porous platform, the batch plates can be laser welded within a controllable area, and mass production of the same specification can be achieved; After the workpiece is completed, light transmission inspection needs to be carried out, and manual repair welding is performed on the unpenetrated positions;

[0087] e. Grinding: Use grinding wheels, flat files and round files, and sandpaper to carry out rough grinding + fine repair on each welding part to ensure that the surface structure of the welding position is smooth without sharp edges; Use sandpaper to carry out fine polishing on the rust or scratches on the surface of the slab. After sanding with No. 120 iron sandpaper 3 times, there are no traces visible to the eye and it is smooth and clean to the touch;

[0088] (5) Glazing process

[0089] a. Pickling: Focus on controlling the mixing ratio concentration, soaking time, cleaning solution temperature, drying temperature and drying time, and perform manual treatment on special positions of the slab;

[0090] b. Spraying primer and glaze: Spray the primer wet on the reverse side, covering it completely, with a thickness of 70 μm and keeping it uniform, and adjust the parameters of the spraying line; Manually re-spray the weak spraying positions, and then check whether there are static electricity sparks, powder flushing, powder spots and powder dropping on the plate surface;

[0091] c. Drying: Check the accumulation of glaze at the acute angles of the inner hole and clean it before drying conversion, and check the thickness of the primer on the reverse side;

[0092] d. Enameling: Adjust the position of the hanging points for stress, and heat up to 800 °C to completely fuse the glaze powder and the steel plate substrate;

[0093] (6) Pressing process

[0094] Use a nylon curved pressing table to simulate the original positive and negative curves of the plate, form a compressive layer by bonding the back of the enamel plate, the aluminum honeycomb core 7, and the 2.0 mm aluminum back plate 8 with epoxy glue, and then use the upper pressing table 6 and the lower pressing table 9 to correct the curved surface of the fired enamel plate body (the schematic diagram of the pressing process is asFigure 8 as shown; among them, the sizing amount is 550 g / m 2 ; Clean the glue on the back of the aluminum plate, and the backing plate must be flat; Fasten the screw rod assembly with a torque wrench, and the pressure is 50 NM; The crimping temperature is 20 °C and the time is 16 h; Shape the curved surface of the plate to obtain a curved surface shaped enamel plate.

[0095] Example 3

[0096] A production and processing method for a curved surface shaped enamel plate, specifically including the following steps:

[0097] (1) Mold design

[0098] According to the product shape and precision requirements, combined with the existing press equipment, it is necessary to consider whether the size and pressure of the press can meet the stamping requirements, and use 3D software UG for design modeling and CAE software for simulation and analysis of the stretching forming results;

[0099] (2) Mold making

[0100] The mold is initially formed using the lost casting process (the flow chart is as Figure 1 shown, and the foaming forming schematic diagram is as Figure 2 shown). After brushing and drying the refractory material on the foam model with the same size as the casting, it is buried in dry forsterite sand for vibration molding, and then poured under negative pressure to vaporize the foam model, and the liquid metal occupies the model position and forms a casting after solidification and cooling; Then, rough machining, finish machining, assembly, and grinding are carried out on the casting;

[0101] (3) Product stamping

[0102] Including: BL+PI / Laser cutting, DR / Drawing, TR+PI / Laser cutting, CRST / Shaping / Inclined wedge shaping, CFL / Flanging / Inclined wedge flanging, RST / Shaping, FL / Flanging; Among them, the raw material steel plate uses a 2 mm thick zero-carbon steel plate, and all are laser cut. After cutting, the burrs on the cutting edge and the iron filings on the plate surface are cleaned; After the curved surface of the plate is formed, the data of the plate surface is scanned and compared with the digital model (the comparison diagram of the plate surface data after stamping and the digital model is as Figure 3 shown). The position with a large error on the plate surface is repaired and stamped again until the plate surface size meets the design requirements (the schematic diagram of the shaped steel plate after stamping is as Figure 4 shown);

[0103] (4) Metalworking treatment

[0104] a. Inner hole flanging and filling: For the slab blank in stamping processing, its main steel plate surface is integrally formed, and the remaining small components are completed by welding. Some stamping material-deficient positions also need to be completed by repair welding. Among them, the filling shapes are all simulated by 3D modeling and material splicing. All filling blanking uses laser blanking, and all use whole plate blanking. After bending, rounding, and deburring, it can be used for splicing spot welding with the slab blank (the filling part is as shown in Figures 5-6 ).

[0105] b. Secondary flanging and spot welding: Before splicing the materials for secondary flanging, it is necessary to trim the dimensions of the slab blank and measure the inner hole flanging port contour actually to obtain an accurate primary flanging port contour, form a vector file, and then the drawing of the secondary flanging filling and laser cutting can be carried out.

[0106] c. Rib welding: Use a 304 stainless steel U-shaped bar 1 with a cross-section of 15 + 25 + 15 mm as the main rib, and a cold-rolled L-shaped bar 2 with a cross-section of 30 + 30 * 1.5 mm as the auxiliary rib for angle positioning and bird window hole contour positioning of each flanging (the rib welding schematic diagram is as shown in Figure 7 ).

[0107] d. Laser welding: Utilize the full fixation of the slab blank by the ribs at each position, so that the welding seams of the slab blank are within the trajectory error range of the robot laser welding head. With the help of the limit of the laser welding porous platform for the plate, the batch plates can be laser welded within a controllable area, and mass production of the same specifications can be achieved. After the workpiece is completed, it is necessary to conduct a light transmission inspection, and the unpenetrated positions are manually repaired and welded.

[0108] e. Grinding: Use a grinding wheel, flat file, round file, and sandpaper to carry out rough grinding + fine repair treatment on each welding part to ensure that the surface structure of the welding position is smooth and has no sharp edges; use sandpaper to carry out fine polishing treatment on the rust or scratches on the surface of the slab blank. After sanding with No. 120 iron sandpaper three times repeatedly, there are no traces visible to the eye and it is smooth and clean to the touch.

[0109] (5) Porcelain enameling process

[0110] a. Pickling: Focus on controlling the mixing ratio concentration, soaking time, cleaning solution temperature, drying temperature, and drying time, and conduct manual treatment on special positions of the slab blank.

[0111] b. Spraying primer glaze and top glaze: Apply wet primer glaze on the reverse side, covering it completely, with a thickness of 100 μm and keeping it uniform. Adjust the parameters of the spraying line; conduct manual supplementary spraying on the weak spraying positions, and then check whether there are static electricity sparks, powder flushing, powder spots, and powder dropping on the plate surface.

[0112] c. Drying: Check the accumulation of glaze at the inner hole acute angle and clean it before drying conversion, and check the thickness of the primer glaze on the reverse side.

[0113] d. Porcelain enameling firing: Adjust the position of the force-bearing hanging points, and raise the temperature to 800 °C to completely fuse the glaze powder and the steel plate substrate.

[0114] (6) Pressing Plate Process

[0115] Use a nylon curved pressing table to simulate the original positive and negative curved surfaces of the plate. A compressive layer is formed by bonding the back of the enamel plate, the aluminum honeycomb core 7, and the 2.0 mm aluminum backplate 8 with epoxy glue. Then, use the upper pressing table 6 and the lower pressing table 9 to correct the curvature of the fired enamel plate body (the schematic diagram of the pressing plate process is as Figure 8 shown); among them, the glue application amount is 600 g / m 2 ; Clean the glue on the back of the aluminum plate, and the backing plate must be flat; tighten the screw rod assembly with a torque wrench, and the pressure is 50 NM; the pressing temperature is 30 °C, and the time is 16 h; shape the curved surface of the plate to obtain the curved surface shaped enamel plate.

[0116] Performance Test

[0117] 1. Inspection of Stamped Finished Products

[0118] Take the stamped finished products obtained in step (3) of Example 1 and inspect their length, diagonal, flanging height, angle, outer corner R, and arc conformity respectively.

[0119] The results are shown in Table 1.

[0120] Table 1 Inspection Results of Stamped Finished Products

[0121]

[0122] As can be seen from Table 1, the dimensions of the stamped finished products in step (3) of Example 1 meet the requirements.

[0123] 2. Inspection of Curved Surface Shaped Enamel Plate Finished Products

[0124] Take the curved surface shaped enamel plate finished products obtained in step (6) of Example 1 and inspect their porcelain peeling, fish scale explosion, air bubbles and sand holes, cracks, powder spots, and orange peel wrinkles respectively.

[0125] The results are shown in Table 2.

[0126] Table 2 Inspection Results of Curved Surface Shaped Enamel Plate Finished Products

[0127]

[0128] As can be seen from Table 2, there are no enamel defects on either the front or the side of the curved surface shaped enamel plate finished products in step (6) of Example 1.

[0129] The foregoing description of the disclosed embodiments enables those skilled in the art to practice or use the present invention. Various modifications to these embodiments will be readily 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. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A production and processing method of a curved enamel plate, characterized in that, Specifically, it includes the following steps: (1) Mold design According to the shape and precision requirements of the product, combined with the existing press equipment, use 3D software for design modeling and CAE software for simulating and analyzing the stretching forming results; (2) Mold manufacturing The mold is initially formed by casting process, and then the casting is subjected to rough machining, finish machining, assembly, and grinding; (3) Product stamping Including: BL+PI, DR, TR+PI, CRST, CFL, RST, FL; (4) Metalworking treatment Including: inner hole flanging and filling, secondary hemming spot welding, rib welding, laser welding, and grinding; The specific process of the inner hole flanging and filling is as follows: for the blank of stamping process, its main steel plate surface is integrally formed, and the remaining small components are completed by welding. Some stamping material-deficient positions also need to be completed by repair welding; during the inner hole flanging and filling process, the filling shape is simulated by 3D modeling and material splicing. All filling blanking is carried out by laser blanking, and the whole plate is used for blanking. Then, it can be spliced and spot welded to the blank after bending, rounding, and deburring; The specific process of the secondary hemming spot welding is as follows: before the material splicing of the secondary hemming, the blank needs to be trimmed in size and the contour of the inner hole flanging opening is actually measured to obtain the accurate contour of the first flanging opening, forming a vector file, and then the drawing and laser cutting of the secondary hemming filling material can be carried out; The specific process of the rib welding is as follows: the 304 stainless steel U-shaped bar with a cross-section is used as the main rib, and the cold-rolled L-shaped bar is used as the auxiliary rib for angle positioning of each hemming and contour positioning of the bird window hole; during the rib welding process, the size of the stainless steel U-shaped bar is 15+25+15mm; the size of the cold-rolled L-shaped bar is 30+30*1.5mm; The specific process of the laser welding is as follows: by making full use of the fixation of the blank by the ribs at each position, the welding seams of the blank are within the trajectory error range of the robot laser welding head. With the help of the limit of the laser welding porous platform for the plate, the batch plates can be laser welded within a controllable area, and mass production of the same specification can be achieved; during the laser welding process, after the workpiece is completed, a light transmission inspection needs to be carried out, and the unpenetrated positions are manually repaired by welding; The specific process of the grinding is as follows: rough grinding + finishing treatment is carried out on each welding part to ensure that the surface structure of the welding position is smooth without sharp edges; the rust or scratches on the surface of the blank are polished with sandpaper. After sanding 3 times, there is no trace visible to the eye and it is smooth and smooth to the touch; during the grinding process, rough grinding + finishing treatment is carried out using a grinding wheel, a flat file and a round file, and sandpaper; No120 iron sandpaper is used for sanding; (5) Enameling process Including: pickling, spraying primer glaze and surface glaze, drying, and enamel firing; (6) Pressing process Use a nylon curved pressing table to shape the curved surface of the plate, and then the enamel plate with the curved surface shape is obtained.

2. The production and processing method of a curved enamel plate according to claim 1, characterized in that, In step (1), for the press equipment, it is necessary to consider whether the size and pressure of the press can meet the stamping requirements; the 3D software is UG.

3. The production and processing method of a curved enamel panel according to claim 1, characterized in that, In step (2), the casting process uses the lost foam casting process. The specific process is as follows: After brushing and drying a foam model with the same size as the casting with refractory materials, it is buried in dry quartz sand, or perlite sand, or forsterite sand and vibration molded. Then, it is poured under negative pressure to vaporize the foam model, and the liquid metal occupies the position of the model and forms a casting after solidifying and cooling.

4. The production and processing method of a curved enamel panel according to claim 1, characterized in that, In step (3), in the product stamping production process, the raw material steel plate uses a zero-carbon steel plate with a thickness of 2 mm, and all are laser cut. After cutting, the burrs at the cutting edges and the iron filings on the plate surface are cleaned.

5. The production and processing method of a curved enamel panel according to claim 1, characterized in that, In step (3), it also includes: After the surface of the plate is formed into a curved surface, the data of the plate surface is scanned and compared with the digital model. The position with a large error on the plate surface is repaired and then stamped until the size of the plate surface meets the design requirements.

6. The production and processing method of a curved enamel plate according to claim 1, characterized in that, In step (5), the pickling is specifically as follows: The mixing ratio concentration, soaking time, cleaning solution temperature, drying temperature, and drying time are key controlled, and manual treatment is carried out on special positions of the slab. The spraying of the primer and topcoat is specifically as follows: Wet primer is sprayed on the reverse side, covering the whole surface, with a thickness of 70 - 100 μm and keeping it uniform, and the parameters of the spraying line are adjusted; Manual supplementary spraying is carried out on the weak spraying positions, and then it is checked whether there are static electricity sparks, powder flushing, powder spots, and powder dropping on the plate surface. The drying is specifically as follows: Before the drying conversion, the glaze accumulation at the acute angles of the inner holes is checked and cleaned, and the thickness of the primer on the reverse side is checked. The enameling firing is specifically as follows: The position of the hanging point for stress is adjusted, and the temperature is raised to above 800 °C to completely fuse the glaze powder and the steel plate substrate.

7. The production and processing method of a curved enamel panel according to claim 1, characterized in that In step (6), the nylon curved surface pressing table is specifically as follows: The original positive and negative curved surfaces of the plate are simulated to form a compression layer by bonding the back of the enamel plate, the aluminum honeycomb core, and the 2.0 mm aluminum back plate with epoxy glue, and then the fired enamel plate body is corrected by the upper pressing table and the lower pressing table with curved surfaces.

8. The production and processing method of a curved enamel plate according to claim 7, characterized in that, During the process of pressing the nylon curved surface, the sizing amount is 550 - 600 g / m 2 ; Clean the glue on the back of the aluminum plate, and the backing plate must be flat; Tighten the screw rod assembly with a torque wrench, and the pressure is 50 NM; The crimping temperature is 20 - 30 °C, and the time is more than 16 h.

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