Double-hole density honeycomb ceramic mold and manufacturing method thereof

Abstract

The invention discloses a double-hole-density honeycomb ceramic mold and a manufacturing method thereof, and belongs to the technical field of honeycomb ceramic molds. The method comprises the steps that firstly, alloy die steel is machined into a plurality of round die blanks, a feeding hole with the needed hole diameter is machined in one side of each round die blank, a tooth table is machined on the other side of each round die blank, and deep hole die blanks with the tooth tables and different hole diameters are obtained; a discharging groove and a feeding hole of a deep-hole mold blank body with a tooth table are communicated and then assembled, and the double-hole density honeycomb ceramic mold is obtained by debugging until mold mud discharging is uniform and smooth and grids have no broken line defect. Compared with a conventional single-pore-density honeycomb ceramic carrier, the double-pore-density honeycomb ceramic carrier manufactured by the method has the advantages that the content of precious metal needing to be coated is reduced, and the production cost can be obviously reduced under the condition that the catalytic reaction requirement can also be met.

Description

Technical Field

[0001] The invention belongs to the technical field of honeycomb ceramic moulds, and in particular relates to a double-hole density honeycomb ceramic mould and a manufacturing method thereof. Background Art

[0002] In practical applications, since most of the exhaust gas containing harmful substances flows out from the middle area, the exhaust gas purification requirement can be achieved as long as the normal load of the catalyst in the middle area is guaranteed. However, the existing single-pore density honeycomb ceramic carrier has a single pore density. In order to ensure the catalytic effect, it can only use a single higher pore density, a higher specific surface area, and a larger amount of catalyst coating, which is not conducive to reducing the production cost of the process and has low economic benefits.

[0003] Based on this, how to prepare a honeycomb ceramic mold product with two pore densities to obtain a honeycomb ceramic carrier with two different pore densities in the middle area and the peripheral area, which can effectively purify the exhaust gas when used in the field of motor vehicle exhaust purification, while reducing the amount of catalyst coating and reducing the process cost has become a problem that needs to be solved at present. Summary of the invention

[0004] The first purpose of the present invention is to disclose a method for manufacturing a double-hole density honeycomb ceramic mold, which includes first processing two separate single-density molds separately, and then combining the two separate single-density molds to obtain a double-hole density honeycomb ceramic mold with good bonding performance and precise matching.

[0005] The second object of the present invention is to provide a dual-pore density honeycomb ceramic mold, which can produce a dual-pore density straight-through honeycomb ceramic carrier, and can coat catalysts in two pore density areas respectively to meet the catalytic reaction requirements in special fields.

[0006] In order to solve the above problems, the technical solution adopted by the present invention is as follows:

[0007] A method for manufacturing a double-hole density honeycomb ceramic mold comprises the following steps: firstly processing alloy mold steel into a plurality of circular mold blanks, processing a feed hole with a required aperture and depth on one side of each circular mold blank, and processing a gear stage on the other side of the circular mold blank to obtain a deep-hole mold blank with a gear stage and different apertures; assembling the deep-hole mold blank with the gear stage after the discharge trough is connected to the feed hole, and debugging the mold until the mud discharge is uniform and smooth and the grid has no broken wire defects to obtain the double-hole density honeycomb ceramic mold.

[0008] Furthermore, the alloy die steel is processed by turning and surface grinding to obtain a circular die blank.

[0009] Furthermore, one side of a portion of the circular mold blank is processed by CNC machining to form a feed hole with a 600-mesh middle area and a 400-mesh peripheral area; one side of another portion of the circular mold blank is processed by CNC machining to form a feed hole with a 400-mesh mesh.

[0010] Furthermore, the discharge groove of the mold blank is connected to the feed hole by means of electric spark wire cutting.

[0011] Furthermore, the assembly method is: two separate mold blanks are matched in position with positioning pins, and then fastened with screws.

[0012] Furthermore, the manufacturing method of any of the above-mentioned double-pore density honeycomb ceramic molds comprises the following steps:

[0013] Step 1: Select alloy die steel and manufacture circular die 1 blank and circular die 2 blank through turning and surface grinding processes;

[0014] Step 2: CNC machining is used to process a feed hole with a mesh size of 600 in the middle area and a mesh size of 400 in the peripheral area on one side of the blank of the circular mold 1, and then a feed hole with a mesh size of 400 is processed on one side of the blank of the circular mold 2;

[0015] Step 3: machining a gear table on the other side of the circular mold 1 blank and the other side of the circular mold 2 blank by turning to obtain a deep hole mold blank with a gear table;

[0016] Step 4: Clean and dry the deep hole mold blank with a gear table obtained in step 3;

[0017] Step 5: Connect the discharge trough to the feed hole through the wire EDM process;

[0018] Step 6: Cut a square hole or a round hole in the middle area of ​​the circular mold 2 by wire cutting, so as to be put on the circular mold 1 when it is assembled with the circular mold 1 later;

[0019] Step 7: Clean and debug the processed mold, and finally clean the processed double-hole density honeycomb ceramic mold to obtain a single-density mold;

[0020] Step 8: Use positioning pins to align the positions of two separate single-density molds, and then tighten them with screws to combine the two single-density molds together to obtain a double-hole density honeycomb ceramic mold blank; prepare the mold sleeve, install it on the molding press to debug the mold until the mold discharges mud evenly and smoothly, and the grid has no broken wire defects, and the double-hole density honeycomb ceramic mold is obtained.

[0021] Furthermore, in step 1, the diameter of the circular mold 1 blank and the circular mold 2 blank are 100-200 mm and the height is 20-40 mm.

[0022] Furthermore, in step 3, the gear stage height is 4-5 mm, and the mold gear stage protrudes from the feed bottom hole by 0.6-1.0 mm.

[0023] Furthermore, a double-pore density honeycomb ceramic mold is manufactured by any of the above methods.

[0024] Furthermore, the honeycomb ceramic carrier obtained by the double-pore density honeycomb ceramic mold has two pore densities, the pore density of the middle area is 600 meshes, and the pore density of the edge area is 400 meshes; the middle area is square or circular.

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] 1) The present invention can manufacture a straight-through honeycomb ceramic carrier with double pore density. In one honeycomb ceramic carrier, there are two pore sizes and pore densities, the middle area has a higher pore density, and the peripheral area has a lower pore density.

[0027] 2) Compared with conventional single-pore density carriers, the double-pore density carrier of the present invention requires less precious metal coating, which reduces production costs while still meeting the requirements of the catalytic reaction. Since most of the exhaust gas flows out from the middle area, as long as the middle area is 600 mesh, the edge area 400 mesh can meet the exhaust gas purification requirements. The edge area 400 mesh has a smaller specific surface area than 600 mesh, and the specific surface area of ​​the double-pore density carrier is smaller than that of the single-pore density carrier. Therefore, less precious metal is required for coating, which reduces production costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a cross-sectional view of a double-pore density honeycomb ceramic product with a square center according to the present invention;

[0029] Figure 2 It is a cross-sectional view of a double-pore density honeycomb ceramic product with a circular center according to the present invention;

[0030] Figure 3 A top view of a double-hole density honeycomb ceramic mold with the positioning pins of the present invention determining the matching position;

[0031] Figure 4 This is a cross-sectional view of a single-pore density honeycomb ceramic product;

[0032] Figure 5It is a front cross-sectional view of the side structure of the double-hole density honeycomb ceramic mold of the present invention; wherein, 1, forming discharge trough 1; 2, forming discharge trough 2; 3, feed hole 2; 4, mold body 2; 5, positioning pin; 6, adjustment ring; 7, mold body 1; 8, feed hole 1-2; 9, feed hole 1-1;

[0033] Figure 6 It is the main cross-sectional view of the side structure of a single-hole density honeycomb ceramic mold; wherein A is the forming discharge trough; B is the feed hole; and C is the mold body. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with specific embodiments.

[0035] Unless otherwise specified, the materials and instruments involved in the following examples are all commercially available products or products prepared by conventional methods.

[0036] Example 1

[0037] A double-hole density honeycomb ceramic mold comprises a single-hole density mold a, a single-hole density mold b and an adjustment ring 6 located between the single-hole density mold a and the single-hole density mold b; the single-hole density mold a, the single-hole density mold b and the adjustment ring 6 are determined by four positioning pins to ensure the position accuracy of the two molds and the adjustment ring 6, and are fastened by two screws, and the adjustment ring 6 is pressed between the two molds, such as Figure 3 shown.

[0038] like Figure 5 As shown in the figure, the feed holes of the single hole density mold a are divided into two areas with two hole densities (i.e., feed holes 1-1 9 and feed holes 1-2 8). The middle area has a larger hole density, between 600 mesh and 750 mesh. The peripheral area is arranged according to the feed holes of the single hole density mold b (i.e., feed holes 2 3), and the middle area is arranged in a jump grid, with a hole diameter of 0.9~1.2 mm. The final tooth table thickness of the single hole density mold a is the sum of the total thickness of the single hole density mold b and the thickness of the adjustment ring 6. The middle area is square or round, such as Figure 1 and Figure 2 shown.

[0039] The hole density of single hole density mold b is a relatively small hole density, between 400 and 600 meshes, the feed holes are distributed in a jump grid, and the hole diameter is 1.4~1.1 mm.

[0040] The adjusting ring 6 is used to adjust the difference in extrusion flow rate between the middle and edge regions due to the different hole densities.

[0041] Example 2

[0042] A method for manufacturing a double-pore density honeycomb ceramic mold comprises the following steps:

[0043] (1) Selecting alloy mold steel to prepare circular mold 1 blank and circular mold 2 blank through turning and surface grinding processes; specifically: according to the actual size of the mold to be processed, using high-quality mold steel blanks on a lathe or grinder to make circular mold blanks with a diameter of 100-200 mm and a height of 20-40 mm;

[0044] (2) CNC machining is used to process feed holes with 600 mesh in the middle area and 400 mesh in the peripheral area on one side of the blank of circular mold 1, and then a 400 mesh feed hole is processed on one side of the blank of circular mold 2; specifically: according to the mesh number, diameter and raw material shrinkage rate of the mold to be processed, programming is performed on the horizontal CNC deep hole drilling machine to set the drilling range, the hole spacing of the evenly distributed mold feed holes, the drilling depth, the feed speed, the time and other programs. The circular mold blank is fixed on the horizontal CNC deep hole drilling reference plane for drilling, and then a hollow long-shank alloy steel gun drill with a suitable diameter is selected for drilling according to the mesh number and mud feed amount of the product. Hole drilling with a hollow long-shank alloy steel gun drill is better than the twist drill drilling process. It is an extrusion drilling process, and the roughness of the inner wall of the hole is much lower than that of the twist drill drilling. No polishing is required after drilling. When the gun drill is drilling, cooling and lubricating oil flows out from the center, which reduces the temperature generated by drilling. At the same time, the flowing oil can take away the broken slag and iron chips generated by drilling. It can be fed in one time and the hole is processed deeply. There is no need to frequently retract the tool to remove chips like the chicken pecking rice method of twist drill drilling, which ensures the accuracy and efficiency of drilling.

[0045] (3) A gear table is machined on the circular mold 1 blank and the circular mold 2 blank by turning to obtain a deep hole mold blank with a gear table; the mold gear table is machined on a CNC lathe according to the punching range (d) and the mold tooth height (h) on the mud discharge surface of the circular mold blank. The gear table height is 4-5 mm, and the mold gear table height exceeds the feed bottom hole by 0.6-1.0 mm to obtain a deep hole mold blank with a gear table;

[0046] (4) Cleaning and drying the deep hole mold blank with a gear table obtained in step (3);

[0047] (5) Processing the discharge trough through wire electrospark cutting until it is connected to the feed hole;

[0048] (6) Clean and debug the processed mold, and finally clean the processed double-hole density honeycomb ceramic mold (generally soak it in gasoline for 24 hours to remove oil stains, and then rinse it with a high-pressure water gun).

[0049] (7) Use four locating pins to align the two separate single-density molds, and then fasten them with two hexagon socket screws to combine the two single-density molds together. Achieve precise positioning and fix them together without moving. The locating pin holes are drilled at the same time as the feed holes, without secondary calibration and positioning, ensuring the position accuracy. After combination, a double-hole density honeycomb ceramic mold blank is obtained.

[0050] The mold sleeve is prepared and installed on a molding press to debug the mold until the mold discharges mud evenly and smoothly and the grid has no broken wire defects, thus obtaining a double-hole density honeycomb ceramic mold that can be used for production operations.

[0051] The double-pore density honeycomb ceramic mold produced by the present invention is a straight-through honeycomb ceramic carrier mold, which can manufacture a double-pore density straight-through honeycomb ceramic carrier, which is used for motor vehicle exhaust purification after being coated with a catalyst. The manufactured carrier is a three-way catalyst carrier, which converts harmful gases such as carbon monoxide, hydrocarbons and nitrogen oxides in automobile exhaust into harmless carbon dioxide and water through oxidation and reduction reactions. Compared with conventional single-pore density carriers, the double-pore density carrier needs to reduce the content of precious metals to be coated, and the production cost can be significantly reduced when the catalytic reaction requirements can be met. Since most of the exhaust gas flow containing harmful substances flows out from the middle area, as long as the middle area is 600 mesh, the edge area 400 mesh can achieve the exhaust gas purification requirements. The edge area 400 mesh has a smaller specific surface area than 600 mesh, and the specific surface area of ​​the double-pore density carrier is smaller than that of the single-pore density carrier, so the content of precious metals coated is less, which is conducive to reducing the cost of the entire process.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a double-pore density honeycomb ceramic mold, characterized in that: First, the alloy mold steel is processed into several circular mold blanks, a feed hole with the required aperture and depth is processed on one side of each circular mold blank, and a gear table is processed on the other side of the circular mold blank to obtain a deep-hole mold blank with a gear table and different apertures; the discharge chute of the deep-hole mold blank with a gear table is connected to the feed hole and then assembled, and the double-hole density honeycomb ceramic mold is obtained by debugging until the mold discharges mud evenly and smoothly and the grid has no broken wire defects.

2. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 1, characterized in that: The alloy die steel is turned and surface ground to obtain a circular die blank.

3. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 1, characterized in that: One side of a portion of the circular mold blank is processed by CNC machining to form a feed hole with a 600-mesh middle area and a 400-mesh peripheral area; one side of another portion of the circular mold blank is processed by CNC machining to form a feed hole with a 400-mesh.

4. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 1, characterized in that: The discharge groove and the feed hole of the mold blank are connected by electric spark wire cutting processing.

5. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 1, characterized in that: The assembly method is: two separate mold blanks are matched in position with positioning pins and then fastened with screws.

6. The method for manufacturing a double-pore density honeycomb ceramic mold according to any one of claims 1 to 5, characterized in that: Here are the steps: Step 1: Select alloy die steel and manufacture circular die 1 blank and circular die 2 blank through turning and surface grinding processes; Step 2: CNC machining is used to process a feed hole with a mesh size of 600 in the middle area and a mesh size of 400 in the peripheral area on one side of the blank of the circular mold 1, and then a feed hole with a mesh size of 400 is processed on one side of the blank of the circular mold 2; Step 3: machining a gear table on the other side of the circular mold 1 blank and the other side of the circular mold 2 blank by turning to obtain a deep hole mold blank with a gear table; Step 4: Clean and dry the deep hole mold blank with a gear table obtained in step 3; Step 5: Connect the discharge trough to the feed hole through the wire EDM process; Step 6: Cut a square hole or a round hole in the middle area of ​​the circular mold 2 by wire cutting, so as to be put on the circular mold 1 when it is assembled with the circular mold 1 later; Step 7: Clean and debug the processed mold, and finally clean the processed double-hole density honeycomb ceramic mold to obtain a single-density mold; Step 8: Use positioning pins to align the positions of two separate single-density molds, and then tighten them with screws to combine the two single-density molds together to obtain a double-hole density honeycomb ceramic mold blank; prepare the mold sleeve, install it on the molding press to debug the mold until the mold discharges mud evenly and smoothly, and the grid has no broken wire defects, and the double-hole density honeycomb ceramic mold is obtained.

7. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 6, characterized in that: In step 1, the diameter of the circular mold 1 blank and the circular mold 2 blank are 100-200 mm and the height is 20-40 mm.

8. The method for manufacturing a double-pore density honeycomb ceramic mold according to claim 6, characterized in that: In step 3, the gear stage height is 4~5mm, and the mold gear stage exceeds the feed bottom hole by 0.6~1.0mm.

9. A double-pore density honeycomb ceramic mold manufactured according to any one of claims 1 to 8.

10. The double-pore density honeycomb ceramic mold according to claim 9, characterized in that: The honeycomb ceramic carrier obtained by the double-pore density honeycomb ceramic mold has two pore densities, the pore density of the middle area is 600 meshes, and the pore density of the edge area is 400 meshes; the middle area is square or circular.

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