CN113414456A

CN113414456A - Asymmetric DPF mold and manufacturing method thereof

Info

Publication number: CN113414456A
Application number: CN202110867576.8A
Authority: CN
Inventors: 朱雪艳; 冯家迪
Original assignee: JIANGSU PROVINCE YIXING NONMETALLIC CHEMICAL MACHINERY FACTORY CO Ltd
Current assignee: JIANGSU PROVINCE YIXING NONMETALLIC CHEMICAL MACHINERY FACTORY CO Ltd
Priority date: 2021-07-23
Filing date: 2021-07-29
Publication date: 2021-09-21

Abstract

The application discloses an asymmetric DPF mold and a manufacturing method thereof, wherein the mold comprises an integral template, more than 2 uniformly distributed feeding holes are formed in the back surface of the integral template, more than 2 uniformly distributed discharge chutes are formed in the front surface of the integral template, and the discharge chutes are communicated with the corresponding feeding holes; wherein, more than 2 discharge chutes are composed of two types of tooth columns with different sizes. The mold adopts the rounded corners to design the groove face tooth columns, so that sharp corner interference is avoided, and the end face cracking defect of the product during sintering can be effectively improved; the mould adopts a split XY electrode to process the groove surface, the electrode processing equipment is more, the electrode material selection range is wide, the cost is low, the processing is more convenient, the efficiency is higher, the processing period is short, and the processing cost is lower. Narrow slit processing non-deformable etc. advantage, the inslot wall roughness can reach Ra1.0, satisfies the shaping and extrudes the requirement, has fine practicality.

Description

Asymmetric DPF mold and manufacturing method thereof

Technical Field

The invention belongs to the technical field of non-metallic ceramic materials, and particularly relates to a Diesel Particulate Filter (Diesel Particulate trap or Diesel Particulate trap regenerator) mold for Diesel vehicle six post-treatment and a manufacturing method thereof.

Background

A filter for post-treatment of carbon smoke particulate matters of diesel vehicles, which is a DPF honeycomb ceramic carrier with a symmetrical or asymmetrical structure, wherein a honeycomb ceramic die consists of a plurality of feeding holes and a discharging groove communicated with the feeding holes. In the CN105773091B patent application, the structural design and manufacturing method of the mold for the symmetric DPF honeycomb ceramic carrier are described, which can meet the requirements of the preparation and use of the DPF honeycomb ceramic carrier. In contrast, for the asymmetric DPF honeycomb ceramic carrier, since the product is composed of two types of holes with different sizes, a corresponding mold cannot be manufactured by a wire cutting method, and the existing mold cannot meet the manufacturing and using requirements of such products, so that a brand new mold for manufacturing the asymmetric DPF honeycomb ceramic carrier is urgently needed to be developed.

Disclosure of Invention

To not enough among the prior art, the technical problem that this application will solve provides an asymmetric DPF mould for make six aftertreatment soot particulate filters in diesel vehicle state. Another technical problem to be solved by the present application is to provide a method for manufacturing an asymmetric DPF mold.

In order to solve the technical problem, the technical scheme adopted by the application is as follows:

the asymmetric DPF die comprises an integral template, wherein more than 2 uniformly distributed feeding holes are formed in the back surface of the integral template, more than 2 uniformly distributed discharge chutes are formed in the front surface of the integral template, and the discharge chutes are communicated with the corresponding feeding holes; wherein, more than 2 discharge chutes are composed of two types of tooth columns with different sizes.

The discharge chute is a square tooth column with a round angle.

The tooth columns comprise large-size square tooth columns and small-size square tooth columns, wherein the fillet R range of the large-size square tooth columns is 0.16-0.25mm, and the fillet R range of the small-size square tooth columns is 0.09-0.15 mm.

The fillet R of the large-size square tooth column is 0.20mm, and the fillet R of the small-size square tooth column is 0.13 mm.

The preparation method of the asymmetric DPF mold adopts an electric discharge machining method to process the groove surface of the discharge groove.

In the preparation method of the asymmetric DPF die, the electrode adopted by the electric discharge machining is a split type electrode and consists of an X-direction electrode and a Y-direction electrode.

The X-direction electrode at least comprises an X-direction electrode unit, the X-direction electrode unit comprises an X-direction electrode main body extending in the X direction, and upward bulges and downward grooves are arranged on the X-direction electrode main body at intervals; the Y-direction electrode at least comprises a Y-direction electrode unit, the Y-direction electrode unit comprises a Y-direction electrode main body extending in the Y direction, and the Y-direction electrode main body is provided with a left bulge and a right bulge at intervals; when the electrode assembly is used, the X-direction electrode units are matched with the corresponding Y-direction electrode units, the adjacent upward protrusions and downward grooves and the adjacent leftward protrusions and rightward protrusions form end face shapes corresponding to the large-size square tooth columns and the small-size square tooth columns after the electrode assemblies are combined.

The preparation method of the asymmetric DPF mould comprises the following steps:

1) manufacturing a template blank by using die steel or other alloy steel;

2) programming a feeding hole drilling program, and then drilling a hole by a numerical control deep hole drill;

3) and manufacturing an electric machining electrode, programming an electric discharge machining program and machining the groove surface of the discharge groove.

According to the preparation method of the asymmetric DPF die, after the groove surface of the discharge groove is processed, the subsequent processing steps of deburring and coating are also carried out.

Has the advantages that: compared with the prior art, the mold groove face tooth column is provided with a round angle. And by adopting the fillet design, the interference of sharp corners is avoided, and the end surface cracking defect of the product during firing can be effectively improved. The utility model provides a mould adopts split type XY electrode machining groove face, and electrode machining can be with CNC processing, and the processing equipment is CNC processing equipment such as machining center. The electrode material has more selection range, and can be selected from conductive copper-tungsten alloy and other materials, and can also be selected from graphite and other electrode materials. The graphite electrode has the advantages of lower material cost, more convenient processing, higher efficiency, short processing period and lower processing cost. Narrow slit processing is not easy to deform, and the like. The roughness of the inner wall of the groove can reach Ra1.0, and the requirement of molding and extrusion is met.

Drawings

FIG. 1 is a schematic diagram of an asymmetric DPF product pore structure;

FIG. 2 is a schematic diagram of an asymmetric DPF mold structure;

FIG. 3 is a schematic view of an asymmetric DPF mold land and tooth post fillet;

FIG. 4 is a schematic diagram of an X-direction electrode structure of a split type asymmetric DPF die

FIG. 5 is a structural schematic diagram of a Y-direction electrode of a split type asymmetric DPF die;

FIG. 6 is a schematic view of an assembled asymmetric DPF electrode machining area.

Detailed Description

The present application is further described with reference to specific examples.

A diesel vehicle six post-treatment soot particulate filter is a DPF honeycomb ceramic carrier with an asymmetric structure. The product has a common hole density model of 300-9 and 300-7, a model of 300-9, namely 300 holes/square inch, a wall thickness of 9mil (0.229mm), a model of 300-7, namely 300 holes/square inch, and a wall thickness of 7mil (0.178 mm). The product is generally cylindrical, the diameter of the end face is in the range of 150-. The common diameter specification is 7.5 ' (190.5mm), 9 ' (228.6mm), 10.5 ' (266.7mm), 12 ' (304.8mm) and 13 ' (330.2mm), the product square holes are in asymmetric design, the length ratio of the sides of the square holes of the large holes and the small holes is 1.2-1.4, preferably 1.25-1.35, as shown in figure 1.

The main structure of the asymmetric DPF mould for preparing the DPF honeycomb ceramic carrier with the asymmetric structure is similar to that of a straight-through SCR (selective catalytic reduction) and DOC (diesel engine) honeycomb ceramic carrier mould. The structure is shown in figure 2, and is a whole template 1, and the back is processed and is had numerous evenly distributed feed port 2, and the front is processed numerous evenly distributed blown down tank 3, and blown down tank 3 and feed port 2 link up. The discharging groove 3 is composed of two types of tooth columns with different sizes, specifically a large-size square tooth column 4 and a small-size square tooth column 5, wherein the side length ratio of the large-size square tooth column 4 to the small-size square tooth column 5 is 1.2-1.4, and preferably 1.25-1.35. This application all is equipped with the fillet in the corner of the square tooth post of jumbo size 4 and the square tooth post of small-size 5, adopts the fillet design, has avoided the closed angle to interfere, also can effectively improve the terminal surface fracture defect when the product burns till. However, too large a radius results in a reduced through-hole area and increased back pressure. Therefore, a reasonable fillet range needs to be designed. Wherein, the fillet R of the large-size square tooth column ranges from 0.16 mm to 0.25mm, preferably 0.20mm, and the fillet R of the small-size square tooth column ranges from 0.09 mm to 0.15mm, preferably 0.13mm (figure 3).

The method for preparing the asymmetric DPF mould comprises the following steps:

1) manufacturing a template blank by using die steel or other alloy steel;

2) programming a feeding hole drilling program, and then drilling a hole by a numerical control deep hole drill; typical drilling procedures include one drilling process and two bottom hole cleaning processes; the primary drilling process comprises the following steps: drilling with a common gun drill, wherein the drilling depth is 0.3-0.5mm smaller than the final processing depth, and the bottom of the drilled hole is W-shaped; the twice bottom hole cleaning process comprises a first bottom hole cleaning process and a second bottom hole cleaning process, wherein the first bottom hole cleaning process is as follows: processing by using a first hole cleaning gun drill with special grinding, wherein the drilling depth is equal to the drilling depth, and removing the middle bulge of the W-shaped hole bottom; the second bottom hole cleaning process comprises the following steps: processing the hole bottom into a V shape by using a second hole cleaning gun drill with special grinding;

Different from a straight-through type honeycomb ceramic carrier mold, the asymmetric DPF mold has a groove surface with large and small holes. Namely, the tooth columns are distributed in a staggered way of large squares and small squares, as shown in fig. 3. The groove surface of the straight-through honeycomb ceramic carrier die can be processed by adopting methods such as linear cutting or grinding wheel cutting and the like. The asymmetric DPF die has the defects that the grooves are not in a straight line due to the distribution of large and small holes, and the methods such as linear cutting or grinding wheel cutting cannot be adopted. The method for processing the groove surface of the die generally adopts EDM (electrical discharge machining). EDM electrical discharge machining equipment is an electrical discharge machine such as Sadick, GF, etc. In the electric discharge machining, electric discharge is performed by an electrode, and the shape of a machined part is the same as that of the electrode. Electrical discharge machining, the electrode is critical. Different electrode materials and processing techniques have different influences on the processing quality, the processing cost and the processing efficiency of the die.

The electrode is usually machined by wire cutting to form a square hole and then discharge machining. The conventional integral electrode only can adopt red copper or copper-tungsten alloy, the material price is higher, wire cutting processing needs to process a plurality of wire penetrating holes in advance, and wire penetrating needs to be carried out again when one square hole is cut. The processing efficiency is very low. Moreover, the processing narrow gap of the red copper or the copper-tungsten alloy is easy to deform.

The application adopts an innovative XY two-direction split type electrode processing scheme. The specific electrodes are shown in fig. 4 and 5. The X-direction electrode at least comprises an X-direction electrode unit, the X-direction electrode unit comprises an X-direction electrode main body X1 extending in the X direction, and an upward protrusion X2 and a downward groove X3 are arranged on the X-direction electrode main body X1 at intervals; the Y-direction electrode at least comprises a Y-direction electrode unit, the Y-direction electrode unit comprises a Y-direction electrode main body Y1 extending in the Y direction, and a left protrusion Y2 and a right protrusion Y3 are arranged on the Y-direction electrode main body Y1 at intervals; when the X-direction electrode unit X1 is used, the X-direction electrode unit X1 is matched with the corresponding Y-direction electrode unit Y1, the adjacent upward protrusion X2 and downward groove X3 are combined with the adjacent leftward protrusion Y2 and rightward protrusion Y3, and the end face shapes corresponding to the large-size square tooth column and the small-size square tooth column are formed. In addition, a convex point X4 extending outward may be provided at a corner of the protrusion X2 and the downward groove X3.

By adopting the method, the electrode machining can be realized by CNC machining, and the machining equipment is CNC machining equipment such as a machining center and the like. The electrode material has more selection range, and can be selected from conductive copper-tungsten alloy and other materials, and can also be selected from graphite and other electrode materials. The graphite electrode has the advantages of lower material cost, more convenient processing, higher efficiency, short processing period and lower processing cost. Narrow slit processing is not easy to deform, and the like. The roughness of the inner wall of the groove can reach Ra1.0, and the requirement of molding and extrusion is met.

When the groove surface is specifically processed, as shown in fig. 6, the whole groove surface can be divided into 8 or more than 8 parts (divided into 1, 2, 3, 4, 5, 6, 7 and 8 regions) according to the X direction and the Y direction, and the groove surfaces are processed in the regions respectively and successively, so that the whole effect is finally formed.

After the groove surface of the discharge groove is processed, the discharge groove can be directly used for producing target products. In order to prolong the service life of the die and improve the quality of a target product, the subsequent processing steps such as surface coating and the like can be carried out on the die by adopting a conventional method.

Claims

1. The asymmetric DPF die is characterized by comprising an integral die plate (1), wherein more than 2 uniformly distributed feeding holes (2) are formed in the back surface of the integral die plate (1), more than 2 uniformly distributed discharge chutes (3) are formed in the front surface of the integral die plate (1), and the discharge chutes (3) are communicated with the corresponding feeding holes (2); wherein, more than 2 discharge chutes (3) are composed of two types of tooth columns with different sizes.

2. An asymmetric DPF mould as claimed in claim 1, wherein the discharge chute (3) is a square tooth column with rounded corners.

3. The asymmetric DPF mold as claimed in claim 2, wherein the teeth columns comprise large size square teeth columns (4) and small size square teeth columns (5), wherein the rounded corners R of the large size square teeth columns (4) range from 0.16 mm to 0.25mm, and the rounded corners R of the small size square teeth columns (5) range from 0.09 mm to 0.15 mm.

4. The asymmetric DPF mold as claimed in claim 3, wherein the rounded corner R of the large size square tooth column (4) is 0.20mm, and the rounded corner R of the small size square tooth column (5) is 0.13 mm.

5. The method for manufacturing an asymmetric DPF mold according to claim 1, wherein a groove surface of the discharge groove is processed by an electrical discharge machining method.

6. The method for preparing an asymmetric DPF mold according to claim 1, wherein an electrode used for the electric discharge machining is a split electrode consisting of an X-direction electrode and a Y-direction electrode.

7. The method for preparing an asymmetric DPF mold as defined in claim 6, wherein said X-direction electrode comprises at least one X-direction electrode unit, said X-direction electrode unit comprises an electrode body (X1) extending in X-direction, and an upward protrusion (X2) and a downward groove (X3) are provided at intervals on the electrode body (X1); the Y-direction electrode at least comprises a Y-direction electrode unit, the Y-direction electrode unit comprises a Y-direction electrode main body (Y1) extending in the Y direction, and a left protrusion (Y2) and a right protrusion (Y3) are arranged on the Y-direction electrode main body (Y1) at intervals; when the electrode unit is used, the X-direction electrode unit is matched with the corresponding Y-direction electrode unit, and the adjacent upward protrusion (X2) and downward groove (X3) and the adjacent leftward protrusion (Y2) and rightward protrusion (Y3) are combined to form the end surface shape corresponding to the large-size square tooth column (4) and the small-size square tooth column (5).

8. The method for preparing an asymmetric DPF mold according to claim 1, comprising the steps of:

1) manufacturing a template blank by using die steel or other alloy steel;

9. The method for preparing an asymmetric DPF mold as recited in claim 1, wherein after the groove surface of the discharge groove is machined, the subsequent machining steps of deburring and coating are further performed.