JP2010094643A - Method of manufacturing metal catalyst carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a metal catalyst carrier, which can prevent a displacement of a brazing material to an outer cylinder in spite of a reception shape of a honeycomb body to the outer cylinder, and can prevent occurrences of defective products. <P>SOLUTION: The method of manufacturing the metal catalyst carrier 1 includes providing the honeycomb body 2 formed by multiply-winding while overlapping a waved metal foil 4 and a tabular metal foil 5, and the tubular outer cylinder 3 housing the honeycomb body 2, and joining the outer periphery of the honeycomb body 2 and the inner periphery of the outer cylinder 3 by melting the brazing material 7 provided between the outer periphery of the honeycomb body 2 and the inner periphery of the outer cylinder 3. The brazing material 7 is provided by a clad processing on the inner periphery of the outer cylinder 3. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a metal catalyst support.

Conventionally, a technique described in Patent Document 1 is known as a method for producing a metal catalyst carrier.
According to this invention, the position of the brazing material relative to the outer cylinder is determined from the appearance by forming a through-hole that is closed by the brazing material in the outer cylinder.
JP 2008-194552 A

However, the conventional invention has a problem that it is not possible to prevent displacement of the brazing material with respect to the outer cylinder.
In addition, since the brazing material formed in a foil shape is expensive, it leads to an increase in manufacturing cost.

  The present invention has been made to solve the above-mentioned problems, and the object of the present invention is to provide a metal catalyst capable of preventing the displacement of the brazing material with respect to the outer cylinder regardless of the accommodation form of the honeycomb body in the outer cylinder. It is to provide a method for producing a carrier.

  The invention according to claim 1 is provided with a honeycomb body formed by wrapping a corrugated metal foil and a flat or small corrugated metal foil in multiple layers, and a cylindrical outer tube for accommodating the honeycomb body, In the method for producing a metal catalyst carrier in which the outer peripheral part of the honeycomb body and the inner peripheral part of the outer cylinder are joined by melting of the brazing material provided between the outer peripheral part of the body and the inner peripheral part of the outer cylinder. Is provided by cladding the inner peripheral surface of the outer cylinder.

In the first aspect of the invention, the brazing material is clad on the inner peripheral surface of the outer cylinder.
Thereby, regardless of the accommodation form of the honeycomb body in the outer cylinder, it is possible to prevent the displacement of the brazing material with respect to the outer cylinder.

  Embodiments of the present invention will be described below with reference to the drawings.

Example 1 will be described below.
1 is a side sectional view of a metal catalyst carrier of Example 1, FIG. 2 is a view taken along arrow A1 of FIG. 1, FIG. 3 is a diagram for explaining the manufacture of the honeycomb body of Example 1, and FIG. FIG. 5 is a perspective view of the honeycomb body, and FIG.

  6 is a diagram for explaining the press-fitting device according to the first embodiment, FIG. 7 is a plan view of the press-fitting jig according to the first embodiment, FIG. 8 is a cross-sectional view taken along line S8-S8 in FIG. FIG. 14 is a diagram for explaining the exhaust system of the first embodiment.

First, the overall configuration will be described.
As shown in FIGS. 1 and 2, the metal catalyst carrier 1 of Example 1 includes a columnar honeycomb body 2 and a cylindrical outer cylinder 3 in which the honeycomb body 2 is accommodated.
Further, the outer periphery of the honeycomb body 2 and the inner periphery of the outer cylinder are brazed and joined over the entire periphery by the brazing material 7.
In addition, although the brazing material 7 of Example 1 is provided in the axial center position of the honeycomb body 2, this is not restrictive.

Next, a method for producing the metal catalyst carrier 1 will be described.
The metal catalyst carrier 1 is manufactured in the order of the honeycomb body forming process, the outer cylinder forming process, the press-fitting process, and the brazing process. The honeycomb body forming step and the outer cylinder forming step are performed in parallel.

[Honeycomb forming step]
In the honeycomb body forming step, the honeycomb body 2 is formed using a processing apparatus similar to that disclosed in JP-A-2006-239580.
That is, as shown in FIG. 3, first, the metal foil 5 is formed on the outer side of the starting end of the long and corrugated metal foil 4 made of roll gear or the like and the starting end of the long and flat metal foil 5. After being fixed to the winding shaft 6 so as to be, the two metal foils 4 and 5 are overlapped and wound into multiple rolls.
Thereafter, the end portions of the metal foils 4 and 5 are fixed to the outer peripheral portion by spot welding or the like to obtain the honeycomb body 2 (see FIG. 4).
The thicknesses of the metal foils 4 and 5 are each about 20 to 30 μm, and the material is made of a stainless alloy containing high-rigidity aluminum. Further, the metal foils 4 and 5 are annealed or loosely quenched so as to have high rigidity.
Specifically, for example, lanthanum (LA), which has a high effect of suppressing the growth of an Al ₂ O ₃ coating (alumina coating) generated by high-temperature oxidation based on chromium (Cr) or aluminum (Al), is added. Ferritic stainless steel with excellent high temperature oxidation is used.
Examples of ferritic stainless steel include JFE standard JFE20-5USR and JFE18-3USR.

[Outer cylinder forming process]
In the outer cylinder forming step, first, as shown in FIG. 5A, a brazing material 7 is clad and provided at a predetermined position on one side of a plate-like base material 8 that becomes the outer cylinder 3.
In addition, as a method of clad processing the brazing material 7 to the base material 8 that becomes the outer cylinder 3, first, the base material 8 and the brazing material 7 are temporarily overlapped and temporarily fixed in the same manner as in general clad processing. Heat to temperature and hot roll to clad bond.
Then, the desired preform | base_material 8 is obtained by performing cold rolling and rolling to predetermined thickness.

Alternatively, a powdered brazing material is applied to a predetermined position of the base material and rolled to a predetermined thickness, and then heated to a predetermined temperature to perform clad bonding.
The plate thickness and material of the outer cylinder 3 can be set as appropriate. Generally, the thickness of the outer cylinder 3 is around 1.5 mm, and the material is ferritic stainless steel containing aluminum or the like.
Similarly, the thickness and material of the brazing material 7 can be set as appropriate. In general, the thickness of the brazing material 7 is equivalent to that of the metal foils 4 and 5 (around 20 to 30 μm), and the material is a nickel-based brazing material.

  Thereafter, as shown in FIG. 5 (b), the desired outer cylinder 3 is formed by processing the brazing material 7 into a cylindrical shape so as to be inside and joining the edges 3a and 3b by welding. Form.

[Press-fit process]
In the press-fitting step, the honeycomb body 2 is accommodated in the outer cylinder 3 by using a press-fitting device 10 similar to that disclosed in JP-A-11-197518.

<Press-fit device>
First, the press-fitting device 10 will be described in detail.
In FIG. 6, a tower block 12 standing on a horizontal base 11 has a rail 13 extending in the vertical direction, and a lifting plate 14 is slidably engaged with the rail 13. Yes.

A piston rod 15a of an air or hydraulic cylinder 15 attached to the tower block 12 is connected to the elevating plate 14, and the elevating plate 14 can be moved up and down by the operation of the cylinder 15. .
Further, a support bracket 16 is provided at the upper part of the elevating plate 14, while a support bracket 17 is provided at the lower part.
A pneumatic or hydraulic cylinder 18 is mounted on the support bracket 16 in the vertical direction, and a cylindrical press-fitting jig 19 is mounted on the support bracket 17 coaxially with the piston rod 18a of the cylinder 18. ing.

A cylindrical press-fit block 20 is connected to the lower end of the piston rod 18a.
Note that the press-fit block 20 may be configured to be expandable / contractable in the radial direction in the same manner as that described in JP-A-2001-341034.

A work support block 21 coaxially disposed below the press-fitting jig 19 is fixed on the base 11, and the upper surface of the work support block 21 is fitted to the inner periphery of the lower end of the outer cylinder 3. An annular projection-like projection 21a is formed.
Further, a disk-shaped support body 22 is disposed coaxially below the press-fitting block 20.
A piston rod 23a of a pneumatic or hydraulic cylinder 23 accommodated in the base 11 through the press-fitting jig 19 and the work support block 21 is connected to the lower portion of the support body 22. The support 22 can be moved up and down by the operation of the cylinder 23.

As shown in FIGS. 7 and 8, the inner periphery of the press-fitting jig 19 has a first guide hole 19a having a tapered surface that opens while gradually increasing in diameter toward the lower end thereof, and the first guide hole 19a. A perfect circle correction hole 19b connected to the upper end, an annular step portion 19c standing from the upper end of the correction hole 19b, and the diameter gradually increases from the inner peripheral edge of the annular step portion 19c toward the upper end of the jig 19. On the other hand, a second guide hole 19d having a tapered surface that opens is formed.
The inlet diameter L1 at the upper end of the second guide hole 19c is larger than the outer diameter of the honeycomb body 2, while the outlet diameter L2 at the lower end is set smaller than the inner diameter of the outer cylinder 3.
The inlet diameter L3 at the lower end of the first guide hole 19a is larger than the outer diameter of the outer cylinder 3, and the inner diameter L4 of the correction hole 19b is set equal to the outer diameter of the outer cylinder 3.

<Operation of press-fitting device>
In the press-fitting device 10 configured as described above, first, the lifting plate 14 is stopped at the raised position by the contraction operation of the piston rod 15a of the cylinder 15.
Further, as shown in FIG. 9, the outer cylinder 3 is placed on the work support block 21 in a state where the support 22 is stopped at the same height as the protrusion 21a by the contraction operation of the piston rod 23a of the cylinder 23.
At this time, the outer cylinder 3 can be arranged coaxially with the press-fitting jig 19 by fitting the protrusion 21 a inside the lower end of the outer cylinder 3.

Next, as shown in FIGS. 9 and 10, the lifting plate 14 is gradually lowered by the extension operation of the piston rod 15 a of the air cylinder 15.
At this time, the upper end portion of the outer cylinder 3 on the work support block 21 is fitted into the correction hole 19b through the first guide hole 19a of the press-fitting jig 19, whereby the distortion of the outer cylinder 3 is corrected.
And the raising / lowering board 14 is stopped in the position where the upper end part of the outer cylinder 3 contact | abutted to the annular step part 19c.

  Next, as shown in FIG. 11, the support 22 is disposed slightly above the upper end of the press-fitting jig 19 by the extension operation of the piston rod 23 a of the cylinder 23, and then the honeycomb body is placed on the support 22. 2 is placed.

  Next, the press-fit block 20 coupled to the piston rod 18a is gradually lowered by the extension operation of the cylinder 18, and when the lower surface of the press-fit block 20 comes into contact with the upper surface of the honeycomb body 2, the piston rod 23a of the cylinder 23 The support 22 is lowered in synchronization with the press-fit block 20 by the contraction operation.

  Thereafter, as shown in FIG. 12, when the lower end of the honeycomb body 2 comes into contact with the inclined portion 19d of the press-fitting jig 19, the support body 22 is accelerated and returned to the original position (see FIG. 13).

On the other hand, as shown in FIG. 13, the press-fit block 20 pushes the upper surface of the honeycomb body 2 downward, and descends until the lower end of the press-fit block 20 is at the same height as the lower end of the guide portion 19 e or slightly below.
Thereby, the honeycomb body 2 can be press-fitted into the outer cylinder 3 and accommodated in a predetermined position.
The outer cylinder 3 in which the honeycomb body 2 is housed is moved to the work support block after the lifting plate 14 (press-fit jig 19) is returned to the original position by the contraction operation of the piston rods 15a and 18a of the cylinders 15 and 18. 21 can be removed.

<About prevention of damage to brazing material>
Here, when the brazing material is wound around the outer periphery of the honeycomb body, the strength of the end portion in the axial direction of the brazing material is particularly low when passing through the press-fitting jig, and this portion may be damaged.
The damage described above may occur during the process of winding the brazing material around the honeycomb body or during the process of transporting the honeycomb body wound with the brazing material.
In addition, in the honeycomb body press-fitting step, the brazing material may be greatly deformed due to stress in the axial direction and the radial direction together with the honeycomb body, and may be displaced or damaged.

  Therefore, there is a risk that the brazing material may be displaced or damaged regardless of the housing form of the honeycomb body. Therefore, as described in JP-A-2008-194552, the brazing material is displaced from the appearance of the outer cylinder. A process for judging is required.

On the other hand, in Example 1, as described above, the brazing material 7 is provided on the inner side of the outer cylinder 3 by cladding.
Therefore, the step of winding the thin brazing material around the outer peripheral portion of the honeycomb body can be omitted.
Further, since the brazing material 7 provided inside the outer cylinder 3 is not exposed to the outside, the brazing material 7 can be protected without any risk of being damaged when the outer cylinder 3 is conveyed.
Further, since there is no friction with the press-fitting jig 19 during the honeycomb body press-fitting step, the brazing material 7 is not deformed, and there is no possibility of occurrence of displacement or damage.
Therefore, in the first embodiment, the honeycomb body 2 can be accommodated in the outer cylinder 3 without causing the displacement and damage of the brazing material 7.
In addition, the production cost can be reduced by eliminating the use of an expensive brazing material formed in a foil shape.

[Brazing process]
The metal catalyst carrier 1 formed in this way is conveyed to a heating furnace in a state of being pressurized from the outer cylinder 3 and is heat-treated, so that the top of the wave of the metal foil 4 is in contact with the metal foil 5. Is diffusion bonded and the outer peripheral portion of the honeycomb body 2 and the inner peripheral portion of the outer cylinder 3 are brazed and joined by melting the brazing material 7.

  The metal catalyst carrier 1 taken out from the press-fitting device 10 is then exhausted from a noble metal, alumina or the like on the surface of the cell penetrating in the axial direction formed by the gap between the two metal foils 4 and 5 of the honeycomb body 2. A catalyst carrier layer for purification is formed.

[Connection to exhaust system]
The thus configured metal catalyst carrier 1 is interposed in a state in which both end portions of the outer cylinder 3 are connected in communication with an exhaust system of an internal combustion engine of an automobile.
For example, as shown in FIG. 14, an exhaust system of an internal combustion engine of an automobile has a metal catalyst carrier 1, a sub muffler a5, a main muffler a6 from exhaust ports (not shown) of an engine a1 on the exhaust upstream side through exhaust pipes a2 to a4. Are connected.
Further, one end portions of the corresponding cylindrical diffusers 24 and 24 are welded and fixed to both end portions of the outer cylinder 3 of the metal catalyst carrier 1.
Further, a connecting flange a7 for fastening to the corresponding connecting pipes a2 and a3 is welded and fixed to the other end portions of the diffusers 24 and 24 whose diameters are reduced.

Next, the operation will be described.
[Exhaust gas purification]
In the metal catalyst carrier 1 interposed in the internal combustion engine exhaust system of the automobile, the exhaust gas (shown by broken line arrows in FIG. 1) that flows into the outer cylinder 3 from one end of the outer cylinder 3 on the engine side exhaust upstream side is by passing through the cells of the honeycomb body 2, the other harmful components in the exhaust by the action of the catalyst (HC, CO, NOx, etc.) is purified into harmless components (CO 2, _H 2 _O, etc.) becomes the downstream side of exhaust gas It is discharged from the end toward the sub muffler a5 and the main muffler a6.

Next, effects of the first embodiment will be described together with (1) and (2) corresponding to claims 1 and 2.
(1) A honeycomb body 2 formed by wrapping a corrugated metal foil 4 and a flat metal foil 5 in a stacked state, and a cylindrical outer tube 3 for housing the honeycomb body 2 are provided. In the method of manufacturing the metal catalyst carrier 1 in which the outer peripheral part of the honeycomb body 2 and the inner peripheral part of the outer cylinder 3 are joined by melting of the brazing material 7 provided between the outer peripheral part and the inner peripheral part of the outer cylinder 3. The brazing material 7 was previously clad on one side of the material for the outer cylinder 3.
Thereby, irrespective of the accommodation form of the honeycomb body in the outer cylinder 3, the positional displacement of the brazing material 7 with respect to the outer cylinder 3 can be prevented, and the honeycomb body 2 can be securely brazed and joined to the outer cylinder 3.

(2) The honeycomb body 2 is press-fitted and accommodated in the outer cylinder 3.
Thereby, when the accommodation form of the honeycomb body 2 employs press-fitting into the outer cylinder 3, there is no possibility that the brazing material 7 is displaced with respect to the outer cylinder 3, which is preferable.

Example 2 will be described below.
In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, the description thereof will be omitted, and only the differences will be described in detail.

  FIG. 15 is a half sectional view of the metal catalyst carrier of Example 2.

As shown in FIG. 15, in the second embodiment, the bead portions 30 are formed on both sides in the longitudinal direction of the brazing material 7 so as to project outwardly over the entire circumference of the outer cylinder 3. Different from 1.
In addition, although the bead part 30 of Example 2 has a semicircular cross section projecting from the outer cylinder 3, the cross sectional shape of the bead part 30 can be set as appropriate.

Therefore, in the second embodiment, in addition to the operations and effects of the first embodiment, when a part of the brazing material 7 melted during the brazing process flows in the longitudinal direction of the honeycomb body 2, it flows into the bead portion 30. Can be made.
Thereby, since the honeycomb body 2 can be joined only at a desired position of the outer cylinder 3, the durability of the honeycomb body 2 can be improved.
More specifically, the honeycomb body repeats thermal expansion and expansion mainly in the axial direction due to exhaust heat, and when the brazing material joins the honeycomb body and the outer cylinder at irregular positions in the axial direction, the honeycomb body The honeycomb body is peeled off due to a large thermal stress generated during thermal expansion / contraction, and durability is lowered.
On the other hand, in Example 2, by flowing a part of the brazing material 7 into the bead portion 30, the flow in the longitudinal direction of a part of the brazing material 7 can be restricted and the joining range can be made appropriate.
Therefore, it is possible to minimize the generation of stress at the time of thermal expansion and expansion / contraction of the honeycomb body 2 and improve durability.

In addition, the shape (both capacity) of the bead part 30 is set according to the flow and the amount of a part of the brazing material 7 described above.
Further, the thickness and width of the brazing material 7 are set to values as small as possible while satisfying the necessary bonding strength condition between the honeycomb body 2 and the outer cylinder 3.

Although the embodiments have been described above, the present invention is not limited to the above-described embodiments, and design changes and the like within the scope not departing from the gist of the present invention are included in the present invention.
For example, in the first embodiment, the accommodation form in which the honeycomb body is accommodated by being press-fitted into the outer cylinder is taken as an example, but the present invention is not limited thereto.
That is, since the operation and effect of the present invention can be obtained regardless of the accommodation form of the honeycomb body in the outer cylinder, all metal catalyst carriers provided by cladding the brazing material on the outer cylinder fall within the scope of the present invention.

  The metal catalyst carrier of Example 1 has a circular cross section, but is not limited to this, and may have a cross section of another shape such as an elliptical shape, a triangular shape, or a racing track shape.

1 is a side sectional view of a metal catalyst carrier of Example 1. FIG. It is a figure by arrow A1 of FIG. 3 is a diagram for explaining the manufacture of a honeycomb body of Example 1. FIG. 1 is a perspective view of a honeycomb body of Example 1. FIG. It is a figure explaining manufacture of the outer cylinder of Example 1. FIG. It is a figure explaining the press injection apparatus of Example 1. FIG. 3 is a plan view of a press-fitting jig according to Embodiment 1. FIG. It is sectional drawing in the S8-S8 line | wire of FIG. It is a figure explaining the action | operation of the press injection apparatus of Example 1. FIG. It is a figure explaining the action | operation of the press injection apparatus of Example 1. FIG. It is a figure explaining the action | operation of the press injection apparatus of Example 1. FIG. It is a figure explaining the action | operation of the press injection apparatus of Example 1. FIG. It is a figure explaining the action | operation of the press injection apparatus of Example 1. FIG. It is a figure explaining the exhaust system of Example 1. FIG. 3 is a half sectional view of a metal catalyst carrier of Example 2. FIG.

Explanation of symbols

a1, a2, a3, a4 Exhaust pipe a5 Sub muffler a6 Main muffler a7 Connection flange X1 Welding 1 Metal catalyst carrier 2 Honeycomb body 3 Outer cylinders 3a, 3b (outer cylinder) both edges 4 Corrugated metal foil 5 Flat metal Foil 6 Winding shaft 7 Wax foil material 8 Base material 10 Press-fitting device 11 Base 11 Through hole 11a Reduced diameter side end 11b Expanded diameter side end 12 Tower block 13 Rail 14 Lift plate 15, 18, 23 Cylinder 15a, 18a, 23a Piston rods 16, 17 Support bracket 19 Press fitting jig 19a First guide hole 19b Correction hole 19c Annular step 19d Second guide hole 20 Press fit block 21 Work support block 21a Projection 22 Support body 24 Diffuser 30 Bead part

Claims (2)

A honeycomb body formed by multiply winding a corrugated metal foil and a flat or small corrugated metal foil;
A cylindrical outer cylinder that houses the honeycomb body,
In the method for producing a metal catalyst carrier in which the outer peripheral part of the honeycomb body and the inner peripheral part of the outer cylinder are joined by melting the brazing material provided between the outer peripheral part of the honeycomb body and the inner peripheral part of the outer cylinder,
A method for producing a metal catalyst carrier, wherein the brazing material is clad on the inner peripheral surface of an outer cylinder. In the manufacturing method of the metal catalyst carrier of Claim 1,
A method for manufacturing a metal catalyst carrier, wherein the honeycomb body is press-fitted and accommodated in the outer cylinder.

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