JP2007237653A - Manufacturing method for ceramic honeycomb structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a ceramic honeycomb structure, which can restrain cell deformation from occurring on the outer peripheral part of the ceramic honeycomb structure. <P>SOLUTION: In this manufacturing method for the ceramic honeycomb structure, a mixture containing a ceramic material, an organic binder and water is charged into a vacuum kneading machine; a cylindrical body is formed by the vacuum kneading machine, and charged into a plunger type extruder; and a ceramic honeycomb molding is extruded by the plunger type extruder, and burnt to be turned into the ceramic honeycomb structure. A partial temperature difference of the cylindrical body charged into the plunger type extruder is set at 5°C or lower. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a ceramic honeycomb structure, and more particularly to a method for manufacturing a ceramic honeycomb structure capable of suppressing cell deformation occurring in the outer peripheral portion of the ceramic honeycomb structure.

  In order to collect dust and other particulate matter contained in incineration exhaust gas generated during incineration of automobile exhaust gas and waste, and further, NOx, CO and HC, etc. in the exhaust gas are supported by a supported catalyst. In order to remove impurities such as suspended matter, bacteria, and dust mixed in fluids (liquids and gases) in a wide range of fields such as water treatment and medicine / food in recent years. Furthermore, a ceramic honeycomb structure using a ceramic porous body as a filter medium is used. Such a ceramic honeycomb structure is usually manufactured by extruding a kneaded material containing ceramics or the like into a honeycomb shape to obtain a ceramic honeycomb formed body, and then firing the honeycomb formed body. Examples of the method for extruding the ceramic honeycomb formed body include methods such as plunger-type extrusion molding and continuous extrusion molding. Among these forming methods, a plunger type extrusion forming method is suitably used for manufacturing a ceramic honeycomb structure having a large size.

As a method for producing a ceramic honeycomb structure using a plunger-type extrusion molding method, for example, a raw material containing a ceramic raw material, an organic binder and water was kneaded with a kneader to form a kneaded product. The kneaded product is made into a cylindrical clay with a vacuum kneader, the obtained cylindrical clay is charged into a plunger-type extruder, the ceramic honeycomb molded body is extruded, and the resulting ceramic honeycomb molded body is obtained. Can be mentioned as a ceramic honeycomb structure (see, for example, Patent Document 1). However, such a conventional method has a problem that a partial cell of the ceramic honeycomb structure is deformed.
JP 2002-326879 A

  In the method for manufacturing the ceramic honeycomb structure, a temperature difference is partially caused in the kneaded product and the formed cylindrical clay by friction between the raw material and the apparatus metal part during the kneading and the formation of the cylindrical clay. When the product is pushed out, there is a problem that the extrusion speed of the clay is varied, and the cell is deformed (particularly, the outer peripheral portion of the product) in the final product. Therefore, in order to suppress the temperature rise at the time of kneading, kneading is performed while cooling the inside of the tank of the kneading machine with a refrigerant. Next, when forming a cylindrical clay from the obtained kneaded material with a vacuum kneader, the vacuum kneader was cooled with a refrigerant to suppress an increase in temperature during the extrusion of the cylindrical clay. Then, the obtained cylindrical clay was put into a plunger (material) tube of a plunger type molding machine, and a ceramic honeycomb structure was extruded.

  However, when only cooling is performed at the time of kneading and forming the cylindrical clay in this way, the partial temperature difference of the cylindrical clay increases, so that the partial cell deformation of the ceramic honeycomb structure is sufficiently achieved. I couldn't suppress it.

  The present invention has been made in view of the above problems, and provides a method for manufacturing a ceramic honeycomb structure capable of suppressing cell deformation of the ceramic honeycomb structure, particularly partial cell deformation. And

  In order to achieve the above object, the present invention provides the following method for manufacturing a ceramic honeycomb structure.

[1] A kneaded material containing a ceramic raw material, an organic binder and water is charged into a vacuum kneader, and a cylindrical clay is formed by the vacuum kneader. A method for manufacturing a ceramic honeycomb structure, comprising charging a molding machine, extruding a ceramic honeycomb molded body with the plunger-type extruder, and firing the ceramic honeycomb molded body to form a ceramic honeycomb structure. A method for manufacturing a ceramic honeycomb structure, wherein a partial temperature difference of the cylindrical clay charged in the plunger type extruder is 5 ° C. or less.

[2] The method for manufacturing a ceramic honeycomb structure according to [1], wherein an average temperature of the cylindrical clay charged in the plunger-type extruder is 5 to 20 ° C.

[3] After the cylindrical clay is formed by the vacuum kneader, the obtained cylindrical clay is held in a container or a constant temperature room at a constant temperature, and a partial temperature difference of the cylindrical clay is determined. The method for manufacturing a ceramic honeycomb structure according to [1] or [2], wherein after the temperature is set to 5 ° C. or less, the cylindrical clay is charged into a plunger-type extruder.

[4] The temperature of the inner surface of the plunger tube of the plunger-type extruder is 5 ° C. or higher, and is within a range of ± 5 ° C. relative to the average temperature of the cylindrical clay [2] or The method for producing a ceramic honeycomb structure according to [3].

[5] The method for manufacturing a ceramic honeycomb structure according to any one of [1] to [4], wherein the plunger-type extruder can control the temperature of the inner surface of the plunger tube.

[6] The ceramic honeycomb structure thus obtained is a columnar structure having an axial length of 500 to 2000 mm and a cross-sectional area of 700 to 70000 mm ² perpendicular to the axial direction. A method for manufacturing a ceramic honeycomb structure.

  According to the method for manufacturing a ceramic honeycomb structure of the present invention, since the partial temperature difference of the cylindrical clay charged in the plunger type extruder is 5 ° C. or less, the partial cell of the ceramic honeycomb structure Deformation can be suppressed.

  BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the best mode for carrying out the present invention will be specifically described. However, the present invention is not limited to the following embodiment, and is within the scope of the present invention without departing from the spirit of the present invention. It should be understood that design changes, improvements, and the like can be made as appropriate based on the knowledge.

  The method for producing a ceramic honeycomb structure of the present invention is obtained by charging a kneaded material containing a ceramic raw material, an organic binder and water into a vacuum kneader and forming a cylindrical clay with the vacuum kneader. The cylinder-shaped clay was charged into a plunger-type extruder, the ceramic honeycomb formed body was extruded using a plunger-type extruder, and the resulting ceramic honeycomb formed body was fired to obtain a ceramic honeycomb structure. The partial temperature difference of the cylindrical clay charged in the plunger type extruder is set to 5 ° C. or less. Thus, when the temperature difference between the inside and the surface of the cylindrical clay charged in the plunger type extruder is 5 ° C. or less, the cylinder type The partial extrusion speed of the soil becomes substantially the same, and partial cell deformation of the ceramic honeycomb structure can be suppressed. When this temperature difference is larger than 5 ° C., since the extrusion speed of the cylindrical clay is partially different in the plunger tube of the plunger type extruder, cell deformation of the ceramic honeycomb structure is caused. In particular, a temperature difference between the outer peripheral portion and the central portion of the cylindrical clay is likely to occur, and cell deformation tends to occur on the outer peripheral portion. The temperature of the cylinder-shaped clay is divided into 8 parts radially from the center at the center part in the length direction and the part entering the center part by the radius of the cross section from both ends in the length direction, and the diameter is further divided. The temperature of the part divided into three in the direction and the temperature of the outer peripheral part divided into eight parts are measured (in FIG. 3, the temperature measurement point 5 of the cylindrical clay 4 is indicated by “◯”). FIG. 3 shows a cross section of the central portion in the length direction, and the same applies to the cross section of the portion entering the central portion by the radius of the cross section from both ends in the length direction. Here, the “cross section” is a cross section perpendicular to the length direction. As shown in FIG. 3, the temperature of the portion equally divided into three in the radial direction is measured when the diameter of the cross section of the cylindrical clay is 100 mm or more. When the diameter is smaller than 100 mm, as shown in FIG. 4, the temperature of each part is measured by dividing into two in the radial direction (see FIG. "). The partial temperature difference of the cylindrical clay is a value obtained by subtracting the minimum temperature from the maximum temperature of a predetermined measured temperature. Hereinafter, an embodiment of the present invention will be described in detail for each process.

(1) Production of cylindrical clay:
(1-1) Preparation of kneaded material;
In one embodiment of the method for producing a ceramic honeycomb structure of the present invention, first, a kneaded material containing a ceramic raw material, an organic binder and water is charged into a vacuum clay kneader, and the cylinder-shaped clay is obtained by the vacuum kneader. Form.

  A kneaded material containing a ceramic raw material, an organic binder and water can be prepared by charging these raw materials into a kneader 1 shown in FIG. 1, mixing and kneading. As a ceramic raw material to be contained in the kneaded material, a material that is a raw material of the ceramic honeycomb structure to be produced is used with a predetermined composition. For example, cordierite, mullite, alumina, selben, silicon carbide, silicon nitride, or a mixture thereof can be used. Here, FIG. 1 is a schematic view showing a step of producing a cylindrical clay in the method for manufacturing a ceramic honeycomb structure of the present invention.

  The organic binder contained in the kneaded material is an additive that functions as a reinforcing agent that becomes a gel in the molded body before firing and maintains the mechanical strength of the molded body. Therefore, as the organic binder, an organic polymer that can be gelled in the molded body, for example, hydroxypropylmethylcellulose, methylcellulose, hydroxyethylcellulose, carboxymethylcellulose, polyvinyl alcohol and the like can be suitably used.

  In addition to the ceramic raw material, the organic binder, and water, the above-mentioned kneaded material may contain other additives such as a dispersant, an inorganic binder, and the like as necessary.

  The dispersant is an additive for promoting dispersion of the ceramic raw material in water, which is a dispersion medium. As the dispersant, for example, ethylene glycol, dextrin, fatty acid soap, polyalcohol and the like can be used.

  The inorganic binder is an additive for reinforcing the bond between ceramic raw materials, and is at least selected from the group consisting of alumina, silica, zirconia, titania, glass frit, feldspar, and cordierite having an average particle diameter of 10 μm or less. One can be used. In addition, although an inorganic binder is a particle | grains which consist of ceramics, it shall not be included in the ceramic raw material said to this invention.

  The inorganic binder is preferably added in an amount of 10 to 35 parts by mass with respect to 100 parts by mass of the ceramic raw material. If the amount is less than 10 parts by mass, the strength of the substrate may be reduced. If the amount exceeds 35 parts by mass, the strength is improved, but the inorganic binder remains in the gap between the ceramic raw materials. May reduce fluid permeation.

(1-2) Production of cylindrical clay;
Next, as shown in FIG. 1, the kneaded material 2 obtained as described above is charged into a vacuum kneader 3, and a cylindrical clay 4 is extruded by the vacuum kneader 3. The average temperature of the obtained cylindrical clay is preferably 5 to 25 ° C. By setting it as such a range, it becomes easy to adjust the temperature of the cylindrical clay before inserting into a plunger type extruder. The vacuum kneader 3 is provided with a jacket (not shown) and a cooling pipe (not shown), and a refrigerant is allowed to flow there, whereby the average temperature of the cylindrical clay can be controlled. preferable. Here, the average temperature of the cylindrical clay refers to the average value of the measured temperatures of the portion shown in FIG. 3 of the cylindrical clay.

  The shape of the obtained cylindrical clay 4 is preferably a columnar shape, and the size is preferably 100 mmφ × 500 mmL to 300 mmφ × 1500 mmL. When producing a ceramic honeycomb structure by producing a cylindrical clay of this size range, partial deformation of the ceramic honeycomb structure is likely to occur, so this range is the range of the ceramic honeycomb structure of the present invention. This is the range where the effects of the manufacturing method are most exhibited.

(2) Thermal insulation of cylindrical clay:
After forming the cylindrical clay with a vacuum kneader, it is preferable to hold the obtained cylindrical clay in a constant temperature container or a constant temperature room. And it can carry out easily that the partial temperature difference of a cylindrical clay is 5 degrees C or less by hold | maintaining and keeping a cylindrical clay in the container or constant temperature room of a fixed temperature. Thereby, it becomes possible to insert the cylindrical clay having a partial temperature difference of 5 ° C. or less into the plunger type extruder.

  Also, if the average temperature of the cylindrical clay is low, when the ceramic honeycomb formed body is formed and then dried, drying shrinkage tends to increase and the size of the ceramic honeycomb formed body tends to decrease. When the average temperature of the soil is high, the size of the ceramic honeycomb formed body after drying tends to increase. Therefore, when the size of the ceramic honeycomb formed body changes with the lapse of the manufacturing operation time, the size of the ceramic honeycomb formed body and the ceramic honeycomb structure may change. Therefore, it is preferable that the temperature of the cylindrical clay is as constant as possible during the production operation.

  The container for holding the cylindrical clay is not particularly limited as long as the internal temperature can be kept constant. For example, a heater or cooler is attached to a box-shaped container with an openable / closable heat insulating material, and the inside of the container or the temperature-controlled room or temperature-controlled room is maintained at a set temperature by the heater or cooler. What is being done is mentioned.

  The temperature in the container holding the cylindrical clay or the temperature-controlled room is preferably 5 to 20 ° C, more preferably 10 to 15 ° C. In this case, the temperature in the container or the temperature-controlled room may be higher or lower than the average temperature of the cylindrical clay put in the container or the temperature-controlled room. In addition, the time for holding the cylindrical clay can be appropriately selected depending on the size of the cylindrical clay and the partial temperature difference before the cylindrical clay is put in the container or the temperature-controlled room. Preferably it is 15 hours.

(3) Extrusion molding:
The cylindrical clay taken out from the container at a constant temperature or from the temperature-controlled room is loaded into a plunger type extruder, and a ceramic honeycomb formed body is extruded by the plunger type extruder. At this time, the partial temperature difference of the cylindrical clay charged in the plunger type extruder is set to 5 ° C. or less. This temperature difference is particularly preferably 2 ° C. or less, and most preferably 0 ° C.

  The average temperature of the cylindrical clay charged in the plunger type extruder is preferably 5 to 20 ° C, more preferably 10 to 15 ° C. If the average temperature when the cylindrical clay is charged into the plunger-type extruder is lower than 5 ° C, the cylindrical clay may be soft and may partially deform during molding. In addition, since the cylindrical clay is hard and the fluidity at the time of extrusion becomes poor, the outer peripheral wall surface of the ceramic honeycomb molded body becomes rough, and a sacrificial defect may occur.

  As shown in FIG. 2, the plunger-type extruder 11 includes a cylindrical plunger tube 12, a base and a base fixing jig 13 attached to one end of the plunger tube 12, and a plunger tube. It is preferable to include a plunger 14 that is inserted into and removed from an opening portion on the other end side of 12. And when performing extrusion molding, the cylindrical clay 4 is inserted into the plunger tube 12, pressure is applied to the cylindrical clay 4 with the plunger 14 from the other end side of the plunger tube 12, and the base To form a ceramic honeycomb formed body 16. Here, FIG. 2 is a schematic diagram showing a process of forming a ceramic honeycomb formed body with a plunger type extruder.

  When the ceramic honeycomb formed body 16 is formed by the plunger-type extruder 11, the temperature of the inner surface of the plunger tube 12 is 5 ° C. or more and ± 5 ° C. with respect to the average temperature of the cylindrical clay 4. It is preferable that it is the range of these. If the temperature is lower than 5 ° C. or lower than “the average temperature of the cylindrical clay −5 ° C.”, the ceramic honeycomb formed body may be deformed at the time of forming. Further, even when the temperature is higher than “average temperature of cylindrical clay + 5 ° C.”, the ceramic honeycomb formed body may be deformed during forming.

  Since it is preferable that the plunger tube 12 of the plunger-type extruder 11 can control the temperature of the inner surface thereof as described above, for example, as shown in FIG. 2, a jacket 15 is formed. Is preferred. The temperature is preferably controlled by flowing a coolant or a heat medium through the jacket 15. Further, for temperature control, a pipe may be wound in a coil shape, and a refrigerant or the like may be flown therethrough, or an electric heater or the like may be used for heating.

  Although there is no restriction | limiting in particular as a plunger type extrusion molding machine, The thing which can control the temperature of the inner surface of a plunger tube as mentioned above is preferable.

  There is no restriction | limiting in particular as a shape of the ceramic honeycomb molded object to produce, For example, what formed the several cell penetrated between two end surfaces by the honeycomb-shaped partition can be mentioned. The overall shape of the ceramic honeycomb formed body is not particularly limited, and examples thereof include a cylindrical shape, a quadrangular prism shape, and a triangular prism shape. Moreover, there is no restriction | limiting in particular also about the cell shape (cell shape in a cross section perpendicular | vertical with respect to the cell formation direction) of a honeycomb molded object, For example, a square, a hexagon, a triangle etc. can be mentioned. In order to produce a ceramic honeycomb formed body having such a shape, the die may be adapted to the shape of the target ceramic honeycomb formed body. It is preferable to use a die having a desired cell shape, partition wall thickness, and cell density.

(4) Firing:
A ceramic honeycomb structure is obtained by firing the extruded ceramic honeycomb formed body. The ceramic honeycomb formed body is preferably dried before firing. The drying method is not particularly limited, and conventionally known drying methods such as hot air drying, microwave drying, dielectric drying, reduced pressure drying, vacuum drying, freeze drying and the like can be used. Especially, the drying method which combined hot air drying, microwave drying, or dielectric drying is preferable at the point which can dry the whole molded object rapidly and uniformly.

  In the method for manufacturing a ceramic honeycomb structure of the present invention, the ceramic honeycomb formed body may be calcined before firing (main firing). “Preliminary firing” means an operation of burning and removing organic substances (organic binder, pore former, surfactant, etc.) in the honeycomb formed body, and is also referred to as degreasing, debinding, or the like. Generally, the combustion temperature of the organic binder is about 100 to 300 ° C., the combustion temperature of the pore former is about 200 to 800 ° C., and the combustion temperature of the surfactant is about 100 to 400 ° C. Therefore, the calcining temperature is 100 to 800 ° C. What is necessary is just about ℃. There is no restriction | limiting in particular as calcination time, Usually, it is about 2 to 10 hours.

  Finally, a ceramic honeycomb structure is obtained by firing (main firing) the calcined body obtained as described above. “Main firing” means an operation for sintering and densifying the forming raw material in the calcined body to ensure a predetermined strength. As the firing conditions (temperature / time), the ceramic molded body is preferably fired at 1200 to 2300 ° C., and the firing time is preferably 1 to 5 hours. Examples of the firing atmosphere include an air atmosphere, an atmosphere in which oxygen and nitrogen are mixed at an arbitrary ratio, and the like.

The ceramic honeycomb structure obtained by the method for manufacturing a ceramic honeycomb structure of the present invention is preferably a columnar structure having an axial length of 500 to 2000 mm and a cross-sectional area of 700 to 70000 mm ² perpendicular to the axial direction. When a ceramic honeycomb structure having a size in such a range is manufactured, partial deformation is likely to occur. Therefore, this range is the range where the effect of the method for manufacturing a ceramic honeycomb structure of the present invention is most exhibited. is there.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

Example 1
As the ceramic aggregate particle material, alumina distributed to have a particle size of 5 to 300 μm is used, and as this, a glass frit having a particle size of 0.5 to 5 μm as an inorganic sintering aid, methyl cellulose as an organic binder, and as a dispersant Polyethylene glycol was prepared. Subsequently, aggregate particles: inorganic sintering aid: water: organic binder: dispersant were mixed at a mass ratio of 100: 11: 13: 3.5: 0.9 using a kneader to obtain a kneaded product at 16 ° C. . The obtained kneaded material was charged into a vacuum kneader to obtain a cylindrical clay. The average temperature of the cylindrical clay was 10 ° C, the highest temperature was 14.8 ° C, and the lowest temperature was 6.9 ° C. The obtained cylindrical clay is placed in a container or a constant temperature room where the internal temperature is controlled at 4 ° C., and held for 4 hours, so that the average temperature of the cylindrical clay is 4 ° C. and the maximum temperature of the cylindrical clay is 4.2. The minimum temperature of the cylindrical clay was 3.8 ° C. Here, the partial temperature difference of the temperature-controlled cylindrical clay (temperature difference between inside and outside of the cylindrical clay) was 0.4 ° C. The temperature-controlled cylindrical clay taken out from the container was charged into a plunger-type extruder, and a ceramic honeycomb formed body was extruded. In the plunger type extrusion molding machine, a die having a cell partition wall of 650 μm and a total cell number of 2000 cells was used as the cell structure of the obtained ceramic honeycomb molded body. The cross-sectional shape perpendicular to the axial direction of the cell was a square. The inner surface temperature (plunger tube temperature) of the plunger tube was controlled at 4 ° C. The obtained ceramic honeycomb molded body was dried at 100 ° C. for 40 hours using a hot air dryer. Then, the finally dried ceramic honeycomb formed body was fired at 1400 ° C. for 3 hours using a firing furnace to obtain a cylindrical ceramic honeycomb structure of 200 mmφ × 1500 mmL.

  In the above method for manufacturing a ceramic honeycomb structure, the state of occurrence of the crust on the outer peripheral surface when the ceramic honeycomb formed body was extrusion-molded (the generation of crust) was visually observed. Further, the cell deformation state (cell deformation occurrence) after the ceramic honeycomb formed body was dried was measured. Each measurement item is defined as follows. The obtained results are shown in Table 1.

Cylindrical clay temperature:
The cylinder-shaped clay temperature is divided into 8 parts radially from the center at the center part in the length direction and the part that enters the center part by the radius of the cross section from both ends in the length direction, and further in the radial direction. The temperature at each one of the three portions and the temperature at each of the outer peripheral portions divided into eight portions (a total of 25 locations) were measured (indicated by “◯” in FIG. 3). Therefore, a total of 25 × 3 = 75 temperatures were measured.

Cylindrical clay average temperature:
It is an average value of 75 locations of the cylindrical clay temperature.

Cylindrical clay temperature difference:
This is the value obtained by subtracting the minimum temperature of the cylindrical clay from the maximum temperature of the cylindrical clay.

Plunger tube temperature:
This is a value obtained by measuring the temperature of each part when the plunger tube is divided into three equal parts in the longitudinal direction and taking the average of three points in total.

Occurrence:
Check the state of the crumbs visually.

Cell deformation:
When the value obtained by dividing the “diameter of the partial cell inscribed circle (minimum value)” of the ceramic honeycomb formed body by the “diameter of the cell inscribed circle at the center” is 0.8 or less, cell deformation is caused. It was determined that it occurred. “Partial cell inscribed circle diameter (minimum value)” refers to the diameter of the inscribed circle for a cell forming the smallest inscribed circle among all the partial cells.

(Examples 2 to 24, Comparative Examples 1 and 2)
Average temperature of cylindrical clay, maximum temperature of cylindrical clay, minimum temperature of cylindrical clay, temperature difference of cylindrical clay, plunger tube temperature, and average temperature of cylindrical clay (a) and plunger tube temperature (b The ceramic honeycomb structure was manufactured in the same manner as in Example 1 (Examples 2 to 24, Comparative Examples 1 and 2) except that the temperature difference (ab) was changed as shown in Table 1. Was made. Each measurement was performed in the same manner as in Example 1. The results are shown in Table 1.

  From Table 1, according to the manufacturing method of the ceramic honeycomb structure of Examples 1-24, since a cylindrical clay temperature difference is 5 degrees C or less, cell deformation is also suppressed and a favorable ceramic honeycomb structure can be obtained. did it. On the other hand, according to the manufacturing methods of Comparative Examples 1 and 2, since the temperature difference of the cylindrical clay exceeded 5 ° C., a ceramic honeycomb structure with large cell deformation was obtained.

  The present invention collects dust and other particulate matter contained in incineration exhaust gas generated during incineration of automobile exhaust gas and waste, and further, NOx, CO and HC, etc. in the exhaust gas, Removes impurities such as suspended matter, bacteria, and dust mixed in fluids (liquids and gases) in a wide range of fields such as water treatment and medicine / food, for adsorption / absorption by the supported catalyst. Therefore, it can be used for producing a ceramic honeycomb structure suitably used for this purpose.

It is a schematic diagram which shows the process of producing the cylindrical clay in one Embodiment of the manufacturing method of the ceramic honeycomb structure of this invention. It is a schematic diagram which shows the process of forming a ceramic honeycomb molded object with the plunger type extrusion molding machine in one Embodiment of the manufacturing method of the ceramic honeycomb structure of this invention. It is sectional drawing which showed the temperature measurement part in the cross section cut | disconnected in the center part of the length direction of the cylindrical clay in one Embodiment of the manufacturing method of the ceramic honeycomb structure of this invention. It is sectional drawing which shows the temperature measurement part of the cylindrical clay in other embodiment of the manufacturing method of the ceramic honeycomb structure of this invention.

Explanation of symbols

1: Kneading machine, 2: Kneaded material, 3: Vacuum clay kneading machine, 4: Cylindrical clay, 5: Temperature measurement location, 11: Plunger type extruder, 12: Plunger tube, 13: Die and die Fixing jig, 14: plunger, 15: cooling jacket, 16: ceramic honeycomb formed body.

Claims (6)

A kneaded material containing a ceramic raw material, an organic binder and water is charged into a vacuum kneader, a cylindrical clay is formed by the vacuum kneader, and the cylindrical clay is turned into a plunger type extruder. A method for producing a ceramic honeycomb structure, comprising extruding a ceramic honeycomb molded body with the plunger-type extruder and firing the ceramic honeycomb molded body to form a ceramic honeycomb structure,
A method for manufacturing a ceramic honeycomb structure, wherein a partial temperature difference of the cylindrical clay charged in the plunger type extruder is 5 ° C or less.   The method for manufacturing a ceramic honeycomb structure according to claim 1, wherein an average temperature of the cylindrical clay charged in the plunger-type extruder is 5 to 20 ° C.   After the cylindrical clay is formed by the vacuum kneader, the obtained cylindrical clay is held in a constant temperature container or constant temperature chamber, and the temperature difference between the cylindrical clays is 5 ° C. or less. The manufacturing method of the ceramic honeycomb structure according to claim 1 or 2, wherein the cylindrical clay is charged into a plunger type extruder.   4. The temperature of the inner surface of the plunger tube of the plunger type extruder is 5 ° C. or more and is in a range of ± 5 ° C. with respect to the average temperature of the cylindrical clay. 5. Method for manufacturing a ceramic honeycomb structure.   The method for producing a ceramic honeycomb structure according to any one of claims 1 to 4, wherein the plunger-type extruder can control the temperature of the inner surface of the plunger tube. The ceramic honeycomb structure according to any one of claims 1 to 5, wherein the obtained ceramic honeycomb structure is a columnar structure having an axial length of 500 to 2000 mm and a cross-sectional area of 700 to 70000 mm ² perpendicular to the axial direction. Production method.

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