JP5150231B2 - Manufacturing method of honeycomb segment bonded body - Google Patents

Description

  The present invention relates to a method for manufacturing a joined honeycomb segment using dummy segments.

  Dust collection filter for exhaust gas, for example, diesel particulate filter (DPF) for capturing and removing particulate matter (particulate) such as soot contained in exhaust gas from diesel engines, etc. for environmental improvement and pollution prevention As such, honeycomb structures are widely used. At present, for example, SiC DPF is manufactured by joining and integrating with divided base materials (honeycomb segments) in order to prevent cracking due to thermal shock (for example, Patent Document 1).

  By the way, in the conventional technology, when manufacturing such a diesel particulate filter (DPF), in the outer periphery processing of the DPF, the four corner segments are completely cut, and the cut and unused segments are always generated. This was a problem in terms of environment and production costs.

  In particular, in order to cut the unused honeycomb segment, it is common that the cutting process is performed by a grinding means such as a diamond tool, but such an industrial diamond is expensive, if the cutting area is large, As a result, the wear of industrial diamonds has progressed, and as a result, the manufacturing cost has been raised, raising the overall cost. In addition, the human and time resources spent on production and cutting processes of segments that are not completely used are not only small, but also a heavy burden.

  Furthermore, from the environmental and cost considerations, the scraped segments are crushed and reused as segments, but the production process as a streamline is complicated and diverse. At the same time, the cost is increased.

  In order to deal with such problems, it has been proposed to produce the product without (extracted) the corner segments. However, if the corner segments are removed and the segments are joined, the corners are removed during the drying process. It becomes easy to be exposed to the outside air as much as there are no segments, for example, drying of the segments in the outer circumferential row (or drying of the bonding material that joins the segments) does not proceed evenly or the degree of drying becomes faster, There is a new problem that the joining width of the outer circumferential row of the segment bodies (segment joined bodies) becomes thin.

  Furthermore, in addition to the new problem described above, when joining honeycomb segments with the corner segments eliminated, the applied pressure is not evenly transmitted to the segment body during the pressurizing process with a pressurizing cylinder or the like. Further, there is a problem that the balance of the applied pressure is deteriorated and the joining width of the outer peripheral row of the segment body is reduced.

  As described above, as a method of joining the segments that are not different from the state where the corner segments are present without the corner segments, the fundamental solution has not yet been reached, and it has not been sufficient yet. .

JP 2003-10616 A

  The present invention has been made to solve the above problems, and when joining the honeycomb segments, each segment, especially the segment located on the outer periphery, can be dried in a balanced manner, and the segment body (joined body) can be evenly distributed. Provided is a method for manufacturing a joined honeycomb segment using a dummy segment, which can maintain a stable joining width and achieve cost reduction by being able to perform pressurization.

  The present invention provides a bonding method using the following dummy segments.

[1] A method for manufacturing a honeycomb structure made of ceramics, including a joining step in which a plurality of honeycomb segments having a plurality of cells that are partitioned by partition walls and penetrate in the axial direction are joined together by a joining material. A honeycomb segment joined body manufacturing method using a recyclable dummy segment instead of a honeycomb segment at any corner, and the joining step obtains a joined body obtained by joining the honeycomb segment and the dummy segment. A bonded honeycomb segment assembly having a drying step of drying the obtained bonded body after the bonding step, and further removing the dummy segments after the drying step to produce a bonded honeycomb segment assembly And the dummy segment has a compressive elastic modulus of 2.0 to 10 GPa And the dummy segment has a heat-resistant temperature of 120 ° C. or higher .
[2] Production of the bonded honeycomb segment according to [1], wherein the bonded body obtained in the bonding step is further subjected to a pressing step for adjusting a bonding width by pressurizing, and then the drying step is performed. Method.

[ 3 ] The method for manufacturing a joined honeycomb segment according to [1] or [2] , wherein the dummy segment is used at least in a corner portion in contact with the ground plane.

[ 4 ] The method for manufacturing a joined honeycomb segment according to any one of [1] to [3], wherein the dummy segment is used at all corners.

  According to the present invention, each honeycomb segment, in particular, the honeycomb segment on the outer periphery can be dried in a balanced manner, and the honeycomb segment body (honeycomb segment bonded body) can be uniformly pressurized, thereby maintaining a stable bonding width. In addition, it is possible to provide a method for producing a bonded honeycomb segment assembly using dummy segments that can achieve cost reduction.

  Hereinafter, the best mode for carrying out the joining method using the dummy segment of the present invention will be specifically described. However, the present invention broadly encompasses a joining method using dummy segments having the invention-specific matters, and is not limited to the following embodiments.

[1] Configuration of a method for producing a joined honeycomb segment assembly of the present invention:
As shown in FIGS. 7 and 8, one embodiment of a method for manufacturing a joined honeycomb segment assembly according to the present invention is to join a plurality of honeycomb segments 3 having a plurality of cells partitioned by partition walls and penetrating in the axial direction. A method for manufacturing a honeycomb structure made of ceramics including a joining step that is integrated by joining with a material 4, wherein a reusable dummy segment is used instead of a honeycomb segment segment in any corner 6. Is.

[1-1] Manufacturing process of honeycomb segment bonded body:
As shown in FIG. 1, the manufacturing process of the joined honeycomb segment assembly is performed through steps S1 to S7. First, a base material (honeycomb segment) is produced (S1). Next, a bonding material is produced (S2). Further, a dummy segment is produced (S3). Then, as the dummy segment is arranged in place of the honeycomb segmenting preparative the corners of either integrally bonded to the honeycomb segments using the bonding material to obtain a conjugate (S4). The joined body obtained in S4 is pressurized with a predetermined pressure from the outer peripheral surface of the joined body with a pressurizer or the like, and adjusted to a uniform joining width (S5). The joined body obtained after the step S5 is dried with hot air or the like (S6). The dummy segment is removed from the dried joined body to obtain a honeycomb segment joined body (S7). Thereafter, a desired shape is cut with a diamond tool or the like as necessary (S8). In addition to these manufacturing processes, if there is protrusion of the bonding material, a masking tape may be applied to the outer peripheral surface of the honeycomb segment to prevent adhesion of the bonding material or to scrape the bonding material. preferable. Moreover, it is more preferable to leave it at room temperature for a certain time before drying with hot air and then dry with hot air.

  In addition to the above steps S1 to S8, when the joined honeycomb segment assembly 1 of the present invention is used as a filter, as shown in FIGS. 7 and 8, some of the cells 12 are plugged at the end faces of the honeycomb segments. It is preferable that In particular, it is preferable that the adjacent cells 12 are alternately sealed at the opposite end surfaces, and the end surfaces are sealed in a checkered pattern. By sealing in this way, for example, the fluid to be treated which flows from one end face flows out from the other end face through the partition wall, and the porous partition wall serves as a filter when the fluid to be treated passes through the partition wall. The target product can be removed.

[1-2] Honeycomb segment:
As shown in FIGS. 7 and 8, the honeycomb segment 3 has a plurality of cells partitioned by the partition walls 11 and penetrating in the axial direction. In other words, it has a structure in which a plurality of cells 12 that serve as partitions and formed fluid flow paths are arranged in parallel to each other in the central axis direction, each of which constitutes a part of the overall structure, The honeycomb segment 3 constituting the entire structure by being assembled in a direction perpendicular to the central axis of the honeycomb structure H is integrally formed by the layer of the bonding material 4S formed from the bonding material composition of the present invention. It is configured as a bonded honeycomb segment assembly.

  After the joining, the joined honeycomb segment assembly 1 integrally joined by the joining material layer 4S is ground so that the overall cross-sectional shape thereof becomes a circle, an ellipse, a triangle, a square, and other desired shapes. The surface is covered with the coating material 13. When this honeycomb structure H is used as a DPF, as shown in FIG. 8 and FIG. 9 which is an AA cross-sectional view thereof, each cell 12 of the honeycomb segment 3 is provided at one end, respectively. It is good to seal with the filler 14 alternately.

  As the material of the honeycomb segment, from the viewpoint of strength and heat resistance, a silicon-silicon carbide composite material formed using silicon carbide (SiC) as an aggregate and silicon (Si) as a binder, silicon nitride, cordierite Suitable examples include at least one material selected from the group consisting of mullite, alumina, spinel, silicon carbide cordierite composite, lithium aluminum silicate, aluminum titanate, and Fe-Cr-Al metal. it can. Among these, those made of silicon carbide (SiC) or a silicon-silicon carbide based composite material are preferable. Further, the constituent material of the plugged portion is preferably the same material as that of the honeycomb segment in order to reduce the difference in thermal expansion from the honeycomb segment.

  A conventionally well-known method can be used for the manufacturing method of a honeycomb segment. As an example of a specific method, a binder such as methyl cellulose, hydroxypropoxyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, and polyvinyl alcohol, a pore-forming agent, a surfactant, water as a solvent, and the like are added to the above materials. Then, a plastic clay is formed, and this clay is extruded so as to have a predetermined honeycomb shape, and then dried by microwaves, hot air or the like, and then fired. In addition, after forming a plugging part in a cell, you may make it carry out with baking of a plugging part.

  2A to 2C show a specific example of the joined body 1, schematically showing a joined body produced by joining the honeycomb segments 3 through a joining material, It is the schematic diagram which showed the cross section of the width direction. For example, as shown in FIG. 2A, when the configuration of the joined body 1A is 6 vertical × 6 horizontal, all 36 honeycomb segments 3 are conventionally required. If the dummy segments 5 are arranged at the corners 6 (6a, 6b, 6c, 6d), it is not necessary to use all 36 honeycomb segments 3. Further, for example, when the structure of the joined body is 7 × 7 as shown in FIG. 2B, all 49 honeycomb segments 3 are conventionally required, but any one of the corner portions 6 ( If the dummy segments 5 are arranged at 6e, 6f, 6g, 6h), it is not necessary to use all 47 honeycomb segments 3. Further, for example, as shown in FIG. 2C, when the structure of the joined body is 8 × 8, a dummy segment 5 (described later) is placed in any one of the corners 6 (6i, 6j, 6k, 6l). If all the honeycomb segments are arranged, it is not necessary to use all 62 honeycomb segments. Therefore, the effect of the present application can be achieved.

  Here, the “bonded body” refers to a structure in which a dummy segment and a honeycomb segment are bonded via a bonding material, and is obtained through the steps up to S4 in FIG. 1 described above. The “honeycomb segment bonded body” refers to a structure obtained by removing the dummy segment from the above-described bonded body, and in FIG. 1 described above, is obtained through the process of S7.

  The above-mentioned “at least one corner” is not limited to the case of (1) any one of the corners of 6a to 6d, and (2) 6a and 6b, taking FIG. 2A as an example. When referring to any two corners such as 6a and 6c, 6a and 6d, 6b and 6c, 6b and 6d, 6c and 6d, (3) 6a and 6b and 6c, 6a and 6b and 6d, 6a and 6c, When referring to any three corners such as 6d, 6b, 6c, and 6d, it further includes the case of (4) four corners such as 6a, 6b, 6c, and 6d.

  More preferable is a joined body obtained by disposing dummy segments in at least two corners in contact with the ground plane. For example, as shown in FIG. 2A, in the case where the structure of the joined body 1A is 6 vertical × 6 horizontal, at least two corner portions 6 (6a, 6b) that are in contact with the ground surface are provided with dummy segments 5 (5a 5b) is preferable because 34 honeycomb segments 3 are sufficient. Further, for example, as shown in FIG. 2B, when the structure of the joined body is 7 × 7, dummy segments 5 (5c, 5d) are provided at least at the two corners 6 (6e, 6f) in contact with the ground plane. ) Is preferable because 47 honeycomb segments 3 are sufficient. Further, for example, as shown in FIG. 2C, when the configuration of the joined body is 8 × 8, dummy segments 5 (5 e, 5 f) are at least at the two corners 6 (6 i, 6 j) in contact with the ground plane. ) Is preferable because 62 honeycomb segments are sufficient.

  As shown in FIGS. 3A to 3C, when the dummy segment 5 is used for all four corners, the present invention is not limited to this, and the case of a joined body 1D having a configuration of 6 vertical x 6 horizontal. In this case, four dummy segments 5 (5g, 5h, 5i, 5j) are used, and 32 honeycomb segments 3 may be used. In the case of the joined body 1F having a structure of 7 × 7, dummy By using four segments 5 (5k, 5l, 5m, 5n), it is sufficient that the number of honeycomb segments 3 is 45. In the case of the joined body 1G having the configuration of 8 × 8, the dummy segments 5 are 4 By using this (5p, 5q, 5r, 5s), it is sufficient that the number of honeycomb segments 3 is 60, which is more preferable.

  Further, the number of components of the joined body is not limited to the above-described example, and the number of components in the vertical or horizontal direction is increased or decreased as necessary, for example, the configuration of vertical 3 × horizontal 3 = 9 And a joined body composed of 9 verticals × 9 horizontals = 81. This is because the effect of the present invention can be achieved by using dummy segments instead of honeycomb segments at corners where the joined honeycomb segment assembly is not used.

[1-3] Dummy segment:
The dummy segment 3 is used in place of the honeycomb segment, and as shown in FIGS. 2A to 2C and FIGS. 3A to 3C, the dummy segment 3 is disposed at any corner of the joined body 1. To be joined. The dummy segment is arranged at the corner of the joined body in the cutting process when the segment body is processed, and the segment located at the corner is completely cut and becomes unnecessary, but the honeycomb segment is formed at the corner. If not arranged or dummy segments are not arranged, the bonding material is not properly dried, and the drying of the segments arranged on the outer periphery proceeds more than the segments arranged inside, and as a result, This is to prevent such adverse effects because the mechanical strength and the like are also impaired.

  In addition, after applying the bonding material, etc., a pressurizing process for adjusting the bonding width is generally performed in the manufacturing process, but in the pressurizing process, there is no corner honeycomb segment. The applied pressure is easily transmitted, the joining width of the outer circumferential row becomes thin, and the mechanical strength is also inferior. Here, FIGS. 4A and 4B schematically show the displacement at the time of bonding pressurization that occurs when the bonded body is formed without arranging the honeycomb segment and the dummy segment at the corner. is there. As shown in FIG. 4A, neither the honeycomb segment nor the dummy segment is arranged at the corner 6 (6m, 6n, 6p, 6q) of the joined body to which the joining material is applied. Therefore, such a bonded honeycomb segment assembly is respectively applied toward the pressurization reference surface 9a from the top to the bottom of FIG. 4B or from the right to the pressurization reference surface 9b. When pressure is applied by the pressure cylinders 9a and 9b, the pressure is easily transmitted to the segments 3 constituting the honeycomb segment bonded body by the amount where the honeycomb segments are not arranged, and the bonding is applied to the honeycomb segments located on the outer periphery. The joint width of the material becomes thin, and properties such as mechanical strength may be impaired. Needless to say, the pressurizing direction is the same even if the direction of pressure is changed upside down and left and right.

Furthermore, since the pressurization is easily transmitted, there may be a problem that the joining surface is displaced. In particular, since the rows (honeycomb segment group) of the X ₁ and X ₂ honeycomb segments shown in FIG. 4A do not have the honeycomb segments at the corners 6p and 6q, the segments 3c and 3d have a corresponding load such as gravity. For this reason, a joining location (joining surface 4c, 4d) tends to shift | deviate only by own weight. Therefore, in order to prevent such a shift of the joint location, it is more preferable that the dummy segment is used at least in a corner portion in contact with the ground plane. In this way, when arranged at least on the ground contact surface, the weight of the stacked honeycomb segments can be supported by the dummy segments, and further, the honeycomb segments that should have been originally arranged at the corners need not be used. Therefore, the effect of the present application can be further exhibited. Therefore, it is one of the preferred forms.

  Here, “at least the corners arranged on the ground plane” means two corners in contact with the ground plane among the four corners of the joined body. For example, in FIG. It refers to corners where dummy segments are arranged at two locations 6p and 6q.

  It should be noted that both the so-called horizontal placement in which the length direction of the honeycomb segment is in contact with the installation surface, and the so-called vertical placement in which the cross section in the width direction of the honeycomb segment is in contact with the installation surface. Preferably, at least one dummy segment is disposed at each of the two end portions in contact with the ground plane. If at least the dummy segment is not disposed at the end (corner) on the ground surface side, the weight of the honeycomb segment disposed on the end (corner) cannot be supported as described above, and the joining surface may be displaced. This is because there is a possibility that the characteristics required for the joined honeycomb segment assembly, such as mechanical strength, may be impaired. In addition, the degree of drying may be biased, and the bonding width may not be within a desired range. In other words, if at least one dummy segment is disposed at each of the two end portions in contact with the ground plane, the above-mentioned weight can be supported, and an appropriate joining width in the drying process can be obtained. Since the waste of arranging honeycomb segments that are not used for cutting or the like can be eliminated, the effects of the present application can be achieved.

  Here, “pressurization” using a pressure cylinder means that a predetermined pressure is applied to the honeycomb segment by a pressure cylinder or the like in the joining process, and it is easy to join the joining material to the joining surface of each segment without fail. At the same time, the bonding width of the bonding surface is adjusted, and excess bonding material is removed from the bonding surface. In addition, the “pressurization reference surface” is a contact surface with the joined body that can temporarily fix the joined body so that the pressurized joined body is supported or laterally supported to eliminate the displacement of the joined state. Say.

  In addition, as the “corner portion in contact with the ground plane”, for example, in the case of the joined body 1A composed of 6 vertical × 6 horizontal shown in FIG. 2A, it corresponds to the reference numerals 6a and 6b and is shown in FIG. 2B. In the case of the joined body 1B composed of 7 × 7, it corresponds to the reference numerals 6e and 6f, and corresponds to the reference numerals 6i and 6j in the case of the joined body 1C composed of 8 × longitudinal 8 shown in FIG. 2C.

  The dummy segment is formed so as to be recyclable. That is, after passing through a pressurizing step S5 for adjusting the joining width by pressurizing from a joined body obtained by joining the dummy segment and the honeycomb segment, and a hot air drying step S6 for drying with hot air or the like, only the dummy segment is joined to the joined body (segment body). It is formed so that it can be used again in the joining process of the joined body. In other words, the dummy segments can be separated (removed), and only the obtained bonded honeycomb segment assembly can be advanced to the next cutting step S8 as necessary. Therefore, in the cutting process or the like, the cutting area is reduced by the amount of the dummy segment body arranged at the corner portion 6 of the joined body, and the removed dummy segment can be reused after a washing process of washing with water or the like. . Thus, the time required for the dummy segment cutting process can be saved and the overall cost can be reduced, so that the effects of the present invention can be achieved.

  The dummy segment is removed by pulling the dummy segment away from the joined body by hand. Moreover, you may pull apart with the machine etc. which can clamp the edge part in the length direction of a dummy segment. The dummy segment is formed of a material that is easily peeled off from the joined body. Therefore, the location of the dummy segment is configured to be easily removed from the joined body (easily released from the mold) by being pulled with an appropriate force unlike the other segments. In addition, as shown in FIGS. 5A to 5C, the joined honeycomb segment assembly obtained by removing the dummy segment in this manner has no segment at the corner, but can withstand its own weight through the drying step S7. Since the strength is obtained, the joining portion is not displaced. Thus, the obtained bonded honeycomb segment assembly is then subjected to a process such as cutting as necessary.

In the case where the joined body is configured by arranging two dummy segments at least at the corners in contact with the ground plane, the joined body shown in FIGS. 6A and 6B may be used in addition to the above-described example. , Included in this embodiment. FIG. 6A is a schematic diagram illustrating a case where neither the honeycomb segment nor the dummy segment is present in the corner portions 6t and 6u corresponding to the upper side of the corner portion in contact with the ground contact surface. Even in such a bonded body, the honeycomb segment group X ₃ , X in which the dummy segments 5t and 5u arranged at the corners 6r and 6s located on the ground contact surface side are laminated on the outer peripheral side via a bonding material. ₄ can be supported, and at least the bonding width can be prevented from being thinned by pressurization during the pressurization step. In addition, the number of honeycomb segments can be reduced by four. One of them. In FIG. 6B, the dummy segments 5v and 5w are arranged only at the corners 6v and 6w in contact with the ground contact surface, and the honeycomb segments 3 are arranged at the corners 6x and 6y corresponding to the upper side of the corners. It is a schematic diagram showing a body. Even in such a bonded body, the honeycomb segment groups X ₅ , X in which the dummy segments 5v, 5w arranged at the corners 6v, 6w located on the grounding surface side are laminated on the outer peripheral side via the bonding material. ₆ can be supported. In addition, the dummy segment can at least prevent the bonding width from being reduced by pressurization during the pressurization step. Furthermore, since the honeycomb segments can be reduced by at least two, the effects of the present invention can be obtained, which is one of the embodiments.

  However, it is more preferable to use dummy segments at all corners. By placing dummy segments in all corners and joining with other honeycomb segments, not only the so-called horizontal placement described above, but also the case of grounding along the cross section of the joined body, that is, so-called vertical placement Even in this case, the bonding width can be kept at a desired thickness at the time of pressurization during bonding, which is substantially the same as the honeycomb segments arranged at the four corners. Further, since the degree of drying of the joined portions of the honeycomb segments arranged on the outer peripheral surface is balanced and a joined honeycomb segment assembly that can satisfy the mechanical strength and the like can be formed, this is one of the more preferable embodiments.

  When dummy segments are arranged in all corners, four dummy segments are arranged in each corner of FIGS. 3A, 3B, and 3C, and therefore, from the 6 vertical × 6 horizontal shown in FIG. 3A. In the case of the joined body, two corners 5i and 5j that are in contact with the ground contact surface and two corners 5g and 5h that are located at the uppermost stage where the honeycomb segments are stacked from each corner are used. Instead, what was supposed to be completely scraped off (cut) is replaced with a dummy segment. Also, for example, in the case of a joined body consisting of 7 vertical x 7 horizontal shown in FIG. 3B, two corner portions 5m and 5 in contact with the ground contact surface, and honeycomb segments were stacked from each corner portion. The two corners 5k and 5l positioned at the uppermost step are replaced with dummy segments, and in the case of the joined body of 8 verticals × 8 horizontals shown in FIG. 3C, the corner 5r in contact with the grounding surface. Two corners 5p and 5q located at the uppermost step where the honeycomb segments are stacked are replaced with dummy segments from the two corners 5s and the corners thereof.

  In addition, the dummy segment used in the present embodiment has a minimum hardness that can withstand drying and transmit pressure, and has a softness that does not damage the segment, and needs to be easily peeled off after drying. Therefore, it is desirable to form with the material which consists of a fluororesin type and a general polymer type.

  The fluororesin system includes polytetrafluoroethylene (tetrafluoroethylene), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene / hexafluoropropylene copolymer (4.6 fluoro), tetrafluoroethylene / Examples thereof include ethylene copolymers, polyvinylidene fluoride (difluoride), polychlorotrifluoroethylene (trifluoride), and chlorotrifluoroethylene / ethylene copolymers.

  Examples of general polymer systems include polyetherimide, polyphenylene sulfide, polyetheretherketone, polyamideimide, polyimide, polybenzimidazole, 6 nylon, 66 nylon, and the like.

The dummy segments that have a compression modulus of 2.0～10GPa. When the compression elastic modulus of the dummy segment is higher than 10 GPa, the pressure of the pressure cylinder or the like is too strong at the time of bonding pressurization, and the honeycomb segment bonded body is damaged. If it is lower, the pressure of the pressurizing cylinder or the like at the time of pressurization is absorbed by the dummy segment because it is too soft, and the pressure is not sufficiently transmitted to the honeycomb segment through the dummy segment, and the joining width is larger than the desired thickness. Is also not preferable because it becomes thicker.

The dummy segments that have a heat resistant temperature of more than 120 ° C.. In the drying process in which the dummy segment and the honeycomb segment are joined through a joining material and dried, hot air of about 120 ° C. is blown and dried with a microwave or a hot air drier. Therefore, when the heat-resistant temperature of the dummy segment is 120 ° C or less, the dummy segment may be melted. When the dummy segment is removed, the dummy segment cannot be removed or may not be removed cleanly. It is because it can also damage. Furthermore, the dummy segment cannot be reused .

  Moreover, it is preferable that the joining width of the joined body joined using the dummy segment is within a range of 1.0 ± 0.5 mm. By adjusting the bonding width within this numerical value, a DPF having mechanical strength / elasticity and the like can be molded.

  Further, by using dummy segments in this way, for example, the number of groups shown in the following table 1 is 6 vertical x 6 horizontal (see FIG. 10), 7 vertical x 7 horizontal (see FIG. 11), If the segment body is composed of 8 vertical x 8 horizontal (see FIG. 12), the segment usage rate can be increased. That is, if the length is 6 × width, the segment usage rate of the finished product (after the cutting process) obtained without using the dummy segment (cross-sectional area of the finished body / cross-sectional area of the joined body × 100) is 57. The finished product (after the cutting step S8) obtained by using the dummy segments at the four corners is 63.9%, which is a significant increase in the usage rate. Similarly, if it is 7 vertical x 7 horizontal, it will increase from 60.5% to 65.6%, if it is 8 vertical x 8 horizontal, it will increase from 72.4% to 76.9%. It can be seen that cost reduction can be achieved by using dummy segments without fail. 10-11, the use of the dummy segment means that the dummy segment is used for the four corner segments Z that are painted black, and the completed product (completed shape) is a circle (○ ).

[1-4] Joining material:
As a bonding material, heat-resistant ceramic fibers, ceramic particles and other inorganic adhesives such as colloidal silica, and organic binders (for example, methylcellulose (MC), carboxymethylcellulose) are used as necessary. (CMC), etc.), a dispersant, water, etc. are added, and the mixture is mixed and kneaded using a kneader such as a mixer to give a paste.

  All the honeycomb segments and dummy segments are placed at predetermined positions, joined through a joining material, and then dried and cured. The honeycomb bonded body obtained by separating the dummy segment from the bonded honeycomb segment / dummy segment bonded body is then processed into a cylindrical desired shape by cutting the outer periphery as necessary. May be. In this case, since the outer peripheral wall is removed by processing and the inner wall portion and the cell are exposed, it is preferable to re-form the outer peripheral wall by covering the exposed surface with a coating material.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto. In the following examples and comparative examples, “parts” and “%” mean parts by mass and mass% unless otherwise specified. Various evaluations and measurements in the examples were performed by the following methods.

  In addition, the continuous use temperature and compression elastic modulus of the dummy segment shown in Table 2 described later are based on the JIS standard (A 9511), and it can be said that the higher the use temperature, the higher the heat resistance, and the higher the compression elastic modulus. It can be said that it becomes hard.

[1] Internal joint width:
The bonding width of the honeycomb segments located inside the honeycomb segment bonded body was measured. The measuring method is as follows. A magnifying glass is applied to the obtained joint portion of the dummy segment, and the central portion of each joined side of all the joined portions is measured. For example, as shown in FIG. 13, in the case where the dummy segment is composed of 6 vertical × 6 horizontal, the central portion of each side is indicated by a point P (●) at all joints, and the point P is shown on both sides. Measure and calculate the average value to determine the internal joint width.
[2] Bonding width of outer periphery:
The bonding width of the honeycomb segment located outside the bonded honeycomb segment assembly was measured. The measuring method is as follows. A loupe is applied to the obtained joint portion of the dummy segment, and a joint portion located on the outer periphery, and a central portion of each joined side is measured. For example, as shown in FIG. 14, in the case where the dummy segment is composed of 6 vertical × 6 horizontal, it is a joint located on the outer periphery, and the central part of each joined side is a point P (● ), The point P2 is measured on both sides, and the average value is calculated to obtain the outer joint width.
[3] Release property after drying:
Whether the dummy segment was resistant to drying or not was dried with a hot air dryer at 120 ° C., and the peeling state of the dummy was investigated and observed. This method of investigating releasability can also be performed by a machine, etc., but since it is considered that the work of pulling the dummy segment away from the honeycomb segment (peeling off) is likely to be performed by human power, It was investigated whether it was easily peeled off by hand. Further, the outer peripheral surface of the honeycomb segment after the dummy segment was separated (peeled) from the honeycomb segment was observed using a loupe.

(Manufacture of honeycomb segments)
As a honeycomb segment raw material, SiC powder and metal Si powder are mixed at a mass ratio of 80:20, starch and foamed resin are added as a pore-forming agent, and methylcellulose and hydroxypropoxylmethylcellulose, a surfactant and water are added. Thus, a plastic clay was produced. This kneaded clay is extruded and dried with microwaves and hot air to form a square having a partition wall thickness of 310 μm, a cell density of about 46.5 cells / cm ² (300 cells / square inch), and a cross section of 35 mm on a side, A honeycomb segment formed body having a length of 152 mm was obtained. In this honeycomb segment molded body, both end faces of the cells were sealed so that the end faces had a checkered pattern. That is, the sealing was performed so that adjacent cells were sealed at opposite ends. As the plugging material, the same material as the honeycomb segment material was used. After sealing both ends of the cell and drying, degreasing at about 400 ° C. in an air atmosphere, and then baking at about 1450 ° C. in an Ar inert atmosphere to bond SiC crystal particles with Si. A honeycomb segment having a quality structure was obtained.

(Preparation of bonding material)
Aluminosilicate fibers were used as inorganic fibers, and the shot ratios were all 50%. Water is added to 22% by mass of colloidal silica and 1% by mass of clay as an inorganic binder, and SiC is mixed as inorganic particles. In some cases, an organic binder (CMC, PVA), a foamed resin and a dispersant are added. Then, the mixture was kneaded for 30 minutes to obtain a paste-like bonding material.

(Dummy segment production)
Dummy segments were manufactured from PVDF (polyvinylidene fluoride), PEEK (polyetheretherketone), PA6 (6 nylon), aluminum, and high-density polyethylene. The size of each dummy segment was a regular square with a cross section of 35 mm on a side and a length of 152 mm so as to correspond to the size of the honeycomb segment formed as described above.

(Preparation of honeycomb structure)
A bonding material is coated on the outer wall surface of the honeycomb segment so as to have a thickness of 1 ± 0.5 mm to form a bonding material layer, dummy segments are arranged at four corners, and another honeycomb segment is formed thereon. The mounting process was repeated to produce a honeycomb segment laminate composed of 16 honeycomb segments, pressure was applied from the outside, the whole was joined, and then dried at 140 ° C. for 2 hours to obtain a joined honeycomb segment. .

Example 1
A dummy segment is formed from PVDF (polyvinylidene fluoride), the dummy segment and the honeycomb segment are joined so that the dummy segments are positioned at four corners, and a bonded body 1 is obtained through a pressing process and a drying process. It was.

(Example 2)
A dummy segment is formed from PEEK (polyetheretherketone), and the dummy segment and the honeycomb segment are joined so that the dummy segments are positioned at the four corners. Obtained.

(Example 3)
A dummy segment was formed from PA6 (6 nylon), and the dummy segment and the honeycomb segment were joined so that the dummy segment was positioned at the four corners, and a bonded body 3 was obtained through a pressurizing step and a drying step. .

Example 4
A dummy segment is formed from PVDF (polyvinylidene fluoride), the dummy segment and the honeycomb segment are joined so that the dummy segment is positioned at the upper two corners, and after passing through the pressing step and the drying step, the joined body 4 is formed. Obtained.

(Example 5)
A dummy segment is formed from PEEK (polyetheretherketone), the dummy segment and the honeycomb segment are joined so that the dummy segment is positioned at the upper two corners, and after passing through the pressing step and the drying step, the joined body 5 Got.

(Example 6)
A dummy segment is formed from PA6 (6 nylon), and the dummy segment and the honeycomb segment are bonded so that the dummy segment is positioned at the upper two corners, and a bonded body 6 is obtained through a pressing process and a drying process. It was.

(Example 7)
A dummy segment is formed from PVDF (polyvinylidene fluoride), the dummy segment and the honeycomb segment are joined so that the dummy segment is positioned at the two lower corners, and after passing through the pressing step and the drying step, the joined body 7 Got.

(Example 8)
A dummy segment is formed from PEEK (polyetheretherketone), and the dummy segment and the honeycomb segment are joined so that the dummy segment is positioned at the two lower corners, and then subjected to a pressurizing step and a drying step. 8 was obtained.

Example 9
A dummy segment is formed from PA6 (6 nylon), and the dummy segment and the honeycomb segment are bonded so that the dummy segment is positioned at the upper two corners, and a bonded body 9 is obtained through a pressing process and a drying process. It was.

(Comparative Example 1)
A dummy segment was formed from aluminum, the dummy segment and the honeycomb segment were joined so that the dummy segments were positioned at four corners, and a bonded body 10 was obtained through a pressurizing step and a drying step.

(Comparative Example 2)
Dummy segments were formed from high-density polyethylene, the dummy segments and the honeycomb segments were joined so that the dummy segments were positioned at the four corners, and a bonded body 11 was obtained through a pressurizing step and a drying step.

(Comparative Example 3)
A dummy segment was formed from aluminum, the dummy segment and the honeycomb segment were joined such that the dummy segment was positioned at the upper two corners, and a bonded body 12 was obtained through a pressurizing step and a drying step.

(Comparative Example 4)
A dummy segment was formed from high-density polyethylene, and the dummy segment and the honeycomb segment were joined so that the dummy segment was positioned in the upper two corners, and a joined body 13 was obtained through a pressing process and a drying process.

(Comparative Example 5)
A dummy segment was formed from aluminum, and the dummy segment and the honeycomb segment were joined such that the dummy segment was positioned at the two lower corners, and a bonded body 14 was obtained through a pressing process and a drying process.

(Comparative Example 6)
A dummy segment is formed from high-density polyethylene, and the dummy segment and the honeycomb segment are joined so that the dummy segment is positioned at the lower two corners, and a bonded body 15 is obtained through a pressing process and a drying process. .

(Comparative Example 7)
Without using the dummy segments, the honeycomb segments are pulled out from the upper two corners, and the other honeycomb segments are bonded to each other via a bonding material. Got.

(Comparative Example 8)
Without using the dummy segments, the honeycomb segments are pulled out from the four corners, and the other honeycomb segments are bonded to each other through the bonding material, and after passing through the pressing step and the drying step, the convex bonded body 17 is formed. Obtained.

(Discussion)
As described above, a joined body formed by inserting dummy segments in all four corners, a joined body formed by inserting dummy segments in the upper two corners, and a joined body formed by inserting dummy segments in the lower two corners After the respective bodies and the joined bodies formed without using the dummy segments and the honeycomb segments were obtained, the joined state was observed.

  As shown in Tables 2 and 3, joined bodies obtained by joining dummy segments to all four corners of Examples 1 to 3, and dummy segments at upper two corners of Examples 4 to 6 The joined bodies obtained by joining, and the joined bodies obtained by joining the dummy segments to the two corners in contact with the ground plane in Examples 7 to 9 both have a desired joining width. A good joined body was obtained.

  On the other hand, as shown in Tables 4 and 5, the joined body obtained by joining the dummy segments to all four corners of the comparative examples 1 and 2, and the dummy segments were joined to the upper two corners of the comparative examples 3 and 4. In the joined body obtained in this way, and in the joined body obtained by joining the dummy segments to the lower two corners in contact with the ground contact surfaces of Comparative Examples 5 and 6, problems occurred. Since the dummy segments made of aluminum in Comparative Examples 1, 3, and 5 were harder than the honeycomb segments, the honeycomb segments were damaged during the pressurizing process. From this result, since the elastic modulus of the honeycomb segment is 10 to 20 GPa, it was proved that a material having a higher elastic modulus is not suitable as a dummy segment. Further, in the dummy segments made of high-density polyethylene of Comparative Examples 2, 4, and 6, the segment was not damaged, but was too soft, so that pressure was not transmitted during pressurization and the joining width was thicker than usual. Therefore, it was demonstrated that an appropriate range for the elastic modulus of the dummy segment is 2.0 to 10 GPa.

  Furthermore, in Comparative Examples 7 and 8 obtained as bonded bodies formed without using dummy segments and honeycomb segments, as shown in Table 5, the internal 4 × 4 bonding width was within a desired range. However, the bonding width on the outer periphery becomes thin, and it cannot be used as a DPF. This is probably because the honeycomb segment (or dummy segment) is not arranged at the corner, and thus drying proceeds faster than the honeycomb segment arranged inside. Although not shown in Table 5, when the comparative examples 7 and 8 are molded, the honeycomb segments (or dummy segments) are not arranged at the corners. Just by joining with the material, it could not withstand the weight of its own weight and fell off. Therefore, in Comparative Examples 7 and 8, it was confirmed that the molding process takes more time than necessary and does not contribute to cost reduction or the like.

  Next, the joined body was dried with a hot air dryer at 120 ° C., and the peeled state of the dummy segment was observed. As a result, it is the dummy segments of Examples 1, 4, and 7 made of polyvinylidene fluoride that are most easily peeled off. From this result, the dummy segment made of a fluororesin material having self-lubricating properties is considered most suitable. It is done. Further, in the dummy segments made of the PEEK (polyetheretherketone) material of Examples 2, 5, and 8, and the dummy segments made of the PA6 (6 nylon) material of Examples 3, 6, and 9, the bonding material is somewhat adhered. However, it could be easily removed. Therefore, any adhesion does not affect the post-process and does not affect the characteristics of the DPF, and can be suitably used as a dummy segment. Since the bonding material adhering to the dummy segment can be easily removed by immersing it in water, there is no problem in use.

  On the other hand, in Comparative Examples 1 to 6, it was difficult for the bonding material to be completely fixed to each dummy segment and peeled off. Therefore, it was proved that the dummy segment of any comparative example is not suitable for use as a substitute for the honeycomb segment at any corner, in particular, at the two corners in contact with the ground plane, or at all four corners. .

  INDUSTRIAL APPLICABILITY The present invention can be suitably used as a method for manufacturing a joined honeycomb segment used for a dust collection filter such as DPF.

It is a flowchart figure which shows the manufacturing process of a honeycomb segment bonded body. It is the figure which showed the conjugate | zygote typically, and the structure of the conjugate | zygote was comprised from the length 6 x width 6 = 36 piece, and showed the joined body which has arrange | positioned two dummy segments in the corner part of a ground plane. FIG. It is the figure which showed the conjugate | zygote typically, and is the figure which showed the conjugate | zygote which the structure of the conjugate | zygote was comprised from 7 vertical x 7 horizontal = 36 pieces, and has arrange | positioned the dummy segment in the corner part of a ground plane. is there. It is the figure which showed the conjugate | zygote typically, and is the figure which showed the conjugate | zygote which the structure of the conjugate | zygote was comprised from 8 vertical x 8 horizontal = 64, and has arrange | positioned the dummy segment in the corner part of a ground plane. is there. It is the figure which showed the conjugate | zygote typically, and is the figure which showed the conjugate | zygote which the structure of the conjugate | zygote was comprised from 6 vertical x 6 horizontal = 36 pieces, and has arranged four dummy segments in four corners. It is. It is the figure which showed the conjugate | zygote typically, and is the figure which showed the conjugate | zygote which the structure of a conjugate | zygote was comprised from 7 vertical x 7 horizontal = 49 pieces, and has arranged four dummy segments in four corners. It is. It is the figure which showed the conjugate | zygote typically, and is the figure which showed the conjugate | zygote which the structure of a conjugate | zygote was comprised from 8 vertical x 8 horizontal = 64, and arrange | positioned four dummy segments in four corners. It is. It is a schematic diagram of a joined honeycomb segment when no segment is arranged at a corner. FIG. 3 is a schematic diagram of a joined honeycomb segment assembly showing a state of pressurization when no segment is arranged at a corner. It is the schematic diagram which showed the honeycomb segment bonded body which removed the dummy segment from the corner part. It is the schematic diagram which showed the honeycomb segment bonded body which removed the dummy segment from the corner part. It is the schematic diagram which showed the honeycomb segment bonded body which removed the dummy segment from the corner part. FIG. 5 is a schematic view showing a joined body in which dummy segments are arranged on the ground surface side and honeycomb segments and dummy segments are not arranged in corners located on the side opposite to the ground surface. FIG. 3 is a schematic view showing a joined body in which dummy segments are arranged on the ground surface side and honeycomb segments are arranged at corners located on the side opposite to the ground surface. It is a perspective schematic diagram showing an example of a honeycomb structure. It is a perspective schematic diagram of a honeycomb segment. It is the sectional view on the AA line in FIG. It is the schematic diagram which showed typically the shape of the number of sets 6 length x 6 width shown in Table 1. It is the schematic diagram which showed the shape of the number of sets shown by Table 1 of the segment body 7 vertical x 7 horizontal. It is the schematic diagram which showed the shape of the number of groups shown by Table 1 length 8 piece * width 8 segment body. It is the figure which showed the measurement of the joining width inside a dummy segment, and is the schematic diagram shown typically. It is the figure which showed the measurement of the joining width of the exterior of a dummy segment, and is the schematic diagram shown typically.

Explanation of symbols

1, 1A, 1B, 1C, 1D, 1F, 1G: joined body, 2: honeycomb segment joined body, 3, 3c, 3d: honeycomb segment, 4: joined material, 4c, 4d: joined surface, 4S: joined material layer 5, 5a, 5b, 5c, 5d, 5e, 5f, 5g, 5h, 5i, 5j, 5k, 5l, 5m, 5n, 5p, 5q, 5r, 5s, 5t, 5u, 5v, 5w: dummy segment, 6, 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h, 6i, 6j, 6k, 6l, 6m, 6n, 6p, 6q, 6r, 6s, 6t, 6u, 6v, 6w, 6x, 6y: Corners, 8, 8a, 8b: Pressurizing cylinders, 9, 9a, 9b: Pressurizing reference planes, X ₁ , X _2, X ₃ , X ₄ , X ₅ , X ₆ : Rows of honeycomb segments (honeycomb segments Group), 11: partition, 12: cell, 13: coaty Ingredients, 14: filler, H: honeycomb structure, P: Point.

Claims (4)

A method for manufacturing a honeycomb structure made of ceramics, comprising a joining step of integrating a plurality of honeycomb segments having a plurality of cells that are partitioned by partition walls and penetrate in the axial direction by joining with a joining material,
A method for producing a joined honeycomb segment using a recyclable dummy segment instead of a honeycomb segment at any corner,
The joining step is a step of obtaining a joined body obtained by joining the honeycomb segment and the dummy segment,
After the joining step, the method has a drying step of drying the obtained joined body,
Further, after the drying step, only the dummy segment is removed, and a honeycomb segment bonded body manufacturing method for manufacturing a honeycomb segment bonded body ,
A method for producing a bonded honeycomb segment, wherein the dummy segment has a compressive elastic modulus of 2.0 to 10 GPa and the dummy segment has a heat resistant temperature of 120 ° C or higher .   The method for manufacturing a bonded honeycomb segment according to claim 1, wherein the drying step is performed after the pressing step of adjusting the bonding width by further pressing the bonded body obtained in the bonding step.   The method for manufacturing a joined honeycomb segment according to claim 1 or 2, wherein the dummy segment is used at least in a corner portion in contact with the ground contact surface.   The method for manufacturing a joined honeycomb segment according to any one of claims 1 to 3, wherein the dummy segments are used at all corners.

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