Heat shield cover and its processing method, high-temperature fluid passage, exhaust system, vehicle

Abstract

To provide a heat insulating cover.SOLUTION: This invention relates to a heat insulating cover, a processing method thereof, a high temperature fluid passage, an exhaust system and a vehicle. The heat insulating cover includes a first axial segment and a second axial segment axially connected to the first axial segment. An axial end of the first axial segment and an axial end of the second axial segment constitute a pressure connection structure in a support segment. In the pressure connection structure, the axial end of the second axial segment presses the axial end of the first axial segment to form a recessed part that can be fitted into an inner cavity of the support segment.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a heat-insulating cover, a processing method thereof, a high-temperature fluid passage, an exhaust system, and a vehicle.

Background Art

[0002] The exhaust system of an engine processes high-temperature exhaust gas generated by the engine with various exhaust members to reduce the emission of pollutants. The various exhaust members can include one or more of pipes, filters, valves, catalysts, mufflers, etc. For example, in the case of a diesel engine, the exhaust member guides exhaust gas through an intake member into a diesel oxidation catalyst (DOC) having an inlet and an outlet. A diesel particulate filter (DPF) can be provided downstream of the diesel oxidation catalyst. Downstream of the diesel oxidation catalyst and any diesel particulate filter is a selective catalytic reduction (SCR) catalyst having an inlet and an outlet, and the outlet passes the exhaust gas to a downstream exhaust member. Taking the DOC as an example, its structure generally includes a passage and a catalyst structure installed in the passage. High-temperature exhaust gas flows into the passage and reacts with the catalyst, reacting hydrocarbons (HC) and carbon monoxide (CO) in the exhaust gas to produce non-polluting water and carbon dioxide.

[0003] Since the temperature of the engine exhaust gas is directly heat-transferred to the exhaust system, the temperature around the exhaust system is usually high, and a heat-insulating member is required to block the heat of the exhaust system from being transferred to surrounding components and prevent the heat from affecting these components. Therefore, it is necessary to provide a heat-insulating cover for the exhaust system and install a heat-insulating material on the outer wall of the passage to achieve a heat-insulating effect.

[0004] In conventional heat shield cover structures, multiple axial segments having an axial length are typically constructed by welding two axially adjacent axial segments together to form the heat shield, or by riveting two axially adjacent axial segments together. However, employing a welding process requires automation and expensive welding robots, while riveting can lead to fatigue life issues. Furthermore, the riveting process also requires high equipment investment and rivet material costs. [Overview of the project]

[0005] The present invention aims to provide a heat-shielding cover.

[0006] The objective of the present invention is to provide a high-temperature fluid passage.

[0007] The objective of the present invention is to provide an exhaust system.

[0008] The objective of this invention is to provide a vehicle.

[0009] The object of the present invention is to provide a method for processing heat-shielding covers.

[0010] A heat shield cover according to one aspect of the present invention includes a first axial segment and a second axial segment axially connected to the first axial segment, wherein the axial end of the first axial segment and the axial end of the second axial segment constitute a pressure connection structure in a support segment, and in the pressure connection structure, the axial end of the second axial segment presses against the axial end of the first axial segment and forms a recess that can be fitted into the internal gap of the support segment.

[0011] In one or more embodiments of the heat shield cover, the thickness of the first axial segment is a first thickness, the thickness of the second axial segment is a second thickness, and the first thickness is smaller than the second thickness.

[0012] In one or more embodiments of the heat shield cover, the overlapping length in the axial direction of the support segment, the axial end of the first axial segment, and the axial end of the second axial segment is shorter than the first length.

[0013] In one or more embodiments of the heat shield cover, the support segment includes an axially adjacent first support ring and a second support ring, the cross-sections of the first support ring and the second support ring each include at least an arc-shaped segment, the internal void is the axial space between the first support ring and the second support ring, the arc-shaped segment is pressed by the axial end of the first axial segment, the axial distance between the first support ring and the second support ring is greater than a first distance, and the height of the recess fitted into the internal void is a first height.

[0014] In one or more embodiments of the heat shield cover, the thickness of the first axial segment is less than 0.3 mm, the thickness of the second axial segment is greater than 0.8 mm, the first length is 50 mm, the first distance is 5 mm, the first height is 4 mm to 6 mm, and the cross-sections of the first support ring and the second support ring are circular.

[0015] A high-temperature fluid passage according to one aspect of the present invention, comprising a passage outer wall, a heat-shielding material layer, and a heat-shielding cover according to any one of the above descriptions, wherein the heat-shielding material layer is filled in the first axial segment, the second axial segment of the heat-shielding cover, and the radial space of the passage outer wall.

[0016] In one or more embodiments of the high-temperature fluid passage, the support segment is welded to the outer wall of the passage.

[0017] In one or more embodiments of the high-temperature fluid passage, the high-temperature fluid passage is used in an exhaust system, the first axial segment corresponds to an intake end cone of the exhaust system, and the second axial segment corresponds to a downstream exhaust member of the intake end cone.

[0018] An exhaust system according to one aspect of the present invention, comprising a high-temperature fluid passage as described in any one of the above, wherein exhaust gas flows through the high-temperature fluid passage and is treated.

[0019] A vehicle according to one aspect of the present invention, comprising an engine and the exhaust system described above, wherein exhaust gas generated by the operation of the engine is processed by the exhaust system.

[0020] A method for processing a heat shield cover according to one aspect of the present invention, comprising: bringing the inner wall surface of a first axial segment having a first axial length into contact with a support segment, wherein the axial length of the first axial segment in contact with the support segment is S1, which is the axial end of the first axial segment; bringing the inner wall surface of a second axial segment having a second axial length into contact with the outer wall surface of the axial end of the first axial segment, wherein the axial length of the second axial segment in contact with the first axial segment is S2, which is the end of the second axial segment; and applying pressure to the outer wall surface of the second axial segment so that the axial end of the second axial segment and the axial end of the first axial segment are pushed into the internal void of the support segment, forming a recess into which they are fitted, thereby forming a pressure connection structure, wherein the first axial segment and the second axial segment are connected axially via the connection of both ends, S3.

[0021] In one or more embodiments of the processing method, in step S3, pressure is applied to the outer wall surface of the second axial segment by profiling tooling using a hydraulic system.

[0022] In one or more embodiments of the processing method, the support segment is welded to the outer wall of the passage wall, the support segment includes at least two axially adjacent support rings, the internal void is the axial space between the two axially adjacent support rings, the thickness of the first axial segment is a first thickness, the thickness of the second axial segment is a second thickness, and the first thickness is smaller than the second thickness.

[0023] In one or more embodiments of the processing method, the thickness of the first axial segment is less than 0.3 mm, the thickness of the second axial segment is greater than 0.8 mm, the overlap length in the axial direction between the first axial segment and the second axial segment is less than 50 mm, the axial distance between the two axially adjacent support rings is greater than 5 mm, the height of the recess is 4 mm to 6 mm, and the cross-section of the support ring is circular.

[0024] Based on the above, the progressive effects of the present invention include, but are not limited to, the following.

[0025] The pressure connection at the axial ends of both the first and second axial segments, and the recessed structure formed by the pressure connection, avoid the need to employ welding or riveting techniques to connect the first and second axial segments of the heat shield cover. Pressure connection can be achieved using relatively small mounting torques, eliminating the need for expensive equipment such as riveting and robotic welding. At the same time, it avoids the fatigue life problems associated with riveting, improving the service life of the heat shield cover and enhancing the reliability of the high-temperature fluid passage, exhaust system, and vehicle that it includes. Furthermore, the adoption of pressure connection and recessed structure can meet the connection needs of thin and thick plates, allowing the use of thin plates where thick plates are not required. This not only reduces the material cost of the heat shield cover but also contributes to the weight reduction of the heat shield cover and the high-temperature fluid passage, exhaust system, and vehicle that it includes.

[0026] The above, as well as other features, properties, and advantages of the present invention, will become more apparent from the following description of the drawings and embodiments. Also, note that the drawings are merely illustrative and not drawn to scale with the actual objects, and further, they should not be used to limit the actual scope of the claims of the present invention.

Brief Description of the Drawings

[0027] [Figure 1] It is a schematic configuration diagram of a high-temperature fluid passage according to an embodiment. [Figure 2] It is a schematic configuration diagram of a pressure connection structure of a heat insulation cover according to an embodiment. [Figure 3] It is a flowchart of a processing method of a heat insulation cover according to an embodiment.

Modes for Carrying Out the Invention

[0028] Various embodiments or examples for implementing the technical solutions of the described subject matter are disclosed below. To simplify the content of this disclosure, specific examples of each element and arrangement are described below, but it should be understood that these are merely examples and do not limit the scope of protection of the present invention. "One embodiment", "an embodiment", and / or "some embodiments" mean certain features, structures, or characteristics related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "one alternative embodiment" mentioned more than twice at different places in this specification does not necessarily refer to the same embodiment. Furthermore, some features, structures, or characteristics in one or more embodiments of the present application can be appropriately combined.

[0029] Vehicles such as automobiles are powered by engines such as diesel engines, and the exhaust gas generated when the engine operates needs to be processed by an exhaust system to meet the requirements of exhaust gas regulations. The above vehicles refer to vehicles in a broad sense, including vehicles, ships, and also working machines such as loaders.

[0030] The engine exhaust system processes the high-temperature exhaust gases generated by the engine using various exhaust components to reduce the emission of pollutants. As shown in Figure 1, the high-temperature fluid passage 100 includes, namely, the intake end cone 10 of the exhaust system and the downstream exhaust components connected thereto, the downstream exhaust components being exemplified by, but not limited to, a diesel oxidation catalyst 20 (DOC). Since the temperature of the engine exhaust gases is directly transferred to the exhaust system, the temperature around the exhaust system is generally high, and a thermal shield assembly is required to block the transfer of heat from the exhaust system to surrounding components and the surrounding environment, thereby preventing these components from being affected by the heat. The thermal shield assembly includes a thermal shield cover 1 and a thermal shield material layer 2, the thermal shield material layer 2 filling the radial space between the outer wall 101 of the intake end cone 10 and the thermal shield cover 1, and the radial space between the outer wall 201 of the diesel oxidation catalyst 20 and the thermal shield cover 1. The heat-shielding material layer 2 may be asbestos, glass fiber, rock wool, silicate, etc., or it may be a vacuum plate. If the heat-shielding requirement is not high, the heat-shielding material layer may be partially made of heat-shielding material and partially filled with air.

[0031] Continuing to refer to Figures 1 and 2, in one embodiment, the heat shield cover 1 includes a first axial segment 11 and a second axial segment 12 axially connected to the first axial segment 11, the material of the first axial segment 11 and the second axial segment 12 being generally stainless steel, for example, 3-series and 4-series stainless steel. The axial end 111 of the first axial segment 11 and the axial end 121 of the second axial segment 12 form a pressure connection structure 13 in the support segment 3. As shown in Figure 1, the first axial segment 11 is installed corresponding to the outer wall 101 of the intake end cone 10, and the heat shield material layer 2 is filled in the radial space between the first axial segment 11 and the outer wall 101 of the intake end cone 10. The second axial segment 12 corresponds to the downstream exhaust member of the intake end cone 10, i.e., the outer wall 201 of the diesel oxidation catalyst 20, and the heat shield material layer 2 is filled in the radial space between the second axial segment 12 and the outer wall 201 of the diesel oxidation catalyst 20. The support segment 3 can be welded to the outer wall 101 of the intake end cone 10 and the outer wall 201 of the diesel oxidation catalyst 20 before pressure connection.

[0032] Continuing to refer to Figures 1 and 2, in the pressure connection structure 13, the axial end 121 of the second axial segment 12 presses against the axial end 111 of the first axial segment 11, and the axial end 121 presses against the axial end 111 to form a recess 131, which can be fitted into the internal gap 30 of the support segment 3. Thus, the axial segments of two axially adjacent heat shield covers are connected by pressure connection. The technology for achieving pressure connection allows a tracing tooling to be installed on the outer surface of the second axial segment 12, and pressure can be applied to the tracing tooling using a hydraulic system. The installation torque can be reduced to 15 N.m, facilitating work production and process quality control. Compared to riveting, which requires specialized equipment and a specialized high-pressure system, adopting the processing process of the solution according to the embodiment is safer, simpler, and more efficient, reducing equipment costs in the case of pressure connection, and at the same time, facilitating automated operation and avoiding the drawback of requiring expensive welding robots in the welding process. At the same time, the fatigue life problem that may exist in riveting is also avoided.

[0033] Continuing to refer to Figure 2, in some embodiments, the above-described pressure connection structure can be used to connect thin plates, particularly thin plates with a thickness of less than 0.3 mm, to thick plates. That is, as shown in Figure 2, the thickness of the first axial segment 11 is the first thickness T1, and the thickness of the second axial segment 12 is the second thickness T2, with the first thickness T1 being smaller than the second thickness T2. This is because, as the inventors have seen from practical experience, in the case of a rivet press connection process, the press holes in the thin plate are destroyed, and therefore, it is difficult to achieve a connection between the first axial segment 11 made of a thin plate and the second axial segment 12 made of a thick plate using a rivet press process. Furthermore, as the inventors have seen from practice, in the case of a welding process, it is difficult to obtain suitable welding parameters for the first axial segment of a thin plate and the second axial segment of a thick plate using an automated welding procedure. The inventors have obtained the above-described pressure connection structure by developing numerous designs, and it is possible to achieve a connection between the first axial segment 11 made of a thin plate and the second axial segment 12 made of a thick plate. This means that thin plates can be used where thick plates are not required, thereby reducing the material cost of the heat shield cover, as well as contributing to the weight reduction of the heat shield cover, the high-temperature fluid passages including it, the exhaust system, and the vehicle. To make it clear, the above-described embodiment is intended to illustrate how the above-described pressure connection structure enables the connection of thin and thick plates, which is difficult to achieve with conventional rivet press connections and automated welding techniques. However, the pressure connection structure of this invention is not limited to the connection of thin and thick plates.

[0034] Continuing to refer to Figures 1 and 2, in some embodiments, the axial overlap length of the support segment 3, the axial end 111 of the first axial segment 11, and the axial end 121 of the second axial segment 12 must be shorter than the length defined as the first length. The beneficial effect of this is to avoid the requirement for equipment that would be excessively high due to the pressure connection, which could cause damage to the thin sheet metal. The specific value of the first length is determined by factors such as the thickness of the first axial segment, the thickness of the second axial segment, and the type of material used, and optionally, the thickness of the first axial segment 11 is less than 0.3 mm, the thickness of the second axial segment 12 is greater than 0.8 mm, and the first length L is 50 mm, i.e., the overlap length is less than 50 mm.

[0035] Continuing to refer to Figures 1 and 2, in one or more embodiments, the specific structure of the support segment 3 includes a first support ring 31 and a second support ring 32, the cross-sections of the first support ring 31 and the second support ring 32 each including at least an arc-shaped segment, for example, the cross-sections shown in Figures 1 and 2 are circular. The dimensions of the first support ring 31 and the second support ring 32 are generally determined according to the thickness of the heat shielding material layer 2, for example, the dimensions of the first support ring 31 and the second support ring 32 in Figure 1 are larger than those of the reinforcing ribs 41 and 42. The internal void 30 of the support segment 3 is the axial space between the two arc-shaped segments, and the beneficial effect of providing the arc-shaped segments is to make the formation of the recess 131 and the deformation due to changes in the structure fitted into the void 30 more gradual, and to reduce stress concentration. The beneficial effects are particularly evident in the case of thin plates, and the inventors have observed from practice that in the pressure connection process, in order to ensure the reliability of the pressure connection, the axial distance between the first support ring 31 and the second support ring 32 must be greater than the distance defined as the first distance D. If the thickness of the first axial segment 11 is less than 0.3 mm and the thickness of the second axial segment 12 is greater than 0.8 mm, then the first distance is 5 mm, meaning that the axial distance between the first support ring 31 and the second support ring 32 must be greater than 5 mm. On the other hand, in order to ensure that the thin plate is not damaged by pressure and to minimize the pressure required for the pressure connection, if the thickness of the first axial segment 11 is less than 0.3 mm and the thickness of the second axial segment 12 is greater than 0.8 mm, it is preferable to limit the height H of the recess 131 to 4 mm to 6 mm in order to ensure connection reliability. Furthermore, although Figure 1 shows a support segment having two support rings, the number of support rings may be greater than two, for example, three, such that the axial distance between adjacent support rings is greater than 5 mm.

[0036] As explained with reference to Figures 1 to 3, in one embodiment, the processing method for the heat shield cover 1 may include the following steps.

[0037] In S1, the inner wall surface 110 of the first axial segment 11, which has a first axial length, is brought into contact with the support segment 3. The axial length at which the first axial segment 11 contacts the support segment 3 is the axial end 111 of the first axial segment 11, and the thickness of the first axial segment 11 is the first thickness T1.

[0038] In S2, the inner wall surface 120 of the second axial segment 12, which has a second axial length, is brought into contact with the outer wall surface of the axial end 111 of the first axial segment 11, and the axial length at which the second axial segment 12 contacts the first axial segment 11 is the end 121 of the second axial segment.

[0039] In step S3, by applying pressure to the outer wall surface 122 of the second axial segment 12, the axial end 121 of the second axial segment 12 and the axial end 111 of the first axial segment 11 are pushed into the internal gap 30 of the support segment 3, forming a recess 131 that fits into this internal gap 30. The axial end 121 of the second axial segment 12 and the axial end 111 of the first axial segment 11 then form a pressure connection structure in the support segment 3, thereby connecting the first axial segment 11 and the second axial segment 12 in the axial direction through the connection of both ends.

[0040] In some embodiments, in S3, a hydraulic system can be used to apply pressure to the outer wall surface 122 of the second axial segment 12 by profiling tooling.

[0041] In some embodiments, the support segment 3 may be an outer wall welded to the passage wall, and the support segment 3 includes at least two axially adjacent support rings, for example, a first support ring 31 and a second support ring 32, and the internal gap 30 is the axial space between the two axially adjacent support rings. The thickness of the first axial segment is a first thickness, and the thickness of the second axial segment is a second thickness, with the first thickness being smaller than the second thickness. In particular, in some embodiments, if the cross-section of the support rings is circular, the thickness of the first axial segment 11 is less than 0.3 mm, and the thickness of the second axial segment 12 is greater than 0.8 mm, the process parameters in S2 and S3 may be such that the axial overlap length of the first axial segment 11 and the second axial segment 12 is less than 50 mm, the axial distance between the two axially adjacent first support rings 31 and the second support rings 32 is greater than 5 mm, and the height of the recess 131 is 4 mm to 6 mm. This prevents damage to the thin first axial segment 11 and ensures the reliability of the pressure connection.

[0042] In short, the beneficial effects of the heat shield cover and its processing method, high-temperature fluid passage, exhaust system, and vehicle provided by the above-described embodiment include, but are not limited to, the following: By using pressure connections at the axial ends of both the first and second axial segments and the recessed structure formed by the pressure connections, it is possible to avoid using welding or rivet press technology to connect the first and second axial segments of the heat shield cover. Pressure connections can be achieved using relatively small mounting torques, eliminating the need to use expensive equipment for rivet press technology and robotic welding technology. At the same time, it avoids the fatigue life problems associated with using rivet press technology, improving the service life of the heat shield cover and enhancing the reliability of the high-temperature fluid passage, exhaust system, and vehicle that include it. Simultaneously, by adopting pressure connections and recessed structures, the need for connecting thin and thick plates can be met, and thin plates can be used where thick plates are not needed. This not only reduces the material cost of the heat shield cover but is also advantageous for reducing the weight of the heat shield cover and the high-temperature fluid passage, exhaust system, and vehicle that include it.

[0043] Although the present invention has been disclosed as described above by the embodiments described above, this does not limit the invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, any modifications, equivalent changes, and modifications made to the above embodiments in accordance with the technical spirit of the invention, without departing from the content of the technical solution of the present invention, should all be included within the scope of the claims of the present invention. [Explanation of Symbols]

[0044] 100-Hot fluid passage 10-Intake End Cone 101 - Outer wall of intake end cone 20-Diesel Oxidation Catalyst 201-Diesel Oxidation Catalyst Exterior Wall 1. Heat-shielding cover 11-First axial segment 111-Axial end of the first axial segment 110 - Inner wall surface of the first axial segment 12 - Second Axis Segment 120 - Inner wall surface of the second axial segment 121 - Axial end of the second axial segment 122 - Exterior wall surface of the second axial segment 2. Heat-shielding material layer 13. Pressure connection structure 131-Recess 3-Support Segment 30-Internal void 31-First support ring 32-Second support ring 41, 42 - Reinforcement ribs

Claims

1. A first axial segment and A second axial segment is axially connected to the first axial segment, A heat-shielding cover comprising, The axial end of the first axial segment and the axial end of the second axial segment constitute a pressure connection structure in the support segment, and in the pressure connection structure, the axial end of the second axial segment presses against the axial end of the first axial segment and forms a recess that can be fitted into the internal gap of the support segment. The thickness of the first axial segment is the first thickness, the thickness of the second axial segment is the second thickness, and the first thickness is smaller than the second thickness. The overlap length in the axial direction of the support segment, the axial end of the first axial segment, and the axial end of the second axial segment is shorter than the first length. A heat shield cover characterized in that the support segment includes an axially adjacent first support ring and a second support ring, the cross-sections of the first support ring and the second support ring each include at least an arc-shaped segment, the internal void is the axial space between the first support ring and the second support ring, the arc-shaped segment is pressed by the axial end of the first axial segment, the axial distance between the first support ring and the second support ring is greater than a first distance, and the height of the recess fitted into the internal void is a first height.

2. The heat shield cover according to claim 1, characterized in that the thickness of the first axial segment is less than 0.3 mm, the thickness of the second axial segment is greater than 0.8 mm, the first length is 50 mm, the first distance is 5 mm, the first height is 4 mm to 6 mm, and the cross-sections of the first support ring and the second support ring are circular.

3. A high-temperature fluid passage comprising a passage outer wall, a heat-shielding material layer, and a heat-shielding cover according to claim 1 or 2, wherein the heat-shielding material layer is filled in the first axial segment, the second axial segment, and the radial space of the passage outer wall of the heat-shielding cover.

4. The high-temperature fluid passage according to claim 3, characterized in that the support segment is welded to the outer wall of the passage.

5. The high-temperature fluid passage according to claim 3, wherein the high-temperature fluid passage is used in an exhaust system, the first axial segment corresponds to the intake end cone of the exhaust system, and the second axial segment corresponds to the downstream exhaust member of the intake end cone.

6. An exhaust system comprising a high-temperature fluid passage as described in claim 3, wherein exhaust gas flows through the high-temperature fluid passage and is treated.

7. A vehicle comprising an engine and an exhaust system according to claim 6, wherein exhaust gases generated by the operation of the engine are processed by the exhaust system.

8. A method for processing a heat-shielding cover, The inner wall surface of a first axial segment having a first axial length is brought into contact with a support segment, and the axial length at which the first axial segment contacts the support segment is S1, which is the axial end of the first axial segment, The inner wall surface of a second axial segment having a second axial length is brought into contact with the outer wall surface of the axial end of the first axial segment, and the axial length at which the second axial segment contacts the first axial segment is S2, which is the end of the second axial segment. By applying pressure to the outer wall surface of the second axial segment, the axial end of the second axial segment and the axial end of the first axial segment are pushed into the internal gap of the support segment, forming recesses into which they are fitted, thus constituting a pressure connection structure. The first axial segment and the second axial segment are connected axially via connections at both ends, including S3. A method for processing a heat shield cover, characterized in that the support segment is welded to the outer wall of the passageway wall, the support segment includes at least two axially adjacent support rings, the internal void is the axial space between the two axially adjacent support rings, the thickness of the first axial segment is a first thickness, the thickness of the second axial segment is a second thickness, and the first thickness is smaller than the second thickness.

9. The machining method according to claim 8, characterized in that, in S3, pressure is applied to the outer wall surface of the second axial segment by tracing tooling using a hydraulic system.

10. The machining method according to claim 8, characterized in that the thickness of the first axial segment is less than 0.3 mm, the thickness of the second axial segment is greater than 0.8 mm, the overlap length in the axial direction between the first axial segment and the second axial segment is less than 50 mm, the axial distance between the two axially adjacent support rings is greater than 5 mm, the height of the recess is 4 mm to 6 mm, and the cross-section of the support ring is circular.

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