Centering sealing method for connecting pipeline of diesel engine exhaust system

Abstract

The invention discloses a centering sealing method for a connecting pipeline of a diesel engine exhaust system, which belongs to the technical field of diesel engine exhaust systems and comprises the following steps of: S1, centering and mounting a pulse converter on a flywheel shell; s2, a positioning sleeve and a measuring gauge are installed on the left side and the right side of the connecting pipeline correspondingly to replace the conical sealing ring with the standard thickness, wherein the positioning sleeve and the measuring gauge are each of a disc structure with one side provided with a connecting end; s3, judging and selecting the thickness specification of the conical sealing ring required by each joint in the connecting pipeline; and S4, the positioning sleeve and the measuring gauge are disassembled, and the conical sealing ring with the thickness specification selected in the step S3 is installed at the corresponding position. In the installation process, the proper conical sealing ring can be judged and selected rapidly according to the gap distance between the exhaust bent pipe and the exhaust main pipe and the gap distance between the exhaust bent pipe and the pulse converter and the centering condition, the sealing centering performance of all connecting positions of connecting pipelines is guaranteed, and operation is convenient and rapid.

Description

Technical Field

[0001] The invention belongs to the technical field of diesel engine exhaust systems, and in particular relates to a centering and sealing method for connecting pipes of a diesel engine exhaust system. Background Art

[0002] like Figure 1 As shown, the connecting pipeline of the diesel engine exhaust system includes a pulse converter 4 installed on the threaded hole of the flywheel housing and two exhaust main pipes 1 connected to the connecting ports on the left and right sides of the pulse converter 4 through two exhaust elbows 3, wherein the connection between the exhaust elbow 3 and the pulse converter 4 and the exhaust main pipe 1 is sealed by a conical sealing ring 2 and is clamped and fixed by a clamping flange 7, as shown in FIG. Figure 2 As shown, the conical sealing ring 2 includes an integrally formed conical end and a flat end. When sealing, the conical end of the conical sealing ring 2 is inserted into the port of the exhaust elbow 3 for sealing, while the exhaust manifold 1 and the pulse converter 4 are sealed through the flat end of the conical sealing ring 2. Due to processing and assembly errors, the conical sealing ring 2 has different specifications. Therefore, when faced with the selection of the specifications of the conical sealing ring 2, the operator needs to spend a lot of time to select the conical sealing ring 2 that is suitable for the connection of each component of the connecting pipeline, which is time-consuming and labor-intensive, and delays the installation progress. Therefore, under normal circumstances, the operator basically does not select the specifications of the conical sealing ring 2 during the assembly process of the connecting pipeline, and only uses the conical sealing ring 2 of the middle standard thickness for installation. However, this operation method does not allow any gaps visible to the naked eye during installation, and the operator needs to judge with the naked eye based on the fit of the sealing surface. Therefore, it is subjective and has poor consistency. It is easy for the conical sealing ring 2 to be misaligned or have a poor fit after tightening, and smoke leakage is very likely to occur during use. In addition, this method requires high processing accuracy for the three components of the exhaust main pipe 1, the exhaust elbow 3, and the pulse converter 4, and has poor applicability and flexibility, which undoubtedly increases the difficulty of assembly.

[0003] Therefore, a method for centering and sealing the connecting pipes of a diesel engine exhaust system is now needed, which can conveniently and quickly realize the sealing and centering of each connection point of the connecting pipe. Summary of the invention

[0004] The purpose of the present invention is to provide a method for centering and sealing the connecting pipes of a diesel engine exhaust system, which can quickly select a suitable conical sealing ring according to the gap distance and centering conditions between the exhaust elbow pipe, the exhaust main pipe and the pulse converter during the installation process to ensure the sealing centering of each connection point of the connecting pipe. The operation is convenient and fast, and the installation time between the various components of the entire connecting pipe can be effectively saved, and the operating efficiency can be improved. At the same time, the assembly difficulty of the three components of the exhaust main pipe, the exhaust elbow pipe and the pulse converter can be effectively reduced.

[0005] To achieve the above purpose, the technical solution adopted by the present invention is: A method for centering and sealing a connecting pipe of a diesel engine exhaust system comprises the following steps: Step S1: center and install the pulse converter on the flywheel housing; Step S2: installing a positioning sleeve and a measuring gauge on the left and right sides of the connecting pipeline respectively so that the two replace the conical sealing ring of standard thickness, wherein the positioning sleeve and the measuring gauge are both disc structures with a connecting end on one side: during installation, firstly install the disc of the positioning sleeve on the connecting port of the pulse converter, and at the same time insert the connecting end of the measuring gauge into one end of the exhaust main pipe, and then plug one end of the exhaust elbow into the connecting end of the positioning sleeve, and finally press along the bending direction of the exhaust elbow so that the other end of the exhaust elbow abuts against the disc of the measuring gauge; Step S3: Determine and select the thickness specifications of the conical sealing rings required at each connection in the connecting pipeline: by determining the offset and warping of the exhaust elbow pipe opening on the disc of the measuring gauge, select the thickness specifications of the conical sealing rings required between the exhaust elbow pipes and the pulse converter and the exhaust manifold on the left and right sides of the connecting pipeline. The thickness specifications of the conical sealing rings include low thickness and high thickness in addition to the standard thickness. Step S4: Install the conical sealing ring: remove the positioning sleeves and measuring gauges between the left and right exhaust elbows and the pulse converter and the exhaust main pipe respectively, and install the conical sealing rings of the thickness selected in step S3 at the corresponding positions to complete the centering seal.

[0006] A further improvement of the technical solution of the present invention is that in step S2, the thickness of the discs of the positioning sleeve and the measuring gauge are the same as the thickness of the plane end of the conical sealing ring of standard thickness.

[0007] A further improvement of the technical solution of the present invention is that the disc of the measuring gauge is a graduated disc, a plurality of reference lines are concentrically arranged on the disc surface, and the plurality of reference lines are respectively adapted to exhaust elbows of different calibers.

[0008] A further improvement of the technical solution of the present invention is that in step S3, when judging the thickness specification of the conical sealing ring required between the left and right exhaust bends and the pulse converter, the offset of the pipe openings of the left and right exhaust bends relative to the corresponding reference line on the dial is observed respectively.

[0009] A further improvement of the technical solution of the present invention is that: based on the reference line on the dial, when the pipe opening of the left exhaust bend pipe is offset to the left or the pipe opening of the right exhaust bend pipe is offset to the right, a conical sealing ring with a low thickness is selected; when the pipe opening of the left exhaust bend pipe is offset to the right or the pipe opening of the right exhaust bend pipe is offset to the left, a conical sealing ring with a high thickness is selected; when the exhaust bend pipes on both sides are not offset, a conical sealing ring with a standard thickness is selected.

[0010] A further improvement of the technical solution of the present invention is that in step S3, when judging the thickness specification of the conical sealing ring required between the left and right exhaust elbows and the exhaust main pipe, the warping of the pipe openings of the left and right exhaust elbows on the dial surface is observed respectively.

[0011] A further improvement of the technical solution of the present invention is that: based on the surface of the dial, when the left side of the pipe opening of the left exhaust bend pipe is tilted or the right side of the pipe opening of the right exhaust bend pipe is tilted, a low-thickness conical sealing ring is selected; when the right side of the pipe opening of the left exhaust bend pipe is tilted or the left side of the pipe opening of the right exhaust bend pipe is tilted, a high-thickness conical sealing ring is selected; when the exhaust bends on both sides are not tilted, a standard-thickness conical sealing ring is selected.

[0012] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is: The centering and sealing method for the connecting pipe of the exhaust system of a diesel engine of the present invention can quickly select a conical sealing ring of appropriate specifications according to the gap distance and centering conditions between the exhaust elbow pipe, the exhaust main pipe and the pulse converter during the installation process, thereby ensuring the sealing centering of each connection point of the connecting pipe. The operation is convenient and fast, and can effectively save the installation time between the various components of the entire connecting pipe, improve the operating efficiency, and at the same time effectively reduce the difficulty of assembling the three components of the exhaust main pipe, the exhaust elbow pipe and the pulse converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a top view assembly diagram of the exhaust system connecting pipe in the background technology of the present invention; Figure 2 It is an assembly diagram of a conical sealing ring and an exhaust elbow in the background technology of the present invention; Figure 3 It is a top view assembly diagram of the measuring gauge and the positioning sleeve during the centering and sealing operation of the present invention; Figure 4 It is a schematic diagram of the structure of the measuring gauge in the present invention; Figure 5 It is a side view assembly diagram of the left exhaust elbow, the measuring gauge and the positioning sleeve in the present invention; Figure 6 It is a partial enlarged view of point A when judging the offset of the left exhaust elbow by a measuring gauge in the present invention; Figure 7 It is a partial enlarged view of point A when judging the tilting condition of the left exhaust elbow pipe by a measuring gauge in the present invention; Among them, 1. exhaust main pipe, 2. conical sealing ring, 3. exhaust elbow, 4. pulse converter, 5. positioning sleeve, 6. measuring gauge, 6-1. dial, 6-2. reference line, 7. clamping flange. DETAILED DESCRIPTION

[0014] The present invention is further described in detail below in conjunction with embodiments: like Figure 3-Figure 7 As shown, the present invention provides a method for centering and sealing a connecting pipe of a diesel engine exhaust system, which specifically includes the following steps: Step S1: center and install the pulse converter 4 on the flywheel housing; Specifically, the pulse converter 4 and the flywheel housing are respectively provided with four symmetrical threaded holes. First, two plug-in positioning devices are sequentially inserted into the two groups of threaded holes on the pulse converter 4 and the flywheel housing, so as to center the pulse converter 4 on the flywheel housing. Then, two fastening bolts are installed in the two groups of threaded holes below the pulse converter 4 and the flywheel housing, and tightened at a torque of 35 Nm. Finally, the two plug-in positioning devices are disassembled, and the other two fastening bolts are installed in the two groups of threaded holes above the pulse converter 4 and the flywheel housing, and tightened at a torque of 35 Nm. Preferably, the plug-in positioning device adopts a latch or other pin structure with a positioning function. Step S2: installing the positioning sleeve 5 and the measuring gauge 6 on the left and right sides of the connecting pipeline respectively, so that the two replace the conical sealing ring 2 of standard thickness; Specifically, Figure 3 As shown, the positioning sleeve 5 and the measuring gauge 6 are both customized parts, and both are disc structures with a connecting end on one side. The thickness of the discs of the positioning sleeve 5 and the measuring gauge 6 is the same as the thickness of the plane end of the conical sealing ring 2 of standard thickness, wherein the connecting end of the positioning sleeve 5 is adapted to the inner wall of the pipe opening of the exhaust elbow 3, the disc of the positioning sleeve 5 is adapted to the connecting port on the pulse converter 4, the connecting end of the measuring gauge 6 is adapted to the inner wall of the pipe opening of the exhaust main pipe 1, and the disc of the measuring gauge 6 is adapted to the pipe opening of the exhaust elbow 3, as shown in FIG. Figure 4 As shown, the disc of the measuring gauge 6 adopts a graduated disc 6-1, and a plurality of reference lines 6-2 are concentrically arranged on the disc surface, that is, the plurality of reference lines 6-2 are a plurality of concentric circles, which can be respectively adapted to exhaust elbows 3 of different calibers. When the pipe mouth of the exhaust elbow 3 is centered and abutted on the graduated disc 6-1, the corresponding reference line 6-2 is just located at the outer periphery of the pipe mouth. Therefore, the measuring gauge 6 can be applied to exhaust elbows 3 of various calibers, and has higher applicability and versatility. In order to better identify each reference line 6-2, the same or different paints can be applied on each reference line 6-2 to distinguish them. Preferably, the innermost reference line 6-2 is painted blue, and the other reference lines 6-2 are painted yellow. Usually, the exhaust elbow 3 applicable to the innermost reference line 6-2 is more commonly used in daily life. The method of installing the positioning sleeve 5 and the measuring gauge 6 on the left and right sides of the connecting pipeline is as follows: like Figure 3 and Figure 5As shown, firstly, the disc of the positioning sleeve 5 is installed on the connecting port of the pulse converter 4, and at the same time, the connecting end of the measuring gauge 6 is inserted into one end of the exhaust manifold 1, and then one end of the exhaust elbow 3 is plugged into the connecting end of the positioning sleeve 5, and finally, the exhaust elbow 3 is pressed along the bending direction so that the other end of the exhaust elbow 3 abuts against the disc of the measuring gauge 6, that is, abuts against the scale plate 6-1 of the measuring gauge 6; According to the above method, two exhaust elbows 3 are respectively installed on the connection ports on the left and right sides of the pulse converter 4 through the positioning sleeve 5 and the measuring gauge 6, and are respectively connected to the exhaust main pipes 1 on the left and right sides, so that the positioning sleeve 5 and the measuring gauge 6 replace the standard thickness conical sealing ring 2 at the corresponding position; Step S3: determining and selecting the thickness specification of the conical sealing ring 2 required for each connection in the connecting pipeline; Specifically, by judging the offset and warping of the exhaust elbow 3 on the disc of the measuring gauge 6, i.e., the scale plate 6-1, the thickness specification of the conical sealing ring 2 required between the exhaust elbow 3 and the pulse converter 4 and the exhaust manifold 1 on the left and right sides of the connecting pipeline is selected. The thickness specification of the conical sealing ring 2 includes low thickness and high thickness in addition to the standard thickness. The low thickness and high thickness are relative to the standard thickness, i.e., the low thickness is thinner than the standard thickness, and the high thickness is thicker than the standard thickness. When judging the thickness specification of the conical sealing ring 2 required between the left and right exhaust elbows 3 and the pulse converter 4, respectively observe the offset of the pipe openings of the left and right exhaust elbows 3 on the scale plate 6-1, that is, the offset of the pipe openings of the exhaust elbows 3 relative to the corresponding reference line 6-2. When the pipe opening of the exhaust elbow 3 is in the centered state on the scale plate 6-1, the corresponding reference line 6-2 is exactly located at the outer periphery of the pipe opening; like Figure 6 As shown, when making a judgment, based on the reference line 6-2 on the scale plate 6-1, when the pipe opening of the left exhaust bend 3 deviates to the left or the pipe opening of the right exhaust bend 3 deviates to the right, it proves that the disc of the positioning sleeve 5 replacing the standard thickness conical sealing ring 2 between the exhaust bend 3 and the pulse converter 4 is too thick, so a conical sealing ring 2 with a low thickness should be selected on this side; when the pipe opening of the left exhaust bend 3 deviates to the right or the pipe opening of the right exhaust bend 3 deviates to the left, it proves that the disc of the positioning sleeve 5 replacing the standard thickness conical sealing ring 2 between the exhaust bend 3 and the pulse converter 4 is too thin, so a conical sealing ring 2 with a high thickness should be selected on this side; when the exhaust bend 3 on both sides is not deviated, it proves that the disc of the positioning sleeve 5 replacing the standard thickness conical sealing ring 2 between the exhaust bend 3 and the pulse converter 4 is just suitable, so a conical sealing ring 2 with a standard thickness should be selected on this side; When judging the thickness specification of the conical sealing ring 2 required between the left and right exhaust elbows 3 and the exhaust manifold 1, observe the warping of the pipe openings of the left and right exhaust elbows 3 on the dial 6-1 respectively; like Figure 7 As shown, when making a judgment, based on the surface of the dial 6-1, when the left side of the pipe opening of the left exhaust bend pipe 3 is tilted or the right side of the pipe opening of the right exhaust bend pipe 3 is tilted, it proves that the dial 6-1 of the measuring gauge 6 for replacing the standard thickness conical sealing ring 2 between the exhaust bend pipe 3 and the exhaust main pipe 1 is too thick, so a conical sealing ring 2 with a low thickness should be selected on this side; when the right side of the pipe opening of the left exhaust bend pipe 3 is tilted or the left side of the pipe opening of the right exhaust bend pipe 3 is tilted, it proves that the dial 6-1 of the measuring gauge 6 for replacing the standard thickness conical sealing ring 2 between the exhaust bend pipe 3 and the exhaust main pipe 1 is too thin, so a conical sealing ring 2 with a high thickness should be selected on this side; when the exhaust bend pipes 3 on both sides are not tilted, it proves that the dial 6-1 of the measuring gauge 6 for replacing the standard thickness conical sealing ring 2 between the exhaust bend pipe 3 and the exhaust main pipe 1 is just suitable, so a conical sealing ring 2 with a standard thickness should be selected on this side; Step S4: Installing the conical sealing ring 2: Dismantle the positioning sleeve 5 and the measuring gauge 6 between the exhaust elbow 3 and the pulse converter 4 on the left and right sides and the exhaust manifold 1, and install the conical sealing ring 2 of the thickness specification selected in step S3 at the corresponding position to complete the centering seal; During installation, manual connections must be made in sequence. First, use a torque wrench to alternately tighten the nuts on the compression flange 7 at the connection between the exhaust elbow 3 and the pulse converter 4 to 65 Nm. Then use a torque wrench to alternately tighten the nuts or bolts on the compression flange 7 at the connection between the exhaust elbow 3 and the exhaust manifold 1 to 65 Nm. Finally, tighten the fixing bolts of the exhaust manifold 1 and the cylinder head with a torque of 65 Nm.

[0015] The present invention can quickly select a tapered sealing ring 2 of appropriate specifications according to the gap distance and alignment between the exhaust elbow 3 and the exhaust main pipe 1 and the pulse converter 4 during the installation process, thereby ensuring the sealing alignment of each connection point of the connecting pipeline. The operation is convenient and quick, and can effectively save the installation time between the various components of the entire connecting pipeline, improve the operating efficiency, and at the same time effectively reduce the assembly difficulty of the three components of the exhaust main pipe 1, the exhaust elbow 3 and the pulse converter 4.

[0016] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A method for centering and sealing a connecting pipe of a diesel engine exhaust system, Features The following steps are involved: Step S1: centering and installing the pulse converter (4) on the flywheel housing; Step S2: installing a positioning sleeve (5) and a measuring gauge (6) on the left and right sides of the connecting pipeline respectively so that the two replace the conical sealing ring (2) of standard thickness, wherein the positioning sleeve (5) and the measuring gauge (6) are both disc structures with a connecting end provided on one side: during installation, firstly, the disc of the positioning sleeve (5) is installed on the connecting port of the pulse converter (4), and at the same time, the connecting end of the measuring gauge (6) is inserted into one end of the exhaust main pipe (1), and then one end of the exhaust elbow (3) is plugged into the connecting end of the positioning sleeve (5), and finally, the exhaust elbow (3) is pressed along the bending direction so that the other end of the exhaust elbow (3) abuts against the disc of the measuring gauge (6); Step S3: Determine and select the thickness specifications of the conical sealing ring (2) required for each connection in the connecting pipeline: by determining the offset and warping of the exhaust elbow (3) on the disc of the measuring gauge (6), select the thickness specifications of the conical sealing ring (2) required between the exhaust elbow (3) and the pulse converter (4) and the exhaust main pipe (1) on the left and right sides of the connecting pipeline. The thickness specifications of the conical sealing ring (2) include low thickness and high thickness in addition to the standard thickness; Step S4: Install the conical sealing ring (2): Remove the positioning sleeve (5) and the measuring gauge (6) between the left and right exhaust elbows (3) and the pulse converter (4) and the exhaust main pipe (1), and install the conical sealing ring (2) of the thickness specification selected in step S3 at the corresponding position to complete the centering seal.

2. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 1, Features: In step S2, the thickness of the discs of the positioning sleeve (5) and the measuring gauge (6) are the same as the thickness of the plane end of the conical sealing ring (2) of standard thickness.

3. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 2, Features: The circular disk of the measuring gauge (6) is a graduated disk (6-1), and a plurality of reference lines (6-2) are concentrically arranged on the disk surface, and the plurality of reference lines (6-2) are respectively adapted to exhaust elbows (3) of different calibers.

4. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 3, Features: In step S3, when determining the thickness specifications of the conical sealing ring (2) required between the left and right exhaust bends (3) and the pulse converter (4), the offset of the pipe openings of the left and right exhaust bends (3) relative to the corresponding reference lines (6-2) on the scale plate (6-1) is observed respectively.

5. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 4, Features: Based on the reference line (6-2) on the scale plate (6-1), when the pipe opening of the left exhaust bend pipe (3) is offset to the left or the pipe opening of the right exhaust bend pipe (3) is offset to the right, a conical sealing ring (2) with a low thickness is selected; when the pipe opening of the left exhaust bend pipe (3) is offset to the right or the pipe opening of the right exhaust bend pipe (3) is offset to the left, a conical sealing ring (2) with a high thickness is selected; when the exhaust bend pipes (3) on both sides are not offset, a conical sealing ring (2) with a standard thickness is selected.

6. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 3, Features: In step S3, when determining the thickness specification of the conical sealing ring (2) required between the left and right exhaust elbows (3) and the exhaust main pipe (1), the warping conditions of the pipe openings of the left and right exhaust elbows (3) on the surface of the scale plate (6-1) are respectively observed.

7. A method for centering and sealing a connecting pipe of a diesel engine exhaust system according to claim 6, Features: Based on the surface of the scale plate (6-1), when the left side of the pipe opening of the left exhaust bend pipe (3) is tilted or the right side of the pipe opening of the right exhaust bend pipe (3) is tilted, a tapered sealing ring (2) with a low thickness is selected; when the right side of the pipe opening of the left exhaust bend pipe (3) is tilted or the left side of the pipe opening of the right exhaust bend pipe (3) is tilted, a tapered sealing ring (2) with a high thickness is selected; when the exhaust bend pipes (3) on both sides are not tilted, a tapered sealing ring (2) with a standard thickness is selected.

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