Large gas engine exhaust pipe
By welding the exhaust manifold and bellows together, and using sealing rings and coatings at the flange connection, combined with the design of the guide plate and the flow channel, the problem of air leakage in the engine exhaust pipe was solved, improving the reliability and efficiency of the engine.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GUANGXI YUCHAI MARINE & GENSET POWER CO LTD
- Filing Date
- 2025-06-30
- Publication Date
- 2026-05-05
AI Technical Summary
The existing connection method of engine exhaust pipe is prone to air leakage, which leads to a decrease in engine reliability and efficiency.
The exhaust manifold and bellows are fixedly connected by welding, and sealing rings and coatings are used at the flange connection. Combined with the design of guide plates and diversion channels, the sealing performance and flow efficiency are improved.
It effectively reduces the risk of air leakage, improves engine reliability and efficiency, extends service life, reduces emissions, and improves environmental protection efficiency.
Smart Images
Figure CN224200723U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of engine exhaust technology, and more specifically, to an exhaust pipe for a large gas engine. Background Technology
[0002] Currently, engine exhaust pipes play a crucial role in various internal combustion engine equipment such as automobiles, motorcycles, ships, and generator sets, responsible for expelling the exhaust gases after combustion in gas engines.
[0003] Common exhaust pipe connection methods often employ a single-cylinder or multi-cylinder casting + bellows + clamp connection scheme. This connection method is relatively simple, and the bellows also provides some compensation. The connection is simple and easy to disassemble the exhaust pipe. However, exhaust pipes with detachable connections are prone to poor sealing at the joints, leading to air leakage. Furthermore, the engine exhaust pipe is a high-temperature component, and the exhaust pipe and clamp are prone to deformation and air leakage after long-term operation at high temperatures. This can result in insufficient engine boost capacity, thereby affecting engine reliability, engine thermal efficiency, and unit electrical efficiency. Utility Model Content
[0004] The technical problem to be solved by this utility model is to address the above-mentioned shortcomings of the prior art by providing a large gas engine exhaust pipe in which the exhaust branch pipe and the corrugated pipe are fixedly connected by welding, which can effectively reduce the risk of air leakage and effectively improve the reliability of the engine.
[0005] The technical solution of this utility model is as follows: a large gas engine exhaust pipe, including a first exhaust pipe and a second exhaust pipe, both of which include multiple exhaust manifolds and corrugated pipes. Each exhaust manifold and corrugated pipe segment of the first and second exhaust pipes is fixed by welding. The first exhaust pipe has a first connecting flange and a second connecting flange at both ends, and the second exhaust pipe has a third connecting flange at one end and a cover plate at the other end. The second connecting flange and the third connecting flange are connected by bolts. Each exhaust manifold segment is provided with an exhaust manifold that communicates with it. The other end of the exhaust manifold is provided with a fourth connecting flange, which is bolted to the engine cylinder head. Each exhaust manifold segment is provided with at least one fixing bracket.
[0006] As a further improvement, the inner walls of the exhaust manifold, the first exhaust pipe, and the second exhaust pipe are all coated.
[0007] Furthermore, the second connecting flange and the third connecting flange are connected by bolts. The second connecting flange is provided with a countersunk groove, and the third connecting flange is provided with an annular protrusion adapted to the countersunk groove. The annular protrusion is movably inserted into the countersunk groove.
[0008] Furthermore, a sealing ring is provided between the second connecting flange and the third connecting flange.
[0009] Furthermore, the inner diameter of the exhaust manifold gradually increases along the airflow direction.
[0010] Furthermore, the exhaust manifold is provided with a rounded bend section.
[0011] Furthermore, a guide plate is provided at the connection point between the exhaust manifold and the first exhaust pipe or the second exhaust pipe, and the guide plate extends into the first exhaust pipe or the second exhaust pipe along the tangential direction at the intersection of the exhaust manifold and the first exhaust pipe or the second exhaust pipe.
[0012] Furthermore, the fourth connecting flange is provided with a flow divider groove, which has an elongated waist-shaped structure, and the width of the flow divider groove is adapted to the inner diameter of the exhaust manifold. The flow divider groove is connected to the engine air intake.
[0013] Furthermore, an arc-shaped guide plate is provided on the arc-shaped sidewall of the diversion channel away from the exhaust manifold.
[0014] Beneficial effects
[0015] Compared with the prior art, this utility model has the following advantages:
[0016] This utility model discloses a large gas engine exhaust pipe, in which the exhaust branch pipe and the corrugated pipe are fixedly connected by welding, and the first exhaust pipe and the second exhaust pipe are connected by flanges. By minimizing the detachable connection in the engine exhaust pipe, the risk of air leakage can be effectively reduced and the reliability of the engine can be effectively improved. Attached Figure Description
[0017] Figure 1 This is a three-dimensional structural diagram of the present invention;
[0018] Figure 2 This is a schematic diagram of the main structure of the first exhaust pipe in this utility model;
[0019] Figure 3 This is a schematic diagram of the main structure of the second exhaust pipe in this utility model;
[0020] Figure 4 This is a schematic diagram of the front view of the first or second exhaust pipe in this utility model.
[0021] Figure 5 This is a side view cross-sectional structural diagram of the first or second exhaust pipe in this utility model;
[0022] Figure 6This is a cross-sectional structural diagram of the second and third connecting flanges in this utility model;
[0023] Figure 7 This is a three-dimensional structural diagram of the fourth connecting flange in this utility model;
[0024] Figure 8 This is a cross-sectional structural diagram of the fourth connecting flange in this utility model.
[0025] Wherein: 1-First exhaust pipe, 2-Second exhaust pipe, 3-Exhaust branch pipe, 4-First connecting flange, 5-Second connecting flange, 6-Third connecting flange, 7-Cover plate, 8-Exhaust manifold, 9-Fixing bracket, 10-Belled pipe, 11-Fourth connecting flange, 12-Rounded corner bend, 13-Guide plate, 14-Sink, 15-Annular protrusion, 16-Diverter groove, 17-Arc-shaped guide plate. Detailed Implementation
[0026] The present invention will be further described below with reference to specific embodiments shown in the accompanying drawings.
[0027] See Figure 1-8 A large gas engine exhaust pipe includes a first exhaust pipe 1 and a second exhaust pipe 2. Both the first exhaust pipe 1 and the second exhaust pipe 2 include multiple exhaust manifolds 3 and corrugated pipes 10. Each exhaust manifold 3 and corrugated pipe 10 of the first exhaust pipe 1 and the second exhaust pipe 2 are fixed together by welding. The first exhaust pipe 1 has a first connecting flange 4 and a second connecting flange 5 at both ends. The first connecting flange 4 can be connected to the turbocharger of the engine. The second exhaust pipe 2 has a third connecting flange 6 at one end and a cover plate 7 at the other end. The second connecting flange 5 and the third connecting flange 6 are connected by bolts. Each exhaust manifold 3 is provided with an exhaust manifold 8 that communicates with it. The other end of the exhaust manifold 8 is provided with a fourth connecting flange 11, which is bolted to the engine cylinder head. Each exhaust manifold 3 is provided with at least one fixing bracket 9. The number of fixing brackets 9 can be changed according to the number of cylinders of the engine model.
[0028] The exhaust pipe of this large gas engine uses a welded fixed connection between the exhaust branch pipe 3 and the corrugated pipe 10, while the first exhaust pipe 1 and the second exhaust pipe 2 are connected by a flange. By minimizing the number of detachable connections in the engine exhaust pipe, the risk of air leakage can be effectively reduced, and the reliability of the engine can be effectively improved.
[0029] In this embodiment, the inner walls of the exhaust manifold 8, the first exhaust pipe 1, and the second exhaust pipe 2 are all coated with a zirconia ceramic layer. The zirconia ceramic coating has excellent high temperature resistance and heat insulation properties, and can remain stable in high temperature environments, which can effectively extend the service life of the exhaust manifold 8, the first exhaust pipe 1, and the second exhaust pipe 2.
[0030] In this embodiment, the second connecting flange 5 and the third connecting flange 6 are connected by bolts. The second connecting flange 5 is provided with a groove 14, and the third connecting flange 6 is provided with an annular protrusion 15 adapted to the groove 14. The annular protrusion 15 is movably inserted into the groove 14, and the annular protrusion 15 and the groove 14 are in transition fit. The diameter of the annular protrusion 15 is adapted to the inner diameter of the groove 14. By inserting the annular protrusion 15 into the groove 14, the sealing performance between the first exhaust pipe 1 and the second exhaust pipe 2 is further improved.
[0031] In this embodiment, a sealing ring is provided between the second connecting flange 5 and the third connecting flange 6 to further enhance the sealing performance between the second connecting flange 5 and the third connecting flange 6.
[0032] In this embodiment, the inner diameter of the exhaust manifold 8 gradually increases along the airflow direction. By gradually increasing the inner diameter of the exhaust manifold 8, the cavity inside the exhaust manifold 8 gradually increases, thereby reducing the pressure of the exhaust gas and effectively avoiding exhaust interference caused by multiple exhaust manifolds 8 exhausting at the same time, which would affect engine efficiency.
[0033] In this embodiment, the exhaust manifold 8 is provided with a rounded bend section 12. Through the reasonable bend shape, the resistance of exhaust gas in the exhaust manifold 8 can be reduced, allowing the exhaust gas to be discharged more smoothly, reducing the amount of residual exhaust gas in the cylinder, thereby improving the efficiency of the engine.
[0034] In this embodiment, a guide plate 13 is provided at the connection between the exhaust manifold 8 and the first exhaust pipe 1 or the second exhaust pipe 2. The guide plate 13 extends into the first exhaust pipe 1 or the second exhaust pipe 2 along the tangential direction of the intersection of the exhaust manifold 8 and the first exhaust pipe 1 or the second exhaust pipe 2, and guides the exhaust gas flowing into the first exhaust pipe 1 or the second exhaust pipe 2 from each exhaust manifold 8, thereby avoiding uneven exhaust pressure in each cylinder, which would affect the efficiency of the engine.
[0035] Preferably, the lengths of two adjacent exhaust manifolds 8 are different. By making the lengths of two adjacent exhaust manifolds 8 different, the exhaust gas pressures discharged from the two adjacent exhaust manifolds 8 are different, which effectively avoids exhaust interference and effectively improves the working efficiency of the engine.
[0036] In this embodiment, the fourth connecting flange 11 is provided with a diversion groove 16. The diversion groove 16 has an elongated waist-shaped structure, and the width of the diversion groove 16 is adapted to the inner diameter of the exhaust manifold 8. The width of the diversion groove 16 is equal to the inner diameter of the exhaust manifold 8. By increasing the space of the diversion groove 16, the gas flow rate of exhaust gas into the engine intake pipe is increased, so that the diversion flow rate of the exhaust gas in the diversion groove 16 can be consistent with the diversion flow rate using the EGR branch pipe. At the same time, it can reduce the excessive collision between the exhaust gas and the inner wall of the exhaust manifold 8 when the exhaust gas is diverted into the diversion groove 16, thereby reducing its intake pressure. The diversion groove 16 is connected to the engine intake port through a pipeline. The exhaust gas is discharged from the engine exhaust port. When passing through the exhaust manifold 8, due to the action of the diversion groove 16, the exhaust gas is separated at the diversion groove 16. Part of the gas enters the exhaust gas treatment system from the exhaust manifold 8, and the other part of the gas re-enters the engine intake pipe through the diversion groove 16, thereby reducing engine emissions and improving environmental protection efficiency.
[0037] In this embodiment, an arc-shaped guide plate 17 is provided on the arc-shaped sidewall of the diversion channel 16 away from the exhaust manifold 8 to reduce the collision of exhaust gas in the diversion channel 16, thereby avoiding a reduction in its intake pressure.
[0038] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several modifications and improvements can be made without departing from the structure of the present utility model. These modifications and improvements will not affect the effectiveness of the present utility model or the practicality of the patent.
Claims
1. A large gas engine exhaust pipe, characterized in that, The system includes a first exhaust pipe (1) and a second exhaust pipe (2). Both the first exhaust pipe (1) and the second exhaust pipe (2) include multiple exhaust manifolds (3) and corrugated pipes (10). Each exhaust manifold (3) and corrugated pipe (10) of the first exhaust pipe (1) and the second exhaust pipe (2) are fixed by welding. The first exhaust pipe (1) is provided with a first connecting flange (4) and a second connecting flange (5) at both ends. The second exhaust pipe (2) is provided with a third connecting flange (6) at one end and a cover plate (7) at the other end. The second connecting flange (5) and the third connecting flange (6) are connected by bolts. Each exhaust manifold (3) is provided with an exhaust manifold (8) that communicates with it. The exhaust manifold (8) is provided with a fourth connecting flange (11) at the other end. The fourth connecting flange (11) is bolted to the engine cylinder head. Each exhaust manifold (3) is provided with at least one fixing bracket (9).
2. The exhaust pipe for a large gas engine according to claim 1, characterized in that, The inner walls of the exhaust manifold (8), the first exhaust pipe (1), and the second exhaust pipe (2) are all coated.
3. The exhaust pipe for a large gas engine according to claim 1, characterized in that, The second connecting flange (5) and the third connecting flange (6) are connected by bolts. The second connecting flange (5) is provided with a groove (14), and the third connecting flange (6) is provided with an annular protrusion (15) adapted to the groove (14). The annular protrusion (15) is movably inserted into the groove (14).
4. The exhaust pipe for a large gas engine according to claim 1, characterized in that, A sealing ring is provided between the second connecting flange (5) and the third connecting flange (6).
5. The exhaust pipe of a large gas engine according to claim 1, characterized in that, The inner diameter of the exhaust manifold (8) gradually increases along the airflow direction.
6. The exhaust pipe of a large gas engine according to claim 1, characterized in that, The exhaust manifold (8) is provided with a rounded bend section (12).
7. The exhaust pipe of a large gas engine according to claim 1, characterized in that, A guide plate (13) is provided at the connection between the exhaust manifold (8) and the first exhaust pipe (1) or the second exhaust pipe (2). The guide plate (13) extends into the first exhaust pipe (1) or the second exhaust pipe (2) along the tangential direction at the intersection of the exhaust manifold (8) and the first exhaust pipe (1) or the second exhaust pipe (2).
8. The exhaust pipe of a large gas engine according to claim 1, characterized in that, The fourth connecting flange (11) is provided with a flow divider (16), which has an elongated waist-shaped structure, and the width of the flow divider (16) is adapted to the inner diameter of the exhaust manifold (8).
9. A large gas engine exhaust pipe according to claim 8, characterized in that, The flow divider (16) has an arc-shaped guide plate (17) on its arc-shaped sidewall away from the exhaust manifold (8).