CN108000074A - A kind of low noise low vibration exhaust-gas muffler shell manufacture craft - Google Patents

Abstract

A low-noise and low-vibration exhaust muffler shell manufacturing process, the specific steps are as follows: 1) Reel: select a suitable size of sheet material according to the size of the exhaust muffler shell required, and roll the sheet material into a cylindrical structure ;2) Spot welding: Spot welding is performed at the joints of the cylindrical structure, and the welding spots are evenly distributed along the axis of the cylindrical structure; 3) Flanging: Flanging the two ends of the cylindrical structure; Welding: Add several reinforced spot welds at symmetrical positions on both sides of the seam. The manufacturing process is simple in operation and high in manufacturing efficiency, and can obviously reduce the vibration and noise of the exhaust muffler casing in use.

Description

Manufacturing process of low-noise and low-vibration exhaust muffler shell

technical field

The patent of the invention relates to the manufacturing process of the muffler shell, in particular to a low-noise and low-vibration exhaust muffler shell manufacturing process and its debugging method.

Background technique

With the rapid development of my country's automobile industry, the NVH characteristics of automobiles have become an important indicator to measure the quality of vehicles. The noise inside the car is an important factor that affects the comfort of the occupants, the degree of hearing impairment, the intelligibility of speech, and the ability to recognize various audio signals outside the car. The quality of the sound inside the car has become one of the important factors for people to evaluate and purchase cars.

The exhaust muffler housing made in the prior art is prone to generate relatively serious noise and vibration due to insufficient structural strength and poor structural rigidity, and also due to resonance and other reasons during the practical process of driving, which will cause discomfort to the occupants of the vehicle.

Contents of the invention

The patent of the present invention is completed in order to solve the deficiencies in the prior art. The purpose of the patent of the present invention is to provide a low-noise and low-vibration exhaust muffler shell manufacturing process. Reduce the vibration and noise of the exhaust muffler shell in use.

The technical solution of the present invention is: a low-noise and low-vibration exhaust muffler shell manufacturing process, the specific steps are as follows:

1) Reel: Select a suitable size sheet according to the size of the exhaust muffler shell required, and roll the sheet into a cylindrical structure;

2) Spot welding: Spot welding is carried out at the joints of the cylindrical structure, and the welding points of the joints are evenly distributed along the axis of the cylindrical structure;

3) Flange: flanging the two ends of the tubular structure;

4) Strengthening spot welding of the shell: Add several strengthening spot welding at symmetrical positions on both sides of the seam.

In the above scheme, after the exhaust muffler shell is made into shape, several reinforced spot welds are added on both sides of the seam on the shell to improve the rigidity of the cylinder structure, and the natural frequency of the cylinder can be changed by strengthening the spot welds , is to effectively suppress the noise and vibration of the rolled automobile muffler barrel assembly.

Further, in step 1), double-layer sheets are rolled into a cylindrical structure. Compared with the single-layer sheet material, the structural strength and rigidity of the double-layer sheet material are significantly improved, which can significantly reduce the vibration and noise of the exhaust muffler shell.

Further, in step 2), the number of spot welding is 10-14. Reasonably setting the number of spot welds can not only ensure that the structural strength meets the requirements, but also prevent excessive spot welds from causing welding deformation, and at the same time reduce processing difficulty and cost.

Further, after completing step 3), before starting step 4), it is also necessary to punch a central hole in the middle of the cylindrical structure.

Further, a reinforcing plate is arranged on the middle hole, and the reinforcing plate is fixedly connected with the cylindrical structure through spot welding. After the reinforcing plate is arranged, the structural strength of the tubular structure is prevented from being reduced after the central hole is punched.

Further, the welding spots on the reinforcing plate are arranged symmetrically with respect to the circular center of the middle hole. The symmetrically arranged solder joints can reduce the number of solder joints under the premise of ensuring sufficient welding strength.

Further, the reinforced solder joints on both sides of the seam form an isosceles triangle. The isosceles triangle solder joints form a circular link, which has a good resistance to the impact of the airflow, enhances the rigidity of the muffler, and can reduce the noise generated by the vibration caused by the impact of the airflow.

Further, during spot welding, spot welding is located at the apex of the isosceles triangle to strengthen the apex of the welding point, and then points to another part of the isosceles triangle.

Further, the number of reinforced welding spots on one side of the seam is 3 to 6.

By testing the comfort of the ear, it is judged that 1 symmetrical solder joint is added in the middle of the joint of the cylindrical structure, and the abnormal noise of the shell due to airflow vibration is relatively large. The abnormal noise caused by vibration is slightly smaller. Add 3 symmetrical solder joints in the middle of the shell seam, and the abnormal noise of the shell due to airflow vibration will disappear. Combined with cost considerations, it is confirmed that the shell adds 3 symmetrical solder joints. The solder joint position is In the middle of the seam of the shell, there are 3 points symmetrically arranged in an isosceles triangle shape for the best effect.

Further, the distance between the reinforcing welding spot and the seam is 2cm~5cm.

Further, the distance between the reinforcing welding spots is 4cm~12cm.

Beneficial effects of the present invention: the exhaust muffler shell that can be produced by the present invention has the advantages of simple and reasonable structure, and the rigidity of the wall of the cylinder material can be obviously provided by setting the strengthening solder joints, effectively restraining the Noise and vibration of the muffler barrel assembly.

Description of drawings

Fig. 1 - the reel of the low-noise and low-vibration exhaust muffler shell manufacturing process of the present invention and the processing schematic diagram of spot welding;

Fig. 2—the reinforced spot welding schematic diagram of the manufacturing process of the low-noise and low-vibration exhaust muffler shell of the present invention;

Fig. 3 —Schematic diagram of processing spot welding of reinforcing plates of the low-noise and low-vibration exhaust muffler shell manufacturing process of the present invention.

Explanation of reference signs: 1—tubular structure, 2—joint joint, 3—strengthening plate, 4—welding spot of reinforcing plate, 5—strengthening welding spot, 6—processed part, 7—welding spot of patchwork seam.

Detailed ways

As shown in Figures 1 to 3: a low-noise and low-vibration exhaust muffler shell manufacturing process, the specific steps are as follows:

1) Reel: Select a suitable size sheet according to the size of the exhaust muffler shell required, and roll the sheet into a cylindrical structure 1;

2) Spot welding: Spot welding is carried out at the joint 2 of the cylindrical structure 1, and the welding spots 7 of the joint are evenly distributed along the axis of the cylindrical structure 1;

3) Flanging: forming the two ends of the tubular structure 1 by flanging;

4) Strengthening spot welding of the shell: at the symmetrical positions on both sides of the seam 2, several strengthening spot weldings are added.

In the above scheme, after the exhaust muffler shell is made into shape, several reinforced spot welds are added on both sides of the seam 2 on the shell to improve the rigidity of the cylinder structure, and the inherent cylindrical shape can be changed by strengthening the spot welds. The frequency is to effectively suppress the noise and vibration of the rolled automobile muffler barrel assembly.

In step 1), a cylindrical structure 1 is formed by rolling double-layer sheets. Compared with the single-layer sheet material, the structural strength and rigidity of the double-layer sheet material are significantly improved, which can significantly reduce the vibration and noise of the exhaust muffler shell.

In step 2), the number of spot welding is 10~14. Reasonably setting the number of spot welds can not only ensure that the structural strength meets the requirements, but also prevent excessive spot welds from causing welding deformation, and at the same time reduce processing difficulty and cost.

After completing step 3), before starting step 4), it is also necessary to punch a central hole in the middle of the cylindrical structure 1 .

A reinforcing plate 3 is arranged on the middle hole, and the reinforcing plate 3 is fixedly connected with the cylindrical structure 1 by spot welding. After the reinforcing plate 3 is installed, the structural strength of the cylindrical structure 1 can be prevented from being reduced after the central hole is punched, thereby significantly improving the structural stability of the shell when the airflow rushes into the muffler shell, thereby achieving the effect of vibration reduction and noise reduction.

The reinforcement plate welding spots 4 on the reinforcement plate 3 are arranged symmetrically with respect to the circular center of the middle hole. The symmetrically arranged solder joints can reduce the number of solder joints under the premise of ensuring sufficient welding strength.

The number of reinforced spot welds 5 on both sides of the patchwork 2 is three, and form an isosceles triangle structure, the base of the isosceles triangle is parallel to the patchwork 2, and the angle of the bottom angle is 30°.

For this muffler, it is the characteristic of the air intake in the middle part, the airflow hits the middle part and spreads to both sides, and the impact force is the largest in the middle part. Therefore, one point of symmetrical spot welding in the middle seam is the apex of the isosceles triangle. In order to strengthen the spot welding strength, one point is spot welded on both sides of the apex, and because the air flow spreads evenly to both sides, the welding points on both sides are symmetrical The distribution is that the solder joints form an isosceles triangle, the bottom edge is parallel to the joint 2, and the angle of the bottom angle is 30°, which can enhance the strength of the solder joints, increase the rigidity of the muffler, and reduce the noise caused by the vibration caused by the airflow impact.

Specifically, put the cylindrical structure 1 into the special-shaped electrode head of the vertical spot welding machine, first spot-weld the reinforced spot weld 5 at the apex of the isosceles triangle, and then spot-weld the other two points of the isosceles triangle. In the above spot welding, it is not possible to point through the leakage gas to affect the performance of the muffler; in addition, because the muffler takes in air from the middle opening of the shell, and because the air flow impacts the joint of the shell, the impact force of the middle part is greater than that of the two ends, so the middle joint 2 is compared with the two The end seam is cracked first, so adding solder joints in the middle can enhance the rigidity of the cylinder.

The distance between the reinforced spot welds 5 and the patchwork 2 is 2cm~5cm, and the distance between the reinforced spot welds 5 is 4cm~12cm. When the sizes of the muffler shells are different, the effect of noise reduction and vibration reduction can be ensured by adjusting the distance between the reinforcing spot welds 5 .

The above only describes several specific embodiments in the patent of the present invention, but it cannot be regarded as the protection scope of the patent of the present invention. Any equivalent change or modification or proportional enlargement or reduction made according to the design spirit in the patent of the present invention, etc. , should be considered to fall into the protection scope of the patent of the present invention.

Claims (10)

1. A low-noise and low-vibration exhaust muffler housing manufacturing process, characterized in that: the specific steps are as follows: 1) Reel: Select a suitable size sheet according to the size of the exhaust muffler shell required, and roll the sheet into a cylindrical structure; 2) Spot welding: Spot welding is carried out at the joints of the cylindrical structure, and the welding points of the joints are evenly distributed along the axis of the cylindrical structure; 3) Flange: flanging the two ends of the tubular structure; 4) Strengthening spot welding of the shell: Add several strengthening spot welding at symmetrical positions on both sides of the seam. 2. The manufacturing process of a low-noise and low-vibration exhaust muffler shell according to claim 1, characterized in that: in step 1), double-layer sheets are used to roll into a cylindrical structure. 3. The low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 1 or 2, characterized in that: in step 2), the number of spot welding is 10-14. 4. A low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 1 or 2, characterized in that: after step 3) is completed, before step 4) is started, it is necessary to carry out the process in the middle of the cylindrical structure Punch the middle hole. 5. A low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 4, characterized in that: a reinforcement plate is provided on the middle hole, and the reinforcement plate is fixedly connected to the cylindrical structure by spot welding. 6. The manufacturing process of a low-noise and low-vibration exhaust muffler shell according to claim 4, wherein the welding spots on the reinforcing plate are arranged symmetrically with respect to the circular center of the middle hole. 7. A low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 1 or 2, characterized in that: the reinforced solder joints on both sides of the seam form an isosceles triangle. 8. A low-noise, low-vibration exhaust muffler shell manufacturing process according to claim 7, characterized in that: during spot welding, first spot weld the apex at the apex of the isosceles triangle to the point where the reinforced solder joint is located, and then point the isosceles Point to the other part of the triangle. 9. The low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 7, characterized in that: the number of reinforcing solder joints on one side of the seam is 3 to 6. 10. A low-noise and low-vibration exhaust muffler shell manufacturing process according to claim 7, characterized in that: the distance between the reinforced solder joints and the seam is 2 cm ~ 5 cm, and the distance between the reinforced solder joints The spacing is 4cm~12cm.