KR20040015993A - Connecting pipe - Google Patents

Abstract

PURPOSE: A connecting pipe is provided to achieve improved durability of the connecting pipe by arranging a buffer structure for absorbing tensile forces produced from the contraction and expansion of the connecting pipe. CONSTITUTION: A connecting pipe comprises a rear pipe(1) connected to a exhaust manifold; a front pipe(2) connected to a turbo charger; and a bellows(3) arranged on the connector between the rear pipe and the front pipe in such a manner that the bellows absorbs tensile forces and compression forces applied from the front pipe and the rear pipe during the contraction and expansion of the connector. The rear pipe and the front pipe has ends equipped with flanges and the other ends with an insertion portion(1b) and an accommodation portion(2b) for accommodating the insertion portion. The bellows has a plurality of wave portions(3c) and is welded to the surfaces of the rear pipe and the front pipe through mounting surfaces(3a,3b) formed at both ends of the bellows.

Description

CONNECTING PIPE

The present invention relates to a connection pipe for connecting the turbocharger and the exhaust manifold provided in the vehicle intake and exhaust.

Conventional EGR (exhaust gas recirculation) pipes have bellows on the pipe to absorb expansion and contraction as the temperature of the exhaust gas changes. If these bellows are not manufactured correctly, the bellows and pipe connections may be oversized. There was a problem that a stress is generated and broken.

Accordingly, an object of the present invention is to provide a connection pipe for connecting a turbocharger and an exhaust manifold that is easy to install and has improved durability against temperature change of exhaust gas.

1 is a cross-sectional view of a connecting pipe according to the present invention,

2 is an enlarged view of a portion A of FIG. 1;

3 is a perspective view of a connection pipe according to the present invention.

<Description of the Reference Code>

1-rear pipe, 2-front pipe,

1a, 2a-flange, 3-bellows,

3c-wave shape.

In order to achieve the above object, the present invention is provided with a rear pipe connected to the exhaust manifold and a front pipe connected to the turbocharger, while the rear pipe and the front pipe are fitted in a sliding manner, The connection between the pipe and the front pipe provides a connection pipe, which has a wave shape, and is surrounded by a bellows whose both ends are welded to the rear pipe and the front pipe, respectively.

According to such a connecting pipe, as the thermal expansion, the wave portion of the bellows is contracted, the distance between the insertion portion and the receiving portion is also reduced, and as the heat shrinkage, the wave portion is expanded, and the insertion portion and The distance between the receivers is increased.

(Example)

1 is a cross-sectional view of a connecting pipe according to the present invention, which is provided with a rear pipe 1 and a front pipe 2 and a bellows 3 enclosing a connection between the rear pipe 1 and the front pipe 2. On the other hand, the rear pipe (1) is connected to the exhaust manifold, the front pipe (2) is connected to the turbocharger, the end for the connection is provided with welded flanges (1a, 2a) of approximately triangular shape respectively. . Here, the flanges 1a and 2a are formed in a triangular shape, and connecting holes 1a 'and 2a' are formed at each corner portion.

Meanwhile, in Fig. 1, the exhaust gas flows in the direction of the arrow.

2 is an enlarged view of the portion A of FIG. 1, wherein the other end of the rear pipe 1 is reduced in diameter to form an insertion part 1b, and the other end of the front pipe 2 is The receiving portion 2b into which the inserting portion 1b is fitted is formed.

In the bellows 3 having a plurality of wave-shaped portions 3c, mounting surfaces 3a and 3b formed at both ends are welded to the surfaces of the rear pipe 1 and the front pipe 2, respectively. On the other hand, the connecting pipe according to the present invention can be made of SUS material having good heat resistance.

Connection pipe according to the present invention having such a structure is repeated expansion and contraction according to the temperature state therein. That is, when the high temperature exhaust gas flows inside the connecting pipe, the connecting pipe expands, and when the inside of the connecting pipe cools, it contracts.

This repeated expansion and contraction is absorbed by the cushioning action of the connecting pipe according to the invention. That is, when the connecting pipe is expanded by high heat, the insertion portion 1b of the rear pipe 1 is extended from the receiving portion 2b of the front pipe 2 along the joint surface s in accordance with the expansion of the connecting pipe. Sliding and spaced apart to expand in the direction of the dotted line arrow from the original position (a) (the front pipe 2 also expands toward the rear pipe 1). In addition, the bellows 3 is provided with mounting surfaces 3a and 3b formed at both ends of the bellows 3 so as to be welded to the rear pipe 1 and the front pipe 2, respectively, so that the wave portion 3c is in the direction of the solid arrow. It will come and go. In other words, the width c of the wave portion 3c is reduced.

As a result, expansion of the connecting pipe due to high heat is absorbed.

On the other hand, when the connecting pipe is contracted according to the temperature drop, the insertion part 1b of the rear pipe 1 is moved from the expansion position b along the joint surface s to the front pipe 2 according to the contraction of the connecting pipe. It contracts in the direction of the solid arrow to the original position a toward the receiving portion 2b of (the front pipe 2 also contracts toward the insertion portion 1b). At this time, the wave portion 3c of the bellows 3 is opened in the dotted arrow direction. That is, the width c of the wave portion 3c is increased.

As a result, shrinkage of the connecting pipe due to the temperature drop is absorbed.

On the other hand, Figure 3 is a perspective view of the connection pipe according to the present invention.

As described above, according to the present invention, since a buffer structure capable of absorbing the tensile force and the compressive force due to repeated contraction and expansion during cold and hot of the automobile engine is formed, there is an effect of improving durability.

In addition, since flanges for mounting are formed at the ends of the front and rear pipes, there is an effect that the gasket sealing property is secured when the exhaust manifold and the turbocharger are mounted.

Claims (2)

The rear pipe 1 connected to the exhaust manifold and the front pipe 2 connected to the turbocharger, and the front pipe 2 according to the thermal expansion and contraction provided on the connection portion of the rear pipe 1 and the front pipe 2. ) And a bellows (3) absorbing the tensile and compressive forces acting from the rear pipe (1), One end of the rear pipe 1 and the front pipe 2 is provided with welding flanges 1a and 2a, and each of the other ends has an insertion part 1b having a reduced diameter, and this insertion part 1b. ) Forms a receiving portion 1b into which The bellows (3) has a plurality of wave-shaped portion (3c), characterized in that the welded to the surface of the rear pipe (1) and the front pipe (2) via the mounting surface (3a, 3b) formed at both ends, respectively Connecting pipe. 2. The connecting pipe according to claim 1, wherein the wave-shaped portion (3c) of the bellows (3) contracts according to thermal expansion, and the wave-shaped portion (3c) expands according to thermal contraction.