WO2018190450A1

WO2018190450A1 - Egr cooler having baffle for supporting gas tubes

Info

Publication number: WO2018190450A1
Application number: PCT/KR2017/004194
Authority: WO
Inventors: 조형근
Original assignee: 주식회사 코렌스
Priority date: 2017-04-14
Filing date: 2017-04-19
Publication date: 2018-10-18
Also published as: KR20180116498A; KR101977894B1

Abstract

An EGR cooler according to the present invention comprises: a body cell into and from which a cooling water flows; a plurality of gas tubes arrayed in a structure stacked in the thickness direction and mounted inside the body cell; and a baffle comprising a main bar, which is elongated in the direction of the stacking of the plurality of gas tubes and coming in close contact with one lateral side in the width direction of the plurality of gas tubes, and a plurality of extension bars which extend from the main bar in the width direction of the gas tubes and are inserted between two neighboring gas tubes. The plurality of gas tubes are positioned as far away from each other as the thickness of the extension bars. The EGR cooler according to the present invention enables the gas tubes to be maintained a fixed distance away from each other without forming a tube protrusion on the gas tubes, enables the position of a welding line of the gas tubes to be freely selected and thus enables an increase in the internal pressure strength of the gas tubes and enhancement in the corrosion resistance of the gas tubes.

Description

EZR Cooler with baffle for gas tube support

The present invention relates to an EG cooler for cooling exhaust gas flowing into an exhaust gas recirculation system (EGR: Exhaust gas hereinafter) with cooling water. It relates to an EG cooler having a baffle spaced apart.

In general, Exhaust Gas Recirculation (EGR) is a system in which a part of the exhaust gas is recycled back to the intake system to increase the concentration of CO 2 in the intake air, thereby lowering the temperature of the combustion chamber and thereby reducing the NOx.

On the other hand, the mechanism of NOx generation, in detail, consists of about 79% nitrogen, 21% oxygen and other trace elements. At room temperature, nitrogen and oxygen do not react with each other, but at high temperature (above about 1450 ° C), they react with each other to form nitrogen oxides (thermal NOx). In particular, diesel engines generate combustion by compression ignition method, and the compression ratio is getting higher due to the development of the material of the cylinder, thereby increasing the temperature of the combustion chamber. Increasing the combustion chamber temperature increases the efficiency of the thermodynamic engine, but a large amount of nitrogen oxides are generated due to the high temperature. These nitrogen oxides are the main harmful substances that destroy the global environment, causing acid rain, optical smog, respiratory disorders, and the like.

The principle of NOx reduction by EZR is to lower the maximum temperature of the combustion chamber by recirculating inert gas (steam, carbon dioxide, etc.), second, to prevent the atmosphere of nitrogen oxide formation by lean combustion, and To reduce the ignition delay and lower the local maximum temperature and pressure in the combustion chamber. On the other hand, in the diesel engine, unlike the gasoline, the NOx reduction mechanism by EGR has been reported that the reduction of the oxygen concentration is the root cause and the study that the flame temperature decrease is the cause. At this time, no conclusion about which is right is given, but the contribution of NOx reduction in oxygen concentration and flame temperature has recently been reported to be at the same level.

EZR is equipped with EZR cooler, which reduces NOx without increasing fuel economy and PM due to stricter diesel emission control, and installs a cooler (cooler) using coolant from the engine. It is a device that can be obtained.

In this case, the EZR cooler should be cooled to 700 ℃ to 200 ℃, so it must be heat-resistant and must be compactly designed to be installed inside the car. Should be minimized, and condensation is generated from exhaust gas during heat exchange and sulfuric acid is included in the condensate because it is susceptible to corrosion. Since particulate matter (PM) of the exhaust gas can block the inside of the passage, countermeasure against fouling is required.

With reference to the accompanying drawings will be described in detail with respect to the conventional EZR cooler.

1 is a vertical cross-sectional view of a conventional EG cooler, Figure 2 is a perspective view of a gas tube included in a conventional EZ cooler.

In general, an EZR cooler includes a body cell 10 through which coolant flows in and out, and a plurality of gas tubes 20 installed in the body cell 10 through which exhaust gas flows. A plurality of tube protrusions 22 are formed in the gas tube 20, and two neighboring gas tubes 20 are disposed such that the ends of the respective tube protrusions 22 abut each other. Cooling water may flow between the tubes 20.

At this time, the gas tube 20 is produced by welding one end by rolling one metal plate, because a plurality of tube projections must be formed on a wide surface (top and bottom surfaces of FIG. 2) of the gas tube 20. The line is located on the narrow side of the gas tube 20 (left side or right side in FIG. 2). The high temperature and high pressure exhaust gas flows inside the gas tube 20, and the pressure of the exhaust gas is mainly applied to the wide surface of the gas tube 20, so that the welding line has a narrow surface of the gas tube 20 as described above. If formed in the can cause problems such as the welding line is opened.

1 and 2, when a plurality of tube protrusions 22 are formed in the gas tube 20, that is, when the gas tube 20 is formed in a shape having a curvature rather than a smooth plane, gas The exhaust gas passing through the inside of the tube 20 is concentrated on the bent portion around the tube protrusion 22, so that the corresponding portion is easily corroded, which causes a problem that the durability of the gas tube 20 decreases.

The present invention has been proposed to solve the above problems, it is possible to maintain a constant distance between the gas tubes even if the tube projection is not formed in the gas tube, it is possible to freely select the welding line position of the gas tube The purpose of the present invention is to increase the pressure resistance of the gas tube and to provide an EG cooler that can improve the corrosion resistance of the gas tube.

Easy R cooler according to the present invention for achieving the above object, the body cell to which the coolant flows out; A plurality of gas tubes arranged in the thickness direction and mounted in the body cell; A plurality of main bars extending in the stacking direction of the plurality of gas tubes and closely contacted to one side of the plurality of gas tubes in a width direction, and inserted between two neighboring gas tubes extending from the main bar in the width direction of the gas tube; And a baffle configured as an extension bar, wherein the plurality of gas tubes are spaced apart from each other by the thickness of the extension bar.

The gas tube is formed in a rectangular tube shape having a width wider than a thickness by bending one metal plate and then welding both ends, and a welding line is formed at an upper wall center or a lower wall center.

The outermost extension bar of the plurality of extension bars is inserted between the outermost gas tube and the inner surface of the body cell, the outermost gas tube and the inner surface of the body cell is the extension Spaced apart by the thickness of the bar.

The plurality of extension bars are formed to have the same thickness, and the separation distance between two neighboring gas tubes and the outermost gas tube and the body cell are equally set.

The baffle is coupled to the longitudinal stop of the gas tube.

The baffles are provided in pairs so as to be coupled to both sides in the width direction of the gas tube.

The pair of baffles are coupled to the longitudinal interruption of the gas tube so that the extension bar ends face each other, and the two extension bar ends facing each other are spaced apart so that the coolant flows.

One side wall of the body cell is coupled to the cooling water inlet tube and the cooling water outlet tube, the main bar is in close contact between the point where the cooling water inlet tube is coupled and the cooling water outlet tube of the one side wall of the body cell. .

The EZR cooler according to the present invention can maintain the separation distance between the gas tubes even without forming a tube protrusion in the gas tube, and can freely select the position of the welding line of the gas tube to increase the pressure resistance of the gas tube. It can be increased, and the corrosion resistance of the gas tube can be improved.

1 is a vertical cross-sectional view of a conventional RG cooler.

2 is a perspective view of a gas tube included in a conventional EZC cooler.

3 is a perspective view of an EG cooler according to the present invention.

4 is a cross-sectional perspective view of an EZ cooler according to the present invention.

5 and 6 are a perspective view and an exploded perspective view showing a coupling structure of the support baffle included in the EG cooler according to the present invention.

7 is a cross-sectional view showing a cooling water flow path of an EG cooler according to the present invention.

8 and 9 are a perspective view and an exploded perspective view showing a coupling structure of the support baffle included in the second embodiment of an EG cooler according to the present invention.

Fig. 10 is a cross-sectional view showing the cooling water flow path of the EZC cooler according to the second embodiment of the present invention.

Hereinafter, an embodiment of an EG cooler according to the present invention will be described in detail with reference to the accompanying drawings.

Figure 3 is a perspective view of an EG cooler according to the present invention, Figure 4 is a cross-sectional perspective view of the EG cooler according to the present invention, Figure 5 and Figure 6 is a coupling structure of the support baffle included in the EG cooler according to the present invention Is a perspective view and an exploded perspective view.

EZ cooler according to the present invention is a device for heat exchange between the exhaust gas and the cooling water, the cooling water inlet pipe 110 and the cooling water outlet pipe 120 is provided with a body cell 100 and the cooling water flows in and out, thickness direction A plurality of gas tubes 200 are arranged in a stacked structure to be mounted in the body cell 100, and wave fins 300 mounted in the gas tube 200 are provided as basic components. Even if a separate tube protrusion is not formed in the 200, that is, even though the surface of the gas tube 200 is formed in a smooth flat shape, two neighboring gas tubes 200 are configured to be spaced apart at regular intervals. There is a big feature.

That is, the EZR cooler according to the present invention has the biggest feature in that it further includes a baffle 400 which spaces the plurality of gas tubes 200 at regular intervals. The baffle 400 extends long in the stacking direction of the plurality of gas tubes 200 (up and down in this embodiment) to be in close contact with one side of the plurality of gas tubes 200 in the width direction (right side in FIG. 5). The bar 410 and a plurality of extension bars 420 extending from the main bar 410 in the width direction of the gas tube 200 and inserted between two neighboring gas tubes 200.

The extension bar 420 inserted between two neighboring gas tubes 200 is in contact with the bottom surface of the gas tube 200 located above and the top surface of the gas tube 200 located below the bar. The gas tube 200 and the gas tube 200 positioned below the gas tube 200 are kept spaced apart by the thickness of the extension bar 420.

As mentioned above, when the plurality of gas tubes 200 are configured to be spaced apart by the baffle 400, there is no need to form tube protrusions on the gas tubes 200, that is, the wall surface of the gas tubes 200 is planar. Since the exhaust gas flowing inside the gas tube 200 is concentrated on the curved portion around the tube protrusion, the corresponding portion may be easily corroded. In addition, if the bending is formed in the gas tube 200, noise and vibration is generated during the flow of the exhaust gas, the gas tube 200 included in the present invention is a noise generated during the flow of the exhaust gas because the inner surface forms a smooth plane There is an advantage that the vibration is significantly reduced.

Meanwhile, the gas tube 200 applied to the EZC cooler is formed in a rectangular tube shape having a width wider than the thickness thereof, and is mounted in a stacked structure in the thickness direction. The gas tube 200 is manufactured by welding both ends after bending one metal plate. do. At this time, since the tube projection need not be provided on the surface of the gas tube 200 included in the present invention, the welding line may be located at any point. That is, the welding line may be formed on the widthwise sidewall of the gas tube 200 (in the present embodiment, the left side wall or the right side wall), and the thickness sidewall of the gas tube 200 (the upper side wall in this embodiment). It may be formed on the lower side wall).

Since the side wall of the gas tube 200 is made wider in the thickness direction than the width side wall, the pressure of the exhaust gas flowing into the gas tube 200 is mainly applied in the vertical direction. Therefore, when the welding line of the gas tube 200 is formed on the side wall in the width direction of the gas tube 200, there is an increased risk of the welding line being opened by the pressure of the exhaust gas. Is preferably formed in the center of the upper side wall or the lower side wall.

When the welding line of the gas tube 200 is formed in the center of the upper wall or the lower wall of the gas tube 200 as described above, even if the pressure of the exhaust gas is large, the welding line does not easily open, and accordingly, the gas tube 200 The effect of increasing the structural strength of can be obtained. In addition, the gas tube 200 generally has a widthwise sidewall (left or right wall) narrower than the thickness sidewall (upper or lower wall) as mentioned above, and thus, the conventional gas tube 200 (20). There may be many difficulties in welding in the widthwise side wall. On the other hand, when welding from the side wall in the thickness direction, such as the gas tube 200 included in the present invention, it is possible to obtain an advantage that the welding operation becomes very easy.

Since the exhaust gas flowing inside the gas tube 200 exchanges heat with the cooling water flowing outside the gas tube 200, the heat exchange rate of each gas tube 200 increases and decreases in proportion to the amount of cooling water flowing outside. EZ cooler according to the present invention, the heat exchange rate of each gas tube 200 to be the same, that is, the flow rate of the coolant contacting the gas tube 200 located in the middle and the gas tube 200 is located on the outermost In order to maintain the same flow rate of the cooling water, the distance between the adjacent two gas tubes 200 and the outermost gas tube 200 and the body cell 100 are preferably set equally. Do.

Therefore, the extension bar 420 located at the outermost side of the plurality of extension bars 420 is inserted between the gas tube 200 located at the outermost side and the inner surface of the body cell 100, and the gas tube 200 It is preferable that the outer surface and the inner surface of the body cell 100 is set to contact. As described above, when the outermost extension bar 420 is in contact with both the gas tube 200 and the body cell 100, the inner surface of the gas tube 200 and the body cell 100 positioned at the outermost side may be Bars are spaced apart by the thickness of the extension bar 420, all the gas tubes 200 can be obtained the effect that the heat exchange rate is the same.

Of course, as mentioned above, in order for the separation distance between two neighboring gas tubes 200 to be equally set and the separation distance between the outermost gas tube 200 and the body cell 100, The plurality of extension bars 420 should be manufactured to have the same thickness.

When the baffle 400 for maintaining a constant distance between the gas tubes 200 is coupled to one side in the longitudinal direction of the gas tube 200, the other side in the longitudinal direction of the gas tube 200 may not be stably fixed and shaken. There is concern. Therefore, the baffle 400 is preferably coupled to the longitudinal interruption of the gas tube 200 so that both sides of the gas tube 200 can be stably balanced and fixed in the longitudinal direction.

At this time, the coolant inlet pipe 110 for supplying the coolant into the body cell 100 and the coolant outlet pipe 120 for discharging the coolant in the body cell to the outside are provided on one side wall of the body cell 100. The main bar 410 may be in close contact between a point where the coolant inlet pipe 110 is coupled and a point where the coolant outlet pipe 120 is coupled to one sidewall of the body cell 100.

As such, when the baffle 400 is mounted between the coolant inlet pipe 110 and the coolant outlet pipe 120, the coolant introduced into the body cell 100 through the coolant inlet pipe 110 is illustrated in FIG. 7. As shown in FIG. 7, the baffle 400 flows to a portion (lower region in FIG. 7) and is then U-turned to be discharged through the coolant outlet pipe 120. The coolant introduced into the body cell 100 is The gas tube 200 is in uniform contact with the entire outer surface. Therefore, it is possible to obtain the effect of maximizing the cooling performance of the EG cooler according to the present invention.

In this case, if the baffle 400 is not completely in contact with the inner wall of the body cell 100, since the coolant introduced through the coolant inlet may flow directly through the baffle 400 to the coolant outlet, the baffle 400 may be Both sides corresponding to the inner wall of the body cell 100 should be in close contact with the inner wall of the body cell 100.

8 and 9 are a perspective view and an exploded perspective view showing a coupling structure of the support baffle 400 included in the second embodiment of the easy cooler according to the present invention, Figure 10 is a second embodiment of the easy cooler according to the present invention It is sectional drawing which shows the cooling water flow path of an example.

5 to 7 when one baffle 400 is configured to maintain the separation distance between the gas tubes 200, that is, the baffle 400 is coupled to only one side in the width direction of the gas tube 200 In this case, the other side in the width direction of the gas tube 200 may not be stably fixed and may shake.

Accordingly, the baffles 400 may be provided in pairs and may be coupled to both sides of the gas tube 200 in the width direction. As described above, when a pair of baffles 400 are respectively coupled to both sides of the gas tube 200 in the width direction, the plurality of gas tubes 200 have an advantage that the spacing between the one side and the other side in the width direction can be stably fixed. have.

At this time, when the ends of the pair of baffles 400 abut each other, that is, when the ends of the extension bar 420 included in each baffle 400 abut each other, the inner space of the body cell 100 is a pair It is isolated by the baffle 400 of the bar, there is a problem that the cooling water introduced through the coolant inlet pipe 110 does not flow to the coolant outlet pipe 120. Therefore, the pair of baffles 400 are coupled to the longitudinal interruption of the gas tube 200 so that the ends of the extension bars 420 face each other, and the ends of the two extension bars 420 facing each other are coolant. It is desirable to be spaced a certain distance to flow.

As such, when the coolant may flow between two extension bars 420 facing each other, as shown in FIG. 10, the coolant introduced through the coolant inlet pipe 110 may be coupled to the opposite side of the coolant inlet pipe 110. In the exemplary embodiment, the fluid flows to the bottom end and passes between two extension bars 420 after U-turn. Some of the coolant passing between the two extension bars 420 is immediately discharged to the outside through the cooling water outlet, the rest of the coolant passing between the two extension bars 420 flows to the lower side and then again U-turn (U- Bar is discharged through the coolant outlet pipe 120, the coolant introduced into the body cell 100 may be evenly contacted over the entire outer surface of the gas tube (200).

On the other hand, even when the baffles 400 are provided in pairs as shown in this embodiment, all sides of the baffle 400 corresponding to the inner wall of the body cell 100 closely adhere to the inner wall of the body cell 100. Should be.

As mentioned above, although this invention was demonstrated in detail using the preferable Example, the scope of the present invention is not limited to a specific Example and should be interpreted by the attached Claim. In addition, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

Claims

A body cell into which coolant flows out;

A plurality of gas tubes arranged in the thickness direction and mounted in the body cell;

A plurality of main bars extending in the stacking direction of the plurality of gas tubes and closely contacted to one side of the plurality of gas tubes in a width direction, and inserted between two neighboring gas tubes extending from the main bar in the width direction of the gas tube; A baffle composed of an extension bar;

Including,

And the plurality of gas tubes are spaced apart from each other by the thickness of the extension bar.
The method according to claim 1,

The gas tube,

EZ cooler, characterized in that the bent one of the metal plate is formed in a square tube shape wider than the thickness through the process of welding both ends, the welding line is formed in the upper wall center or the lower wall center.
The method according to claim 1,

The outermost extension bar of the plurality of extension bars is inserted between the outermost gas tube and the inner surface of the body cell,

The outermost gas tube and the inner surface of the body cell is an easy cooler, characterized in that spaced apart by the thickness of the extension bar.
The method according to claim 3,

The plurality of extension bars are formed to the same thickness,

The separation distance between two neighboring gas tubes and the outermost gas tube and the body cell is characterized in that the same distance cooler.
The method according to claim 1,

And the baffle is coupled to a longitudinal stop of the gas tube.
The method according to claim 1,

The baffle is an EG cooler, characterized in that provided in pairs so as to be respectively coupled to both sides in the width direction of the gas tube.
The method according to claim 6,

The pair of baffles are coupled to the longitudinal interruption of the gas tube and arranged so that the ends of the extension bars face each other,

The ends of the two extension bars facing each other are separated so that the coolant flows.
The method according to claim 1,

Cooling water inlet pipe and the cooling water outlet pipe is coupled to one side wall of the body cell,

The main bar is an EG cooler, characterized in that the close contact between the point of the cooling water inlet pipe is coupled to the point of the cooling water inlet pipe of the side wall of the body cell.