CN211258833U

CN211258833U - EGR pipeline for preventing waste gas condensate water from flowing backwards

Info

Publication number: CN211258833U
Application number: CN201922001062.5U
Authority: CN
Inventors: 李培营; 杜喜云; 时杰
Original assignee: FAW Jiefang Automotive Co Ltd
Current assignee: FAW Jiefang Automotive Co Ltd
Priority date: 2019-11-19
Filing date: 2019-11-19
Publication date: 2020-08-14
Anticipated expiration: 2029-11-19

Abstract

The utility model discloses an EGR pipeline for preventing exhaust condensate from flowing backwards, which belongs to the technical field of an engine exhaust gas recirculation system and comprises a connecting flange, an EGR pipeline outer wall and an EGR pipeline interlayer; the one end of EGR pipeline outer wall is provided with flange, flange's the other end and EGR cooler are connected, and EGR pipeline intermediate layer is equipped with in EGR pipeline inner wall below pressure, can be used to when the temperature is lower, and vapor meets cold pipe wall liquefaction in the waste gas, prevents the liquefied water backward flow, and the comdenstion water no longer flows into booster or EGR valve, but the storage is in EGR pipeline intermediate layer. The EGR pipeline interlayer with the grate holes is pressed on the pipeline, so that the installation is simple; a water storage space is formed between the interlayer and the pipe wall, the service life of key parts on two sides of the pipeline can be prolonged, and the bottom of the inner wall of the pipeline is also provided with an electric control drain valve which can discharge excessive condensed water in time.

Description

EGR pipeline for preventing waste gas condensate water from flowing backwards

Technical Field

The utility model belongs to the technical field of engine exhaust gas recirculation system, concretely relates to prevent EGR pipeline of exhaust gas condensate water refluence.

Background

With the coming of the national six-emission regulations, the requirements of engine emissions are becoming stricter. For natural gas engines, the mainstream technical route to reach the national six emission standards is EGR + equivalent combustion + TWC (three way catalysis).

The EGR technology leads a part of waste gas of the engine to participate in combustion, so that nitrogen oxide after combustion can be effectively reduced. Equivalent combustion means that the theoretical mass of air required for complete combustion of a unit mass of fuel is equal to the mass of air actually supplied, and since the main component of natural gas is CH4 (methane), the content of H20 in the exhaust gas after complete combustion exceeds 12%.

The EGR system mainly comprises an EGR cooler, an EGR valve and an EGR pipeline. The EGR cooler is limited to a large volume, and is mostly located on the upper side of the engine. When the ambient temperature is too low, the engine stops or idles, water vapor in exhaust gas in the EGR pipeline is condensed, and condensed water flows back to a low-level supercharger, an EGR valve and a mixer, so that key parts are oxidized or frozen in winter, the engine cannot be started, and the service life of the key parts is reduced.

In summary, how to solve the problem of backflow of the condensed water in the EGR pipeline becomes a problem to be solved urgently by those skilled in the art.

SUMMERY OF THE UTILITY MODEL

Because water content is more in the waste gas in order to solve existence among the prior art, when ambient temperature crosses lowly, the engine stops or the idle speed, the vapor condensation in the waste gas in the EGR pipeline, the comdenstion water flows back booster of low level, EGR valve and blender, causes key spare part oxidation corrosion, leads to the reduction of engine key spare part life-span or the unable scheduling problem that starts in winter, the utility model provides a prevent EGR pipeline of waste gas comdenstion water refluence, use on the engine of assembly EGR system, be particularly useful for the more natural gas engine of water content in the waste gas, can effectively prevent the freezing jamming of EGR valve, corrosion booster, promote the engine reliability.

The utility model discloses a following technical scheme realizes:

an EGR pipeline for preventing exhaust gas condensate water from flowing back comprises a connecting flange 111, an EGR pipeline outer wall 112 and an EGR pipeline interlayer 113; one end of EGR pipeline outer wall 112 is provided with flange 111, flange 111's the other end and EGR cooler 12 are connected, and EGR pipeline intermediate layer 113 is equipped with in EGR pipeline inner wall below pressure, can be used to when the temperature is lower, and vapor meets cold pipe wall liquefaction in the waste gas, prevents the liquefied water backward flow, and the comdenstion water no longer flows into booster or EGR valve, but the storage is in EGR pipeline intermediate layer 113.

Further, the EGR pipe interlayer 113 includes an interlayer main body 1132, one end of the interlayer main body 1132 is press-fitted below the inner wall of the EGR pipe by a press-fitting flange 1131, the interlayer main body 1132 is further provided with a plurality of rows of water drainage grate holes 1133, and the water drainage grate holes 1133 are arranged in a staggered manner for most of condensed water to flow into the EGR pipe interlayer 113.

Further, an electrically controlled drain valve 114 is disposed below the inner wall of the EGR pipeline for draining excessive condensed water.

Compared with the prior art, the utility model has the advantages as follows:

the EGR pipeline interlayer with the comb holes is pressed at the bottom of the inner wall of the EGR pipeline, so that the installation is simple; a water storage space is formed between the interlayer and the pipe wall, the service life of key parts on two sides of the pipeline can be prolonged, and the bottom of the inner wall of the pipeline is also provided with an electric control drain valve 114 which can discharge excessive condensed water in time.

Drawings

FIG. 1 is a schematic diagram of a natural gas engine exhaust gas recirculation system;

fig. 2 is a schematic structural view of an EGR pipeline for preventing backflow of condensed water in exhaust gas according to the present invention;

FIG. 3 is an enlarged view of a portion of FIG. 2;

FIG. 4 is a schematic diagram of an EGR conduit sandwich;

in the figure: the device comprises a supercharger 1, an air filter 2, a piston 3, an exhaust valve 4, an ignition plug 5, an intake valve 6, a cylinder cover 7, a cylinder sleeve 8, a mixer 9, an EGR valve 10, an EGR outlet pipe 11, an EGR cooler 12, an EGR inlet pipe 13, a connecting flange 111, an EGR pipeline outer wall 112, an EGR pipeline interlayer 113, an electric control water drain valve 114, a press fitting flange 1131, an interlayer main body 1132 and a water drain grate hole 1133.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings. It is to be understood that the description of the embodiments herein is for purposes of illustration and explanation only and is not intended to limit the invention.

Example 1

As shown in fig. 1, a natural gas engine exhaust gas recirculation system has a piston 3 reciprocating in a cylinder 8 of an engine, and a combustion chamber is formed between an upper surface of the piston 3 and a lower surface area of a cylinder head 7, an inner surface of the cylinder 8, a lower surface of an intake valve 6, and a lower surface of an exhaust valve 4. Air enters a mixer 9 through a filter 2 and a supercharger 1; a part of waste gas enters an EGR cooler 12 through an EGR inlet pipe 13, and enters a mixer 9 through an EGR outlet pipe 11 and an EGR valve 10 after being cooled; finally, the gas, the air and the waste gas are mixed evenly and then enter the cylinder, and are ignited by the spark plug 5 to do work. The combustion mode shown in fig. 1 can reduce NOx emissions by introducing exhaust gas for re-combustion through the EGR system, but because the EGR cooler 12 is bulky, the EGR cooler 12 is mostly located on the upper side of the engine. When the ambient temperature is too low, the engine stops or idles, water vapor in exhaust gas in the EGR pipeline is condensed, and condensed water flows back to the low-level supercharger 1, the EGR valve 10 and the mixer 9, so that key parts are oxidized or frozen in winter, the engine cannot be started, and the service life of the key parts is reduced.

As shown in fig. 2, the EGR pipeline for preventing backflow of condensed water in exhaust gas of the present invention includes a connecting flange 111, an EGR pipeline outer wall 112 and an EGR pipeline interlayer 113; one end of the outer wall 112 of the EGR pipeline is provided with a connecting flange 111, the other end of the connecting flange 111 is connected with the EGR cooler 12, and an EGR pipeline interlayer 113 is pressed below the inner wall of the EGR pipeline and can be used for preventing liquefied water from flowing back when water vapor in exhaust gas meets the cold pipe wall and condensed water does not flow into a supercharger or an EGR valve any more but is stored in the EGR pipeline interlayer 113 when the temperature is lower; an electrically controlled drain valve 114 is further disposed below the inner wall of the EGR pipeline for draining excessive condensed water.

EGR pipeline intermediate layer 113 includes intermediate layer main part 1132, and intermediate layer main part 1132 material is the ordinary steel body, intermediate layer main part 1132's one end is pressed fitting in EGR pipeline inner wall below by pressure equipment flange 1131, still be provided with the multirow on the intermediate layer main part 1132 and turn on the water the comb hole 1133, every water drainage comb hole 1133 straggles to arrange for the most comdenstion water of intermediate layer pipe wall flows into EGR pipeline intermediate layer 113.

The utility model discloses a prevent EGR pipeline of condensate water refluence in waste gas's theory of operation as follows:

when the temperature is lower, the water vapor in the waste gas is liquefied when meeting the cold pipe wall, in order to prevent the liquefied water from flowing back, an EGR pipeline interlayer 113 is pressed below the inner wall of the pipeline, and condensed water does not flow into a supercharger or an EGR valve any more due to the existence of the interlayer and is stored in the interlayer. In order to prevent water vapor condensation on the pipe wall of the interlayer, a plurality of rows of grid holes are designed on the interlayer, each row of grid holes are arranged in a staggered manner, and most of the condensed water on the pipe wall flows into the interlayer through the grid holes. In order to prevent the extreme condition of idling or continuous start-stop, an electric control water drain valve is additionally arranged at the lowest position of the inner wall of the pipeline, so that the condition of excessive condensate water is prevented.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the details of the above embodiments, and the technical concept of the present invention can be within the scope of the present invention to perform various simple modifications to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and in order to avoid unnecessary repetition, the present invention does not need to describe any combination of the features.

In addition, various embodiments of the present invention can be combined arbitrarily, and the disclosed content should be regarded as the present invention as long as it does not violate the idea of the present invention.

Claims

1. An EGR pipeline for preventing exhaust gas condensate water from flowing back is characterized by comprising a connecting flange (111), an EGR pipeline outer wall (112) and an EGR pipeline interlayer (113); one end of the EGR pipeline outer wall (112) is provided with a connecting flange (111), the other end of the connecting flange (111) is connected with the EGR cooler (12), and an EGR pipeline interlayer (113) is arranged below the EGR pipeline inner wall in a pressing mode.

2. The EGR pipeline for preventing the backflow of the exhaust gas condensate water as claimed in claim 1, wherein the EGR pipeline interlayer (113) comprises an interlayer main body (1132), one end of the interlayer main body (1132) is press-fitted below the inner wall of the EGR pipeline by a press-fitting flange (1131), the interlayer main body (1132) is further provided with a plurality of rows of water discharging grate holes (1133), and each row of water discharging grate holes (1133) are arranged in a staggered manner and are used for most of the condensate water to flow into the EGR pipeline interlayer (113).

3. The EGR pipeline for preventing the backflow of exhaust gas condensate water as claimed in claim 1, wherein an electrically controlled drain valve (114) is further disposed below the inner wall of the EGR pipeline for draining excessive condensate water.