EP3421775A1 - Method for cleaning an exhaust gas recirculation line and/or an exhaust gas cooler and exhaust gas recirculation system - Google Patents
Method for cleaning an exhaust gas recirculation line and/or an exhaust gas cooler and exhaust gas recirculation system Download PDFInfo
- Publication number
- EP3421775A1 EP3421775A1 EP18179480.1A EP18179480A EP3421775A1 EP 3421775 A1 EP3421775 A1 EP 3421775A1 EP 18179480 A EP18179480 A EP 18179480A EP 3421775 A1 EP3421775 A1 EP 3421775A1
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- EP
- European Patent Office
- Prior art keywords
- exhaust gas
- gas recirculation
- recirculation line
- internal combustion
- combustion engine
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
- 238000000034 method Methods 0.000 title claims abstract description 45
- 238000004140 cleaning Methods 0.000 title claims abstract description 25
- 238000002485 combustion reaction Methods 0.000 claims abstract description 53
- 239000012530 fluid Substances 0.000 claims abstract description 20
- 238000011144 upstream manufacturing Methods 0.000 claims abstract description 16
- 239000012535 impurity Substances 0.000 claims abstract description 3
- 238000011010 flushing procedure Methods 0.000 claims description 30
- 239000003795 chemical substances by application Substances 0.000 claims description 11
- 239000003599 detergent Substances 0.000 claims description 9
- 238000002156 mixing Methods 0.000 claims description 5
- 230000007935 neutral effect Effects 0.000 claims description 5
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 239000007864 aqueous solution Substances 0.000 claims description 2
- 238000005406 washing Methods 0.000 claims description 2
- 238000010926 purge Methods 0.000 abstract description 7
- 239000000356 contaminant Substances 0.000 abstract description 2
- 239000007789 gas Substances 0.000 description 176
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 15
- 239000003054 catalyst Substances 0.000 description 13
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 6
- XSQUKJJJFZCRTK-UHFFFAOYSA-N Urea Chemical compound NC(N)=O XSQUKJJJFZCRTK-UHFFFAOYSA-N 0.000 description 5
- 239000004202 carbamide Substances 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 238000007789 sealing Methods 0.000 description 4
- 239000004071 soot Substances 0.000 description 4
- 206010053648 Vascular occlusion Diseases 0.000 description 3
- 229910021529 ammonia Inorganic materials 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 230000003197 catalytic effect Effects 0.000 description 2
- 238000010531 catalytic reduction reaction Methods 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 238000006722 reduction reaction Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000003638 chemical reducing agent Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 239000002826 coolant Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000011086 high cleaning Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 230000007257 malfunction Effects 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
- F02M26/22—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with coolers in the recirculation passage
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02B—INTERNAL-COMBUSTION PISTON ENGINES; COMBUSTION ENGINES IN GENERAL
- F02B77/00—Component parts, details or accessories, not otherwise provided for
- F02B77/04—Cleaning of, preventing corrosion or erosion in, or preventing unwanted deposits in, combustion engines
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/13—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories
- F02M26/36—Arrangement or layout of EGR passages, e.g. in relation to specific engine parts or for incorporation of accessories with means for adding fluids other than exhaust gas to the recirculation passage; with reformers
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/49—Detecting, diagnosing or indicating an abnormal function of the EGR system
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/50—Arrangements or methods for preventing or reducing deposits, corrosion or wear caused by impurities
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
- F28G15/00—Details
- F28G15/003—Control arrangements
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28G—CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OR BOILERS
- F28G9/00—Cleaning by flushing or washing, e.g. with chemical solvents
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M26/00—Engine-pertinent apparatus for adding exhaust gases to combustion-air, main fuel or fuel-air mixture, e.g. by exhaust gas recirculation [EGR] systems
- F02M26/02—EGR systems specially adapted for supercharged engines
Definitions
- the invention relates to a method for cleaning an exhaust gas recirculation line and an exhaust gas recirculation system with a flushing device according to the preamble of the independent claims.
- aqueous urea solution is used, which is mixed in a SCR catalyst upstream mixing device with the hot exhaust gas stream. By this mixing, the aqueous urea solution is heated, wherein the aqueous urea solution releases ammonia in the exhaust gas passage.
- a commercial aqueous urea solution generally consists of 32.5% urea and 67.5% water.
- One way to lower the raw emissions of an internal combustion engine is the return of exhaust gas in the fresh air tract of the internal combustion engine.
- the combustion temperature can be lowered in the combustion chambers of the internal combustion engine and thus in particular the nitrogen oxide formation can be reduced.
- high-pressure exhaust gas recirculation are known in which the exhaust gas immediately after an outlet of the Internal combustion engine discharged from the exhaust passage and the intake air is supplied immediately before entering the combustion chambers of the internal combustion engine.
- low-pressure exhaust gas recirculations are known, in which the exhaust gas of the internal combustion engine downstream of a turbine of the exhaust gas turbocharger and downstream of an exhaust aftertreatment component, in particular a particulate filter, tapped from the exhaust duct and the air supply system upstream of a compressor is supplied.
- an exhaust gas recirculation cooler is usually provided in a low-pressure exhaust gas recirculation, with which the exhaust gas temperature of the recirculated exhaust gas is reduced.
- deposits can form in the exhaust gas recirculation, which can reduce the line cross section of the exhaust gas recirculation line and can disturb the function of an exhaust gas recirculation valve. This can lead to individual components of the exhaust gas recirculation having to be replaced, because the components can not be cleaned without disassembly and functional reliability is no longer guaranteed.
- the object of the invention is to provide a cleaning method for an exhaust gas recirculation system, in which contamination and deposits from the exhaust gas recirculation can be reliably removed and which makes a costly and time-consuming replacement of soiled components superfluous.
- the cleaning of an exhaust gas recirculation line, an exhaust gas recirculation valve and / or an exhaust gas recirculation cooler is possible, so that deposits and sooting can be flushed out of the exhaust gas recirculation system without these components must be replaced.
- the exhaust gas recirculation passage is at least partially closed by a diaphragm or a plate, so that the exhaust gas volume guided through the exhaust gas recirculation line is increased.
- a closure is designed in the manner of a pressure relief valve to prevent damage to the exhaust system and to be able to reduce this pressure at an impermissible pressure increase in the exhaust system.
- the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler is determined and a method is initiated when the VersottungsPark has reached or exceeded a defined threshold for sooting.
- the flushing fluid is introduced into at least one of the openings while the internal combustion engine is running.
- a flushing pressure can be built up in a simple manner, which pushes the flushing fluid at high speed through the exhaust gas recirculation and thus allows efficient cleaning of the exhaust gas recirculation line, the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler.
- the internal combustion engine is operated during the cleaning process with a threshold speed, wherein the threshold speed is above an idle speed of the internal combustion engine. Due to a higher speed, the volume flow of exhaust gas through the exhaust gas recirculation line and the exhaust gas recirculation cooler can be increased.
- the threshold speed is preferably in the range between 1500 U / min and 4000 U / min, more preferably between 2000 U / min and 3000 U / min, for example 2500 U / min.
- the internal combustion engine is switched off when the flushing agent has been completely emptied into the exhaust gas recirculation line.
- the internal combustion engine is switched off when the flushing agent has been completely emptied into the exhaust gas recirculation line.
- the internal combustion engine is switched off after the complete emptying of the detergent, in particular a detergent bottle or a detergent can, the environmental impact of the service can be reduced.
- a shutdown of the internal combustion engine with a short delay of 1 s to 20 s, in particular from 2 s to 10 s, more preferably from about 5 s after the complete emptying of the rinsing agent is preferred to even the Spülfluidrest still with a corresponding gas flow through the Exhaust gas recirculation cooler to promote the exhaust gas recirculation valve and the exhaust gas recirculation line.
- the flushing fluid is an aqueous solution of a neutral detergent with a mixing ratio of 80 to 95 percent by volume of water and 5 to 20 percent by volume of neutral detergent. In such a Mixing ratio could be achieved in experiments a particularly good cleaning result with a limited Spülfluidminister.
- the flushing fluid is introduced into one of the openings at a pressure of 2 to 5 bar, in particular at a pressure of 3 bar.
- a flushing fluid which is under increased pressure in relation to the environment, a simple introduction of the flushing fluid into the exhaust gas recirculation line can be ensured.
- the pressure is built up in the flushing agent, in particular in the flushing agent bottle or the flushing agent canister, before it is connected to one of the openings on the exhaust gas recirculation line or the exhaust gas duct.
- the openings are closed during normal operation of the internal combustion engine in each case by a sensor, in particular by a temperature sensor or an actuator for an exhaust gas recirculation valve.
- an exhaust gas recirculation system for an internal combustion engine comprising at least one exhaust gas recirculation line and an exhaust gas recirculation cooler
- the exhaust gas recirculation system is adapted to carry out a method according to the invention for cleaning an exhaust gas recirculation line and / or an exhaust gas recirculation cooler, when a flushing agent is connected to an opening of the exhaust gas recirculation system.
- FIG. 1 an internal combustion engine 10 is shown with an air supply system and an exhaust system.
- a fresh gas line 16 is connected to an inlet 12 of the internal combustion engine 10.
- the internal combustion engine 10 is preferably designed as a self-igniting internal combustion engine 10 according to the diesel principle, but can also be designed as a spark-ignited internal combustion engine 10 according to the Otto principle.
- a compressor 18 of an exhaust gas turbocharger 34 and in the flow direction downstream of the compressor 18, a charge air cooler 20 are arranged.
- the exhaust 14 of the internal combustion engine 10 is connected to an exhaust passage 40 in which in the flow direction of an exhaust gas through the exhaust passage 40 downstream of the engine, a turbine 32 of the exhaust gas turbocharger 34, downstream of the turbine 32, a catalyst 36, in particular an oxidation catalyst or a NOx storage catalyst, and downstream of the catalyst 36, a particulate filter 38, in particular a particulate filter with a coating for the selective, catalytic reduction of nitrogen oxides, are arranged.
- a first differential pressure line 42 Upstream of the particulate filter 38 branches off a first differential pressure line 42 from the exhaust passage 40, which is connected to a differential pressure sensor 46. Downstream of the particulate filter 38, the exhaust passage 40 is connected via a second differential pressure line 44 to the differential pressure sensor 46, so that a pressure difference across the particulate filter 38 can be determined. This pressure difference can be used to determine the loading state of the particulate filter, so that the soot retained in the particulate filter 38 can be periodically burned off and the particulate filter 38 is released again.
- an exhaust gas recirculation line 26, 30 branches off the exhaust passage 40 and connects it to the fresh gas passage 16 downstream of the charge air cooler 20 and upstream of the inlet 12 of the engine 10.
- an exhaust gas recirculation cooler 28th and an exhaust gas recirculation valve, which is flowed through by a coolant of the internal combustion engine 10 and reduces the exhaust gas temperature of the recirculated via the exhaust gas recirculation line 26, 30 exhaust gas.
- an opening 54 is provided, to which an unillustrated temperature sensor can be connected.
- a further opening 56 for connection of a sensor in particular an exhaust gas sensor or a temperature sensor is provided.
- the exhaust gas through the catalyst 36 and the particulate filter 38 is cleaned via the exhaust duct 40 emitted to the environment.
- a subset of the exhaust gas is supplied via the exhaust gas recirculation line 26, 30 and the exhaust gas recirculation cooler 28 to the fresh gas channel 16 at least at certain operating points, so that the combustion temperature in the combustion chambers of the internal combustion engine 10 can be lowered and thus the nitrogen oxide emissions can be reduced .
- a sooting of the exhaust gas recirculation cooler 28, the exhaust gas recirculation valve and / or the exhaust gas recirculation line 26, 30 may occur.
- the internal combustion engine 10 is shown in a service mode for carrying out a method according to the invention for cleaning the exhaust gas recirculation line 26, 30, the exhaust gas recirculation valve and the exhaust gas recirculation cooler 28.
- the exhaust duct 40 is closed by a closure 48, in particular by a sealing plate.
- a first section 26 of the exhaust gas recirculation line 26, 30, which opens into the fresh gas line 16 downstream of the intercooler 20, separated from a second portion 30 of the exhaust gas recirculation line 26, 30 and the first portion 26 through a closure 24, in particular by a sealing plug or a Sealing plate, closed.
- the second section 30 of the exhaust gas recirculation line 26, 30 is, as in FIG. 3 shown connected to a washing container 50. Since the exhaust pipe 40 is closed, the complete exhaust gas flow is guided through the exhaust gas recirculation line 30 and the exhaust gas recirculation cooler 28 in the service operation. In this case, a flushing fluid 58 is supplied to the exhaust gas flow through one of the openings 54, 56, which is conveyed by the exhaust gas flow at high speed through the exhaust gas recirculation line 30, the exhaust gas recirculation valve and the exhaust gas recirculation cooler 28. This achieves a high cleaning performance.
- Arranged on the rinsing container 50 is an extraction funnel 52, with which the exhaust gas is sucked off after the rinsing fluid has been delivered to the rinsing container 50 and can be discharged accordingly.
- the method for cleaning the exhaust gas recirculation line 26, 30, the exhaust gas recirculation valve and the exhaust gas recirculation cooler 28 can also be based on FIG. 3 to explain.
- a first method step the soot condition of the exhaust gas recirculation cooler 28, the exhaust gas recirculation valve and the exhaust gas recirculation line 26, 30 is determined. If this sooting state lies above a defined threshold value for sooting, it is necessary to clean the exhaust gas recirculation system 26, 28, 30.
- a second method step initially the outlet opening is closed off from the exhaust gas channel 40 or the cross-section of the exhaust gas channel is reduced in order to increase an exhaust gas flow through the exhaust gas recirculation line 26, 30.
- a plate according to the principle of a pressure relief valve, so that damage to the Exhaust after-treatment components due to an impermissible pressure build-up in the exhaust system is avoided.
- the first section 26 of the exhaust gas recirculation line 26, 30 and the second section 30 of the exhaust gas recirculation line 26, 30 are separated from each other and the first section 26 is closed by a sealing plug.
- an exhaust gas recirculation valve is connected to the exhaust gas recirculation cooler 28 with a hose.
- a plug is removed from the exhaust gas recirculation valve and the exhaust gas recirculation valve is fixed in an open position.
- a temperature sensor in the exhaust gas recirculation line 30 upstream of the exhaust gas recirculation cooler 28 and upstream of the exhaust gas recirculation valve is removed, so that the opening 54 is exposed.
- a rinsing agent in particular a pressure rinsing bottle with a rinsing fluid based on an aqueous neutral detergent, filled.
- the Druck Hughesflasche is attached to the opening 54 and built an operating pressure of about 3 bar in the Druckêtflasche.
- the internal combustion engine 10 is started and accelerated to a purging speed of 2000 rpm to 3000 rpm, preferably 2500 rpm, wherein a check is made as to whether the exhaust passage 40 is actually closed by the closure 48 substantially gas-tight is.
- the flushing fluid is introduced from the pressure flushing bottle into the exhaust gas recirculation line 30, wherein the pressure in the pressure flushing bottle is tracked to avoid a pressure drop.
- the engine 10 is switched off after a short follow-up phase of 2 s - 10 s, preferably of about 5 s.
- another pressure rinse bottle can be connected to the exhaust gas recirculation line 30 and another rinse cycle can be performed.
- the purge process of the exhaust gas recirculation line 30 and the exhaust gas recirculation cooler 28 is completed successfully, the engine 10 is restored to the normal operation state.
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- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Exhaust-Gas Circulating Devices (AREA)
- Exhaust Gas After Treatment (AREA)
Abstract
Die Erfindung betrifft ein Verfahren zur Reinigung einer Abgasrückführungsleitung (26, 30) und/oder eines Abgasrückführungskühlers (28) an einem Verbrennungsmotor (10). Dabei wird zur Durchführung des Verfahrens der Abgasstrom durch den Abgaskanal (40) gedrosselt oder der Abgaskanal (40) durch einen Verschluss (48) verschlossen, sodass der Abgasstrom durch die Abgasrückführungsleitung (26, 30) erhöht wird oder der gesamte Abgasstrom des Verbrennungsmotors (10) durch die Abgasrückführungsleitung (26, 30) geleitet wird. Dazu wird ein erster Abschnitt (26) der Abgasrückführungsleitung (26, 30) zwischen einem Abgasrückführungskühler (28) und der Ladeluftstrecke von einem zweiten Abschnitt der Abgasrückführungsleitung (30), welcher den Abgaskanal (40) mit dem Abgasrückführungskühler (28) verbindet, getrennt und verschlossen, um ein Eindringen von Verunreinigungen in die Frischgasleitung (16) zu vermeiden. Das offene Ende des zweiten Abschnitts (30) der Abgasrückführungsleitung (26) wird mit einem Spülbehälter (50) verbunden. Anschließend wird der Verbrennungsmotor (10) gestartet und durch eine Öffnung (54) an der Abgasrückführungsleitung (30) in Spülrichtung stromaufwärts des Abgasrückführungskühlers (28) und stromaufwärts eines Abgasrückführungsventils ein Spülfluid in die Abgasrückführungsleitung (30) eingebracht, wobei der Abgasrückführungskühler (28) und die Abgasrückführungsleitung (30) von Verunreinigungen und Ablagerungen befreit werden. The invention relates to a method for cleaning an exhaust gas recirculation line (26, 30) and / or an exhaust gas recirculation cooler (28) on an internal combustion engine (10). In this case, the exhaust gas flow is throttled through the exhaust passage (40) or the exhaust passage (40) closed by a closure (48) so that the exhaust gas flow through the exhaust gas recirculation line (26, 30) is increased or the entire exhaust gas flow of the internal combustion engine (10 ) is passed through the exhaust gas recirculation line (26, 30). For this purpose, a first portion (26) of the exhaust gas recirculation line (26, 30) between an exhaust gas recirculation cooler (28) and the charge air path of a second portion of the exhaust gas recirculation line (30) which connects the exhaust passage (40) with the exhaust gas recirculation cooler (28) separated and closed to prevent ingress of contaminants in the fresh gas line (16). The open end of the second section (30) of the exhaust gas recirculation line (26) is connected to a purge tank (50). Subsequently, the internal combustion engine (10) is started and introduced through an opening (54) on the exhaust gas recirculation line (30) in the purge direction upstream of the exhaust gas recirculation cooler (28) and upstream of an exhaust gas recirculation valve, a purge fluid in the exhaust gas recirculation line (30), wherein the exhaust gas recirculation cooler (28) and the exhaust gas recirculation line (30) are freed of impurities and deposits.
Description
Die Erfindung betrifft ein Verfahren zur Reinigung einer Abgasrückführungsleitung sowie ein Abgasrückführungssystem mit einer Spüleinrichtung gemäß dem Oberbegriff der unabhängigen Patentansprüche.The invention relates to a method for cleaning an exhaust gas recirculation line and an exhaust gas recirculation system with a flushing device according to the preamble of the independent claims.
Die aktuelle und eine zukünftig immer schärfer werdende Abgasgesetzgebung stellen hohe Anforderungen an die motorischen Rohemissionen und die Abgasnachbehandlung von Verbrennungsmotoren. Dabei stellen die Forderungen nach einem weiter sinkenden Verbrauch und die weitere Verschärfung der Abgasnormen hinsichtlich der zulässigen StickoxidEmissionen eine Herausforderung für die Motorenentwickler dar. Bei Ottomotoren erfolgt die Abgasreinigung in bekannter Weise über einen Drei-Wege-Katalysator, sowie dem Drei-Wege-Katalysator vor- und nachgeschaltete weitere Katalysatoren. Bei Dieselmotoren finden aktuell Abgasnachbehandlungssysteme Verwendung, welche einen Oxidationskatalysator oder NOx-Speicherkatalysator, einen Katalysator zur selektiven katalytischen Reduktion von Stickoxiden (SCR-Katalysator) sowie einen Partikelfilter zur Abscheidung von Rußpartikeln und gegebenenfalls weitere Katalysatoren aufweisen. Als Reduktionsmittel wird dabei bevorzugt Ammoniak verwendet. Weil der Umgang mit reinem Ammoniak aufwendig ist, wird bei Fahrzeugen üblicherweise eine synthetische, wässrige Harnstofflösung verwendet, die in einer dem SCR-Katalysator vorgeschalteten Mischeinrichtung mit dem heißen Abgasstrom vermischt wird. Durch diese Vermischung wird die wässrige Harnstofflösung erhitzt, wobei die wässrige Harnstofflösung Ammoniak im Abgaskanal freisetzt. Eine handelsübliche, wässrige Harnstofflösung setzt sind im Allgemeinen aus 32,5 % Harnstoff und 67,5 % Wasser zusammen.The current and increasingly stringent future exhaust gas legislation places high demands on the engine raw emissions and the exhaust aftertreatment of internal combustion engines. The demands for a further reduction in consumption and the further tightening of emission standards with regard to permissible nitrogen oxide emissions pose a challenge to engine developers. In gasoline engines, exhaust gas purification takes place in a known manner via a three-way catalytic converter and the three-way catalytic converter - And downstream further catalysts. For diesel engines exhaust gas aftertreatment systems are currently used, which have an oxidation catalyst or NOx storage catalyst, a catalyst for the selective catalytic reduction of nitrogen oxides (SCR catalyst) and a particulate filter for the separation of soot particles and optionally other catalysts. The reducing agent used is preferably ammonia. Because the handling of pure ammonia is complicated, in vehicles usually a synthetic, aqueous urea solution is used, which is mixed in a SCR catalyst upstream mixing device with the hot exhaust gas stream. By this mixing, the aqueous urea solution is heated, wherein the aqueous urea solution releases ammonia in the exhaust gas passage. A commercial aqueous urea solution generally consists of 32.5% urea and 67.5% water.
Eine Möglichkeit die Rohemissionen eines Verbrennungsmotors abzusenken ist die Rückführung von Abgas in den Frischlufttrakt des Verbrennungsmotors. Dadurch kann die Verbrennungstemperatur in den Brennräumen des Verbrennungsmotors abgesenkt und somit insbesondere die Stickoxidbildung vermindert werden. Dabei sind Hochdruck-Abgasrückführungen bekannt, bei denen das Abgas unmittelbar nach einem Auslass des Verbrennungsmotors aus dem Abgaskanal abgeführt und der Ansaugluft unmittelbar vor Eintritt in die Brennräume des Verbrennungsmotors zugeführt wird. Darüber hinaus sind Niederdruck-Abgasrückführungen bekannt, bei denen das Abgas des Verbrennungsmotors stromabwärts einer Turbine des Abgasturboladers und stromabwärts einer Abgasnachbehandlungskomponente, insbesondere eines Partikelfilters, aus dem Abgaskanal abgezapft und dem Luftversorgungssystem stromaufwärts eines Verdichters zugeführt wird. Dabei ist in einer Niederdruck-Abgasrückführung in der Regel ein Abgasrückführungskühler vorgesehen, mit welchem die Abgastemperatur des zurückgeführten Abgases reduziert wird.One way to lower the raw emissions of an internal combustion engine is the return of exhaust gas in the fresh air tract of the internal combustion engine. Thereby, the combustion temperature can be lowered in the combustion chambers of the internal combustion engine and thus in particular the nitrogen oxide formation can be reduced. In this case, high-pressure exhaust gas recirculation are known in which the exhaust gas immediately after an outlet of the Internal combustion engine discharged from the exhaust passage and the intake air is supplied immediately before entering the combustion chambers of the internal combustion engine. In addition, low-pressure exhaust gas recirculations are known, in which the exhaust gas of the internal combustion engine downstream of a turbine of the exhaust gas turbocharger and downstream of an exhaust aftertreatment component, in particular a particulate filter, tapped from the exhaust duct and the air supply system upstream of a compressor is supplied. In this case, an exhaust gas recirculation cooler is usually provided in a low-pressure exhaust gas recirculation, with which the exhaust gas temperature of the recirculated exhaust gas is reduced.
Im Betrieb des Verbrennungsmotors können sich in der Abgasrückführung Ablagerungen bilden, welche den Leitungsquerschnitt der Abgasrückführungsleitung verringern können und die Funktion eines Abgasrückführungsventils stören können. Dies kann dazu führen, dass einzelne Bauteile der Abgasrückführung ausgetauscht werden müssen, weil die Komponenten ohne eine Demontage nicht gereinigt werden können und die Funktionssicherheit nicht mehr gewährleistet ist.During operation of the internal combustion engine, deposits can form in the exhaust gas recirculation, which can reduce the line cross section of the exhaust gas recirculation line and can disturb the function of an exhaust gas recirculation valve. This can lead to individual components of the exhaust gas recirculation having to be replaced, because the components can not be cleaned without disassembly and functional reliability is no longer guaranteed.
Aus der
Aufgabe der Erfindung ist es, ein Reinigungsverfahren für ein Abgasrückführungssystem bereitzustellen, bei dem Verschmutzungen und Ablagerungen aus der Abgasrückführung zuverlässig entfernt werden können und welches einen kosten- und zeitintensiven Austausch von verschmutzten Komponenten überflüssig macht.The object of the invention is to provide a cleaning method for an exhaust gas recirculation system, in which contamination and deposits from the exhaust gas recirculation can be reliably removed and which makes a costly and time-consuming replacement of soiled components superfluous.
Erfindungsgemäß wird die Aufgabe durch ein Verfahren zur Reinigung einer Abgasrückführungsleitung und/oder eines Abgasrückführungskühlers an einem Verbrennungsmotor gelöst, welches folgende Schritte umfasst:
- Drosseln eines Abgasstroms durch den Abgaskanal oder Verschließen des Abgaskanals durch einen Verschluss, sodass das durch den Abgasrückführungskanal geleitete Abgasvolumen erhöht wird,
- Trennen der ersten Abgasrückführungsleitung von der zweiten Abgasrückführungsleitung,
- Verschließen des offenen Endes der ersten Abgasrückführungsleitung durch einen weiteren Verschluss, sodass ein Eintrag in das Luftversorgungssystem des Verbrennungsmotors unterbunden wird,
- Verbinden des offenen Endes der zweiten Abgasrückführungsleitung mit einem Spülbehälter,
- Anschluss eines Spülmittels an eine Öffnung an der Abgasrückführungsleitung oder dem Abgaskanal in Spülrichtung stromaufwärts eines Abgasrückführungskühlers und stromaufwärts eines Abgasrückführungsventils der Abgasrückführungsleitung,
- Einbringen eines Spülfluids in die Abgasrückführungsleitung, wobei der Abgasrückführungskühler, das Abgasrückführungsventil und die Abgasrückführungsleitung von Verunreinigungen und Ablagerungen befreit werden.
- Throttling an exhaust gas flow through the exhaust passage or closing the exhaust passage through a shutter so as to increase the exhaust gas volume routed through the exhaust gas recirculation passage;
- Separating the first exhaust gas recirculation line from the second exhaust gas recirculation line,
- Closing the open end of the first exhaust gas recirculation line by a further closure, so that an entry in the air supply system of the internal combustion engine is prevented,
- Connecting the open end of the second exhaust gas recirculation line to a purge container,
- Connecting a rinsing agent to an opening on the exhaust gas recirculation line or the exhaust passage in the purge direction upstream of an exhaust gas recirculation cooler and upstream of an exhaust gas recirculation valve of the exhaust gas recirculation line,
- Introducing a flushing fluid into the exhaust gas recirculation line, wherein the exhaust gas recirculation cooler, the exhaust gas recirculation valve and the exhaust gas recirculation line are freed from impurities and deposits.
Durch ein erfindungsgemäßes Verfahren ist die Reinigung einer Abgasrückführungsleitung, eines Abgasrückführungsventils und/oder eines Abgasrückführungskühlers möglich, sodass Ablagerungen und Versottungen aus dem Abgasrückführungssystem herausgespült werden können, ohne dass diese Bauteile ausgetauscht werden müssen. Dadurch ist ein einfacher Service möglich, wodurch in der Wartung und Instandhaltung des Kraftfahrzeuges Zeit und Geld eingespart werden können. Dabei wird der Abgasrückführungskanal durch eine Blende oder eine Platte zumindest abschnittsweise verschlossen, sodass das durch die Abgasrückführungsleitung geführt Abgasvolumen vergrößert wird. Bevorzugt ist ein Verschluss nach Art eines Druckbegrenzungsventils ausgeführt, um eine Beschädigung der Abgasanlage zu vermeiden und bei einem unzulässigen Druckanstieg in der Abgasanlage diesen Druck abbauen zu können.By an inventive method, the cleaning of an exhaust gas recirculation line, an exhaust gas recirculation valve and / or an exhaust gas recirculation cooler is possible, so that deposits and sooting can be flushed out of the exhaust gas recirculation system without these components must be replaced. As a result, a simple service is possible, which in the maintenance and repair of the vehicle time and money can be saved. In this case, the exhaust gas recirculation passage is at least partially closed by a diaphragm or a plate, so that the exhaust gas volume guided through the exhaust gas recirculation line is increased. Preferably, a closure is designed in the manner of a pressure relief valve to prevent damage to the exhaust system and to be able to reduce this pressure at an impermissible pressure increase in the exhaust system.
Durch die in den abhängigen Ansprüchen aufgeführten Merkmale sind vorteilhafte Verbesserungen und Weiterentwicklungen des im unabhängigen Anspruch angegebenen Verfahrens zur Reinigung einer Abgasrückführungsleitung oder eines Abgasrückführungskühlers möglich.The features listed in the dependent claims advantageous improvements and developments of the independent claim specified method for cleaning an exhaust gas recirculation line or an exhaust gas recirculation cooler are possible.
In einer bevorzugten Ausführungsform der Erfindung ist vorgesehen, dass vor dem Durchführen einer Abgasrückführungsreinigung der Versottungszustand der Abgasrückführungsleitung, des Abgasrückführungsventils und/oder des Abgasrückführungskühlers ermittelt wird und ein Verfahren eingeleitet wird, wenn der Versottungszustand einen definierten Schwellenwert für die Versottung erreicht oder überschritten hat. Durch eine gezielte Ermittlung des Ausgangszustands kann eine bedarfsgerechte Reinigung des Abgasrückführungssystems erfolgen. Dabei müssen keine festen Serviceintervalle eingehalten werden, sondern es kann in Abhängigkeit von einer real auftretenden Verschmutzung oder Versottung entschieden werden, ob ein definierter Schwellenwert für die Versottung erreicht ist und dementsprechend eine Reinigung der Abgasrückführungsleitung, des Abgasrückführungsventils und/oder des Abgasrückführungskühlers notwendig ist.In a preferred embodiment of the invention it is provided that prior to performing an exhaust gas recirculation cleaning the Versottungszustand the exhaust gas recirculation line, the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler is determined and a method is initiated when the Versottungszustand has reached or exceeded a defined threshold for sooting. By a specific determination of the initial state, a demand-based cleaning of the exhaust gas recirculation system can take place. In this case, no fixed service intervals must be complied with, but it can in Depending on a pollution or sooting that occurs in reality, a decision is made as to whether a defined erosion threshold is reached and, accordingly, a cleaning of the exhaust gas recirculation line, the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler is necessary.
Bevorzugt ist dabei, wenn das Spülfluid bei laufendem Verbrennungsmotor in zumindest eine der Öffnungen eingebracht wird. Durch einen laufenden Motorbetrieb kann auf einfache Art und Weise ein Spüldruck aufgebaut werden, welcher das Spülfluid mit hoher Geschwindigkeit durch die Abgasrückführung drückt und somit eine effiziente Reinigung der Abgasrückführungsleitung, des Abgasrückführungsventils und/oder des Abgasrückführungskühlers ermöglicht.It is preferred if the flushing fluid is introduced into at least one of the openings while the internal combustion engine is running. By a running engine operation, a flushing pressure can be built up in a simple manner, which pushes the flushing fluid at high speed through the exhaust gas recirculation and thus allows efficient cleaning of the exhaust gas recirculation line, the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler.
Besonders bevorzugt ist dabei, wenn der Verbrennungsmotor während des Reinigungsvorgangs mit einer Schwellendrehzahl betrieben wird, wobei die Schwellendrehzahl oberhalb einer Leerlaufdrehzahl des Verbrennungsmotors liegt. Durch eine höhere Drehzahl kann der Volumenstrom an Abgas durch die Abgasrückführungsleitung und den Abgasrückführungskühler erhöht werden. Dabei liegt die Schwellendrehzahl vorzugsweise im Bereich zwischen 1500 U/min und 4000 U/min, besonders bevorzugt zwischen 2000 U/min und 3000 U/min, beispielsweise 2500 U/min. Durch den hohen Abgasstrom wird verhindert, dass nach dem Reinigungsverfahren Spülfluidreste in der Abgasrückführungsleitung, dem Abgasrückführungsventil oder dem Abgasrückführungskühler zurückbleiben, welche ebenfalls negativen Einfluss auf die Funktion des Abgasrückführungssystems haben können.It is particularly preferred if the internal combustion engine is operated during the cleaning process with a threshold speed, wherein the threshold speed is above an idle speed of the internal combustion engine. Due to a higher speed, the volume flow of exhaust gas through the exhaust gas recirculation line and the exhaust gas recirculation cooler can be increased. The threshold speed is preferably in the range between 1500 U / min and 4000 U / min, more preferably between 2000 U / min and 3000 U / min, for example 2500 U / min. Due to the high exhaust gas flow prevents after the cleaning process Spülfluidreste in the exhaust gas recirculation line, the exhaust gas recirculation valve or the exhaust gas recirculation cooler left behind, which can also have a negative impact on the function of the exhaust gas recirculation system.
In einer weiteren Verbesserung des Verfahrens ist vorgesehen, dass der Verbrennungsmotor abgeschaltet wird, wenn das Spülmittel vollständig in die Abgasrückführungsleitung entleert wurde. Durch ein Abschalten des Verbrennungsmotors nach dem vollständigen Entleeren des Spülmittels, insbesondere einer Spülmittelflasche oder eines Spülmittelkanisters kann die Umweltbelastung beim Service reduziert werden. Dabei ist eine Abschaltung des Verbrennungsmotors mit einer kurzen Verzögerung von 1 s bis 20 s, insbesondere von 2 s bis 10 s, besonders bevorzugt von etwa 5 s nach dem vollständigen Entleeren des Spülmittels bevorzugt, um auch den Spülfluidrest noch mit einem entsprechenden Gasstrom durch den Abgasrückführungskühler, das Abgasrückführungsventil und die Abgasrückführungsleitung zu fördern.In a further improvement of the method, it is provided that the internal combustion engine is switched off when the flushing agent has been completely emptied into the exhaust gas recirculation line. By switching off the internal combustion engine after the complete emptying of the detergent, in particular a detergent bottle or a detergent can, the environmental impact of the service can be reduced. Here, a shutdown of the internal combustion engine with a short delay of 1 s to 20 s, in particular from 2 s to 10 s, more preferably from about 5 s after the complete emptying of the rinsing agent is preferred to even the Spülfluidrest still with a corresponding gas flow through the Exhaust gas recirculation cooler to promote the exhaust gas recirculation valve and the exhaust gas recirculation line.
In einer bevorzugten Ausführungsform des Verfahrens ist vorgesehen, dass das Spülfluid eine wässrige Lösung eines Neutralreinigers mit einem Mischungsverhältnis von 80 bis 95 Volumenprozent Wasser und 5 bis 20 Volumenprozent Neutralreiniger ist. Bei einem solchen Mischungsverhältnis konnte in Experimenten ein besonders gutes Reinigungsergebnis bei einem begrenzten Spülfluideinsatz erreicht werden.In a preferred embodiment of the method it is provided that the flushing fluid is an aqueous solution of a neutral detergent with a mixing ratio of 80 to 95 percent by volume of water and 5 to 20 percent by volume of neutral detergent. In such a Mixing ratio could be achieved in experiments a particularly good cleaning result with a limited Spülfluideinsatz.
Gemäß einer bevorzugten Ausführungsform des Erfindung ist vorgesehen, dass das Spülfluid mit einem Druck von 2 - 5 bar, insbesondere mit einem Druck von 3 bar, in eine der Öffnungen eingebracht wird. Durch ein unter einem gegenüber der Umgebung unter erhöhtem Druck stehenden Spülfluid kann ein einfaches Einbringen des Spülfluids in die Abgasrückführungsleitung gewährleistet werden. Dabei wird der Druck in dem Spülmittel, insbesondere in der Spülmittelflasche oder dem Spülmittelkanister aufgebaut, bevor dieser an eine der Öffnungen an der Abgasrückführungsleitung oder dem Abgaskanal angeschlossen wird.According to a preferred embodiment of the invention, it is provided that the flushing fluid is introduced into one of the openings at a pressure of 2 to 5 bar, in particular at a pressure of 3 bar. By means of a flushing fluid which is under increased pressure in relation to the environment, a simple introduction of the flushing fluid into the exhaust gas recirculation line can be ensured. In this case, the pressure is built up in the flushing agent, in particular in the flushing agent bottle or the flushing agent canister, before it is connected to one of the openings on the exhaust gas recirculation line or the exhaust gas duct.
In einer vorteilhaften Ausführungsform der Erfindung ist vorgesehen, dass die Öffnungen im Normalbetrieb des Verbrennungsmotors jeweils durch einen Sensor, insbesondere durch einen Temperatursensor oder einen Aktuator für ein Abgasrückführungsventil verschlossen sind. Durch die Verwendung von bereits an der Abgasrückführungsleitung oder dem Abgaskanal vorhandenen Öffnungen sind keine zusätzlichen Serviceöffnungen für das Einbringen von dem Spülfluid notwendig. Zudem kann durch die zur Offenlegung der Öffnungen notwendige Demontage der Sensoren sichergestellt werden, dass diese Sensoren durch das Spülfluid während des Reinigungsverfahrens nicht beschädigt werden.In an advantageous embodiment of the invention it is provided that the openings are closed during normal operation of the internal combustion engine in each case by a sensor, in particular by a temperature sensor or an actuator for an exhaust gas recirculation valve. By using already existing at the exhaust gas recirculation line or the exhaust duct openings no additional service openings for the introduction of the flushing fluid are necessary. In addition, it can be ensured by the necessary for the disclosure of the openings disassembly of the sensors that these sensors are not damaged by the flushing fluid during the cleaning process.
In einer weiteren Verbesserung des Verfahrens ist vorgesehen, dass nach einem Spülvorgang die Restversottung der Abgasrückführungsleitung, des Abgasrückführungsventils und/oder des Abgasrückführungskühlers gemessen wird und das Verfahren solange wiederholt wird, bis die Restversottung unter einem zulässigen Schwellenwert liegt. Durch eine Überprüfung des Reinigungserfolgs kann eine bedarfsgerechte Einbringung von Spülfluid erfolgen, sodass die Menge an Spülfluid entsprechend erhöht oder reduziert werden kann. Dies führt zu einer Verringerung des Spülfluideinsatzes, da nicht immer der Einsatz einer maximalen Spülmittelmenge notwendig ist.In a further improvement of the method, it is provided that after a rinsing process the residual scorching of the exhaust gas recirculation line, the exhaust gas recirculation valve and / or the exhaust gas recirculation cooler is measured and the process is repeated until the residual scorching is below an admissible threshold value. By reviewing the cleaning success, a demand-based introduction of flushing fluid can take place, so that the amount of flushing fluid can be correspondingly increased or reduced. This leads to a reduction in the Spülfluideinsatzes, since it is not always necessary to use a maximum amount of detergent.
Erfindungsgemäß wird ein Abgasrückführungssystem für einen Verbrennungsmotor, umfassend mindestens eine Abgasrückführungsleitung und einen Abgasrückführungskühler vorgeschlagen, wobei das Abgasrückführungssystem dazu eingerichtet ist, ein erfindungsgemäßes Verfahren zur Reinigung einer Abgasrückführungsleitung und/oder eines Abgasrückführungskühlers durchzuführen, wenn ein Spülmittel an eine Öffnung des Abgasrückführungssystems angeschlossen wird. Durch ein erfindungsgemäßes Abgasrückführungssystem mit einer Abgasrückführungsleitung und einem Abgasrückführungskühler wird auf einfache Art und Weise die Durchführung eines erfindungsgemäßen Verfahrens ermöglicht.According to the invention, an exhaust gas recirculation system for an internal combustion engine comprising at least one exhaust gas recirculation line and an exhaust gas recirculation cooler is proposed, wherein the exhaust gas recirculation system is adapted to carry out a method according to the invention for cleaning an exhaust gas recirculation line and / or an exhaust gas recirculation cooler, when a flushing agent is connected to an opening of the exhaust gas recirculation system. By an inventive exhaust gas recirculation system with a Exhaust gas recirculation line and an exhaust gas recirculation cooler is made possible in a simple manner to carry out a method according to the invention.
Die verschiedenen in dieser Anmeldung genannten Ausführungsformen der Erfindung sind, sofern im Einzelfall nicht anders ausgeführt, mit Vorteil miteinander kombinierbar.The various embodiments of the invention mentioned in this application are, unless otherwise stated in the individual case, advantageously combinable with each other.
Die Erfindung wird nachfolgend in Ausführungsbeispielen anhand der zugehörigen Zeichnungen erläutert. Gleiche Bauteile oder Bauteile mit gleicher Funktion sind dabei mit den gleichen Bezugszeichen gekennzeichnet. Es zeigen:
- Figur 1
- einen Verbrennungsmotor mit einem Frischluftsystem und einer Abgasanlage, wobei die Abgasanlage über eine Abgasrückführleitung mit dem Frischluftsystem verbunden ist;
- Figur 2
- den Verbrennungsmotor, wobei zur Reinigung des Abgasrückführungssystems die Einleitung von Abgas in das Frischluftsystem unterbunden ist und der Abgaskanal durch einen Verschluss verschlossen ist; und
- Figur 3
- den Verbrennungsmotor, wobei an dem Verbrennungsmotor ein erfindungsgemäßes Verfahren zur Reinigung einer Abgasrückführungsleitung und/oder eines Abgasrückführungskühlers durchgeführt wird.
- FIG. 1
- an internal combustion engine with a fresh air system and an exhaust system, wherein the exhaust system is connected via an exhaust gas recirculation line to the fresh air system;
- FIG. 2
- the internal combustion engine, wherein for the purification of the exhaust gas recirculation system, the introduction of exhaust gas is prevented in the fresh air system and the exhaust duct is closed by a closure; and
- FIG. 3
- the internal combustion engine, wherein an inventive method for cleaning an exhaust gas recirculation line and / or an exhaust gas recirculation cooler is performed on the internal combustion engine.
In
Stromaufwärts des Partikelfilters 38 zweigt eine erste Differenzdruckleitung 42 aus dem Abgaskanal 40 ab, welche mit einem Differenzdrucksensor 46 verbunden ist. Stromabwärts des Partikelfilters 38 ist der Abgaskanal 40 über eine zweite Differenzdruckleitung 44 mit dem Differenzdrucksensor 46 verbunden, sodass eine Druckdifferenz über den Partikelfilter 38 ermittelt werden kann. Diese Druckdifferenz kann zur Ermittlung des Beladungszustandes des Partikelfilters genutzt werden, sodass der im Partikelfilter 38 zurückgehaltene Ruß periodisch abgebrannt werden kann und den Partikelfilter 38 wieder freisetzt.Upstream of the
Stromabwärts des Auslasses 14 und stromaufwärts der Turbine 32 zweigt eine Abgasrückführungsleitung 26, 30 aus dem Abgaskanal 40 ab und verbindet diesen mit dem Frischgaskanal 16 stromabwärts des Ladeluftkühlers 20 und stromaufwärts des Einlasses 12 des Verbrennungsmotors 10. In der Abgasrückführungsleitung 26, 30 sind ein Abgasrückführungskühler 28 und ein Abgasrückführungsventil angeordnet, welcher von einem Kühlmittel des Verbrennungsmotors 10 durchströmt wird und die Abgastemperatur des über die Abgasrückführungsleitung 26, 30 zurückgeführten Abgases reduziert. An der Abgasrückführungsleitung 30 ist stromabwärts einer Verzweigung von dem Abgaskanal 40 und stromaufwärts des Abgasrückführungskühlers 28 und stromaufwärts des Abgasrückführungsventils eine Öffnung 54 vorgesehen, an welche ein nicht dargestellter Temperatursensor angeschlossen werden kann. An dem Abgaskanal 40 ist stromabwärts des Auslasses 14 und stromaufwärts der Turbine 32 des Abgasturboladers 34 eine weitere Öffnung 56 zum Anschluss eines Sensors, insbesondere eines Abgassensors oder eines Temperatursensors vorgesehen.Downstream of the
In dem in
In
Das Verfahren zur Reinigung der Abgasrückführungsleitung 26, 30, des Abgasrückführungsventils sowie des Abgasrückführungskühlers 28 lässt sich ebenfalls anhand von
In einem folgenden Verfahrensschritt wird der Verbrennungsmotor 10 gestartet und auf eine Spüldrehzahl von 2000 U/min bis 3000 U/min, vorzugsweise von 2500 U/min beschleunigt, wobei eine Überprüfung erfolgt, ob der Abgaskanal 40 tatsächlich durch den Verschluss 48 im Wesentlichen gasdicht verschlossen ist. Bei im Wesentlichen konstanter Spüldrehzahl des Verbrennungsmotors 10 wird das Spülfluid von der Druckspülflasche in die Abgasrückführungsleitung 30 eingebracht, wobei der Druck in der Druckspülflasche nachgeführt wird, um einen Druckabfall zu vermeiden. Nachdem die Druckspülflasche vollständig entleert ist, wird der Verbrennungsmotor 10 nach einer kurzen Nachlaufphase von 2 s - 10 s, vorzugsweise von etwa 5 s abgeschaltet. Bei Bedarf kann eine weitere Druckspülflasche an die Abgasrückführungsleitung 30 angeschlossen werden und ein weiterer Spülzyklus durchgeführt werden. Ist der Spülprozess der Abgasrückführungsleitung 30 und des Abgasrückführungskühlers 28 erfolgreich abgeschlossen, so wird der Verbrennungsmotor 10 wieder in den Zustand für den Normalbetrieb zurückversetzt.In a subsequent method step, the
- 1010
- Verbrennungsmotorinternal combustion engine
- 1212
- Einlassinlet
- 1414
- Auslassoutlet
- 1616
- FrischgasleitungFresh gas line
- 1818
- Verdichtercompressor
- 2020
- LadeluftkühlerIntercooler
- 2222
- Einmündungjunction
- 2424
- Verschlussshutter
- 2626
- AbgasrückführungsleitungExhaust gas recirculation line
- 2828
- AbgasrückführungskühlerExhaust gas recirculation cooler
- 3030
- AbgasrückführungsleitungExhaust gas recirculation line
- 3232
- Turbineturbine
- 3434
- Abgasturboladerturbocharger
- 3636
- Oxidationskatalysatoroxidation catalyst
- 3838
- Partikelfilterparticulate Filter
- 4040
- Abgaskanalexhaust duct
- 4242
- DifferenzdruckleitungDifferential pressure line
- 4444
- DifferenzdruckleitungDifferential pressure line
- 4646
- DifferenzdrucksensorDifferential Pressure Sensor
- 4848
- Verschlussshutter
- 5050
- Spülbehälterrinse tank
- 5252
- Absaugtrichtersuction funnel
- 5454
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Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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DE102017114694.6A DE102017114694A1 (en) | 2017-06-30 | 2017-06-30 | Method for cleaning an exhaust gas recirculation line and / or an exhaust gas recirculation cooler and exhaust gas recirculation system |
Publications (2)
Publication Number | Publication Date |
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EP3421775A1 true EP3421775A1 (en) | 2019-01-02 |
EP3421775B1 EP3421775B1 (en) | 2020-09-30 |
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EP18179480.1A Active EP3421775B1 (en) | 2017-06-30 | 2018-06-25 | Method for cleaning an exhaust gas recirculation line and/or an exhaust gas recircvulation cooler |
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EP (1) | EP3421775B1 (en) |
DE (1) | DE102017114694A1 (en) |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6478036B1 (en) * | 1998-12-10 | 2002-11-12 | Bg Products, Inc. | Method and apparatus for cleaning exhaust gas recirculation system |
FR2885178A1 (en) * | 2005-04-27 | 2006-11-03 | Renault Sas | Power train for motor vehicle, has exhaust gas recirculation valves and back pressure valve circulating exhaust gas in cleaning circuit and evacuating gas in exhaust pipe, where circuit cleans section of exhaust gas recirculation circuit |
US20140331954A1 (en) * | 2013-05-07 | 2014-11-13 | Bg Intellectuals, Inc. | Cleaning formula for motor vehicle intake and exhaust systems |
DE102014001457A1 (en) * | 2014-02-05 | 2015-03-05 | Mtu Friedrichshafen Gmbh | Method and device for cleaning a heat exchanger, in particular an exhaust gas recooler for cooling an exhaust gas flow of an exhaust gas recirculation |
DE102015119204A1 (en) * | 2014-11-11 | 2016-05-12 | Ford Global Technologies, Llc | METHOD AND SYSTEM FOR EGR CONTROL |
JP2017031816A (en) * | 2015-07-29 | 2017-02-09 | いすゞ自動車株式会社 | Engine, and cleaning method of egr cooler of engine |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE602005013587D1 (en) | 2005-11-29 | 2009-05-07 | Renault Trucks | EXHAUST GAS RECYCLING SYSTEM AND METHOD FOR CLEANING SUCH A SYSTEM |
JP2017031815A (en) * | 2015-07-29 | 2017-02-09 | いすゞ自動車株式会社 | Engine egr cooler and method of washing egr cooler |
-
2017
- 2017-06-30 DE DE102017114694.6A patent/DE102017114694A1/en not_active Withdrawn
-
2018
- 2018-06-25 EP EP18179480.1A patent/EP3421775B1/en active Active
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6478036B1 (en) * | 1998-12-10 | 2002-11-12 | Bg Products, Inc. | Method and apparatus for cleaning exhaust gas recirculation system |
FR2885178A1 (en) * | 2005-04-27 | 2006-11-03 | Renault Sas | Power train for motor vehicle, has exhaust gas recirculation valves and back pressure valve circulating exhaust gas in cleaning circuit and evacuating gas in exhaust pipe, where circuit cleans section of exhaust gas recirculation circuit |
US20140331954A1 (en) * | 2013-05-07 | 2014-11-13 | Bg Intellectuals, Inc. | Cleaning formula for motor vehicle intake and exhaust systems |
DE102014001457A1 (en) * | 2014-02-05 | 2015-03-05 | Mtu Friedrichshafen Gmbh | Method and device for cleaning a heat exchanger, in particular an exhaust gas recooler for cooling an exhaust gas flow of an exhaust gas recirculation |
DE102015119204A1 (en) * | 2014-11-11 | 2016-05-12 | Ford Global Technologies, Llc | METHOD AND SYSTEM FOR EGR CONTROL |
JP2017031816A (en) * | 2015-07-29 | 2017-02-09 | いすゞ自動車株式会社 | Engine, and cleaning method of egr cooler of engine |
Also Published As
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EP3421775B1 (en) | 2020-09-30 |
DE102017114694A1 (en) | 2019-01-03 |
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