A method for rapid pressure stabilization detection of vehicle aftertreatment sealing performance in the National VI vehicle emission test

Abstract

The present invention provides a method for rapid detection of the sealing voltage stabilization of the vehicle aftertreatment in the National VI vehicle emission test, and relates to the field of vehicle testing technology. The method for rapid detection of the sealing voltage stabilization of the vehicle aftertreatment in the National VI vehicle emission test comprises the following steps: Step 1, vehicle inspection. Before conducting a vehicle leak test, a vehicle inspection is first conducted, and the process is as follows: S1. Check whether the vehicle's three-way catalytic converter and the engine cylinder exhaust are installed with sealing gaskets, and the screws are tightened according to the torque; S2. Check whether the front oxygen sensor and the rear oxygen sensor of the three-way catalytic converter accessory are coated with anti-sintering glue, and tightened according to the torque requirements. In the present invention, by keeping the pressure constant and uniform during the aftertreatment sealing test of each test vehicle, and by using a quick-insert mechanical design method for the compressed air connection with a valve, the entire leak test can be operated independently with safety standards throughout the entire process, avoiding human operation errors, and the new operation method is simple and easy to implement.

Description

Technical Field

[0001] The present invention relates to the technical field of whole vehicle testing, and in particular to a method for rapid pressure stabilization detection of vehicle post-processing sealing performance in a National VI whole vehicle emission test. Background Art

[0002] Before the whole vehicle emission test on the drum test bench, the sealing of the test vehicle's after-treatment system must be checked. The after-treatment includes the exhaust manifold, three-way catalytic converter, GPF, and automobile muffler of the engine exhaust system. The entire system is fastened with high-temperature resistant sealing gaskets through bolts. There must be no leakage in any part of each fastening point, component joint, sensor joint pipeline, etc. If leakage occurs, the test detection results will be invalid, the test data repeatability will be poor, and ultimately the experiment will fail.

[0003] The original method for testing the sealing of emission test vehicles is that the operator inserts the outlet end of the compressed air pipeline directly into the car muffler, blocks the other holes of the muffler compression pipeline, and allows the compressed air to enter the vehicle's after-treatment system. Another operator sprays foam on each connection point to check for gas leaks. Since the pressure for checking leaks is high, the operator's manual sealing operation is unstable and the pressure fluctuation is large, the leakage volume of each part does not meet the actual required leak test pressure, resulting in damage to parts due to excessive tightening, and an overheated exhaust pipe will cause a risk of burns.

[0004] Therefore, those skilled in the art provide a method for rapid pressure stabilization detection of vehicle aftertreatment sealing performance in the National VI vehicle emission test to solve the problems raised in the above-mentioned background technology. Summary of the invention

[0005] 1. Technical issues to be solved

[0006] In view of the deficiencies in the prior art, the present invention provides a method for rapid pressure-stabilizing detection of vehicle after-treatment sealing performance in a National VI whole vehicle emission test. By maintaining a constant and uniform pressure during the after-treatment sealing test of each test vehicle and adopting a quick-plug mechanical design of a compressed air connection with a valve, the entire leak test can be independently operated in a safe standard throughout the entire process, thereby avoiding human operating errors. The new operation method is simple and easy to implement, and can solve the problem of distortion of experimental data caused by leakage during the test due to damage to the seal due to excessively high or low pressure during the leak test. It can also solve the problem of consistency of leak test standards during the test verification when different after-treatment samples are replaced on the same vehicle and different test vehicles are replaced with each other, thereby ensuring good repeatability and consistency of the test verification data.

[0007] (II) Technical solution

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] A method for rapid pressure stabilization detection of vehicle aftertreatment sealing performance in a National VI vehicle emission test comprises the following steps:

[0010] Step 1: Vehicle Inspection

[0011] Before conducting a vehicle leak test, first conduct a vehicle inspection. The process is as follows:

[0012] S1. Check whether the vehicle's three-way catalytic converter and the engine cylinder exhaust are equipped with gaskets and the screws are tightened according to the torque;

[0013] S2. Check whether the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter accessories are coated with anti-sintering glue and tightened according to the torque requirements;

[0014] S3. Check whether a graphite gasket is installed between the GPF particle trap and the three-way catalytic converter, and whether the fastening screws are tightened according to the torque requirements;

[0015] S4. Check the graphite gasket installed between the GPF particle trap and the car muffler, and tighten the fastening screws according to the torque requirements;

[0016] S5. Check whether the GPF particle trap’s accessory differential pressure sensor pipes and joints are correctly installed;

[0017] S6. Check whether the connectors and accessories of each part of the car's muffler are installed correctly;

[0018] S7. Place the vehicle on a lifting platform and wait for post-processing sealing inspection.

[0019] Step 2: Equipment Installation

[0020] After inspecting the vehicle, the equipment is installed. The process is as follows:

[0021] S1. Lift the vehicle to a suitable height;

[0022] S2. Install the quick leak test mechanism with valve, connect it to the muffler of the vehicle to be tested, install the sealing gasket and quick connection clamp, and close the valve;

[0023] S3. Adjust the compressed air regulating valve to adjust the compressed air pipeline pressure to the appropriate pressure;

[0024] S4. Open the ball valve at the rear end of the quick-connect plug to allow the regulated compressed air to enter the entire sealed vehicle handling system;

[0025] S5. Observe whether the pressure gauge indication reaches the required range for post-processing test.

[0026] Step 3: Test operation

[0027] After the equipment is installed, the vehicle post-processing sealing is tested. The test process is as follows:

[0028] S1. Pass the pressure-regulated gas into the vehicle for post-processing to keep the pressure in the system constant;

[0029] S2. Spray the foam leak detection liquid on the exhaust of the three-way catalytic converter and the engine cylinder to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, replace the gasket and screws and reinstall.

[0030] S3. Spray the foam leak detection liquid on the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, apply sealant again and reinstall.

[0031] S4. Spray the foam leak detection liquid on the GPF differential pressure sensor and pipeline accessories to check the tightness. If leakage is found, bubbles will appear. Tighten the clamp according to the degree of leakage. Otherwise, replace the hose and reinstall it.

[0032] S5. Spray the foam leak detection liquid on the pipe connections of GPF, three-way catalytic converter and muffler to check the sealing;

[0033] S6. Check other test welding parts and parts where leakage may occur until the leakage is completely eliminated.

[0034] Preferably, after process S6 in step one, it is necessary to connect all electrical component plugs and fix the auxiliary support brackets to prevent vibration deformation and loosening.

[0035] Preferably, after process S3 in step 2, the female quick-plug connector of the pressure-regulated pipeline needs to be connected to the male quick-plug connector at the front end of the quick leak test clamp, so that the entire gas pipeline can be connected to the vehicle post-processing.

[0036] Preferably, if leakage is found in process S5 in step three, bubbles will appear and the screws are tightened according to the degree of leakage, otherwise the number of gaskets is increased and glue is applied and reinstalled.

[0037] Preferably, a National VI vehicle emission test vehicle after-treatment sealing stabilization pressure rapid detection system comprises a compressed air source, the output end of the compressed air source is connected to a plurality of gas cylinders, and the upper ends of the gas cylinders are respectively provided with pressure regulating valves and a first pressure indicator gauge, the output end of the gas cylinder is connected to an air hose, the rear end of the air hose is connected to a stainless steel quick plug, a valve is provided near the middle of the stainless steel quick plug, the rear end of the stainless steel quick plug is connected to a quick switching mechanism assembly, a stainless steel quick clamp is provided in the middle of the quick switching mechanism assembly, and the rear end of the quick switching mechanism assembly is connected to the vehicle after-treatment system.

[0038] Preferably, a second pressure indicator gauge is provided at the upper front end of the quick-change mechanism assembly.

[0039] Preferably, a sealing gasket is provided inside the stainless steel quick clamp.

[0040] Preferably, the vehicle after-treatment system includes structures such as a muffler, a DPF, and a three-way catalytic converter.

[0041] Working principle: The vehicle emission test vehicle after-treatment sealing stable pressure rapid detection method is designed to install a compressed air regulating valve with a pressure gauge indication at the outlet of the industrial compressed air. According to the requirements of different models for the after-treatment leak test pressure, the pipeline entering the vehicle after-treatment channel is adjusted. The valve in the middle of the pipeline controls the air circuit. The pipeline and the muffler part of the vehicle after-treatment are quickly connected with a stainless steel clamp with a sealing ring, and a pressure gauge is installed to monitor the compressed air pressure at the position of the car muffler. The pressure at this time is the actual pressure in the vehicle after-treatment system. After opening all valves, only one operator is required to spray the foam leak detection liquid on the three-way catalyst, GPF, muffler and other parts that are connected and may leak to check the leakage, so that one operator can perform standard inspection and test on the vehicle after-treatment. This detection method is simple, safe and easy to operate, with good repeatability and high data accuracy. The intake pressure can be adjusted according to the needs of different models for testing. It is suitable for vehicle emission verification, after-treatment cost reduction and development test verification stages.

[0042] (III) Beneficial effects

[0043] The present invention provides a method for rapid pressure stabilization detection of vehicle post-treatment sealing performance in the National VI vehicle emission test. It has the following beneficial effects:

[0044] 1. The present invention provides a method for rapid pressure-stabilized detection of vehicle post-processing sealing performance in a National VI vehicle emission test. The method limits the compressed air pressure and maintains a constant pressure test method, which meets the requirements of automobile post-processing sealing pressure, does not increase the test pressure, and avoids damage to parts. A quick connection device with a valve is used to connect to the vehicle muffler, which ensures the leak test sealing performance and eliminates human operating errors. One person can check the sealing performance of the vehicle post-processing. The method makes the sealing performance inspection simple and convenient, significantly improves the test accuracy, reduces labor intensity, and greatly improves work efficiency.

[0045] 2. The present invention provides a method for rapid pressure-stabilized detection of vehicle post-processing sealing performance in a National VI whole vehicle emission test. It is a necessary detection link before the whole vehicle emission test. Through the design of sealing detection modes and methods, it is applicable to different forms of National VI emission vehicle test post-processing inspection requirements. Only one operator is required to operate independently. The method is simple, convenient and feasible. The detection pressure is controllable and can be observed in real time. The sealing test effect of the post-processing system before and after the experiment is good, the data accuracy is high, the test pieces and seals are not damaged in accordance with the standards, data distortion caused by leakage before and during the post-processing test is avoided, the cost of repeated tests is avoided, the test efficiency is improved, and the test cost is reduced.

[0046] 3. The present invention provides a method for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test. The detection method is simple, safe, easy to operate, has good repeatability, and high data accuracy. The intake pressure can be adjusted according to the requirements of different vehicle models for testing. It is suitable for vehicle emission verification, post-processing cost reduction, and development test verification stages. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a schematic diagram of the composition of the post-processing sealing pressure stabilization rapid detection system of the present invention.

[0048] Among them, 1. pressure regulating valve; 2. first pressure indicator; 3. air hose; 4. stainless steel quick plug; 5. valve; 6. second pressure indicator; 7. quick transfer mechanism assembly; 8. stainless steel quick clamp; 9. sealing gasket; 10. vehicle after-treatment system; 11. compressed air source. DETAILED DESCRIPTION

[0049] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0050] Example:

[0051] like Figure 1 As shown, an embodiment of the present invention provides a method for rapid pressure stabilization detection of vehicle post-treatment sealing performance in a National VI vehicle emission test, comprising the following steps:

[0052] Step 1: Vehicle Inspection

[0053] Before conducting a vehicle leak test, first conduct a vehicle inspection. The process is as follows:

[0054] S1. Check whether the vehicle's three-way catalytic converter and the engine cylinder exhaust are equipped with gaskets and the screws are tightened according to the torque;

[0055] S2. Check whether the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter accessories are coated with anti-sintering glue and tightened according to the torque requirements;

[0056] S3. Check whether a graphite gasket is installed between the GPF particle trap and the three-way catalytic converter, and whether the fastening screws are tightened according to the torque requirements;

[0057] S4. Check the graphite gasket installed between the GPF particle trap and the car muffler, and tighten the fastening screws according to the torque requirements;

[0058] S5. Check whether the GPF particle trap’s accessory differential pressure sensor pipes and joints are correctly installed;

[0059] S6. Check whether the connectors and accessories of each part of the car's muffler are installed correctly;

[0060] S7. Connect all electrical component plugs and fix the auxiliary support brackets to prevent vibration deformation and loosening;

[0061] S8. Place the vehicle on a lifting platform and wait for post-processing sealing inspection.

[0062] Step 2: Equipment Installation

[0063] After inspecting the vehicle, the equipment is installed. The process is as follows:

[0064] S1. Lift the vehicle to a suitable height;

[0065] S2. Install the quick leak test mechanism with valve, connect it to the muffler of the vehicle to be tested, install the sealing gasket and quick connection clamp, and close the valve;

[0066] S3. Adjust the compressed air regulating valve to adjust the compressed air pipeline pressure to the appropriate pressure;

[0067] S4. Connect the female quick-plug connector of the pressure-regulated pipeline to the male quick-plug connector at the front end of the quick leak test clamp, so that the entire gas pipeline is connected to the vehicle post-processing;

[0068] S5. Open the ball valve at the rear end of the quick-connect plug to allow the regulated compressed air to enter the entire sealed vehicle handling system;

[0069] S6. Observe whether the pressure gauge indication reaches the required range for post-processing test.

[0070] Step 3: Test operation

[0071] After the equipment is installed, the vehicle post-processing sealing is tested. The test process is as follows:

[0072] S1. Pass the pressure-regulated gas into the vehicle for post-processing to keep the pressure in the system constant;

[0073] S2. Spray the foam leak detection liquid on the exhaust of the three-way catalytic converter and the engine cylinder to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, replace the gasket and screws and reinstall.

[0074] S3. Spray the foam leak detection liquid on the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, apply sealant again and reinstall.

[0075] S4. Spray the foam leak detection liquid on the GPF differential pressure sensor and pipeline accessories to check the tightness. If leakage is found, bubbles will appear. Tighten the clamp according to the degree of leakage. Otherwise, replace the hose and reinstall it.

[0076] S5. Spray the foam leak detection liquid on the GPF, three-way catalytic converter, muffler and other pipe connections to check the tightness. If leakage is found, bubbles will appear. Tighten the screws according to the degree of leakage. Otherwise, increase the number of gaskets and apply glue to reinstall;

[0077] S6. Check other test welding parts and parts where leakage may occur until the leakage is completely eliminated.

[0078] The country's six complete vehicle emission tests for vehicle after-treatment sealing stabilization rapid detection system includes a compressed air source 11, the output end of the compressed air source 11 is connected to a plurality of gas cylinders, and the upper ends of the gas cylinders are respectively provided with pressure regulating valves 1 and first pressure indicator gauges 2, the output end of the gas cylinder is connected to an air hose 3, the rear end of the air hose 3 is connected to a stainless steel quick plug 4, the stainless steel quick plug 4 is provided with a valve 5 in the middle, the rear end of the stainless steel quick plug 4 is connected to a quick switching mechanism assembly 7, the middle of the quick switching mechanism assembly 7 is provided with a stainless steel quick clamp 8, and the rear end of the quick switching mechanism assembly 7 is connected to a vehicle after-treatment system 10.

[0079] A second pressure indicator 6 is provided at the upper front end of the quick switching mechanism assembly 7, a sealing gasket 9 is provided inside the stainless steel quick clamp 8, and the vehicle post-processing system 10 includes a muffler, a DPF, a three-way catalytic converter and other structures.

[0080] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A method for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test, characterized in that: The following steps are involved: Step 1: Vehicle Inspection Before conducting a vehicle leak test, first conduct a vehicle inspection. The process is as follows: S1. Check whether the vehicle's three-way catalytic converter and the engine cylinder exhaust are equipped with gaskets and the screws are tightened according to the torque; S2. Check whether the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter accessories are coated with anti-sintering glue and tightened according to the torque requirements; S3. Check whether a graphite gasket is installed between the GPF particle trap and the three-way catalytic converter, and whether the fastening screws are tightened according to the torque requirements; S4. Check the graphite gasket installed between the GPF particle trap and the car muffler, and tighten the fastening screws according to the torque requirements; S5. Check whether the GPF particle trap’s accessory differential pressure sensor pipes and joints are correctly installed; S6. Check whether the connectors and accessories of each part of the car's muffler are installed correctly; S7. Place the vehicle on a lifting platform and wait for post-processing sealing inspection; Step 2: Equipment Installation After inspecting the vehicle, the equipment is installed. The process is as follows: S1. Lift the vehicle to a suitable height; S2. Install the quick leak test mechanism with valve, connect it to the muffler of the vehicle to be tested, install the sealing gasket and quick connection clamp, and close the valve; S3. Adjust the compressed air regulating valve to adjust the compressed air pipeline pressure to the appropriate pressure; S4. Open the ball valve at the rear end of the quick-connect plug to allow the regulated compressed air to enter the entire sealed vehicle handling system; S5. Observe whether the pressure gauge indication meets the post-processing test requirements; Step 3: Test operation After the equipment is installed, the vehicle post-processing sealing is tested. The test process is as follows: S1. Pass the pressure-regulated gas into the vehicle for post-processing to keep the pressure in the system constant; S2. Spray the foam leak detection liquid on the exhaust of the three-way catalytic converter and the engine cylinder to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, replace the gasket and screws and reinstall. S3. Spray the foam leak detection liquid on the front oxygen sensor and rear oxygen sensor of the three-way catalytic converter to check the sealing. If leakage is found, bubbles will appear. Tighten the threads according to the degree of leakage. Otherwise, apply sealant again and reinstall. S4. Spray the foam leak detection liquid on the GPF differential pressure sensor and pipeline accessories to check the tightness. If leakage is found, bubbles will appear. Tighten the clamp according to the degree of leakage. Otherwise, replace the hose and reinstall it. S5. Spray the foam leak detection liquid on the GPF, three-way catalytic converter and muffler pipe connection to check the sealing; S6. Check other test welding parts and parts where leakage may occur until the leakage is completely eliminated.

2. The method for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test according to claim 1 is characterized in that: After process S6 in step 1, it is necessary to connect all electrical component plugs and fix the auxiliary support brackets to prevent vibration deformation and loosening.

3. The method for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test according to claim 1 is characterized in that: After process S3 in step 2, it is necessary to connect the quick-plug female end of the pressure-regulated pipeline with the quick-plug male end at the front end of the quick leak test clamp, so that the entire gas pipeline can be connected to the vehicle post-processing.

4. The method for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test according to claim 1 is characterized in that: If leakage is found in the process S5 of step three, bubbles will appear and the screws should be tightened according to the degree of leakage. Otherwise, increase the number of gaskets and apply glue and reinstall.

5. A system for rapid pressure stabilization detection of vehicle post-processing sealing performance in the National VI vehicle emission test, used to implement the detection method described in any one of claims 1 to 4, characterized in that: The invention comprises a compressed air source (11), the output end of the compressed air source (11) is connected to a plurality of gas cylinders, and the upper ends of the gas cylinders are respectively provided with pressure regulating valves (1) and first pressure indicator gauges (2), the output end of the gas cylinder is connected to an air hose (3), the rear end of the air hose (3) is connected to a stainless steel quick plug (4), the middle part of the stainless steel quick plug (4) is provided with a valve (5), the rear end of the stainless steel quick plug (4) is connected to a quick switching mechanism assembly (7), the middle part of the quick switching mechanism assembly (7) is provided with a stainless steel quick clamp (8), and the rear end of the quick switching mechanism assembly (7) is connected to a vehicle post-processing system (10).

6. A National VI vehicle emission test vehicle post-processing sealing stabilization rapid detection system according to claim 5, characterized in that: A second pressure indicator gauge (6) is provided at the upper front end of the quick-change mechanism assembly (7).

7. The system for rapid pressure stabilization detection of vehicle post-processing sealing performance for the National VI vehicle emission test according to claim 5 is characterized in that: A sealing gasket (9) is arranged inside the stainless steel quick clamp (8).

8. The system for rapid pressure stabilization detection of vehicle post-processing sealing performance for the National VI vehicle emission test according to claim 5 is characterized in that: The vehicle aftertreatment system (10) comprises a muffler, a DPF, and a three-way catalytic converter structure.

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