Method for testing gasoline engine supercharger lubricating oil seals

Abstract

The application discloses a gasoline engine supercharger lubricating oil sealing test method, which comprises the following steps: step one, modifying the supercharger, and adding a pressure sensor at key positions of the supercharger; step two, operating the engine, and selecting the maximum risk working conditions of oil leakage of the pressure end and the vortex end of the supercharger respectively; step three, under the pressure end risk working condition, adjusting the air filter pressure drop to 1 times, 1.5 times and 2 times of the design requirement air filter pressure drop of the supercharger, respectively operating for 15 minutes, and observing whether the pressure end leaks oil after pressure; step four, under the vortex end risk working condition, operating for 4 hours, and checking whether the vortex shell and the turbine surface leak oil every hour. The application can quickly verify the sealing effect of the engine supercharger lubricating oil, can be used for verifying, evaluating, testing and the like in aspects of supercharger lubricating oil sealing design specification verification and reliability examination, and provides an effective test method for supercharger design development, CAE simulation verification and fault elimination, and has a good application prospect.

Description

Technical Field

[0001] This invention relates to a method for testing the sealing of lubricating oil in a gasoline engine turbocharger. Background Technology

[0002] The main structure of a gasoline engine turbocharger consists of components such as a turbine, impeller, thrust bearing, floating bearing, sealing ring, volute, and pressure shell. Under certain special operating conditions, when the internal pressure or pressure difference of the turbocharger's volute and pressure ends is large, sealing failure may occur, leading to the risk of lubricating oil leakage. If the turbocharger continues to operate with weakened or failed sealing and lubrication, it will ultimately result in turbocharger damage.

[0003] Given this hazard, in order to prevent turbocharger damage due to lubricating oil leakage, it is necessary to test the turbocharger lubricating oil sealing capability under certain special operating conditions. Summary of the Invention

[0004] The purpose of this invention is to provide a method for testing the lubricating oil seal of a gasoline engine turbocharger. This method can intuitively confirm whether the turbocharger seal meets the design specifications, providing valuable data and accumulating experience for turbocharger simulation design, manufacturing process, and material selection.

[0005] The objective of this invention is achieved through the following technical solution: A method for testing the lubricating oil seal of a gasoline engine turbocharger includes the following steps: Step 1: Modify the turbocharger by installing pressure sensors in key parts of the turbocharger; Step 2: Run the engine and select the operating conditions with the highest risk of oil leakage at the turbocharger pressure end and turbine end respectively; Step 3: Under the risky operating conditions at the pressure end, adjust the air filter pressure drop to 1, 1.5, and 2 times the air filter pressure drop required by the turbocharger design. After running for 15 minutes each time, observe whether there is oil leakage after the pressure end is pressed. Step 4: Under the risky operating conditions at the turbine end, run for 4 hours, stopping every hour to check for oil leaks inside the turbine housing and on the turbine surface.

[0006] Compared with the prior art, the present invention has the following advantages: This invention can quickly verify the sealing effect of engine turbocharger lubricating oil. It can be used for verification and evaluation tests of turbocharger lubricating oil sealing design specifications and reliability assessment. It provides an effective test method for turbocharger design and development, CAE simulation verification and fault diagnosis, and provides a new direction for scientific research and development. It has a good application prospect. Detailed Implementation

[0007] The technical solution of the present invention will be further described below, but it is not limited thereto. Any modifications or equivalent substitutions to the technical solution of the present invention that do not depart from the spirit and scope of the technical solution of the present invention should be covered within the protection scope of the present invention.

[0008] This invention provides a method for testing the sealing of lubricating oil in a gasoline engine turbocharger, comprising the following steps: 1. Preparatory work before the experiment: a) Modify the turbocharger and add 5 pressure sensors. The specific installation locations are as follows: the gas side of the pressure end piston ring, the oil side of the pressure end piston ring, the gas side of the scroll end piston ring, the oil side of the scroll end piston ring, and the oil return port.

[0009] b) Restore the modified turbocharger to the test engine and install the engine on the test bench, ensuring that the engine and test bench are working properly, that the engine has no water, oil or air leaks, and that it can start normally and smoothly.

[0010] c) The engine crankshaft ventilation duct is connected to the atmosphere or a recovery device.

[0011] d) Install a transparent tube in the pressurized pipeline.

[0012] e) Conduct tests using brand new air filters and air filter elements.

[0013] 2. Control of test conditions: Test conditions shall be controlled in accordance with Clause 6 of GB / T 18297-2001.

[0014] 3. Experimental Procedure: 3.1 Selection of Risk Point Operating Conditions a) Start the engine, check the engine idle speed stability, and after confirming that there are no abnormalities in the engine status, warm up the engine. The warm-up conditions are engine speed of 2500 r / min and load of 20%. b) Warm-up ends when the engine coolant and engine oil temperatures reach 90°C; c) After adjusting the engine to a stable idle speed, record the idle speed test data; d) Adjust the engine speed to 1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm and maximum speed. At each speed point, adjust the engine load to 10%, 25%, 50%, 70% and 100% and record the test data. e) Based on the above test data, conduct risk point analysis: select several operating conditions with smaller and larger pressure differences between the gas side and right side of the piston ring at the pressure end as pressure end risk conditions; select several operating conditions with smaller and larger pressure differences between the gas side and right side of the piston ring at the scroll end as scroll end risk conditions; and select the engine rated speed full load condition and the maximum speed low load condition as scroll end and pressure end risk conditions.

[0015] 3.2 Turbocharger pressure end lubricating oil sealing test 3.2.1 Engine air filter pressure drop under full speed and full load conditions (1 time) a) After the engine is warmed up, adjust the engine to the idle speed risk point condition, run it for 15 minutes, stop the engine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. b) After the engine is warmed up, adjust the engine to a certain pressure end risk condition, run it for 15 minutes, stop the engine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. c) After the engine is warmed up, run other high-risk operating conditions at the pressure end for 15 minutes each. Stop the machine for each operating condition and observe the transparent pipeline for any signs of oil leakage and take photos to record them. d) After the engine is warmed up, adjust the engine to the highest speed and low load condition, run it for 15 minutes, stop the machine and observe whether there are any oil leaks in the transparent pipeline and take pictures to record the results; e) After the engine is warmed up, adjust the engine to the rated speed and full load condition, run for 15 minutes, stop the machine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. f) Remove the pipe after the vortex and observe whether there is any oil leakage at the vortex end.

[0016] 3.2.2 Engine air filter pressure drop under full speed and full load conditions (1.5 times) a) Adjust the air filter pressure drop and appropriately block the air filter inlet to increase the pressure drop by 1.5 times under full speed and full load conditions; b) Repeat steps a) to f) under state 3.2.1.

[0017] 3.2.3 Engine air filter pressure drop under full speed and full load conditions (2 times) a) Adjust the air filter pressure drop and appropriately block the air filter inlet to increase the pressure drop by 2 times under full speed and full load conditions; b) Repeat steps a) to f) under state 3.2.1.

[0018] 3.3 Turbocharger vortex end lubricating oil sealing test a) The test was conducted using a brand new air filter with the air filter pressure drop at its original state; b) After the engine is warmed up, adjust the engine to the turbine end risk condition and run it for 4 hours. Stop the engine every 1 hour, remove the turbine end pipeline, observe whether there are any oil leaks inside the turbine housing and on the surface of the turbine housing, and take photos to record. c) For each vortex end risk condition, the machine must be run for 4 hours to observe whether there is oil leakage at the vortex end and take photos for record.

[0019] 4. Precautions: a) Operate the engine strictly according to the above operating conditions; b) During the process of modifying the turbocharger and installing a pressure sensor, avoid damaging the turbocharger and causing oil or air leaks; c) When modifying the air filter pressure drop, prevent the blockage object from being sucked into the air filter or engine; d) Each risk condition must be verified separately to avoid being unable to identify the problem after a failure occurs; e) Before each risk point operation verification, the engine must be in a warm-up state.

[0020] 5. Data recording and analysis: a) During the risk point operating condition selection test, the test data recording should include, but is not limited to, the following parameters: engine speed, engine torque, coolant inlet and outlet temperature, coolant inlet pressure, engine oil temperature, engine oil pressure, turbine inlet and outlet temperature, turbine inlet and outlet pressure, intake manifold temperature and pressure, air filter temperature and pressure drop, and pressure at 5 measuring points on the turbocharger.

[0021] b) Based on the test data, select the risky operating conditions (see Table 1) and conduct sealing tests.

[0022] Table 1. Selection of Operating Conditions for Risk Points in Turbocharger Lubricating Oil Sealing Test

Claims

1. A method for testing the sealing of lubricating oil in a gasoline engine turbocharger, characterized in that... The method includes the following steps: Step 1: Modify the turbocharger by installing pressure sensors at key locations on the turbocharger and adding transparent tubing to the turbocharger's post-pressurization pipeline. The specific installation locations of the pressure sensors are as follows: gas side of the pressure end piston ring, oil side of the pressure end piston ring, gas side of the scroll end piston ring, oil side of the scroll end piston ring, and oil return port. Step 2: Run the engine and select the operating conditions with the highest risk of oil leakage at the turbocharger pressure end and turbine end, respectively. The method for selecting the risk operating conditions is as follows: a) Start the engine, check the engine idle speed stability, and after confirming that there are no abnormalities in the engine status, warm up the engine. The warm-up conditions are engine speed of 2500 r / min and load of 20%. b) Warm-up ends when the engine coolant and engine oil temperatures reach 90°C; c) After adjusting the engine to a stable idle speed, record the idle speed test data; d) Adjust the engine speed to 1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm, 5000 rpm and maximum speed. At each speed point, adjust the engine load to 10%, 25%, 50%, 70% and 100% and record the test data. e) Based on the above test data, conduct risk point analysis: select several operating conditions with smaller and larger pressure differences between the gas side and oil side of the piston ring at the pressure end as pressure end risk conditions; select several operating conditions with smaller and larger pressure differences between the gas side and oil side of the piston ring at the scroll end as scroll end risk conditions; and select the engine rated speed full load condition and the maximum speed low load condition as scroll end and pressure end risk conditions. Step 3: Turbocharger pressure end lubricating oil sealing test: Under the risky operating conditions at the pressure end, adjust the air filter pressure drop to 1, 1.5, and 2 times the air filter pressure drop required by the turbocharger design, run for 15 minutes each time, and then observe whether there is oil leakage after the pressure end is pressed. Step 4: Turbocharger turbine end lubricating oil sealing test: Under the risky operating conditions at the turbine end, run for 4 hours, and stop every hour to check for oil leakage inside the turbine housing and on the turbine surface.

2. The method for testing the sealing of gasoline engine turbocharger lubricating oil according to claim 1, characterized in that... In step two, during the risk point operating condition selection test, the test data recording includes the following parameters: engine speed, engine torque, coolant inlet and outlet temperatures, coolant inlet pressure, engine oil temperature, engine oil pressure, turbine inlet and outlet temperatures, turbine inlet and outlet pressures, intake manifold temperature and pressure, air filter temperature and pressure drop, and turbocharger measuring point pressure.

3. The method for testing the sealing of gasoline engine turbocharger lubricating oil according to claim 1, characterized in that... In step three, the specific steps for the turbocharger pressure end lubricating oil sealing test are as follows: Step 3:

1. Engine operating at full speed and full load with a 1 / 2 pressure drop in the fresh air filter. a) After the engine is warmed up, adjust the engine to the idle speed risk point condition, run it for 15 minutes, stop the engine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. b) After the engine is warmed up, adjust the engine to a certain pressure end risk condition, run it for 15 minutes, stop the engine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. c) After the engine is warmed up, run other pressure end risk conditions for 15 minutes each. Stop the machine for each condition and observe the transparent pipeline for any oil leakage and take photos. d) After the engine is warmed up, adjust the engine to the highest speed and low load condition, run for 15 minutes, stop the machine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them; e) After the engine is warmed up, adjust the engine to the rated speed and full load condition, run for 15 minutes, stop the engine and observe whether there are any oil leaks in the transparent pipeline and take photos to record them. f) Remove the pipe after the vortex and check for oil leakage at the vortex end; Step 3.2: When the engine operates at full speed and full load, the fresh air filter pressure drops by 1.5 times. a) Adjust the air filter pressure drop and appropriately block the air filter inlet to increase the pressure drop by 1.5 times under full speed and full load conditions; b) Repeat steps a) through f) of step 31. Step 3: When the engine operates at full speed and full load, the fresh air filter pressure drops by 2 times. a) Adjust the air filter pressure drop and appropriately block the air filter inlet to increase the pressure drop by 2 times under full speed and full load conditions; b) Repeat steps a) through f) of step 3.

1.

4. The method for testing the sealing of gasoline engine turbocharger lubricating oil according to claim 1, characterized in that... In step four, the specific steps for the turbocharger turbine end lubricating oil sealing test are as follows: a) Conduct a turbocharger turbine end lubricating oil sealing test using a brand new air filter, with the air filter pressure drop returned to its original state; b) After the engine is warmed up, adjust the engine to the turbine end risk condition and run it for 4 hours. Stop the engine every 1 hour, remove the turbine post-turbine pipeline, observe the turbine housing and turbine surface for any oil leaks and take photos to record them. c) For each vortex end risk condition, the machine must be run for 4 hours to observe whether there is oil leakage at the vortex end and take photos for record.

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