Test system for integrated differential pressure regulating valve of aero-engine lubricating oil pump set

Abstract

According to the test system for the integrated differential pressure regulating valve of the lubricating oil pump set of the aero-engine, parts such as a lubricating oil filter are arranged behind a booster stage of the lubricating oil pump set, and measuring points for sensing oil supply pressure of the differential pressure regulating valve are arranged behind the parts such as the lubricating oil filter and are consistent with the measuring positions of the oil supply pressure of the aero-engine; the performance test error caused by arranging the oil supply pressure at the booster stage can be avoided; flowmeters are respectively arranged at an inlet and an outlet of a booster stage of the lubricating oil pump set, and actual oil supply flow and overflow flow characteristics can be analyzed through the flow of the inlet and the outlet; the valve opening degrees corresponding to a booster stage outlet and a total oil return outlet can be adjusted to adjust outlet pressure, the gas path pressure is adjusted by adjusting the opening degree of a valve on a gas path, the change process from slow running to middle of an aero-engine is simulated through rotating speed abrupt change adjustment of a lubricating oil pump set, and different pressure combination working conditions and the change process of a rotating speed transition state are studied. The action of the differential pressure regulating valve influences the changes of oil supply pressure, flow and the like.

Description

Technical Field

[0001] This application belongs to the field of test technology for integrated differential pressure regulating valves in aero-engine lubricating oil pump units, specifically relating to a test system for integrated differential pressure regulating valves in aero-engine lubricating oil pump units. Background Technology

[0002] The lubricating oil pump set for aero-engines is mainly used for the delivery and recovery of lubricating oil in the bearings and transmission gears of aero-engines. The performance and life tests of traditional lubricating oil pump sets are conducted using pure oil. In recent years, it has been possible to carry out performance test research on lubricating oil pump sets under imported oil and gas conditions. However, the test research on lubricating oil pump sets with integrated differential pressure valves is insufficient. There is a lack of performance test research on problems such as abnormal fluctuations in lubricating oil pressure that frequently occur in aero-engines, especially the performance test research on the transition state changes of aero-engines. This makes it impossible to support the troubleshooting of abnormal lubricating oil pressure in aero-engines.

[0003] Currently, the performance testing method for the integrated differential pressure valve of the lubricating oil pump set of aero-engines is flawed because the difference between the position of the differential pressure valve sensing the oil supply pressure and the actual situation of the aero-engine causes a difference in the outlet pressure of the booster stage of the lubricating oil pump set, which in turn affects the actual oil supply flow and overflow flow. Therefore, the test results based on this method cannot reflect the actual performance of the lubricating oil pump set.

[0004] This application is made in view of the aforementioned technical deficiencies. Summary of the Invention

[0005] The purpose of this application is to provide a test system for integrating a differential pressure regulating valve into an aircraft engine lubricating oil pump assembly, so as to overcome or mitigate at least one of the known technical defects.

[0006] The technical solution of this application is:

[0007] A test system for an integrated differential pressure regulating valve in an aircraft engine lubricating oil pump assembly includes an oil supply main pipe, an oil return main pipe, an oil circuit for the differential pressure regulating valve, and an air circuit for the differential pressure regulating valve.

[0008] The lubricating oil pump group for aircraft engines is divided into five stages. The outlets of the first four stages are combined into the total return oil outlet, and the fifth stage is the booster stage.

[0009] The differential pressure regulating valve is integrated into the lubricating oil pump unit and has both oil pressure connector and air pressure connector.

[0010] The main oil supply pipe inlet connects to the heated lubricating oil tank, and the outlet is divided into five branches, which are respectively connected to the five-stage inlet of the lubricating oil pump group;

[0011] On the five branch lines at the outlet of the main oil supply pipeline, the first flow meter Q1, the second flow meter Q2, the third flow meter Q3, the fourth flow meter Q4, and the fifth flow meter Q5 are respectively installed at the five-stage inlet;

[0012] The return oil main inlet is divided into two branches, which are respectively connected to the main return oil outlet and the booster stage outlet of the lubricating oil pump group, and the outlet is connected to the heated lubricating oil tank.

[0013] On the branch line connecting the inlet of the main return oil pipe to the main return oil outlet, the sixth pressure gauge P6 and the first electric regulating valve K1 are installed in sequence.

[0014] On the branch line connecting the inlet of the return oil main to the outlet of the booster stage, the seventh pressure gauge P7, the lubricating oil filter F, the tenth electric regulating valve K10, the tenth pressure gauge P10, the sixth flow meter Q6, and the second electric regulating valve K2 are installed in sequence.

[0015] The oil circuit inlet of the differential pressure valve is connected to the oil pressure connector of the differential pressure valve, and the outlet is connected to the branch line of the return oil main pipe inlet connected to the outlet of the booster stage. It is located between the tenth electric regulating valve K10 and the tenth pressure gauge P10.

[0016] The outlet of the differential pressure valve is connected to the pneumatic connector of the differential pressure valve, and the inlet is connected to the high-pressure gas source. The fifth electric regulating valve K5 and the ninth pressure gauge P9 are installed on it in sequence.

[0017] When the difference between the measured values ​​of the tenth pressure gauge P10 and the ninth pressure gauge P9 is greater than the differential pressure setting value, the overflow port inside the differential pressure regulating valve opens, allowing some of the lubricating oil at the outlet of the booster stage of the lubricating oil pump unit to overflow to the main return oil outlet.

[0018] According to at least one embodiment of this application, in the above-mentioned test system for integrating a differential pressure valve into an aircraft engine lubricating oil pump assembly, a first thermometer T1 is installed on the oil supply main pipe;

[0019] On the five branches at the outlet of the main oil supply pipe, pressure gauges P1, P2, P3, P4, and P5 are respectively installed to measure the lubricating oil pressure entering the five-stage lubricating oil pump group.

[0020] The first pressure gauge P1, the second pressure gauge P2, the third pressure gauge P3, the fourth pressure gauge P4, and the fifth pressure gauge P5 are located downstream of the first flow meter Q1, the second flow meter Q2, the third flow meter Q3, the fourth flow meter Q4, and the fifth flow meter Q5.

[0021] According to at least one embodiment of this application, in the above-described test system for integrating an aero-engine lubricating oil pump assembly with a differential pressure regulating valve, the lubricating oil pump assembly is driven by a first variable frequency motor M1.

[0022] According to at least one embodiment of this application, the above-mentioned test system for integrating a differential pressure valve with an aero-engine lubricating oil pump group further includes an oil mixing pipeline, an air supply pipeline, and a mixing pipeline.

[0023] The oil mixing pipeline is connected to a heated lubricating oil tank at the inlet and to an oil-gas mixing tank at the outlet. It is equipped with an oil supply pump B and a seventh flow meter Q7 in sequence.

[0024] The gas supply pipeline is connected to a high-pressure gas source at the inlet and to an oil-gas mixing tank at the outlet. The fourth electric regulating valve K4 and the eighth flow meter Q8 are installed on it in sequence.

[0025] The mixing pipeline inlet connects to the oil-gas mixing box, and the outlet is divided into four branches, which are connected to the branch of the oil supply main outlet connected to the inlet of the first four stages of the lubricating oil pump group through the sixth electric three-way switching valve K6, the seventh electric three-way switching valve K7, the eighth electric three-way switching valve K8, and the ninth electric three-way switching valve K9, respectively.

[0026] According to at least one embodiment of this application, in the above-described test system for integrating an air engine lubricating oil pump assembly with a differential pressure regulating valve, the oil supply pump B is driven by a second variable frequency motor M2.

[0027] According to at least one embodiment of this application, the above-described test system for integrating a differential pressure regulating valve with an aero-engine lubricating oil pump assembly further includes a return branch.

[0028] The inlet of the return branch is connected to the oil mixing pipeline, located between the oil supply pump B and the seventh flow meter Q7, and the outlet is connected to the heated lubricating oil tank, on which the third electric regulating valve K3 is installed.

[0029] This application has at least the following beneficial technical effects:

[0030] A test system integrating a differential pressure regulating valve into an aircraft engine lubricating oil pump assembly is provided.

[0031] By installing components such as a lubricating oil filter after the booster stage of the lubricating oil pump group, and placing the measuring point for sensing the oil supply pressure of the differential pressure valve after the lubricating oil filter and other components, which is consistent with the oil supply pressure measurement position of the aero-engine, the performance test error caused by placing the oil supply pressure after the booster stage can be avoided.

[0032] Flow meters are installed at the inlet and outlet of the booster stage of the lubricating oil pump set, respectively. The actual oil supply flow and overflow flow characteristics can be analyzed by analyzing the inlet and outlet flow.

[0033] The outlet pressure can be adjusted by separately adjusting the valve openings corresponding to the booster stage outlet and the total return oil outlet, and the gas pressure can be adjusted by adjusting the valve openings on the gas line. By adjusting the sudden change in the speed of the lubricating oil pump group, the change process from idle to intermediate speed of an aero engine can be simulated. The influence of the differential pressure valve action on the changes in oil supply pressure and flow rate during different pressure combination conditions and speed transition states can be studied. Attached Figure Description

[0034] Figure 1This is a schematic diagram of a test system for integrating a differential pressure regulating valve into an aircraft engine lubricating oil pump assembly, as provided in an embodiment of this application.

[0035] To better illustrate this embodiment, some content in the accompanying drawings may be omitted, enlarged, or reduced. They are for illustrative purposes only and should not be construed as limiting the scope of this application. Detailed Implementation

[0036] To make the technical solution and advantages of this application clearer, the technical solution of this application will be described in a clearer and more complete manner below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only some embodiments of this application, and are only used to explain this application, not to limit this application. It should be noted that, for ease of description, only the parts related to this application are shown in the accompanying drawings, and other related parts can be referred to the general design.

[0037] Furthermore, unless otherwise defined, the technical or scientific terms used in this application description shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The word "comprising" as used in this application description indicates that the concept preceding the word encompasses the concepts listed following the word and their equivalents, without excluding other related concepts.

[0038] Furthermore, the terms indicating location used in the description of this application are only used to indicate relative directions or positional relationships. When the absolute position of the described object changes, its relative positional relationship may also change accordingly. It should also be noted that, unless otherwise explicitly specified and limited, terms such as "installation" and "connection" used in the description of this application should be interpreted broadly. For example, a connection can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand its specific meaning in this application according to the specific circumstances.

[0039] Aircraft engine lubricating oil pump sets are typically divided into five stages. The first four stages are supplied with lubricating oil through parallel pipelines, and the fifth stage is the booster stage. The outlets of the first four stages are combined into the total return oil outlet, and the outlet of the fifth stage is the booster stage outlet.

[0040] The differential pressure valve is a mechanical valve integrated on the lubricating oil pump unit. It has an oil pressure connector and an air pressure connector, which respectively sense the oil supply pressure and the bearing cavity pressure. When the pressure difference between the oil supply pressure and the bearing cavity pressure is greater than a certain pressure value, the pressure difference drives the internal slide valve, spring and other parts to move, so that the internal overflow port opens and the lubricating oil in the booster stage outlet of the lubricating oil pump unit overflows to the main return oil outlet.

[0041] Based on the above, this application provides a test system for integrating a differential pressure regulating valve into an aircraft engine lubricating oil pump assembly, such as... Figure 1As shown, it includes the main oil supply pipe, the main oil return pipe, the oil circuit of the differential pressure valve, the gas circuit of the differential pressure valve, the oil mixing pipeline, the return branch, the gas supply pipeline, and the mixing pipeline.

[0042] The main oil supply pipe inlet connects to the heated lubricating oil tank, and the outlet is divided into five branches, which are respectively connected to the five-stage inlet of the lubricating oil pump group.

[0043] The lubricating oil is stored in the heated lubricating oil tank, which can heat the lubricating oil to meet the test requirements.

[0044] A first thermometer T1 is installed on the oil supply main pipe to measure the temperature of the lubricating oil entering the oil supply main pipe from the heated lubricating oil tank.

[0045] On the five branches at the outlet of the main oil supply pipe, a first flow meter Q1, a second flow meter Q2, a third flow meter Q3, a fourth flow meter Q4, and a fifth flow meter Q5 are respectively installed at the five-stage inlet to measure the amount of lubricating oil entering the five-stage lubricating oil pump group.

[0046] On the five branches at the outlet of the main oil supply pipe, pressure gauges P1, P2, P3, P4, and P5 are respectively installed to measure the lubricating oil pressure entering the five-stage lubricating oil pump group.

[0047] The first pressure gauge P1, the second pressure gauge P2, the third pressure gauge P3, the fourth pressure gauge P4, and the fifth pressure gauge P5 are located downstream of the first flow meter Q1, the second flow meter Q2, the third flow meter Q3, the fourth flow meter Q4, and the fifth flow meter Q5.

[0048] The lubricating oil pump unit is driven by the first variable frequency motor M1. During the test, the speed change characteristics of the aircraft engine can be simulated by adjusting the speed of the first variable frequency motor M1, such as the speed change from idle to intermediate state. The time of the speed change process is set according to the required value, and the lubricating oil pump unit is driven to draw lubricating oil from the heated lubricating oil tank.

[0049] The return oil main inlet is divided into two branches, which are respectively connected to the main return oil outlet of the lubricating oil pump group and the booster stage outlet. The outlet is connected to the heated lubricating oil tank, so that the lubricating oil entering the lubricating oil pump group flows back to the heated lubricating oil tank.

[0050] On the branch line connecting the inlet of the return oil main to the main return oil outlet, a sixth pressure gauge P6 and a first electric regulating valve K1 are installed in sequence. During the test, the flow resistance of the pipeline, throttle, nozzle and other parts after the measuring point of the sixth pressure gauge P6 can be simulated by the opening of the first electric regulating valve K1, so as to adjust the pressure at the measuring point of the sixth pressure gauge P6, that is, at the main return oil outlet of the aero-engine lubricating oil pump group.

[0051] On the branch line connecting the inlet of the return oil main to the outlet of the booster stage, the seventh pressure gauge P7, the lubricating oil filter F, the tenth electric regulating valve K10, the sixth flow meter Q6, and the second electric regulating valve K2 are installed in sequence.

[0052] The combination of oil filter F and tenth electric regulating valve K10 can simulate the flow resistance of components such as oil filter and fuel oil radiator on the oil supply line after the booster stage of the aero-engine oil pump set. The tenth pressure gauge P10 is set downstream of the tenth electric regulating valve K10, which is equivalent to the position after the fuel oil radiator on the outlet line of the booster stage of the aero-engine oil pump set, and is consistent with the position of the oil supply pressure measuring point of the aero-engine.

[0053] During the test, the flow resistance of the pipeline, throttle, nozzle and other parts after the oil supply pressure measuring point of the booster stage of the aero-engine lubricating oil pump group can be simulated by adjusting the opening of the second electric regulating valve K2. This allows for the adjustment of the pressure at the measuring point P10 of the tenth pressure gauge. In addition, the pressure at the measuring point P7 of the seventh pressure gauge, i.e. the outlet of the booster stage of the aero-engine lubricating oil pump group, can be adjusted by adjusting the throttling effect of the lubricating oil filter F and the opening of the tenth electric regulating valve K10.

[0054] The sixth flow meter, Q6, is used to measure the oil supply flow rate of the booster stage of the lubricating oil pump assembly in aero engines.

[0055] The oil inlet of the differential pressure regulating valve is connected to the oil pressure connector of the differential pressure regulating valve, and the outlet is connected to the branch line of the return oil main pipe inlet connected to the booster stage outlet. It is located between the tenth electric regulating valve K10 and the tenth pressure gauge P10, and is in the same docking position as the fuel supply line pressure of the aero-engine, which makes the working characteristics of the differential pressure regulating valve closer to the actual situation of the aero-engine.

[0056] The outlet of the differential pressure valve is connected to the pneumatic connector of the differential pressure valve, and the inlet is connected to the high-pressure gas source. The fifth electric regulating valve K5 and the ninth pressure gauge P9 are installed on it in sequence.

[0057] During the test, the pressure at the measuring point P9 of the ninth pressure gauge can be adjusted by changing the opening of the fifth electric regulating valve K5 to simulate the pressure in the bearing cavity of an aero-engine.

[0058] When the difference between the measured values ​​of the tenth pressure gauge P10 and the ninth pressure gauge P9 is greater than the differential pressure setting value, the overflow port inside the differential pressure regulating valve opens, allowing a portion of the lubricating oil at the outlet of the booster stage of the lubricating oil pump unit to overflow to the main return oil outlet. The overflow flow rate is calculated by the difference between the measured values ​​of the fifth flow meter Q5 and the sixth flow meter Q6.

[0059] The inlet of the oil mixing pipeline is connected to the heated lubricating oil tank, and the outlet is connected to the oil-gas mixing tank. The oil supply pump B and the seventh flow meter Q7 are installed on it in sequence. The oil supply pump B is driven by the second variable frequency motor M2. After pressurizing the lubricating oil in the heated lubricating oil tank, it is sent to the oil-gas mixing tank. The seventh flow meter Q7 is used to measure the amount of lubricating oil sent from the heated lubricating oil tank to the oil-gas mixing tank. It can be adjusted by the speed of the second variable frequency motor M2.

[0060] The inlet of the return branch is connected to the oil mixing pipeline, located between the oil supply pump B and the seventh flow meter Q7. The outlet is connected to the heated lubricating oil tank, which is used to partially return the lubricating oil in the oil mixing pipeline. A third electric regulating valve K3 is installed on it, and the amount of lubricating oil sent from the heated lubricating oil tank to the oil-gas mixing tank can be adjusted by adjusting the opening of the third electric regulating valve K3.

[0061] The gas supply pipeline is connected to a high-pressure gas source at the inlet and to an oil-gas mixing tank at the outlet. It is used to supply high-pressure gas to the oil-gas mixing tank and mix it with lubricating oil to form an oil-gas mixture. A fourth electric regulating valve K4 and an eighth flow meter Q8 are installed on it in sequence. The amount of high-pressure gas supplied to the oil-gas mixing tank can be adjusted by adjusting the opening of the fourth electric regulating valve K4, thereby controlling the oil-gas ratio of the oil-gas mixture.

[0062] The mixing pipeline inlet connects to the oil-gas mixing box, and the outlet is divided into four branches, which are connected to the branch of the oil supply main outlet connected to the inlet of the first four stages of the lubricating oil pump group through the sixth electric three-way switching valve K6, the seventh electric three-way switching valve K7, the eighth electric three-way switching valve K8, and the ninth electric three-way switching valve K9, respectively.

[0063] During the test, the oil-air ratio and pressure of the lubricating oil entering the first four stages of the lubricating oil pump group can be adjusted by adjusting the opening of the sixth electric three-way switching valve K6, the seventh electric three-way switching valve K7, the eighth electric three-way switching valve K8, and the ninth electric three-way switching valve K9, so as to conduct a performance test of the lubricating oil pump group under two-phase conditions.

[0064] Based on the test system for the integrated differential pressure regulating valve of the aero-engine lubricating oil pump group disclosed in the above embodiments, it is necessary to study whether abnormal phenomena such as oil supply pressure fluctuations and abnormal flow rate decreases occur, so as to support the troubleshooting of aero-engine lubricating oil differential pressure problems. The following tests can be conducted as a reference:

[0065] After adjusting the inlet and outlet pressures of the lubricating oil pump group and the air circuit pressure of the differential pressure valve to the required levels, the speed change characteristics of the aero-engine are simulated by adjusting the speed change of the first variable frequency motor M1. During the speed change process, the pressure at the outlet of the aero-engine lubricating oil pump group booster stage (pressure at the seventh pressure gauge P7), the pressure at the aero-engine oil supply pressure measuring point (pressure at the tenth pressure gauge P10), the inlet flow rate of the aero-engine lubricating oil pump group booster stage (measured value of the fifth flow meter Q5), and the oil supply flow rate of the aero-engine lubricating oil pump group booster stage (measured value of the sixth flow meter Q6) are monitored. The change characteristics of the overflow flow rate are calculated, and the test results support the troubleshooting of aero-engine lubricating oil differential pressure problems.

[0066] The technical solution of this application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. Those skilled in the art should understand that the scope of protection of this application is obviously not limited to these specific embodiments. Without departing from the principles of this application, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of this application.

Claims

1. A test system for integrating a differential pressure regulating valve into an aircraft engine lubricating oil pump assembly, characterized in that, This includes the main oil supply line, the main oil return line, the differential pressure valve oil circuit, and the differential pressure valve air circuit; The lubricating oil pump group for aircraft engines is divided into five stages. The outlets of the first four stages are combined into the total return oil outlet, and the fifth stage is the booster stage. The differential pressure regulating valve is integrated into the lubricating oil pump unit and has both oil pressure connector and air pressure connector. The main oil supply pipe inlet connects to the heated lubricating oil tank, and the outlet is divided into five branches, which are respectively connected to the five-stage inlet of the lubricating oil pump group; On the five branch lines at the outlet of the main oil supply pipeline, the first flow meter Q1, the second flow meter Q2, the third flow meter Q3, the fourth flow meter Q4, and the fifth flow meter Q5 are respectively installed at the five-stage inlet; The return oil main inlet is divided into two branches, which are respectively connected to the main return oil outlet and the booster stage outlet of the lubricating oil pump group, and the outlet is connected to the heated lubricating oil tank. On the branch line connecting the inlet of the main return oil pipe to the main return oil outlet, the sixth pressure gauge P6 and the first electric regulating valve K1 are installed in sequence. On the branch line connecting the inlet of the return oil main to the outlet of the booster stage, the seventh pressure gauge P7, the lubricating oil filter F, the tenth electric regulating valve K10, the tenth pressure gauge P10, the sixth flow meter Q6, and the second electric regulating valve K2 are installed in sequence. The oil circuit inlet of the differential pressure valve is connected to the oil pressure connector of the differential pressure valve, and the outlet is connected to the branch line of the return oil main pipe inlet connected to the outlet of the booster stage. It is located between the tenth electric regulating valve K10 and the tenth pressure gauge P10. The outlet of the differential pressure valve is connected to the pneumatic connector of the differential pressure valve, and the inlet is connected to the high-pressure gas source. The fifth electric regulating valve K5 and the ninth pressure gauge P9 are installed on it in sequence. When the difference between the measured values ​​of the tenth pressure gauge P10 and the ninth pressure gauge P9 is greater than the differential pressure setting value, the overflow port inside the differential pressure regulating valve opens, allowing some of the lubricating oil at the outlet of the booster stage of the lubricating oil pump unit to overflow to the main return oil outlet.

2. The test system for integrating a differential pressure regulating valve into an aero-engine lubricating oil pump assembly according to claim 1, characterized in that, A first thermometer T1 is installed on the main oil supply pipe; On the five branches at the outlet of the main oil supply pipe, pressure gauges P1, P2, P3, P4, and P5 are respectively installed to measure the lubricating oil pressure entering the five-stage lubricating oil pump group. The first pressure gauge P1, the second pressure gauge P2, the third pressure gauge P3, the fourth pressure gauge P4, and the fifth pressure gauge P5 are located downstream of the first flow meter Q1, the second flow meter Q2, the third flow meter Q3, the fourth flow meter Q4, and the fifth flow meter Q5.

3. The test system for integrating a differential pressure regulating valve into an aero-engine lubricating oil pump assembly according to claim 2, characterized in that, The lubricating oil pump unit is driven by the first variable frequency motor M1.

4. The test system for integrating a differential pressure regulating valve into an aero-engine lubricating oil pump assembly according to claim 3, characterized in that, It also includes oil mixing pipelines, gas supply pipelines, and mixing pipelines; The oil mixing pipeline is connected to a heated lubricating oil tank at the inlet and to an oil-gas mixing tank at the outlet. It is equipped with an oil supply pump B and a seventh flow meter Q7 in sequence. The gas supply pipeline is connected to a high-pressure gas source at the inlet and to an oil-gas mixing tank at the outlet. The fourth electric regulating valve K4 and the eighth flow meter Q8 are installed on it in sequence. The mixing pipeline inlet connects to the oil-gas mixing box, and the outlet is divided into four branches, which are connected to the branch of the oil supply main outlet connected to the inlet of the first four stages of the lubricating oil pump group through the sixth electric three-way switching valve K6, the seventh electric three-way switching valve K7, the eighth electric three-way switching valve K8, and the ninth electric three-way switching valve K9, respectively.

5. The test system for integrating a differential pressure regulating valve into an aero-engine lubricating oil pump assembly according to claim 4, characterized in that, Oil pump B is driven by the second variable frequency motor M2.

6. The test system for integrating a differential pressure regulating valve into an aero-engine lubricating oil pump assembly according to claim 5, characterized in that, It also includes return branches; The inlet of the return branch is connected to the oil mixing pipeline, located between the oil supply pump B and the seventh flow meter Q7, and the outlet is connected to the heated lubricating oil tank, on which the third electric regulating valve K3 is installed.

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