System and method for measuring radial liquid flow force of slide valve

Abstract

The invention relates to a slide valve radial liquid flow force measuring system and method, the measuring system comprises a hydraulic energy source, a force sensor with a push rod, a displacement sensor, a valve core extension rod, a processor and the like, and the push rod on the force sensor can adjust the radial offset of a valve core in a cavity; the radial displacement of the valve element is collected through the displacement sensor, and the position of the valve element in the cavity in the measuring process can be judged; the radial resultant force and the resultant moment borne by the valve element at the moment can be obtained through data collected by the force sensor at any moment in the state that the valve element is separated from the cavity, and the problem that the radial liquid flow force of the sliding valve with the micron-order tiny radial clearance is difficult to measure is solved.

Description

Technical Field

[0001] The present invention relates to a radial fluid flow force measurement system and a test method for a sliding valve, and in particular to a radial fluid flow force measurement system and a test method for a servo valve under power level valve core static pressure and working flow, and belongs to the technical field of hydraulic and fluid transmission. Background Art

[0002] Electro-hydraulic servo valves are widely used in hydraulic servo systems. The fluid force on the valve core affects the movement performance of the valve core and is an important factor that needs to be strictly controlled in the design and manufacture of servo valves. At present, the performance characteristics test of the servo valve power-level slide valve pair can only test the axial fluid force. Since the radial clearance of the slide valve is extremely small, the radial offset state of the valve core in the main hole of the valve sleeve is difficult to determine, and the influence of contact pressure on the measurement is difficult to eliminate; at the same time, placing sensor measurement points on the surface of the valve core will cause great interference to the flow state of the small gap flow field, affecting the test accuracy. Therefore, the measurement of the radial fluid force of the valve core was difficult to achieve in the past.

[0003] Shanghai Kaiquan Pump Industry's patent 202410139537.X "A device and method for measuring the axial force and radial force of a centrifugal pump rotor system using a magnetic bearing" proposes a device and method for measuring the axial force and radial force of a centrifugal pump rotor system; Lanzhou University of Technology's patent CN202311795356.4 "A hydraulic force test device for a cartridge-type reversing valve" proposes a hydraulic force test device for a cartridge-type reversing valve; Harbin Electric Power Equipment Co., Ltd.'s patent CN201210306084 "Hydraulic model test device for water pumps" proposes a hydraulic model test device for water pumps.

[0004] The above patent solution fails to realize the following functions simultaneously or partially:

[0005] (1) Determination of the contact state of small radial clearance;

[0006] (2) Testing of the radial force of the liquid flow on the valve core;

[0007] (3) The influence of the contact pressure at the measuring point on the radial force and radial displacement measurement is eliminated. Summary of the invention

[0008] The technical problem solved by the present invention is: to provide a sliding valve radial fluid flow force measurement system and testing method, the method can determine the radial contact state of the valve core and the valve sleeve and obtain the radial fluid flow force exerted on the valve core, and obtain the radial resultant force and resultant moment exerted on the valve core, thereby solving the problem that the radial fluid flow force of the sliding valve with a micron-level tiny radial clearance is difficult to measure.

[0009] The technical solution adopted by the present invention is as follows:

[0010] A sliding valve radial fluid force measurement system, comprising:

[0011] Hydraulic energy, which inputs liquid oil into the interior of the tested valve housing through the oil inlet hole provided in the tested valve housing;

[0012] The valve core extension rod comprises two valve core extension rods, one end of which extends into the interior of the tested valve housing and is connected and fixed to the tested valve core, and the other end is connected to the force sensor and the displacement sensor;

[0013] The force sensor comprises two force sensors with push rods, which are respectively fixedly mounted on the ends of two valve core extension rods and are mounted in opposite directions, and are used to measure the fluid force exerted on the valve core of the tested valve; the two force sensors with push rods can move in the same direction or in opposite directions;

[0014] The displacement sensor comprises two displacement sensors, which are respectively mounted at the ends of two valve core extension rods and are mounted opposite to the force sensor with a push rod, and are used to measure the relative displacement of the valve core (8) of the valve under test;

[0015] The processor drives two force sensors with push rods to move in the same direction or in opposite directions, collects the fluid force data measured by the force sensor and the relative displacement data measured by the displacement sensor, records the offset displacement of the two sides of the valve core of the tested valve moving in the same direction in the tested valve housing or the rotational displacement of the valve core of the tested valve in the tested valve housing according to the relative displacement data measured by the displacement sensor, and obtains the resultant force of the fluid force on the valve core of the tested valve or the resultant torque of the fluid acting on the valve core of the tested valve.

[0016] The above-mentioned sliding valve radial fluid force measurement system also includes a flow meter installed on the oil inlet pipeline connecting the hydraulic energy source and the oil inlet hole of the valve housing to be measured, and is used to measure the flow rate of liquid oil.

[0017] The above-mentioned sliding valve radial fluid force measurement system also includes a pressure sensor installed on the oil inlet pipeline connecting the hydraulic energy source and the oil inlet hole of the valve body to be tested, and is used to measure the pressure of the oil inlet port of the valve body to be tested.

[0018] The above-mentioned sliding valve radial fluid force measurement system also includes an oil return stop valve, which is installed on the oil outlet pipeline connected to the oil outlet hole of the measured valve housing and is used to control the inside of the measured valve housing to be in a static pressure state or a working flow state.

[0019] The above-mentioned sliding valve radial fluid force measurement system also includes an oil container for receiving liquid oil flowing out of the valve housing to be measured.

[0020] In the above-mentioned sliding valve radial fluid flow force measurement system, one end of the two valve core extension rods respectively extends into the interior of the valve housing to be measured and is tightened and fixed to the valve core of the valve to be measured by threads, and the other end is provided with two relative installation planes near the end position, on which the force sensor and the displacement sensor are respectively installed.

[0021] In the above-mentioned sliding valve radial fluid flow force measurement system, when the processor drives the two force sensors with push rods to move in the same direction, the valve core of the measured valve is pressed against the inner wall of the valve housing cavity under test, and the sum of the fluid flow forces measured by the two force sensors with push rods is the resultant fluid flow force exerted on the valve core of the measured valve; when the processor drives the two force sensors with push rods to move in opposite directions, the valve core of the measured valve rotates around the center in the valve housing cavity under test, and the resultant torque of the fluid acting on the valve core of the measured valve is calculated based on the fluid flow force measured by the force sensor with push rod and the structural parameters of the valve core of the measured valve.

[0022] In the above-mentioned sliding valve radial fluid force measurement system, the processor obtains the resultant fluid force exerted on the valve core of the measured valve or the resultant torque of the fluid acting on the valve core of the measured valve between the starting point and the ending point where the valve core of the measured valve separates from the inner wall of the valve housing cavity of the measured valve, wherein the time point when the relative displacement data of the valve core of the measured valve measured by the displacement sensor changes from static to changing is the starting point, and the time point when the relative displacement data stops changing is the ending point.

[0023] In the above-mentioned sliding valve radial fluid flow force measurement system, the processor also includes: a push rod on the driving force sensor, which determines the position state of the valve core of the tested valve through the displacement sensor, specifically: when the displacement sensor reading changes, it indicates that the valve core of the tested valve is separated from the inner wall surface of the tested valve housing and starts to move; when the displacement sensor reading stops changing, it indicates that the valve core of the tested valve is in contact with the inner wall surface of the tested valve housing again, and the middle position of both sides of the valve core of the tested valve in the cavity of the tested valve housing is calculated, that is, the position where the axis of the valve core of the tested valve coincides with the axis of the cavity of the tested valve housing.

[0024] A method for measuring radial fluid flow force of a sliding valve, applied to the above-mentioned measurement system, specifically comprises the following steps:

[0025] The hydraulic energy inputs the liquid oil into the tested valve housing through the oil inlet hole opened in the tested valve housing, and then flows to the oil container to return the oil after passing through the gap between the tested valve core and the tested valve housing cavity. When the oil return stop valve is closed, the inside of the tested valve housing is in a static pressure state, and when the oil return stop valve is opened, the inside of the tested valve housing is in a working flow state;

[0026] The processor pushes the push rod on the force sensor to determine the position state of the valve core of the tested valve through the displacement sensor. Specifically, when the displacement sensor reading changes, it indicates that the valve core of the tested valve is separated from the inner wall surface of the tested valve housing and starts to move. When the displacement sensor reading stops changing, it indicates that the valve core of the tested valve is in contact with the inner wall surface of the tested valve housing again. The middle position of both sides of the valve core of the tested valve in the cavity of the tested valve housing is calculated.

[0027] The processor drives two force sensors with push rods to move in the same direction, and the valve core of the tested valve is pressed against the inner wall of the valve housing cavity. The sum of the liquid flow forces measured by the two force sensors with push rods is the resultant liquid flow force on the valve core of the tested valve.

[0028] The processor drives two force sensors with push rods to move in opposite directions, and the valve core of the tested valve rotates around the center in the valve housing cavity. The resultant torque of the liquid flow acting on the valve core of the tested valve is calculated based on the liquid flow force measured by the force sensor with push rod and the structural parameters of the valve core of the tested valve.

[0029] Compared with the prior art, the present invention has at least the following beneficial effects:

[0030] (1) An embodiment of the present invention proposes a system and method for measuring the radial fluid force of a sliding valve. The measurement system includes a hydraulic energy source, a force sensor with a push rod, a displacement sensor, a valve core extension rod, and a processor. The radial offset of the valve core in the cavity (main hole) can be adjusted by the push rod on the force sensor. The radial displacement of the valve core can be collected by the displacement sensor to determine the position of the valve core in the cavity (main hole) during the measurement process. The radial resultant force and resultant torque acting on the valve core at any moment when the valve core is separated from the cavity (main hole) can be obtained by collecting data from the force sensor at any moment when the valve core is separated from the cavity (main hole).

[0031] (2) In the embodiment of the present invention, the force sensor and the displacement sensor are used to collect data simultaneously. The valve core displacement change curve can be used to judge the time when the valve core separates from the wall and contacts the wall, as well as the radial offset of the valve core at any time during the time period, thereby eliminating the influence of the valve core contacting the wall on the radial force measurement.

[0032] (3) In the embodiment of the present invention, the extension rods at both ends of the valve core can provide external measuring points for the force sensor and the displacement sensor, thereby avoiding interference with the gap flow field and making the test state consistent with the actual working state; and the extension rods at both ends of the valve core can amplify the deflection displacement of the valve core inside the main hole, thereby improving the accuracy of radial micro-displacement measurement;

[0033] (4) The embodiment of the present invention adopts a force sensor with a push rod. Through the push rod with bidirectional movement, the valve core can move in translation in the main hole and rotate around the axial center, thereby achieving adjustment of any radial position;

[0034] (5) The embodiment of the present invention can measure the radial liquid flow resultant force and resultant moment at any time by collecting the full-time force during the time period when the valve core is separated from the wall; and can obtain the relationship between the radial liquid flow resultant force and resultant moment and the radial deviation by collecting the radial offset and radial force of the valve core at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1It is a schematic diagram of the structure of the radial fluid flow force measurement system of the slide valve in an embodiment of the present invention;

[0036] Figure 2 Schematic diagram of the radial force and displacement measurement of the valve core in an embodiment of the present invention;

[0037] Figure 3 A schematic diagram of a processor sampling and interpretation method according to an embodiment of the present invention;

[0038] 1- hydraulic energy source, 2- flow meter, 3- pressure sensor, 4- oil return stop valve, 5- force sensor with push rod, 6- displacement sensor, 7- tested valve housing, 8- tested valve core, 9- valve core extension rod, 10- processor, 11- oil container. DETAILED DESCRIPTION

[0039] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments:

[0040] like Figure 1 As shown, the radial fluid force measurement system of the sliding valve in the embodiment of the present invention includes a hydraulic energy source 1, a flow meter 2, a pressure sensor 3, an oil return stop valve 4, two force sensors with push rods 5, two displacement sensors 6, a valve housing 7, a valve core 8, two valve core extension rods 9, a processor 10 and an oil container 11.

[0041] The hydraulic energy source 1 inputs the liquid oil into the cavity (main hole) of the tested valve housing 7 through the oil inlet hole opened in the tested valve housing 7. The hydraulic energy source 1 can adjust the inlet pressure of the measuring system. The flow meter 2 is installed on the oil inlet pipeline connecting the hydraulic energy source 1 with the oil inlet hole of the tested valve housing 7, and is used to measure the flow of the liquid oil and determine whether the measuring system is working normally. The pressure sensor 3 is installed on the oil inlet pipeline connecting the hydraulic energy source 1 with the oil inlet hole of the tested valve housing 7, and is used to measure the pressure of the oil inlet of the tested valve housing 7. The return oil stop valve 4 is installed on the oil outlet pipeline connecting the oil outlet hole of the tested valve housing 7, and is used to control the inside of the tested valve housing 7 to be in a static pressure state or a working flow state. The oil container 11 is used to receive the liquid oil flowing out of the tested valve housing 7. The hydraulic oil enters the oil inlet hole on the tested valve housing 7, passes through the gap between the tested valve core 8 and the tested valve housing and the main hole of the valve sleeve, and then flows to the oil container 11 to return the oil. In this embodiment, the oil container 11 is an oil tank. When the oil return stop valve 4 is closed, the interior of the tested valve is in a static pressure state; when the oil return stop valve 4 is opened, the interior of the tested valve is in a working flow state.

[0042] like Figure 2As shown, two valve core extension rods 9 extend from both ends into the main hole of the valve housing 7 to be tested and are fixed to the valve core 8 of the valve to be tested by screwing. Two opposite installation planes are opened near the end positions of the other ends of the two valve core extension rods 9, and the force sensor 5 and the displacement sensor 6 are installed respectively. Among them, two force sensors 5 with push rods are fixedly installed above or below the end planes of the two valve core extension rods 9, and the installation directions are opposite. They are used to measure the liquid flow force on the valve core 8 of the valve to be tested. The two force sensors 5 with push rods can move in the same direction or in the opposite direction under the drive of the push rods. Two displacement sensors 6 are installed above or below the end planes of the two valve core extension rods, and are installed opposite to the force sensors with push rods, and are used to measure the relative displacement of the valve core 8 of the valve to be tested.

[0043] The processor 10 pushes the push rod on the force sensor 5 and determines the position state of the valve core 8 of the tested valve through the displacement sensor 6, specifically: when the reading of the displacement sensor 6 changes, it indicates that the valve core 8 of the tested valve separates from the inner wall surface of the tested valve housing 7 and starts to move; when the reading of the displacement sensor 6 stops changing, it indicates that the valve core 8 of the tested valve contacts the inner wall surface of the tested valve housing 7 again, and the middle position of the two sides of the valve core 8 of the tested valve in the main hole of the tested valve housing 7 is calculated, that is, the position where the axis of the valve core 8 of the tested valve coincides with the axis of the cavity of the tested valve housing 7.

[0044] When the processor 10 drives the two force sensors with push rods to move in the same direction, the valve core 8 of the tested valve is pressed against the inner wall of the cavity of the tested valve housing 7, and the sum of the fluid force measured by the two sensors with push rods is the resultant force of the fluid force on the valve core 8 of the tested valve. When the processor 10 drives the two force sensors with push rods to move in opposite directions, the valve core 8 of the tested valve rotates around the center in the cavity of the tested valve housing 7, and the resultant torque of the fluid acting on the valve core 8 of the tested valve or the relationship between the resultant torque and the displacement is calculated based on the fluid force measured by the force sensor with push rod and the structural parameters (lever arm) of the valve core 8 of the tested valve.

[0045] In the embodiment of the present invention, the processor obtains the resultant force of the liquid flow acting on the valve core 8 of the valve under test or the resultant torque of the liquid flow on the valve core 8 of the valve under test between the starting point and the ending point when the valve core 8 of the valve under test is separated from the inner wall of the cavity of the valve housing 7 of the valve under test, wherein the time point when the relative displacement data of the valve core 8 of the valve under test measured by the displacement sensor 6 changes from static to changing is the starting point, and the time point when the relative displacement data stops changing is the ending point.

[0046] The present invention provides a method for measuring radial fluid flow force of a sliding valve, which is applied to the above-mentioned measurement system and specifically comprises the following steps:

[0047] (1) The hydraulic energy source 1 inputs the liquid oil into the tested valve housing 7 through the oil inlet hole opened in the tested valve housing 7, and then flows to the mailbox 11 to return the oil after passing through the gap between the tested valve core 8 and the cavity of the tested valve housing 7. When the oil return stop valve 4 is closed, the interior of the tested valve housing 7 is in a static pressure state. When the oil return stop valve 4 is opened, the interior of the tested valve housing 7 is in a working flow state.

[0048] (2) The processor 10 pushes the push rod on the force sensor 5 to determine the position state of the valve core 8 of the tested valve through the displacement sensor 6. Specifically, when the reading of the displacement sensor 6 changes, it indicates that the valve core 8 of the tested valve is separated from the inner wall surface of the tested valve housing 7 and starts to move. When the reading of the displacement sensor 6 stops changing, it indicates that the valve core 8 of the tested valve is in contact with the inner wall surface of the tested valve housing 7 again. The middle position of both sides of the valve core 8 of the tested valve in the cavity of the tested valve housing 7 is calculated;

[0049] (3) The processor 10 drives the two force sensors with push rods to move in the same direction, and the valve core 8 of the tested valve is pressed against the inner wall of the cavity of the tested valve housing 7. The sum of the liquid flow forces measured by the two force sensors with push rods is the resultant liquid flow force on the valve core (8) of the tested valve;

[0050] (4) The processor 10 drives the two force sensors with push rods to move in opposite directions, and the valve core 8 of the tested valve rotates around the center in the cavity of the tested valve housing 7. The resultant torque of the liquid flow acting on the valve core 8 of the tested valve is calculated based on the liquid flow force measured by the force sensor with push rod and the structural parameters of the valve core 8 of the tested valve.

[0051] In the above steps (3) and (4), the processor obtains the resultant force or torque of the fluid force between the starting point and the ending point where the valve core 8 of the tested valve separates from the inner wall of the cavity of the tested valve housing 7, wherein the time point when the relative displacement data of the valve core 8 of the tested valve measured by the displacement sensor 6 changes from static to changing is the starting point, and the time point when the relative displacement data stops changing is the ending point.

[0052] like Figure 3 The figure shows a schematic diagram of the processor sampling and interpretation method in an embodiment of the present invention. It can be seen from the figure that between the starting point and the end point, the displacement value measured by the displacement sensor 6 and the force value data measured by the force sensor 5 can obtain the relationship between the radial liquid flow force and the relative position of the valve core 8 of the tested valve in the cavity of the tested valve housing 7.

[0053] In the embodiment of the present invention, the radial offset of the valve core in the main hole can be adjusted by the push rod on the force sensor; the radial displacement of the valve core can be collected by the displacement sensor to determine the position of the valve core in the main hole during the measurement process; the radial resultant force and resultant moment of the valve core at any moment when the valve core is separated from the main hole can be obtained by collecting data by the force sensor. The system and method can determine the radial contact state between the valve core and the valve sleeve and obtain the radial liquid flow force on the valve core, solving the problem that the radial liquid flow force of the sliding valve with a micron-level radial clearance is difficult to measure.

[0054] The above description is only the best specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

[0055] The contents not described in detail in the specification of the present invention belong to the common knowledge of the professionals in this field.

Claims

1. A sliding valve radial fluid force measurement system, characterized in that: include: A hydraulic energy source (1) is used to input liquid oil into the interior of the tested valve housing (7) through an oil inlet hole provided in the tested valve housing (7); The valve core extension rod (9) comprises two valve core extension rods, one end of which extends into the interior of the tested valve housing (7) and is connected and fixed to the tested valve core (8), and the other end of which is connected to the force sensor (5) and the displacement sensor (6); The force sensor (5) comprises two force sensors with push rods, which are respectively fixedly mounted on the ends of two valve core extension rods and are mounted in opposite directions, and are used to measure the liquid flow force exerted on the valve core (8) of the tested valve; the two force sensors with push rods can move in the same direction or in opposite directions; The displacement sensor (6) comprises two displacement sensors, which are respectively mounted on the ends of two valve core extension rods and are mounted opposite to the force sensor with a push rod, and are used to measure the relative displacement of the valve core (8) of the valve under test; The processor (10) drives two force sensors with push rods to move in the same direction or in opposite directions, collects the fluid force data measured by the force sensor (5) and the relative displacement data measured by the displacement sensor (6), and records the offset displacement of the two sides of the valve core (8) of the tested valve moving in the same direction in the tested valve housing (7) or the rotational displacement of the valve core (8) of the tested valve in the tested valve housing (7) according to the relative displacement data measured by the displacement sensor (6), so as to obtain the resultant force of the fluid force on the valve core (8) of the tested valve or the resultant torque of the fluid acting on the valve core (8) of the tested valve.

2. The slide valve radial fluid force measurement system according to claim 1, characterized in that: It also includes a flow meter (2) installed on an oil inlet pipeline connecting the hydraulic energy source (1) and the oil inlet hole of the valve housing (7) to be tested, and used to measure the flow rate of liquid oil.

3. The slide valve radial fluid force measurement system according to claim 1, characterized in that: It also includes a pressure sensor (3) installed on an oil inlet pipeline connecting the hydraulic energy source (1) and the oil inlet hole of the tested valve housing (7), and used to measure the pressure of the oil inlet port of the tested valve housing (7).

4. The slide valve radial fluid force measurement system according to claim 1, characterized in that: It also includes an oil return stop valve (4) installed on an oil outlet pipeline connected to the oil outlet hole of the tested valve housing (7) and used to control the interior of the tested valve housing (7) to be in a static pressure state or a working flow state.

5. The slide valve radial fluid force measurement system according to claim 1, characterized in that: It also includes an oil container (11) for receiving liquid oil flowing out of the tested valve housing (7).

6. The slide valve radial fluid force measurement system according to claim 1, characterized in that: One end of the two valve core extension rods respectively extends into the interior of the tested valve housing (7) and is screwed and fixed to the tested valve core (8) through threads, and the other end is provided with two opposite installation planes near the end position, on which the force sensor (5) and the displacement sensor (6) are respectively installed.

7. The slide valve radial fluid force measurement system according to claim 1, characterized in that: When the processor (10) drives the two force sensors with push rods to move in the same direction, the valve core (8) of the tested valve is pressed against the inner wall of the cavity of the tested valve housing (7), and the sum of the liquid flow forces measured by the two force sensors with push rods is the resultant liquid flow force acting on the valve core (8) of the tested valve; when the processor (10) drives the two force sensors with push rods to move in opposite directions, the valve core (8) of the tested valve rotates around the center in the cavity of the tested valve housing (7), and the resultant torque of the liquid flow acting on the valve core (8) of the tested valve is calculated based on the liquid flow force measured by the force sensor with push rod and the structural parameters of the valve core (8) of the tested valve.

8. The slide valve radial fluid force measurement system according to claim 1, characterized in that: The processor obtains the resultant force of the liquid flow acting on the valve core (8) of the tested valve or the resultant torque of the liquid flow acting on the valve core (8) of the tested valve between the starting point and the ending point when the valve core (8) of the tested valve is separated from the inner wall surface of the cavity of the valve housing (7) of the tested valve, wherein the time point when the relative displacement data of the valve core (8) of the tested valve measured by the displacement sensor (6) changes from being stationary to changing is the starting point, and the time point when the relative displacement data stops changing is the ending point.

9. The sliding valve radial fluid force measurement system according to claim 1, characterized in that: The processor (10) further comprises: a push rod on the driving force sensor (5), which determines the position state of the valve core (8) of the tested valve through the displacement sensor (6), specifically: when the reading of the displacement sensor (6) changes, it indicates that the valve core (8) of the tested valve is separated from the inner wall surface of the tested valve housing (7) and starts to move; when the reading of the displacement sensor (6) stops changing, it indicates that the valve core (8) of the tested valve is in contact with the inner wall surface of the tested valve housing (7) again, and the middle position of the two sides of the valve core (8) of the tested valve in the cavity of the tested valve housing (7) is calculated, that is, the position where the axis of the valve core (8) of the tested valve coincides with the axis of the cavity of the tested valve housing (7).

10. A method for measuring radial fluid flow force of a sliding valve, characterized in that: The measurement system according to any one of claims 1 to 9 specifically comprises the following steps: The hydraulic energy (1) inputs liquid oil into the interior of the tested valve housing (7) through the oil inlet hole provided in the tested valve housing (7), and then flows to the oil container (11) to return the oil after passing through the gap between the tested valve core (8) and the cavity of the tested valve housing (7). When the oil return stop valve (4) is closed, the interior of the tested valve housing (7) is in a static pressure state, and when the oil return stop valve (4) is opened, the interior of the tested valve housing (7) is in a working flow state. The processor (10) pushes the push rod on the force sensor (5) to determine the position state of the valve core (8) of the tested valve through the displacement sensor (6), specifically: when the reading of the displacement sensor (6) changes, it indicates that the valve core (8) of the tested valve is separated from the inner wall surface of the tested valve housing (7) and starts to move; when the reading of the displacement sensor (6) stops changing, it indicates that the valve core (8) of the tested valve is in contact with the inner wall surface of the tested valve housing (7) again, and the middle position of the two sides of the valve core (8) of the tested valve in the cavity of the tested valve housing (7) is calculated; The processor (10) drives the two force sensors with push rods to move in the same direction, and the valve core (8) of the valve under test is pressed against one side of the inner wall surface of the cavity of the valve housing (7) under test, and the sum of the liquid flow forces measured by the two force sensors with push rods is the resultant liquid flow force on the valve core (8) of the valve under test; The processor (10) drives the two force sensors with push rods to move in opposite directions, and the valve core (8) of the tested valve rotates around the center in the cavity of the tested valve housing (7). The resultant torque of the liquid flow acting on the valve core (8) of the tested valve is calculated based on the liquid flow force measured by the force sensor with push rod and the structural parameters of the valve core (8) of the tested valve.

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