Real-time in-situ measurement device and method for dynamic erosion rate of hydraulic servo spool valve port working edge

Abstract

The application discloses a device and method for real-time in-situ measurement of dynamic erosion rate of a hydraulic servo spool valve port working edge, which adopts a modelized spool valve structure, takes the valve port working edge as a measurement object, adjusts the spool displacement through a high-precision micrometer, and measures the dynamic erosion rate of the working edge under different valve port openings. The erosion characteristic regions of the spool and the valve body working edge are respectively provided with wedge-shaped resistance probes, the probes can be arranged relatively or in an interlaced mode, cover both sides of the valve port and different erosion positions, and realize global measurement of the working edge erosion. When the oil liquid containing particles flows through the valve port, the erosion will reduce the effective conductive cross-sectional area of the probe and cause resistance change, the measurement signal is continuously transmitted to an external data acquisition system through a lead interface, and then the real-time dynamic erosion rate of the working edge is obtained through a valve port working edge erosion rate calculation formula. The device can realize in-situ, real-time and global measurement of the hydraulic servo spool valve port working edge erosion rate under an actual flow state without stopping and disassembling the hydraulic valve.

Description

Technical Field

[0001] This invention relates to a real-time measurement technology for dynamic erosion rate of hydraulic valves, applicable to in-situ measurement of dynamic erosion rate of the working edge of a hydraulic servo spool valve orifice. Background Technology

[0002] Erosion is a form of wear that damages a material surface through repeated impacts from flowing particles. In hydraulic systems, solid particles in the hydraulic fluid move at high speeds with the fluid flow and impact the surface of components when passing through high-speed local areas such as throttling orifices and valve ports, causing material removal and changes in surface morphology. Hydraulic servo valves are crucial control components in hydraulic servo systems; the working edge formed between the valve core and valve sleeve directly affects the valve opening, flow area, and flow control characteristics. When particulate-containing hydraulic fluid flows through the valve port of a hydraulic servo valve, the particles impact, cut, and scour the working edges of the valve core and valve sleeve, gradually rounding off sharp edges or causing localized defects. As erosion time increases, the flow area and throttling edge morphology change, leading to increased zero-point leakage, decreased flow gain and pressure gain, and in severe cases, affecting the stable operation of the hydraulic servo valve and the entire system.

[0003] Therefore, studying the dynamic erosion process of the working edge of a hydraulic servo spool valve orifice under the action of particulate oil is of great significance for valve orifice reliability design, life assessment and performance degradation analysis.

[0004] Searching existing published literature and patents, the main research on hydraulic valve port erosion and its measurement includes: 1) Analysis and structural discussion of hydraulic valve erosion wear characteristics [J] (Zhang Hong, Xiong Shibao, Liang Yiwei, Xiong Xiaoyan. Journal of Coal Science and Technology, 2008, 33(02): 214-217). Using CFD method and erosion model to analyze particle erosion in high water-based planar pilot valve, it was found that valve core erosion is mainly concentrated near the throttling orifice, and the superposition of erosion and fretting wear will accelerate valve core damage; 2) Separate valve port erosion visualization measurement device and usage method [P] (Liu Xinqiang, Liu Xiaoxiong, Ji Hong, Liu Fei, Zhang Jianjun, Li Nana). CN112067426A, 2020-12-11) The interaction process between particles and the working edge of the valve port is observed using a high-speed camera, and the valve port plate is removed after a set time. The erosion morphology at different stages is measured by a three-dimensional surface morphology instrument; 3) A valve port erosion prediction method and a valve port leakage compensation control method [P] (Liu Xiaochao, Bing Lu, Qi Pengyuan, Li Dingbo, Jiao Zongxia). CN115659860A, 2023-01-31) Establishes a valve port erosion rate function through multi-condition simulation and least squares fitting, calculates erosion amount, erosion profile, flow area and leakage flow, and performs leakage compensation accordingly; 4) A method for measuring valve port erosion wear of a slide valve [P] (Yin Yaobao, Li Shuanglu. CN113567108A, 2021-10-29) Iteratively calculates the change of erosion radius of valve core and valve sleeve according to the slide valve load state, valve port pressure difference and particle impact parameters, and is used to predict the valve port erosion morphology under different working times; 5) Resistance probe for corrosion monitoring [P] (Cai Zhenliang, Song Feng, Gao Jian, Lei Haitao, Ouyang Peng. CN114441433A, 2022-05-06) Measure corrosion loss and corrosion rate according to the change of resistance value after metal probe corrosion, and reduce the influence of temperature on the measurement results through heat conduction structure.

[0005] The above research on hydraulic valve orifice erosion and resistance probe measurement provides a useful reference for valve orifice erosion mechanism analysis, erosion morphology prediction, and erosion experimental device design. However, the following shortcomings still exist: (1) Existing studies on valve port erosion mainly focus on numerical simulation, empirical formula prediction or morphology measurement after erosion, making it difficult to obtain the erosion rate changes of the valve core and valve sleeve working edge in real time during the operation of hydraulic servo spool valve.

[0006] (2) Existing visualization erosion experimental devices are mainly used to record particle movement and valve port erosion process. The erosion morphology usually needs to be disassembled after the machine is stopped and measured with the help of a morphology instrument. It cannot realize the in-situ continuous measurement of the erosion rate of the working side of the valve port.

[0007] (3) Existing resistance probes are mostly used for general corrosion monitoring. Their structure and installation method are not designed for the narrow space, flow, valve core displacement adjustment and local erosion characteristics of the working side of the hydraulic servo spool valve port, making it difficult to directly use them for dynamic erosion rate measurement of the working side of the hydraulic servo spool valve port.

[0008] Therefore, it is necessary to propose a real-time in-situ measurement device and method for the dynamic erosion rate of the working edge of a hydraulic servo spool valve, so as to realize the in-situ, real-time, continuous and full-domain measurement of the erosion rate of the working edge of the valve orifice, and provide experimental basis for the research on the erosion mechanism of hydraulic servo spool valves, the design of erosion-resistant structures, and the assessment of life. Summary of the Invention

[0009] The purpose of this invention is to provide a real-time in-situ measurement device and method for the dynamic erosion rate of the working edge of a hydraulic servo spool valve orifice, in order to solve the problem that existing hydraulic servo spool valve orifice erosion measurement requires shutdown and disassembly, and offline measurement, and cannot obtain the erosion rate of the working edge of the valve core and valve sleeve in real time during operation.

[0010] This invention relates to a real-time in-situ measurement device and method for the dynamic erosion rate of the working edge of a hydraulic servo spool valve. The measuring device includes a sealing ring 1, a high-precision micrometer valve opening adjustment mechanism 2, a right end cover 3, an oil inlet P port 4, a load port A port 5, a return spring 6, an end cover fastening screw 7, a left end cover 8, a lead wire interface 8a, a valve body fastening screw 9, a valve core 10, a valve core resistance probe 11 including a first valve core resistance probe 11a, a second valve core resistance probe 11b, a third valve core resistance probe 11c, and a fourth valve core resistance probe 11d, a valve sleeve 12, and a valve sleeve resistance probe 13 including a first valve sleeve resistance probe 13a, a second valve sleeve resistance probe 13b, a third valve sleeve resistance probe 13c, and a fourth valve sleeve resistance probe 13d. The valve core 10 is installed inside the valve sleeve 12, and the oil inlet... Port P4 and load port A5 are located below valve sleeve 12 to simulate the erosion condition of the working edge of the valve port during the operation of the hydraulic servo spool valve. The high-precision micrometer valve port opening adjustment mechanism 2 is connected to the valve core 10 and cooperates with the return spring 6 to adjust the axial displacement of the valve core 10 and the valve port opening. The valve core resistance probe 11 and the valve sleeve resistance probe 13 are respectively arranged in the characteristic areas of the working edge of the valve port of the valve core 10 and the valve sleeve 12. The resistance probes are installed in the corresponding wedge-shaped mounting grooves and are fixed and insulated. The leads of the valve core resistance probe 11 and the valve sleeve resistance probe 13 are connected to the external data acquisition system through the lead interface 8a to transmit the resistance change signal in real time during the operation of the hydraulic servo spool valve, thereby realizing the real-time in-situ measurement of the dynamic erosion rate of the working edge of the valve port.

[0011] The measurement method using the above-described hydraulic servo spool valve orifice dynamic erosion rate real-time in-situ measurement device has the following steps: Step (1) Record the initial resistance value R0 of the resistance probe; Step (2) Adjust the axial displacement of the valve core (10) by using the high-precision micrometer valve opening adjustment mechanism (2) to set the required valve opening, so that the working medium flows between the oil inlet P port (4) and the load port A port (5). Step (3) During the operation of the slide valve pair, the resistance change signal is collected in real time and recorded. T i resistance value at time R i and T t resistance value at time R t The dynamic erosion rate of the working edge of the valve core (10) and valve body (12) is calculated based on the resistance change and the following formula: ; In the formula, E r The dynamic erosion rate is represented by 'a', and the length of the hypotenuse of the wedge-shaped resistor probe cross-section is represented by 'a'. R 0 represents the initial resistance value of the resistance probe; R i and R t They are respectively T i and T t The resistance value measured at any time T t - T i 8760 represents the time interval between the two measurements; 8760 represents the number of hours in a year.

[0012] Compared with the prior art, the present invention has the following advantages: The present invention simplifies the valve port area from the oil inlet P port to the load port A port of the hydraulic servo spool valve into a modeled spool valve pair measurement structure, which enables real-time in-situ measurement; by adjusting the position of the valve core 10 through the high-precision micrometer valve port opening adjustment mechanism 2, erosion measurement conditions under different valve port openings can be obtained; by arranging resistance probes in the erosion characteristic area of ​​the working edge of the valve core 10 and the valve sleeve 12, the cross-sectional area change caused by the working edge erosion is converted into a resistance signal output, eliminating the need to stop the machine and disassemble the specimen for morphological inspection during each measurement, and enabling real-time in-situ measurement of the dynamic erosion rate of the working edge of the hydraulic servo spool valve port. By changing the arrangement position of the resistance probes, full-area measurement of the working edge of the valve port can be achieved, providing experimental basis for valve port erosion mechanism analysis, erosion-resistant structure design and life assessment. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the experimental apparatus of the present invention. Figure 2 This is a cross-sectional view of the valve core of the experimental model of this invention. Figure 3This is a schematic diagram of the valve core resistance probe structure of the present invention. Figure 4 This is a structural diagram of the valve sleeve of the experimental model of this invention. Figure 5 This is a schematic diagram of the valve sleeve resistance probe structure of the present invention. Figure 6 The relative arrangement is formed by fixing the positions of the valve sleeve resistance probes. Figure 7 It is an alternating arrangement formed by fixing the positions of the valve sleeve resistance probes. Figure 8 The relative arrangement is formed by fixing the positions of the valve core resistance probes. Figure 9 It is an alternating arrangement formed by fixing the position of the valve core resistance probe.

[0014] The attached figures and their corresponding names are as follows: 1-Sealing ring, 2-High-precision micrometer valve port opening adjustment mechanism, 3-Right end cap, 4-Oil inlet P port, 5-Load port A port, 6-Reset spring, 7-End cap fastening screw, 8-Left end cap, 8a-Lead wire interface, 9-Valve sleeve fastening screw, 10-Valve core, 11-Valve core resistance probe, including first valve core resistance probe 11a, second valve core resistance probe 11b, third valve core resistance probe 11c, and fourth valve core resistance probe 11d, 12-Valve sleeve, 13-Valve sleeve resistance probe, including first valve sleeve resistance probe 13a, second valve sleeve resistance probe 13b, third valve sleeve resistance probe 13c, and fourth valve sleeve resistance probe 13d. Detailed Implementation

[0015] like Figures 1-9 As shown, this invention relates to a real-time in-situ measurement device and method for the dynamic erosion rate of the working edge of a hydraulic servo spool valve port. The measuring device includes a sealing ring 1, a high-precision micrometer valve port opening adjustment mechanism 2, a right end cover 3, an oil inlet P port 4, a load port A port 5, a return spring 6, an end cover fastening screw 7, a left end cover 8, a lead wire interface 8a, a valve sleeve fastening screw 9, a valve core 10, a valve core resistance probe 11 including a first valve core resistance probe 11a, a second valve core resistance probe 11b, a third valve core resistance probe 11c, and a fourth valve core resistance probe 11d, a valve sleeve 12, and a valve sleeve resistance probe 13 including a first valve sleeve resistance probe 13a, a second valve sleeve resistance probe 13b, a third valve sleeve resistance probe 13c, and a fourth valve sleeve resistance probe 13d.

[0016] The valve core 10 is installed inside the valve sleeve 12, which has an oil inlet port P 4 and a load port A 5. During the experiment, oil containing particles enters through port P 4, flows through the valve port area formed between the valve core 10 and the valve sleeve 12, and exits through the load port A 5. The right end cap 3 and the left end cap 8 are respectively located on both sides of the valve sleeve 12 and are fixed by the end cap fastening screws 7. The sealing ring 1 is located at the mating position between the end cap and the valve sleeve 12 to prevent oil leakage.

[0017] The high-precision micrometer valve opening adjustment mechanism 2 is located on one side of the right end cover 3 and is connected to the valve core 10. The return spring 6 is located on the other side of the valve core 10. In use, the valve core 10 is moved axially by rotating the high-precision micrometer adjustment mechanism 2. The return spring 6 is used to ensure that the valve core 10 returns to its original position and is stably positioned, thereby adjusting the valve opening between the valve core 10 and the valve sleeve 12.

[0018] The valve core resistance probe 11 is positioned at the working edge of the valve port of the valve core 10, and the valve sleeve resistance probe 13 is positioned at the working edge of the valve port of the valve sleeve 12. Wedge-shaped mounting grooves are machined on both the valve core 10 and the valve sleeve 12. The valve core resistance probe 11 and the valve sleeve resistance probe 13 are respectively embedded in their corresponding wedge-shaped mounting grooves and are fixed and insulated. The arrangement methods can be as follows: Figure 6 The relative arrangement formed by fixing the position of the resistance probe in the middle valve sleeve. Figure 7 The phase-to-phase arrangement is formed by fixing the position of the resistor probe in the middle valve sleeve. Figure 8 The relative arrangement formed by the fixed position of the valve core resistance probe. Figure 9 The alternating arrangement of the valve core resistance probes with fixed positions enables full-range measurement of the dynamic erosion rate of the working edge of the valve port. The leads of the valve core resistance probes (11a-d) and the valve sleeve resistance probes (13a-d) are led out through the lead interface (8a) and connected to an external data acquisition system.

[0019] The method of using the measuring device described in this invention comprises the following steps: Step (1) Record the initial resistance value R0 of the resistance probe; Step (2) Adjust the axial displacement of the valve core 10 by adjusting the valve opening degree adjustment mechanism 2 of the high precision micrometer valve opening degree, and set the required valve opening degree so that the working medium flows between the oil inlet P port (4) and the load port A port (5). Step (3) During the operation of the slide valve pair, the resistance change signal is collected in real time and recorded. T i resistance value at time R i and T t resistance value at time R t The dynamic erosion rate of the working edge of the valve core (10) and valve body (12) is calculated based on the resistance change and the following formula: (1) In the formula, E r The dynamic erosion rate is represented by 'a', and the length of the hypotenuse of the wedge-shaped resistor probe cross-section is represented by 'a'. R 0 represents the initial resistance value of the resistance probe; R i and Rt They are respectively T i and T t The resistance value measured at any time T t - T i 8760 represents the time interval between the two measurements; 8760 represents the number of hours in a year.

[0020] The valve core resistance probe 11 and valve sleeve resistance probe 13 mentioned above adopt a wedge structure, and the dynamic erosion rate of the working side of the valve port is calculated according to the formula (1) based on the resistance values ​​obtained from two adjacent measurements.

[0021] Through the above steps, without disassembling the valve core 10 and valve sleeve 12, the resistance change of the working side of the valve port of the valve core 10 and valve sleeve 12 can be continuously obtained, and the dynamic erosion rate of the working side of the valve port can be calculated.

[0022] Although one embodiment of the present invention has been shown and described, those skilled in the art can adjust or replace the structural form, probe arrangement and connection method in this embodiment without departing from the principle of the present invention. The scope of protection of the present invention is defined by the claims and their equivalents.

Claims

1. A real-time in-situ measurement device for the dynamic erosion rate of the working edge of a hydraulic servo spool valve orifice, characterized in that: The measuring device includes a sealing ring (1), a high-precision micrometer valve opening adjustment mechanism (2), a right end cover (3), an oil inlet P port (4), a load port A port (5), a return spring (6), an end cover fastening screw (7), a left end cover (8), a lead wire interface (8a), a valve body fastening screw (9), a valve core (10), and a valve core resistance probe (11) including a first valve core resistance probe (11a), a second valve core resistance probe (11b), a third valve core resistance probe (11c), a fourth valve core resistance probe (11d), a valve sleeve (12), and a valve sleeve resistance probe (11a). 3) Includes a first valve sleeve resistance probe (13a), a second valve sleeve resistance probe (13b), a third valve sleeve resistance probe (13c), and a fourth valve sleeve resistance probe (13d). The valve core (10) is installed inside the valve sleeve (12). The oil inlet port P (4) and the load port A (5) are located below the valve sleeve (12) to simulate the erosion condition of the working side of the valve port during the operation of the hydraulic servo spool valve. The high-precision micrometer valve port opening adjustment mechanism (2) is connected to the valve core (10) and cooperates with the return spring (6) to adjust the axial displacement of the valve core (10) and the valve port opening. The valve core resistance probe (11) and the valve sleeve resistance probe (13) are respectively arranged in the valve port working edge feature area of ​​the valve core (10) and the valve sleeve (12). The resistance probes are installed in the corresponding wedge-shaped mounting grooves and are fixed and insulated. The leads of the valve core resistance probe (11) and the valve sleeve resistance probe (13) are connected to an external data acquisition system via the lead interface (8a) to transmit resistance change signals in real time during the operation of the hydraulic servo spool valve, thereby realizing real-time in-situ measurement of the dynamic erosion rate of the working side of the valve port.

2. The real-time in-situ measurement device for dynamic erosion rate of the working side of a hydraulic servo spool valve according to claim 1, characterized in that: The valve core resistance probe (11) and the valve sleeve resistance probe (13) are arranged in a relative or alternating manner. When arranged in a relative manner, the valve core resistance probe (11) and the valve sleeve resistance probe (13) are respectively arranged on the working side of the valve core and the working side of the valve sleeve on both sides of the same working area of ​​the valve port. When arranged in an alternating manner, the valve core resistance probe (11) and the valve sleeve resistance probe (13) are staggered along the circumferential direction of the working side of the valve port to achieve full-area measurement of the erosion rate of the working side of the valve port.

3. The measurement method using the real-time in-situ measurement device for dynamic erosion rate of the working side of the hydraulic servo slide valve orifice as described in claim 1, characterized in that, The steps are as follows: Step (1) Record the initial resistance value R0 of the resistance probe; Step (2) Adjust the axial displacement of the valve core (10) by using the high-precision micrometer valve opening adjustment mechanism (2) to set the required valve opening, so that the working medium flows between the oil inlet P port (4) and the load port A port (5). Step (3) During the operation of the slide valve pair, the resistance change signal is collected in real time and recorded. T i resistance value at time R i and T t resistance value at time R t The dynamic erosion rate of the working edge of the valve core (10) and valve body (12) is calculated based on the resistance change and the following formula: （1） In the formula, E r The dynamic erosion rate is represented by 'a', and the length of the hypotenuse of the wedge-shaped resistor probe cross-section is represented by 'a'. R 0 represents the initial resistance value of the resistance probe; R i and R t They are respectively T i and T t The resistance value measured at any time, T t - T i 8760 represents the time interval between the two measurements; 8760 represents the number of hours in a year.

4. The method for real-time in-situ measurement of dynamic erosion rate of the working edge of a hydraulic servo spool valve according to claim 3, characterized in that: The valve core resistance probe (11) and valve sleeve resistance probe (13) adopt a wedge structure, and the dynamic erosion rate of the working side of the valve port is calculated according to the formula (1) based on the resistance values ​​obtained from two adjacent measurements.

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