Automobile pipeline pressure detection device and detection method

Abstract

This invention discloses a pressure testing device for automotive pipelines, comprising a vertical container with a sealed pressurization chamber and a pressure-measuring liquid. The bottom of the vertical container has a first quick-connect fitting for connecting one end of an EPDM hose. The side and top of the vertical container have a first tee connector and a second tee connector, respectively. The first tee connector connects to the other end of the hose via the second quick-connect fitting, forming a pressure balance interface. The second tee connector connects to the pressurization chamber, forming an inflation interface. A high-pressure air source is simultaneously connected to the inflation interface and the pressure balance interface via a diverter valve to maintain pressure balance at both ends of the system. This device creates a U-shaped connection between the hose and the container, directly converting the volume expansion of the hose under pulsed pressurization into a decrease in liquid level within the vertical container, thus achieving quantitative monitoring of the pipeline expansion rate.

Description

Technical Field

[0001] This invention relates to the field of automotive pipeline testing, specifically to a device and method for testing the air pressure of automotive pipelines. Background Technology

[0002] With the rapid development of the automotive industry, higher requirements have been placed on the performance testing of automotive piping, especially EPDM (ethylene propylene diene monomer) hoses. The compressive strength and volumetric expansion rate of the hoses under simulated actual working conditions are key indicators for evaluating their quality. In the current field of automotive piping testing, hydraulic presses or pure pneumatic testing devices are commonly used to pressure test the pipes.

[0003] However, traditional hydraulic testing devices are often complex in structure, and the inertia of the liquid can interfere with measurement accuracy during high-frequency pulse pressure testing. Furthermore, cleaning up the liquid after the test is quite cumbersome. While pure air pressure testing is convenient to operate, the high compressibility of air makes it difficult to directly and accurately monitor the minute radial expansion of the hose through pressure changes, leading to significant errors in the calculation of the expansion rate.

[0004] Furthermore, existing testing equipment often has limited functionality, making it difficult to simultaneously manage gas-liquid balance control and real-time expansion monitoring within the same system. Typically, measuring the expansion rate requires precision displacement sensors or complex drainage and exhaust metering mechanisms, which not only increases the manufacturing cost of the equipment but also makes the operation process extremely cumbersome, hindering rapid sampling inspections at the end of the production line. Summary of the Invention

[0005] The purpose of this invention is to provide a pressure testing device for automotive pipelines, so as to solve the problems of cumbersome operation and difficulty in quantitatively observing the expansion state when performing pressure deformation tests on automotive pipelines.

[0006] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution: A pressure detection device for automotive pipelines, comprising: A vertical container with a closed pressure chamber containing a pressure-measuring liquid. The bottom of the vertical container has a first quick-connect fitting that connects to the pressure chamber. The first quick-connect fitting is used to connect one end of an EPDM hose. The first tee connector is fixedly installed on the side of the vertical container. The first tee connector and the two ends in the horizontal direction respectively form an air pressure balance interface and a drain valve. The first tee connector and the bottom form a second quick connector for connecting the other end of the EPDM hose. The air pressure balance interface, the drain valve and the second quick connector together constitute a tee structure. The second three-way connector is fixedly installed on the top of the vertical container. The bottom of the second three-way connector is connected to the pressure chamber. The two ends of the second three-way connector in the horizontal direction respectively form an inflation port and a pressure relief valve. The inflation port, the pressure relief valve and the bottom of the second three-way connector together constitute a three-way structure. The high-pressure gas source is connected to the inflation port through a diversion valve, and the pressure balance port is connected to the diversion valve through a connecting pipe.

[0007] Furthermore, an aluminum profile support column is fixedly installed on the side of the vertical container, and the aluminum profile support column is parallel to the vertical container. The first tee connector is fixedly connected to the aluminum profile support column by fasteners so that the vertical height of the first tee connector is adjustable.

[0008] Furthermore, the bottom of the vertical container is also provided with a liquid injection port that connects to the pressurized chamber, and the liquid injection port is equipped with an on / off valve.

[0009] Furthermore, the on / off valve is connected to a flexible hose, the other end of which is connected to a graduated cylinder piston injector.

[0010] Furthermore, a vertically extending transparent window is formed on the vertical container, and a liquid level scale is formed on the transparent window.

[0011] Furthermore, both the relief valve and the pressure relief valve are manual valves or solenoid valves.

[0012] Furthermore, the on / off valve is a manual valve.

[0013] Furthermore, it also includes a control module, which is used to control the high-pressure gas source to output pulsed air pressure with a set frequency and set pressure to the inflation interface and the air pressure balance interface.

[0014] Furthermore, a liquid level sensor is installed inside the vertical container. The liquid level sensor is connected to the control module and is used to collect the liquid level height data of the pressure measuring liquid in the pressure chamber in real time and send it to the control module.

[0015] A method for pressure testing of automotive pipelines includes the following steps: S1, connect the two ends of the EPDM hose to the first quick-connect fitting and the second quick-connect fitting respectively, so that it forms a U-shaped connecting pipe structure with the vertical container; Open the drain valve and pressure relief valve to allow the pressure-testing liquid in the vertical container to flow into the EPDM hose, and wait for the liquid level in the EPDM hose to match the liquid level in the vertical container under atmospheric pressure. S2, close the drain valve and pressure relief valve, open the high-pressure gas source, and let the gas enter the liquid above the pressure chamber and the first three-way connector respectively after passing through the diverter valve; The high-pressure gas source is controlled to periodically pressurize in the form of pulsed gas pressure. During this process, the drop in the liquid level of the pressure-measuring liquid in the vertical container is recorded, and the expansion rate of the EPDM hose is judged to be qualified. S3. After the test is completed, open the drain valve or pressure relief valve to release the residual pressure in the pipe, remove the EPDM hose and transfer it to the precision testing station for final result testing.

[0016] The beneficial effects of this invention are: This invention uses a diversion valve to simultaneously connect a high-pressure gas source to the pressure balance interface at the top of the pressure chamber and the first three-way connector, ensuring that the gas pressure at both ends of the communicating vessel structure formed by the vertical container and the EPDM hose is equal in real time. This static pressure balance mechanism eliminates the unidirectional flow of liquid caused by pressure difference, allowing the liquid level drop in the pressure-measuring liquid in the vertical container during pulse pressurization to be driven only by the volume change caused by the pressure expansion of the EPDM hose, eliminating the interference of pressure fluctuations. This directly and accurately converts the tiny radial deformation of the hose into the liquid level difference in the vertical container, achieving quantitative monitoring of the pipeline expansion status. Attached Figure Description

[0017] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0018] Figure 1 This is a schematic diagram illustrating the principle of an embodiment of the present invention; The labels in the diagram represent the following: 1-Vertical container; 1a-On / off valve; 1b-Transparent window; 1d-First quick connector; 1e-Injection port; 2-Aluminum profile support column; 3-First tee connector; 3a-Pressure balance interface; 3b-Relief valve; 3c-Second quick connector; 4-Second tee connector; 4a-Inflation interface; 4b-Pressure relief valve; 5-High-pressure air source; 6-Diverter valve; 7-Connecting pipe; 8-Fastener; 9-Hose; 10-Measuring cylinder piston injector; 11-EPDM hose. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] This embodiment provides a pressure testing device and method for automotive pipelines, aiming to solve the problems of cumbersome operation and difficulty in quantitatively observing the expansion state when conducting pressure deformation tests on automotive pipelines. Specifically, refer to... Figure 1 As shown, this air pressure detection device includes: The vertical container 1 has a closed pressure chamber inside, which contains a pressure measuring liquid. The bottom of the vertical container 1 is provided with a first quick connector 1d that connects to the pressure chamber. The first quick connector 1d is used to connect one end of the EPDM hose 11. The first three-way connector 3 is fixedly installed on the side of the vertical container 1. The first three-way connector 3 and the two ends in the horizontal direction respectively form a pressure balance interface 3a and a drain valve 3b. The first three-way connector 3 and the bottom form a second pipe quick connector 3c for connecting the other end of the EPDM hose 11. The pressure balance interface 3a, the drain valve 3b and the second pipe quick connector 3c together constitute a three-way structure. The second three-way connector 4 is fixedly installed on the top of the vertical container 1. The bottom of the second three-way connector 4 is connected to the pressure chamber. The second three-way connector 4 has an inflation port 4a and a pressure relief valve 4b at its two ends in the horizontal direction. The inflation port 4a, the pressure relief valve 4b and the bottom of the second three-way connector 4 together form a three-way structure. A high-pressure gas source 5 is connected to an inflation port 4a via a diversion valve 6, and a pressure balancing port 3a is connected to the diversion valve 6 via a connecting pipe 7. Based on this basic structure, the gas output from the high-pressure gas source 5, after passing through the diversion valve 6, enters the area above the liquid and the area above the EPDM hose 11 from the inflation port 4a and pressure balancing port 3a respectively, thus maintaining pressure balance on both sides of the U-shaped connecting structure. At this time, the lateral expansion volume of the EPDM hose 11 caused by the gas pulse pressurization is directly converted into the drop in liquid level of the pressure-measuring liquid in the vertical container 1.

[0021] In actual production testing, the EPDM hoses 11 to be tested come in various models, with different lengths and shapes. If the position of the first tee connector 3 is fixed, it cannot be smoothly connected to both ends of hoses of different lengths. To overcome the installation interference or inaccessibility issues caused by different specifications of hoses, an aluminum profile support column 2 is fixedly installed on the side of the vertical container 1. The aluminum profile support column 2 is parallel to the vertical container 1, and the first tee connector 3 is fixedly connected to the aluminum profile support column 2 by fasteners 8, so that the vertical height of the first tee connector 3 is adjustable. The tester can slide and tighten the fasteners 8 to make the height of the first tee connector 3 adapt to the length of the EPDM hose 11 currently being tested.

[0022] After confirming that pipeline expansion would cause liquid level changes, and because the pressurized chamber was closed and pressurized, testers could not directly probe inside the container to measure the specific changes in liquid level. To address the issue of external visibility of liquid level changes inside the sealed container, a vertically extending transparent window 1b was formed on the vertical container 1, with liquid level markings on the window 1b. Operators could directly read the difference in liquid level markings through the transparent window 1b.

[0023] Furthermore, when the equipment is used for the first time or the test medium is changed, it is necessary to add pressure-testing liquid to the vertical container 1. If the liquid is poured directly into the interface of the pressure test, it is not only easy to generate air bubbles that affect the pressure balance, but also impossible to accurately control the injection volume. In order to solve the problem of quantitative addition and discharge of liquid in the closed system, the bottom of the vertical container 1 is also provided with a liquid injection port 1e that connects to the pressure chamber, and the liquid injection port 1e is equipped with an on / off valve 1a.

[0024] The on / off valve 1a is connected to a flexible tube 9, and the other end of the flexible tube 9 is connected to a graduated cylinder piston injector 10. Based on this structure, the on / off valve 1a is a manual valve. Before testing, the manual on / off valve 1a is opened, and the graduated cylinder piston injector 10 is pushed to smoothly inject a specific volume of pressure-measuring liquid from bottom to top into the pressure chamber. After the injection is completed, the valve is closed.

[0025] To address the flow control requirements of fluids and gases within the pipeline during device operation, both relief valve 3b and pressure relief valve 4b are manual or solenoid valves. When configured as manual valves, they rely on manual intervention for opening and closing. However, when high consistency and frequency of operation are required during testing, manual valve operation and manual control of pulsed airflow can easily lead to time errors and pressure fluctuations. Furthermore, it is difficult to capture instantaneous liquid level changes manually by reading the scale through the transparent window 1b.

[0026] To mitigate errors from manual testing and automate the detection process, the device also includes a control module. This module controls the output of pulsed air pressure at a set frequency and pressure from the high-pressure air source 5 to the inflation port 4a and the pressure balancing port 3a. In conjunction with this automation, a liquid level sensor is installed inside the vertical container 1. This sensor is connected to the control module and collects real-time data on the liquid level in the pressure chamber, sending this data to the control module. By receiving the high-frequency data from the liquid level sensor, the control module can plot a liquid level curve that changes synchronously with the pulsed air pressure.

[0027] Based on the above-described device, this embodiment also provides a method for detecting pressure in automotive pipelines, the method comprising the following steps: S1, connect the two ends of the EPDM hose 11 to the first quick connector 1d and the second quick connector 3c respectively, so that it forms a U-shaped connecting pipe structure with the vertical container 1. Open the drain valve 3b and the pressure relief valve 4b to allow the pressure-testing liquid in the vertical container 1 to flow into the EPDM hose 11, and the excess liquid to be discharged from it. Under atmospheric pressure, wait for the liquid level in the EPDM hose 11 to be consistent with the liquid level in the vertical container 1. S2, close the drain valve 3b and the pressure relief valve 4b, open the high-pressure gas source 5, so that the gas enters the liquid above the pressure chamber and the first three-way connector 3 respectively after passing through the diversion valve 6; control the high-pressure gas source 5 to periodically pressurize in the form of pulsed air pressure, record the drop in liquid level of the pressure measuring liquid in the vertical container 1 during this process, and judge whether the expansion rate of the EPDM hose 11 is qualified based on this. In this step, the specific process for determining the expansion rate of the EPDM hose 11 is as follows: obtain the internal cross-sectional area of ​​the vertical container 1, multiply it by the recorded drop in the pressure measuring liquid level, and calculate the increase in volume of the pressure measuring liquid discharged into the EPDM hose 11 under pressure. The increase in volume is then compared with the initial internal volume of the EPDM hose 11 before pressurization. If the ratio of the two is greater than 8% (depending on the required expansion rate), the expansion rate of the EPDM hose 11 is deemed to be qualified. In addition to the above tests, the device can also perform pure gas pressure shock resistance tests. The specific operation is as follows: after removing the pressure test liquid, the EPDM hose 11 connected between the first quick connector 1d and the second quick connector 3c is periodically pressurized by the high-pressure gas source 5 in the form of pulse charging and discharging, so as to achieve compatibility between pressure test liquid pulse test and pure gas shock resistance test on the same hardware structure. S3. After the test is completed, open the drain valve 3b or the pressure relief valve 4b to release the residual pressure in the pipe, remove the EPDM hose 11 and transfer it to the precision testing station for final result testing.

[0028] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of the embodiments of the present invention.

Claims

1. A pressure detection device for automotive pipelines, characterized in that, include: A vertical container (1) has a closed pressure chamber inside, and a pressure measuring liquid is provided in the pressure chamber. The bottom of the vertical container (1) is provided with a first quick connector (1d) that connects to the pressure chamber. The first quick connector (1d) is used to connect one end of an EPDM hose (11). The first three-way connector (3) is fixedly installed on the side of the vertical container (1). The first three-way connector (3) forms a pressure balance interface (3a) and a drain valve (3b) at its two ends in the horizontal direction, respectively. The first three-way connector (3) forms a second quick connector (3c) at its bottom for connecting the other end of the EPDM hose (11). The pressure balance interface (3a), the drain valve (3b), and the second quick connector (3c) together constitute a three-way structure. The second three-way connector (4) is fixedly installed on the top of the vertical container (1). The bottom of the second three-way connector (4) is connected to the pressure chamber. The second three-way connector (4) has an inflation port (4a) and a pressure relief valve (4b) at its two ends in the horizontal direction. The inflation port (4a), the pressure relief valve (4b) and the bottom of the second three-way connector (4) together form a three-way structure. A high-pressure air source (5) is connected to the air filling port (4a) through a diversion valve (6), and the air pressure balance port (3a) is connected to the diversion valve (6) through a connecting pipe (7).

2. The air pressure detection device for automotive pipelines according to claim 1, characterized in that, An aluminum profile support column (2) is fixedly installed on the side of the vertical container (1). The aluminum profile support column (2) is parallel to the vertical container (1). The first tee connector (3) is fixedly connected to the aluminum profile support column (2) by fasteners (8) so that the vertical height of the first tee connector (3) is adjustable.

3. The air pressure detection device for automotive pipelines according to claim 1, characterized in that, The bottom of the vertical container (1) is also provided with a liquid injection port (1e) that communicates with the pressure chamber, and the liquid injection port (1e) is provided with an on / off valve (1a).

4. The air pressure detection device for automotive pipelines according to claim 3, characterized in that, The on / off valve (1a) is connected to a hose (9), and the other end of the hose (9) is connected to a graduated cylinder piston injector (10).

5. The air pressure detection device for automotive pipelines according to claim 1, characterized in that, A vertically extending transparent window (1b) is formed on the vertical container (1), and a liquid level scale is formed on the transparent window (1b).

6. The air pressure detection device for automotive pipelines according to claim 1, characterized in that, Both the relief valve (3b) and the pressure relief valve (4b) are manual valves or solenoid valves.

7. The air pressure detection device for automotive pipelines according to claim 3, characterized in that, The on / off valve (1a) is a manual valve.

8. The air pressure detection device for automotive pipelines according to claim 1, characterized in that, It also includes a control module, which is used to control the high-pressure gas source (5) to output pulsed air pressure with a set frequency and a set pressure to the inflation port (4a) and the air pressure balance port (3a).

9. The air pressure detection device for automotive pipelines according to claim 8, characterized in that, The vertical container (1) is equipped with a liquid level sensor, which is connected to the control module for real-time acquisition of the liquid level height data of the pressure measuring liquid in the pressure chamber and sending it to the control module.

10. A method for detecting pressure in automotive pipelines, comprising the apparatus as described in claim 1, characterized in that, The detection method includes the following steps: S1, connect the two ends of the EPDM hose (11) to the first quick connector (1d) and the second quick connector (3c) respectively, so that it forms a U-shaped connecting pipe structure with the vertical container (1); Open the drain valve (3b) and the pressure relief valve (4b) to allow the pressure-measuring liquid in the vertical container (1) to flow into the EPDM hose (11), and wait for the liquid level in the EPDM hose (11) to be consistent with the liquid level in the vertical container (1) under atmospheric pressure; S2, close the drain valve (3b) and the pressure relief valve (4b), open the high-pressure gas source (5), so that the gas enters the liquid above the pressure chamber and the first three-way connector (3) respectively after passing through the diversion valve (6); The high-pressure gas source (5) is controlled to periodically pressurize in the form of pulsed gas pressure. During this process, the drop in the liquid level of the pressure measuring liquid in the vertical container (1) is recorded, and the expansion rate of the EPDM hose (11) is judged accordingly. S3. After the test is completed, open the drain valve (3b) or the pressure relief valve (4b) to release the residual pressure in the pipe, remove the EPDM hose (11) and transfer it to the precision testing station for final result testing.

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