A pressure gauge pressure fatigue testing device

Abstract

This utility model relates to the field of pressure gauge testing technology, specifically to a pressure gauge pressure fatigue testing device, including a piston cylinder with a piston slidingly mounted inside. One end of the piston cylinder is connected to a vent pipe, and multiple branch pipes are connected in parallel on the vent pipe. One branch pipe is used to connect and install a standard pressure gauge, and the other branch pipes are used to connect and install the pressure gauge to be tested. The other end of the piston cylinder has a through hole. A servo cylinder has its telescopic end moving through the through hole into the piston cylinder, and its telescopic end is fixedly connected to the piston. A booster pump is connected to the inside of the piston cylinder through an air inlet pipe, which is equipped with a high-pressure valve. The servo motor is set with corresponding operating parameters to drive the piston to move at a constant speed, changing the size of the sealed space formed by the piston and the piston cylinder, controlling the pressure change inside the piston cylinder, and thus accurately controlling the pressure inside the piston cylinder, enabling precise control of the pressure on the pressure gauge.

Description

Technical Field

[0001] This utility model relates to the field of pressure gauge testing technology, specifically to a pressure gauge pressure fatigue testing device. Background Technology

[0002] According to national standards and metrological regulations such as GB / T 1226-2017 General Pressure Gauges and JJG 52-2013 Elastic Element Type General Pressure Gauges, Pressure Vacuum Gauges and Vacuum Gauges, pressure gauges must pass a pressure resistance test (usually 1.5 times the rated range for 3 minutes) and a fatigue test (usually 0 to 0.8 times the rated range for more than 10,000 cycles) before leaving the factory or during periodic calibration to verify their structural strength, the absence of cracks in the casing and joints, the absence of media leakage in the sealing performance, and the absence of permanent drift in the indication.

[0003] When conducting pressure fatigue tests on pressure gauges, a pressure gauge pressure fatigue testing device is required. The working principle of the existing pressure gauge pressure fatigue testing device is as follows: compressed gas or hydraulic oil is generated by a pressure generating unit such as an air compressor or hydraulic pump station as a pressure medium. The pressure control unit such as a solenoid valve, relay or simple PLC adjusts the medium pressure. Then, the pressure is transmitted to the pressure gauge under test through a connection unit such as a multi-position connector or medium pipeline, and finally the pressure holding or fatigue cycle test is completed.

[0004] However, in existing pressure gauge fatigue testing devices, during the overpressure phase of the pressure test, when the pressure generating unit adjusts the rated pressure range, the valve opening and closing response has a delay of 0.5 to 2 seconds. This can easily lead to actual pressure overshoot (e.g., a setting of 15 MPa may result in an actual pressure of 15.8 MPa) or undershoot (e.g., only 14.2 MPa), exceeding the standard allowable pressure deviation range of ±1%. During the cyclic phase of the fatigue test, due to the poor stability of the output pressure of the pressure generating unit (e.g., air compressor supply pressure fluctuations of ±0.3 MPa), and the inability of the control unit to compensate for pressure loss in real time, the actual deviation between the pressure peak and valley values ​​in a single cycle can reach ±5% of the rated range. This fails to simulate the smooth pressure fluctuation process under real working conditions, ultimately resulting in the pressure on the pressure gauge being unable to be precisely controlled as needed during the pressure fatigue test, thus easily affecting the accuracy of the test results. Utility Model Content

[0005] The purpose of this invention is to provide a pressure gauge pressure fatigue testing device, which solves the problem that in the existing pressure gauge pressure fatigue testing device, the pressure on the pressure gauge cannot be precisely controlled as needed during the pressure fatigue test, thus easily affecting the accuracy of the test results.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] A pressure gauge pressure fatigue test device includes a piston cylinder, a piston is slidably mounted inside the piston cylinder, one end of the piston cylinder is connected to a vent pipe, and multiple branch pipes are connected in parallel on the vent pipe. One branch pipe is used to connect and install a standard pressure gauge, and the other branch pipes are used to connect and install the pressure gauge to be tested. The other end of the piston cylinder has a through hole along its central axis that communicates with its interior.

[0008] The servo cylinder has its telescopic end inserted into the piston cylinder through a through hole and positioned towards the central axis of the piston cylinder, with the end of its telescopic end fixedly connected to the piston.

[0009] And a booster pump, which is connected to the piston cylinder through an intake pipe and has a high-pressure valve.

[0010] A further technical solution is that the standard pressure gauge and the pressure gauge to be tested are connected to the branch pipe through an adapter. The bottom end of the adapter is inserted into the top end of the branch pipe. The top side of the adapter is provided with a connector that is compatible with the connection end of the standard pressure gauge and the pressure gauge to be tested. A sealing ring is provided on the inner wall of the top end of the branch pipe. The inner diameter of the sealing ring increases from top to bottom. A locking component is provided between the adapter and the branch pipe.

[0011] A further technical solution is that the locking component includes a U-shaped buckle, and a connecting block is symmetrically protruding on the outer side of the branch pipe. The connecting block is rotatably connected to the open end of the U-shaped buckle, and a buckle block that is adapted to the U-shaped buckle is symmetrically protruding on the outer side of the adapter.

[0012] A further technical solution is to provide an abutment ring on the outer side of the adapter and a sealing ring on the top side of the branch pipe.

[0013] A further technical solution includes a control console, which is electrically connected to the servo cylinder and used to control the operation of the servo cylinder.

[0014] Compared with the prior art, the beneficial effects of this utility model are:

[0015] In use, this invention involves installing a standard pressure gauge and a corresponding pressure gauge to be tested on a branch pipe. A booster pump then pressurizes the piston cylinder. The pressure inside the piston cylinder can be monitored in real-time by observing the standard pressure gauge. When the pressure inside the piston cylinder approaches the rated pressure of the pressure gauge to be tested, the booster pump stops working and the high-pressure valve is closed. Then, the extension and retraction of the servo cylinder's telescopic end is controlled, causing the piston to move and correcting the size of the sealed space inside the piston cylinder. This compresses the internal medium and adjusts the pressure inside the piston cylinder. The pressure values ​​detected by the standard and pressure gauges will change accordingly with the pressure changes inside the piston cylinder. Because the servo motor can be set with appropriate operating parameters to drive the piston at a constant speed, changing the size of the sealed space formed by the piston and piston cylinder, and controlling the pressure changes inside the piston cylinder, the pressure inside the piston cylinder can be precisely controlled. This allows for accurate control of the pressure on the pressure gauge, ensuring the accuracy of the test results. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the pressure gauge pressure fatigue testing device of this utility model.

[0017] Figure 2 This is a schematic diagram of the disassembled cross-sectional structure of the branch pipe and adapter of this utility model.

[0018] Icons: 1-Piston cylinder, 2-Piston, 3-Ventilation pipe, 4-Branch pipe, 5-Standard pressure gauge, 6-Pressure gauge to be measured, 7-Through hole, 8-Servo cylinder, 9-Boost pump, 10-Inlet pipe, 11-High pressure valve, 12-Adapter, 13-Connector, 14-Sealing ring, 15-U-shaped retaining ring, 16-Connecting block, 17-Retaining block, 18-Abutment ring, 19-Sealing ring. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0020] Example 1

[0021] Reference Figure 1 , Figure 2This utility model discloses a pressure gauge pressure fatigue testing device, including a piston cylinder 1, a piston 2 that slides inside the piston cylinder 1, a ventilation pipe 3 connected to one end of the piston cylinder 1, and multiple branch pipes 4 connected in parallel on the ventilation pipe 3. One branch pipe 4 is used to connect and install a standard pressure gauge 5, and the other branch pipes 4 are used to connect and install a pressure gauge 6 to be tested. The rated range of the standard pressure gauge 5 is greater than the rated range of the pressure gauge 6 to be tested. The other end of the piston cylinder 1 has a through hole 7 that communicates with its interior along its central axis.

[0022] Servo cylinder 8, the telescopic end of servo cylinder 8 is movably inserted into piston cylinder 1 through through hole 7 and is set towards the central axis of piston cylinder 1, and the end of its telescopic end is fixedly connected to piston 2.

[0023] And a booster pump 9, which is connected to the piston cylinder 1 via an intake pipe 10, and a high-pressure valve 11 is provided on the intake pipe 10.

[0024] In this embodiment, initially, the extension end of the servo cylinder 8 is partially extended, so that the piston 2 is in the middle position inside the piston cylinder 1. During use, a standard pressure gauge 5 and a corresponding pressure gauge 6 to be measured are installed on the branch pipe 4. Then, the booster pump 9 pressurizes the piston cylinder 1. The pressure inside the piston cylinder 1 can be monitored in real time by observing the standard pressure gauge 5. When the pressure inside the piston cylinder 1 approaches the rated pressure of the pressure gauge 6 to be measured, the booster pump 9 is stopped and the high-pressure valve 11 is closed. For example, if the rated pressure of the pressure gauge 6 to be measured is 10 MPa, that is, when the pressure inside the piston cylinder 1 is 9.5 MPa, the booster pump 9 is stopped and the high-pressure valve 11 is closed. Then, the extension end of the servo cylinder 8 is controlled to extend and retract, which can bring... The movement of piston 2 corrects the size of the sealed space inside piston cylinder 1, compressing the internal medium and adjusting the pressure inside piston cylinder 1. At this time, the pressure values ​​detected by the standard pressure gauge 5 and the pressure gauge under test 6 will change with the pressure change inside piston cylinder 1, thus testing the pressure gauge under test 6. At the same time, the pressure values ​​monitored by the pressure gauge under test 6 and the standard pressure gauge 5 can be compared to determine whether the pressure gauge under test 6 is working properly. Since the corresponding working parameters can be set for the servo cylinder 8, driving piston 2 to move at a constant speed changes the size of the sealed space formed by piston 2 and piston cylinder 1, controlling the pressure change inside piston cylinder 1. This allows for precise control of the pressure inside piston cylinder 1, enabling accurate control of the pressure on the pressure gauge and ensuring the accuracy of the test results.

[0025] For example, when conducting a pressure resistance test on the pressure gauge 6 under test, the working parameters of the servo cylinder 8 can be set to a single reciprocating motion: extension stage → dwell stage (dwell time ≥ 3 minutes) → retraction stage. Specifically, the extension stage causes the extension end of the servo cylinder 8 to drive the piston 2 to move relative to the piston cylinder 1, reducing the sealing space formed by the piston 2 and the piston cylinder 1, thereby increasing the pressure inside the piston cylinder 1. After the extension stage is completed, the pressure inside the piston cylinder 1 meets the test pressure of the corresponding pressure gauge 6 under test. The dwell stage is set according to the pressure holding time of the pressure gauge 6 under test. After the pressure holding time is reached, the retraction stage is achieved by the extension end of the servo cylinder 8 driving the piston 2 to move relative to the piston cylinder 1 to reset, so as to facilitate the subsequent pressure resistance test on the pressure gauge 6 under test. The actual extension length of the extension end of the servo cylinder 8 during the extension stage can be determined through multiple experiments on the corresponding pressure gauge 6 under test, thereby proving that the actual extension length of the extension end of the servo cylinder 8 during the extension stage ensures that the pressure inside the piston cylinder 1 meets the test pressure.

[0026] When conducting fatigue tests on the pressure gauge 6, the operating parameters of the servo cylinder 8 can be set to a reciprocating cycle: retraction phase → extension and reset phase → extension phase → retraction and return phase → repeat phase. Specifically, the retraction phase moves the piston 2, increasing the sealing space between the piston 2 and the piston cylinder 1, thereby reducing the pressure inside the piston cylinder 1. The extension and reset phases and the extension phase move the piston 2, reducing the sealing space between the piston 2 and the piston cylinder 1, thus increasing the pressure inside the piston cylinder 1. The retraction and return phase, in conjunction with the retraction phase in the subsequent repeat phase, moves the piston 2, increasing the sealing space between the piston 2 and the piston cylinder 1. The increased sealing space reduces the pressure inside piston cylinder 1. By repeating the above cyclic working parameters, the pressure range inside piston cylinder 1 can be adjusted, providing the cyclic pressure range and number of cycles for fatigue testing. Simultaneously, servo cylinder 8 drives piston 2 to move uniformly, thus uniformly changing the pressure rise and fall inside piston cylinder 1 and avoiding instantaneous pressure shocks. The actual extension length of the extension end of servo cylinder 8 during the extension phase can be determined through multiple experiments using the corresponding pressure gauge 6 to be tested, thereby proving that the actual extension length of the extension end of servo cylinder 8 during the extension phase ensures that the pressure inside piston cylinder 1 meets the test pressure.

[0027] Example 2

[0028] Based on Example 1, referring to Figure 1 , Figure 2The standard pressure gauge 5 and the pressure gauge to be tested 6 are connected to the branch pipe 4 via an adapter 12. The bottom end of the adapter 12 is inserted into the top end of the branch pipe 4. The top side of the adapter 12 is provided with a connector 13 that is compatible with the connection ends of the standard pressure gauge 5 and the pressure gauge to be tested 6. A sealing ring 14 is provided on the inner side wall of the top end of the branch pipe 4. The inner ring diameter of the sealing ring 14 increases from top to bottom. The inner ring diameter at the bottom end of the sealing ring 14 is smaller than the outer ring diameter at the bottom end of the adapter 12, and the inner ring diameter at the top end of the sealing ring 14 is larger than the outer ring diameter at the bottom end of the adapter 12. A locking component is provided between the adapter 12 and the branch pipe 4.

[0029] In this embodiment, the connecting ends of the pressure gauge 6 to be tested and the standard pressure gauge 5 are connected to the connector 13. Then, the bottom end of the adapter 12 is inserted into the top end of the branch pipe 4. At this time, the inner ring wall of the sealing ring 14 is in close contact with the outer side of the bottom end of the adapter 12, thereby playing a corresponding sealing role. The adapter 12 is then fixed by the locking component. By setting the adapter 12, it is easy to quickly install the pressure gauge 6 to be tested on the branch pipe 4. At the same time, multiple adapters 12 can be adapted. When the previous batch of pressure gauges 6 to be tested is tested, the loading worker can install the next batch of pressure gauges 6 to be tested on the adapter 12, so that the next batch of pressure gauges 6 to be tested can be quickly installed on the branch pipe 4 through the adapter 12, thereby improving work efficiency.

[0030] As a preferred implementation method, refer to Figure 1 , Figure 2 The locking assembly includes a U-shaped buckle 15, and connecting blocks 16 are symmetrically protruding on the outer side of the branch pipe 4. The connecting blocks 16 are rotatably connected to the open end of the U-shaped buckle 15. A buckle block 17, adapted to the U-shaped buckle 15, is symmetrically protruding on the outer side of the adapter 12. Specifically, when the bottom end of the adapter 12 is inserted into the top end of the branch pipe 4, rotating the U-shaped buckle 15 causes the closed end of the buckle to engage with the buckle block 17, thereby holding the adapter 12 in place and preventing the bottom end of the adapter 12 from sliding upwards out of the top end of the branch pipe 4. As a preferred embodiment, refer to... Figure 1 An abutment ring 18 is fitted on the outer side of the adapter 12, and a sealing ring 19 is provided around the top side of the branch pipe 4. Specifically, when the bottom end of the adapter 12 is inserted into the inside of the top end of the branch pipe 4, the abutment ring 18 and the sealing ring 19 come into close contact, thereby ensuring the sealing of the connection between the adapter 12 and the branch pipe 4.

[0031] Example 3

[0032] Based on Embodiment 1, a control console (not shown in the diagram) is also included. The control console is electrically connected to the servo cylinder 8 and is used to control the operation of the servo cylinder 8. Specifically, the commands from the control console are transmitted to the servo cylinder 8 through signal lines (such as RS485 or PROFINET bus). At the same time, the control console and the servo cylinder 8 use a matching signal protocol (such as Modbus or PROFINET industrial bus commonly used by PLCs) to avoid signal transmission deviation.

[0033] Although the present invention has been described herein with reference to several illustrative embodiments, it should be understood that many other modifications and implementations can be devised by those skilled in the art, which will fall within the scope and spirit of the principles disclosed herein. More specifically, various variations and modifications can be made to the components and / or layout of the subject matter combination within the scope of the disclosure, drawings, and claims. Besides variations and modifications to the components and / or layout, other uses will be apparent to those skilled in the art.

Claims

1. A pressure gauge pressure fatigue test device characterized by comprising: Includes a piston cylinder (1), inside which a piston (2) is slidably mounted, one end of which is connected to a vent pipe (3), and multiple branch pipes (4) are connected in parallel on the vent pipe (3), one of which is used to connect and install a standard pressure gauge (5), and the other branch pipes (4) are used to connect and install a pressure gauge to be tested (6), and the other end of the piston cylinder (1) has a through hole (7) connected to its interior along its central axis; Servo cylinder (8), the telescopic end of the servo cylinder (8) is movably inserted into the piston cylinder (1) through the through hole (7) and is set in the direction of the central axis of the piston cylinder (1), and the end of its telescopic end is fixedly connected to the piston (2). And a booster pump (9), which is connected to the piston cylinder (1) via an air intake pipe (10), and a high-pressure valve (11) is provided on the air intake pipe (10).

2. The pressure fatigue testing device for a pressure gauge according to claim 1, characterized by: The standard pressure gauge (5) and the pressure gauge to be tested (6) are connected to the branch pipe (4) through an adapter (12). The bottom end of the adapter (12) is inserted into the top end of the branch pipe (4). The top side of the adapter (12) is provided with a connector (13) that is compatible with the connection end of the standard pressure gauge (5) and the pressure gauge to be tested (6). A sealing ring (14) is provided on the inner side wall of the top end of the branch pipe (4). The inner ring diameter of the sealing ring (14) increases from top to bottom. A locking component is provided between the adapter (12) and the branch pipe (4).

3. The pressure fatigue testing apparatus of claim 2, wherein: The locking assembly includes a U-shaped buckle (15), and a connecting block (16) is symmetrically protruding on the outer side of the branch pipe (4). The connecting block (16) is rotatably connected to the open end of the U-shaped buckle (15), and a buckle block (17) that is adapted to the U-shaped buckle (15) is symmetrically protruding on the outer side of the adapter (12).

4. The pressure fatigue testing apparatus of claim 3, wherein: An abutment ring (18) is fitted on the outer side of the adapter (12), and a sealing ring (19) is provided around the top side of the branch pipe (4).

5. The pressure fatigue testing apparatus of claim 1, wherein: It also includes a console, which is electrically connected to the servo cylinder (8) and is used to control the operation of the servo cylinder (8).

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