A pressure gauge testing device

Abstract

The present invention relates to a pressure gauge testing device, comprising an air source and a cylinder connected by an air circuit, wherein an electromagnetic valve is installed on the air circuit for controlling the bidirectional movement of a piston in the cylinder; further comprising a first pipeline, a test sample and a booster cylinder, wherein a center hole is opened on the booster cylinder, and the extended end of the piston rod of the cylinder is slidably inserted into one end of the booster cylinder, and the other end of the booster cylinder is connected to one end of the first pipeline, and a valve is installed on the other end of the first pipeline; the test sample is installed on the side wall of the first pipeline and is connected to its inner cavity. Compared with the prior art, the present invention can perform both static pressure fatigue test and dynamic pressure fatigue test on the pressure gauge sample, thereby improving the reliability of the product.

Description

Technical Field

[0001] The invention relates to the technical field of instrument testing, and in particular to a pressure gauge testing device. Background Art

[0002] A pressure gauge is an instrument that uses elastic elements as sensitive elements to measure and indicate pressures higher than the ambient pressure. It is widely used in almost all industrial processes and scientific research fields. In order to avoid fatigue damage during use, the pressure gauge samples need to be fatigue tested before leaving the factory. In the prior art, when testing a pressure gauge sample, the test device passes high-pressure liquid into the test sample and maintains the pressure for a period of time to monitor whether the test sample will be fatigued and damaged under continuous high-pressure use conditions. The test device in the prior art can only perform the aforementioned static pressure test on the pressure gauge sample, and cannot test whether the pressure gauge sample will be fatigued and damaged when facing a use scenario with continuously changing pressure. That is, it is impossible to perform dynamic pressure fatigue testing, resulting in low product reliability. Summary of the invention

[0003] The purpose of the present invention is to provide a pressure gauge testing device to address the problem that the testing device in the prior art can only perform static pressure fatigue test on pressure gauge samples but cannot perform dynamic pressure fatigue test, resulting in low product reliability.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A pressure gauge testing device comprises an air source and an air cylinder connected by an air circuit, wherein an electromagnetic valve is installed on the air circuit for controlling the bidirectional movement of a piston in the air cylinder; further comprising a first pipeline, a test sample and a booster cylinder, wherein a center hole is provided on the booster cylinder, the extended end of the piston rod of the cylinder is slidably inserted into one end of the booster cylinder, the other end of the booster cylinder is communicated with one end of the first pipeline, and a valve is installed on the other end of the first pipeline; the test sample is installed on the side wall of the first pipeline and communicated with its inner cavity.

[0006] The present invention adopts the above-mentioned technical scheme. When performing fatigue test, the valve is first opened to fill the first pipeline and the booster cylinder with liquid medium for transmitting pressure. After the liquid medium in the first pipeline reaches a predetermined pressure, the valve is closed. At this time, the pressure test sample tests the pressure of the liquid medium in the first pipeline; then, the solenoid valve controls the movement of the piston in the cylinder, drives the extended end of the piston rod to slide in the booster cylinder, changes the volume of the internal space of the booster cylinder, and thus changes the pressure of the liquid medium; when performing static pressure test, the solenoid valve controls the movement of the piston until the pressure of the liquid medium in the first pipeline reaches the static pressure test pressure, closes the solenoid valve, stops the movement of the piston, and the pressure of the liquid medium is constant; when performing dynamic pressure test, the solenoid valve controls the reciprocating cyclic movement of the piston, so that the pressure of the liquid medium in the first pipeline changes cyclically within a set range; compared with the test device in the prior art that can only perform static pressure fatigue test on the pressure gauge sample but cannot perform dynamic pressure fatigue test, resulting in the problem of low product reliability, the present invention can perform both static pressure fatigue test and dynamic pressure fatigue test on the pressure gauge sample, thereby improving the reliability of the product.

[0007] Furthermore, the booster cylinder includes a cylinder barrel and an end plate arranged at one end of the cylinder barrel, the extended end of the piston rod is slidably inserted in the cylinder barrel, a through hole is provided on the end plate, one end of the first pipe is fixed on the end plate and connected to the through hole; the inner diameter of the cylinder barrel is larger than the inner diameter of the first pipe.

[0008] Furthermore, the first pipeline is provided with a first branch pipe, and a pressure sensor is installed at the end of the first branch pipe; it also includes a controller, and the pressure sensor and the solenoid valve are electrically connected to the controller respectively; the pressure sensor is used to monitor the pressure of the liquid medium and transmit it to the controller, and the controller transmits instructions to the solenoid valve based on the pressure data to control the movement of the piston in the cylinder to adjust the pressure of the liquid medium.

[0009] Furthermore, it also includes a second pipeline, an electric pump and a water tank; the valve is a one-way valve, the water outlet of which is connected to the first pipeline, and the water inlet of which is connected to the water tank through the second pipeline; the electric pump is installed on the second pipeline; the electric pump is used to extract liquid medium from the water tank, and injects it into the first pipeline after passing through the one-way valve. After the liquid medium reaches a predetermined pressure, the electric pump is turned off, and the one-way valve is closed at this time, and the liquid medium will not flow back.

[0010] Furthermore, a second branch pipe connected to the water tank is provided on the first pipeline, and a pressure relief valve is installed on the second branch pipe; after the test is completed, the pressure relief valve is opened, and the liquid medium can flow back into the water tank from the second branch pipe.

[0011] Furthermore, a pressure reducing valve is provided on the gas path between the gas source and the solenoid valve; the pressure reducing valve is used to adjust the intake pressure so that the liquid pressure value in the first pipeline can meet the static pressure and dynamic pressure tests. At the same time, the pressure reducing valve can keep the intake pressure stable, which is beneficial to the stability of the testing device.

[0012] Furthermore, a sealing ring is provided on the inner wall of the booster cylinder, and the piston rod passes through the sealing ring and forms a seal with the booster cylinder to prevent water leakage between the piston rod and the booster cylinder, thereby affecting the test accuracy.

[0013] The beneficial effects of the present invention are: both static pressure fatigue test and dynamic pressure fatigue test can be performed on the pressure gauge sample, thereby improving the reliability of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the present invention.

[0015] Markings in the figure: 1-cylinder, 2-piston rod, 3-sealing ring, 4-boosting cylinder, 5-test sample, 6-pressure sensor, 7-pressure relief valve, 8-check valve, 9-electric pump, 10-water tank, 11-controller, 12-solenoid valve, 13-pressure reducing valve, 14-first pipeline, 15-second pipeline, 16-first air pipe, 17-second air pipe, 18-third air pipe, 19-first branch pipe, 20-second branch pipe. DETAILED DESCRIPTION

[0016] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0017] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0018] The embodiment of the present invention provides a pressure gauge testing device, such as Figure 1 As shown, it includes an air source and a cylinder 1 connected by an air circuit, and a solenoid valve 12 is installed on the air circuit to control the bidirectional movement of the piston in the cylinder 1; it also includes a first pipeline 14, a test sample 5 and a hollow booster cylinder 4, the extended end of the piston rod 2 of the cylinder 1 is slidably plugged into one end of the booster cylinder 4, the other end of the booster cylinder 4 is connected to one end of the first pipeline 14, and a valve is installed on the other end of the first pipeline 14; the test sample 5 is installed on the side wall of the first pipeline 14 and is connected to its inner cavity;

[0019] Specifically, the gas source is an air compressor, the solenoid valve 12 is a two-position five-way solenoid valve, the gas circuit includes a first gas pipe 16, a second gas pipe 17 and a third gas pipe 18, the first gas pipe 16 is connected between the gas source and the solenoid valve 12, the second gas pipe 17 and the third gas pipe 18 are both connected between the solenoid valve 12 and the cylinder 1, and the ends of the second gas pipe 17 and the third gas pipe 18 away from the cylinder 1 are respectively connected to the two ends of the cylinder 1; the two-position five-way solenoid valve drives the piston to move in both directions by changing the direction of the intake air flow, and the specific structure and principle are prior art, which will not be repeated here; the number of test samples 5 can be multiple, and they are arranged at intervals along the length direction of the first pipeline 14;

[0020] The booster cylinder 4 includes a cylinder barrel and an end plate provided at one end of the cylinder barrel. The extended end of the piston rod 2 is slidably inserted in the cylinder barrel. A through hole is provided on the end plate. One end of the first pipe 14 is fixed on the end plate and communicated with the through hole. The inner diameter of the cylinder barrel is larger than the inner diameter of the first pipe 14.

[0021] The first pipeline 14 is provided with a first branch pipe 19, and a pressure sensor 6 is installed at the end of the first branch pipe 19; the controller 11 is also included, and the pressure sensor 6 and the solenoid valve 12 are electrically connected to the controller 11 respectively;

[0022] It also includes a second pipeline 15, an electric pump 9 and a water tank 10; the valve is a one-way valve 8, the water outlet of which is connected to the first pipeline 14, and the water inlet of which is connected to the water tank 10 through the second pipeline 15; the electric pump 9 is installed on the second pipeline 15; the electric pump 9 is electrically connected to the controller 11;

[0023] The first pipeline 14 is provided with a second branch pipe 20 connected to the water tank 10, and a pressure relief valve 7 is installed on the second branch pipe 20; the pressure relief valve 7 is a manual pressure relief valve;

[0024] A pressure reducing valve 13 is provided on the gas path between the gas source and the solenoid valve 12;

[0025] A sealing ring 3 is provided on the inner wall of the boosting cylinder 4 , and the piston rod 2 passes through the sealing ring 3 and forms a seal with the boosting cylinder 4 .

[0026] During the test, the steps are as follows:

[0027] 1) Install the pressure test sample 5 to be tested on the first pipeline 14 and manually close the pressure relief valve 7;

[0028] 2) Operate the controller 11, start the electric pump 9, and pump the water in the water tank 10 into the first pipe 14 and the booster cylinder 4; when the pressure sensor 6 detects that the pressure of the water in the first pipe 14 reaches the set value, the controller 11 turns off the electric pump 9; at this time, the one-way valve 8 is in a closed state, and the initial pressure of the first pipe 14 is stable;

[0029] 3) Debug the pressure reducing valve 13 so that the airflow after the pressure reduction through the pressure reducing valve 13 pushes the piston to move until the pressure measured by the pressure sensor 6 can reach the pressure value during the static pressure test (the static pressure test pressure value is greater than the upper limit of the dynamic pressure test pressure value, so as long as the air pressure after the pressure reduction through the pressure reducing valve 13 can meet the static pressure test, it must meet the dynamic pressure test). After the debugging is completed, the pressure reducing valve 13 is no longer adjusted;

[0030] 4) If a static pressure test is performed, the solenoid valve 12 controls the piston to move unidirectionally until the pressure measured by the pressure sensor 6 reaches the static pressure test pressure value. At this time, the controller controls the solenoid valve 12 to close, the piston stops moving, and the pressure tested on the test sample 5 is constant; if a dynamic pressure test is performed, the solenoid valve 12 controls the piston to move unidirectionally until the pressure measured by the pressure sensor 6 reaches the upper limit value of the dynamic pressure test pressure. At this time, the controller controls the solenoid valve 12 to change the gas flow direction in the gas circuit, and the piston moves in the opposite direction until the pressure measured by the pressure sensor 6 reaches the lower limit value of the dynamic pressure test pressure. At this time, the controller controls the solenoid valve 12 to change the gas flow direction in the gas circuit, and the piston moves in the opposite direction again, and this cycle is repeated, so that the test sample 5 is tested with alternating pressure.

[0031] 5) After the test is completed, the pressure relief valve 7 is opened manually, and the water in the first pipe 14 flows back into the water tank 10 from the second branch pipe 20.

[0032] The present invention adopting the above-mentioned technical scheme is compared with the testing device in the prior art which can only perform static pressure fatigue test on the pressure gauge sample but cannot perform dynamic pressure fatigue test, resulting in the problem of low product reliability. The present invention adopting the above-mentioned technical scheme can perform both static pressure fatigue test and dynamic pressure fatigue test on the pressure gauge sample, thereby improving the reliability of the product.

[0033] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A pressure gauge testing device, characterized in that: It comprises an air source and an air cylinder (1) connected by an air circuit, wherein the air circuit is provided with an electromagnetic valve (12) for controlling the bidirectional movement of a piston in the air cylinder (1); it also comprises a first pipe (14), a test sample (5) and a booster cylinder (4), wherein the booster cylinder (4) is provided with a central hole, the extended end of the piston rod (2) of the air cylinder (1) is slidably plugged into one end of the booster cylinder (4), the other end of the booster cylinder (4) is communicated with one end of the first pipe (14), and the other end of the first pipe (14) is provided with a valve; the test sample (5) is installed on the side wall of the first pipe (14) and is communicated with its inner cavity; The first pipeline (14) is provided with a first branch pipe (19), and a pressure sensor (6) is installed at the end of the first branch pipe (19); and the device further comprises a controller (11), and the pressure sensor (6) and the solenoid valve (12) are respectively electrically connected to the controller (11); It also comprises a second pipeline (15), an electric pump (9) and a water tank (10); the valve is a one-way valve (8), the water outlet of which is connected to the first pipeline (14), and the water inlet of which is connected to the water tank (10) through the second pipeline (15); the electric pump (9) is installed on the second pipeline (15); The first pipeline (14) is provided with a second branch pipe (20) connected to the water tank (10), and the second branch pipe (20) is installed with a pressure relief valve (7); A pressure reducing valve (13) is provided on the gas path between the gas source and the solenoid valve (12); A sealing ring (3) is provided on the inner wall of the boosting cylinder (4), and the piston rod (2) passes through the sealing ring (3) and forms a seal with the boosting cylinder (4).

2. The pressure gauge testing device according to claim 1, characterized in that: The booster cylinder (4) comprises a cylinder barrel and an end plate arranged at one end of the cylinder barrel, the extended end of the piston rod (2) is slidably inserted into the cylinder barrel, a through hole is provided on the end plate, one end of the first pipe (14) is fixed on the end plate and communicates with the through hole; the inner diameter of the cylinder barrel is larger than the inner diameter of the first pipe (14).

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