Hydraulic testing device

Abstract

A water pressure testing device, a clamping mechanism for clamping the product to be tested is installed on the workbench, a water pump is used to pump water in the water tank into the sealed pressure tank, an air pump is used to supply pressurized air to the sealed pressure tank, a first valve is arranged on the air path between the air outlet of the air pump and the air inlet of the sealed pressure tank, a second valve is arranged on the water path between the water outlet of the water tank and the water inlet of the sealed pressure tank, a third valve is arranged on the air path between the air outlet of the sealed pressure tank and the air inlet of the product to be tested, a fourth valve is arranged on the water path between the water outlet of the sealed pressure tank and the water inlet of the product to be tested, and a fifth valve is arranged on the water path between the water outlet of the product to be tested and the water tank. The water pressure testing device pressurizes the inside of the product to be tested with the air pump, the pressurization speed is faster, there is almost no loss of test water during the pressurization process, and the air pressure during pressurization is used for pressure relief and drainage, avoiding the need for additional equipment to depressurize the sealed pressure tank, and the structure is simple and reasonable.

Description

Technical Field

[0001] This utility model relates to a water pressure testing device. Background Technology

[0002] Explosion-proof acoustic and visual detectors are widely used in the security field. Because their internal casing needs to be isolated from the external environment during operation, their airtightness must be tested. Existing airtightness testing devices for explosion-proof acoustic and visual detectors typically use a hydrostatic test, which involves injecting water into the product under test and maintaining pressure. The main drawback of existing hydrostatic testing devices is their poor versatility. Testing different products requires changing not only the fixture module but also the overall frame of the testing device. Furthermore, they lack a pressure-holding function; if air is not purged from the product before pressure holding, the test results will be inaccurate if pressure drops before successful pressure holding. As an improvement, Chinese utility model patent No. 202221411865.3 (authorization announcement No. CN 217765407 U) discloses a "hydraulic pressure testing device". The hydraulic pressure testing device includes a frame, a workbench, a water tank, a water pump, a first connector clamp, a second connector clamp, a first drive member, a second drive member, and a third drive member. The workbench is provided with a workpiece detection station. The water tank inlet is connected to the second connector clamp, the water tank outlet is connected to the water pump inlet, and the water pump outlet is connected to the first connector clamp. Under the drive of the first and second drive members, the first and second connector clamps can clamp the workpiece to be tested on the workpiece detection station and communicate with it through the water storage cavity inside the workpiece. The third drive member is located above the workpiece detection station, and the drive output end of the third drive member can move down to seal with the top of the water storage cavity. This hydrostatic testing device can test porous and irregular products such as metal products by changing different connectors, clamps, and drive components. Furthermore, when testing similar products, only the first and second connectors need to be replaced. However, this device directly pressurizes the product under test using a water pump, resulting in water loss, inefficient water circulation, frequent water refills, and a relatively slow and expensive pump pressurization rate. The device also lacks a sealed pressurization tank, making it impossible to utilize the air pressure within the tank during depressurization. Additionally, the device uses left-right water inlet and outlet, potentially leaving residual test water inside the product. Therefore, further improvements to the existing hydrostatic testing device are necessary. Utility Model Content

[0003] The technical problem to be solved by this utility model is to provide a water pressure testing device that uses an air pump to increase pressure and makes reasonable use of the air pressure during the pressurization to release and drain water, in view of the above-mentioned existing technology.

[0004] The technical solution adopted by this utility model to solve the above-mentioned technical problem is as follows: a water pressure testing device, including a frame and a worktable disposed on the frame, wherein a clamping mechanism for clamping the product to be tested is installed on the worktable, characterized in that it further includes:

[0005] Water tank;

[0006] Sealed pressurized water tank;

[0007] A water pump is used to transport water from the water tank to the sealed pressurized water tank;

[0008] An air pump is used to supply pressurized air to a sealed pressurized water tank.

[0009] The first valve is located on the air path between the air pump outlet and the air inlet of the sealed pressurized water tank.

[0010] The second valve is located on the water line between the water tank outlet and the sealed pressurized water tank inlet.

[0011] The third valve is located in the air path between the air outlet of the sealed pressurized water tank and the air inlet of the product to be tested.

[0012] The fourth valve is located on the water line between the outlet of the sealed pressurized water tank and the inlet of the product to be tested.

[0013] The fifth valve is located on the water line between the drain outlet of the product under test and the water tank.

[0014] In order to control the water level in the sealed pressurized water tank, a water level sensor is installed in the sealed pressurized water tank. The water level sensor's sensing height is not higher than the height of the third valve and is higher than the height of the fourth valve. When the water level sensor is triggered, the water pump stops working.

[0015] A further preferred embodiment includes a pressure sensor, which is installed in the water path between the drain outlet of the product under test and the fifth valve, or in the air path between the third valve and the air inlet of the product under test, or in the water path between the fourth valve and the water inlet of the product under test. With this configuration, during pressure maintenance, the pressure sensor can detect whether the internal pressure of the product under test has decreased.

[0016] Further preferably, the water inlet of the product under test is located above the drain outlet. This configuration, with the product under test employing an upper water inlet and lower water outlet structure, allows for full utilization of the water's own gravity for drainage, preventing any residual test water inside the product.

[0017] Further preferably, the water pump is a pneumatic water pump. This configuration allows the water pump to blow air into the product during the pressure relief phase, expelling water droplets from the product's cavity walls.

[0018] The clamping mechanism can have various structures. This particular clamping mechanism includes a vertically arranged first driving member, a second driving member, and a horizontally arranged third driving member. The first driving member is positioned above the second driving member. In the testing state, the product to be tested is clamped between the first, second, and third driving members. This arrangement allows the product to be placed vertically, facilitating both top and bottom water inlet and outlet.

[0019] Further preferably, the first driving component is a first cylinder with its driving output end pointing vertically downwards; the second driving component is a second cylinder with its driving output end pointing vertically upwards; the third driving component is a third cylinder with its driving output end pointing horizontally; a first plug is installed at the driving output end of the first cylinder; a second plug is installed at the driving output end of the second cylinder; and a third plug is installed at the driving output end of the third cylinder; the product under test is clamped between the first plug, the second plug, and the third plug.

[0020] In order to drive the third cylinder to move horizontally, a drive mechanism for driving the third cylinder to move horizontally is installed below the worktable.

[0021] Further preferably, the first valve, the second valve, the third valve, the fourth valve, and the fifth valve are all solenoid valves.

[0022] To achieve intelligent control, an electrical control system is also included to control the working status of the water pump, air pump, first valve, second valve, third valve, fourth valve, and fifth valve.

[0023] Compared with the prior art, the advantages of this utility model are as follows: This water pressure testing device uses an air pump to pressurize the gas and transfer it to the water in the sealed pressurized water tank to pressurize the inside of the product under test. The pressurization speed is faster, the equipment price is lower, and there is almost no loss of test water during the pressurization process. The water circulation is reasonable and there is no need to add water frequently. During the depressurization and drainage process, the air pressure during pressurization can be used reasonably, avoiding the need to use other equipment to depressurize the sealed pressurized water tank. The structure is simpler and more reasonable. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the water pressure testing device according to an embodiment of the present invention;

[0025] Figure 2 This is a front view of the water pressure testing device according to an embodiment of the present invention;

[0026] Figure 3 This is a schematic diagram of the component connections of the water pressure testing device according to an embodiment of the present invention;

[0027] Figure 4This is a schematic diagram of the upper and lower clamping parts according to an embodiment of the present utility model;

[0028] Figure 5 This is a schematic diagram of the structure of the third driving component according to an embodiment of the present utility model;

[0029] Figure 6 This is a schematic diagram of the solenoid valve status of the water pressure testing device according to an embodiment of this utility model. Detailed Implementation

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0031] like Figures 1 to 6 As shown, the water pressure testing device of this embodiment includes a frame 1 and a workbench 2 mounted on the frame 1. A clamping mechanism 3 for clamping the product 100 to be tested is installed on the workbench 2. The clamping mechanism 3 of this embodiment includes a vertically arranged first driving member, a second driving member, and a horizontally arranged third driving member. The first driving member is located above the second driving member. In the testing state, the product 100 to be tested is clamped between the first driving member, the second driving member, and the third driving member. Specifically, the first driving member is a first cylinder 31, and the driving output end of the first cylinder 31 is vertically downward. The second driving member is a second cylinder 32, and the driving output end of the second cylinder 32 is vertically upward. The third driving member is a third cylinder 33, and the driving output end of the third cylinder 33 is horizontally arranged. A first plug 311 is installed at the driving output end of the first cylinder 31, a second plug 321 is installed at the driving output end of the second cylinder 32, and a third plug 331 is installed at the driving output end of the third cylinder 33. A drive mechanism 11 is installed below the workbench 2 to drive the third cylinder 33 to move horizontally. During testing, the product to be tested 100 is clamped between the first plug 311, the second plug 321, and the third plug 331. In this embodiment, the first cylinder 31 and the second cylinder 32, i.e., the upper and lower clamping cylinders, are standard adjustable stroke cylinders with a cylinder diameter of 40mm. The theoretical output force is not less than 80 kg when the input air pressure is 0.8 MPa, and the stroke length is 125 mm. The third cylinder 33, i.e., the side clamping cylinder, is a pneumatic-hydraulic booster cylinder, model MPT63x150-20-1T. With suitable seals, it is completely sufficient for sealing. The model of the above cylinders can be changed according to the actual situation.

[0032] A water tank 4 is installed below the workbench 2, and a sealed pressurized water tank 5 is installed above the workbench 2. Water in the water tank 4 can be pumped to the sealed pressurized water tank 5 by a water pump 6. In this embodiment, the water pump 6 is a pneumatic water pump. The working principle of the pneumatic water pump is existing technology and will not be described in detail here. An air pump 7 is used to supply pressurized air to the sealed pressurized water tank 5. A first valve 81 is located in the air path between the air outlet of the air pump 7 and the air inlet of the sealed pressurized water tank 5. A second valve 82 is located in the water path between the water outlet of the water tank 4 and the water inlet of the sealed pressurized water tank 5. A third valve 83 is located in the air path between the air outlet of the sealed pressurized water tank 5 and the air inlet of the product under test 100. A fourth valve 84 is located in the water path between the water outlet of the sealed pressurized water tank 5 and the water inlet of the product under test 100. A fifth valve 85 is located in the water path between the drain outlet of the product under test 100 and the water tank 4. The water inlet of the product under test 100 is located above the drain outlet. In this embodiment, all of the above valves are solenoid valves, and the working states of water pump 6, air pump 7, first valve 81, second valve 82, third valve 83, fourth valve 84 and fifth valve 85 are all controlled by electrical control system 10.

[0033] In this embodiment, a water level sensor (not shown in the figure) is installed inside the sealed pressurized water tank 5. The water level sensor's sensing height is no higher than the height of the third valve 83 and higher than the height of the fourth valve 84. When the water level sensor is triggered, the water pump 6 stops working. In this embodiment, a pressure sensor 9 is installed in the water line between the drain outlet of the product under test 100 and the fifth valve 85. During pressure holding, the pressure sensor 9 can detect whether the internal pressure of the product under test 100 has decreased. In addition, the pressure sensor 9 can also be installed in the air line between the third valve 83 and the air inlet of the product under test 100, or in the water line between the fourth valve 84 and the water inlet of the product under test 100.

[0034] The working process of this water pressure testing device is as follows:

[0035] When water is introduced, pressing the start button causes the drive mechanism 11 to move the third cylinder 33 to the right. After the first cylinder 31 and the second cylinder 32 are aligned with the product under test 100, the first plug 311, the second plug 321, and the third plug 331 seal the product under test 100 under the push of their respective cylinders, and the water introduction program is initiated. The second valve 82 and the fourth valve 84 open, and the water pump 6 pumps water from the water tank 4 into the sealed pressurized water tank 5. The first valve 81 remains closed, and the third valve 83 is closed. The water in the sealed pressurized water tank 5 fills the product under test 100. Then, the fifth valve 85 closes. The fifth valve 85 closes with a delay during the water introduction stage to maximize the expulsion of air from the pipes and the product in the first few seconds after the water pump enters the pipes, thereby reducing the amount of air remaining in the pipes and the product during pressure holding and preventing the test water from flowing back into the sealed pressurized water tank 5. The delay time for closing the fifth valve should be greater than (the volume of test water filling the product's internal cavity and pipeline / the unit pump flow rate of the water pump). The volume of test water filling the product's internal cavity and pipeline = water filling the product + water filling a 1-meter-long pipeline with an inner diameter of 10mm ≈ 0.6L. When the input air pressure is between 0.6-0.8 MPa and there is no load, use a water pump with a discharge rate of approximately 8L / min, and set the fifth valve to close after 5-6 seconds. If testing different products, the water pump model can be changed according to the size of the product's internal cavity, or the discharge rate can be increased or decreased by adjusting the input air pressure. The delay time for closing the fifth valve can also be reset. All of the above methods are to ensure that the test water fills the product's internal cavity and pipeline as much as possible before the pressurization action. After the product under test is 100% full, the water pump 6 continues to work, and the water level in the sealed pressurized water tank 5 rises. When the water level sensor is triggered, the water pump 6 stops working.

[0036] During pressurization, the first valve 81 is opened and the second valve 82 is closed. The air pump 7 operates, and the pressurized air output from the air pump 7 enters the sealed pressurized water tank 5. The air pressure acts on the water surface in the sealed pressurized water tank 5. The fourth valve 84 remains open, and the pressure is transmitted to the product under test 100 through the fourth valve 84. Pressurization is complete when the pressure sensor 9 detects that the pressure has reached the set value. In this way, there is almost no loss of test water during the pressurization process, the water circulation is reasonable, and frequent water replenishment is not required. Furthermore, after replacing the pressurization equipment with the air pump 7, the pressurization speed is faster, the equipment price is lower, and the service life is longer. During pressurization, the third valve 83 and the fifth valve 85 remain closed.

[0037] Air pump 7 pressurizes the water at a standard inlet pressure of 0.6-0.8 MPa, while the pressure required for testing products is generally 1-1.5 MPa. During actual operation, air pump 7 is precisely controlled by electrical control system 10. Electrical control system 10 strictly regulates the output pressure of air pump 7 based on the pressure-bearing capacity of the sealed pressurized water tank 5 and the required testing pressure. When pressure sensor 9 detects that the pressure has reached the set value, electrical control system 10 controls the air pump to stop outputting pressure, ensuring that air pump 7 does not continuously pressurize beyond the water tank's pressure-bearing capacity. Furthermore, air pump 7 itself has a pressure testing device that limits the maximum pressure. The maximum output pressure of air pump 7 can be set. Even if electrical control system 10 fails, when air pump 7 continuously operates to a certain output pressure, the output pressure will remain at the upper limit and will not increase further. This upper limit will be less than the maximum pressure-bearing capacity of the sealed pressurized water tank 5. Therefore, theoretically, the situation where air pump 7 continuously pressurizes beyond the water tank's pressure-bearing capacity, causing the container to rupture and endangering operational safety, will not occur. Of course, to enhance safety, the sealed pressurized water tank 5 can be equipped with a pressure relief valve, or pressure can be released by opening valve 3. Alternatively, a protective plate can be installed around the device to ensure operator safety in extreme situations. During pressure holding, the pressure is maintained according to the set holding time. At this time, all solenoid valves are closed, and pressure sensor 9 detects whether the internal pressure of the product under test has decreased. When the product enters the pressure holding stage, the holding time is set according to process requirements (assumed to be 60 seconds, water pressure 1 MPa). During this period, the pressure in the pipeline and inside the product must remain consistent and stable. If ① a leak occurs due to seal failure, pressure sensor 9 will detect a drop in value and issue an alarm, indicating a test failure. ② If the water pressure remains at 1 MPa within 60 seconds, and the fluctuation value does not trigger an alarm, the electrical control system (programmable logic controller) will collect data and determine a successful test.

[0038] In fact, the product's qualification or failure has already been determined when the pressure holding stage ends. The purpose of opening the fifth valve 85 during the pressure relief stage is to drain the product and the test water in the pipeline into the water tank, and then replace the product with a new one via pneumatic operation. The installation location of the pressure sensor 9 and the water pressure during the pressure relief stage are unrelated to the pressure holding stage and the pressure holding result.

[0039] In addition, in the design of this device, pressure sensor 9 is mainly used to monitor the internal pressure of the product under test 100 in real time during the pressure holding phase. During pressure holding, all solenoid valves are closed, and pressure sensor 9 can reliably detect whether the internal pressure of the product under test 100 has decreased, thereby determining whether the product's sealing performance is good. When entering the pressure relief phase, the fifth valve 85 opens, and the focus of the device shifts from pressure holding monitoring to pressure relief and drainage. At this time, the role of pressure sensor 9 is not to detect pressure changes during the pressure holding phase, but to provide auxiliary data reference for the entire testing process. Even if the water pressure may drop rapidly to zero in the initial stage of pressure relief, it will not affect the accuracy of the data collected by pressure sensor 9 during the previous pressure holding phase, nor will it lead to misjudgment of the pressure holding results. Therefore, it can be seen that the pressure detection function of this device during the pressure holding phase can be realized normally.

[0040] During depressurization, the fifth valve 85 opens, reducing the internal water pressure of the test product 100 to zero. Subsequently, the third valve 83 opens, and the pressurized air in the sealed pressurized water tank 5 acts on the drainage pipeline and the test product 100 through the third valve 83, accelerating the drainage speed. Therefore, it is unnecessary to directly open the fourth valve 84 to pressurize and discharge the water from the sealed pressurized water tank 5, reducing the amount of water that needs to be discharged and the amount of water needed for the next product, thus improving efficiency. Furthermore, it makes efficient use of the air pressure used for pressurization and the air pressure remaining during pressure holding and depressurization, avoiding the need to simultaneously remove the water pressure from the test product 100 and the air pressure from the sealed pressurized water tank 5. During depressurization, the second valve 82 and the fourth valve 84 remain closed.

[0041] In this application, the air pump 7 pressurizes the sealed pressurized water tank 5. During the final pressure holding stage, the test pressure set by the product is basically the same as the pressure in the sealed pressurized water tank 5. Therefore, the pressure provided by the sealed pressurized water tank 5 during pressure relief and drainage will not be insufficient. In addition, the drain pipe uses a conventional high-pressure hose with an inner diameter of not less than 10mm. After about 2 seconds of entering the pressure relief stage, the air pressure input of the water pump 6 does not act on the piston pump water, but directly outputs an airflow of not less than 0.6MPa for 5 seconds to blow air. Therefore, there is no situation where residual water is not completely drained due to insufficient air pressure or too small a pipe diameter. On the contrary, the drainage speed can be increased by 3 times and the water droplets on the cavity wall can be discharged through the blowing airflow, minimizing the test water carried away when changing products.

[0042] The parameters of this application need to be adjusted according to the process document requirements of different test objects. Taking one of the products called sound and light explosion-proof boxes as an example, the water inlet time is set to 6 seconds, the pressurization time is 10 seconds after the electrical control system receives the pressure sensor and the pressure reaches the set pressure value, the pressure holding time is 2 seconds, the drainage time is 2 seconds, and the air blowing time is 3 seconds.

[0043] In addition, the test product 100 in this embodiment adopts a top water inlet and bottom drainage structure, which can make full use of the water's own gravity to drain the water, and will not cause test water residue in the test product 100.

Claims

1. A water pressure testing device, comprising a frame (1) and a worktable (2) disposed on the frame (1), wherein a clamping mechanism (3) for clamping a product (100) to be tested is mounted on the worktable (2), characterized in that It also includes: Water tank (4); Sealed pressurized water tank (5); A water pump (6) is used to transport water from the water tank (4) to the sealed pressurized water tank (5); An air pump (7) is used to supply pressurized air to the sealed pressurized water tank (5); The first valve (81) is located on the air path between the air outlet of the air pump (7) and the air inlet of the sealed pressurized water tank (5); The second valve (82) is located on the water line between the outlet of the water tank (4) and the inlet of the sealed pressurized water tank (5); The third valve (83) is located on the air path between the air outlet of the sealed pressurized water tank (5) and the air inlet of the product to be tested (100); The fourth valve (84) is located on the water line between the outlet of the sealed pressurized water tank (5) and the inlet of the product to be tested (100); The fifth valve (85) is located on the water line between the drain outlet of the product to be tested (100) and the water tank (4).

2. The water pressure testing device according to claim 1, characterized in that: A water level sensor is installed in the sealed pressurized water tank (5). The water level sensor's sensing height is not higher than the height of the third valve (83) and is higher than the height of the fourth valve (84). When the water level sensor is triggered, the water pump (6) stops working.

3. The water pressure testing device according to claim 1, characterized in that: It also includes a pressure sensor (9), which is installed in the water line between the drain outlet of the product under test (100) and the fifth valve (85), or in the air line between the third valve (83) and the air inlet of the product under test (100), or in the water line between the fourth valve (84) and the water inlet of the product under test (100).

4. The water pressure testing device according to claim 1, characterized in that: The water inlet of the product under test (100) is located above the drain outlet.

5. The water pressure testing device according to claim 1, characterized in that: The water pump (6) is a pneumatic water pump.

6. The water pressure testing device according to claim 1, characterized in that: The clamping mechanism (3) includes a first driving member arranged vertically, a second driving member and a third driving member arranged horizontally. The first driving member is located above the second driving member. In the detection state, the product to be tested (100) is clamped between the first driving member, the second driving member and the third driving member.

7. The water pressure testing device according to claim 6, characterized in that: The first driving component is a first cylinder (31), with the driving output end of the first cylinder (31) pointing vertically downwards. The second driving component is a second cylinder (32), with the driving output end of the second cylinder (32) pointing vertically upwards. The third driving component is a third cylinder (33), with the driving output end of the third cylinder (33) being set horizontally. A first plug (311) is installed at the driving output end of the first cylinder (31), a second plug (321) is installed at the driving output end of the second cylinder (32), and a third plug (331) is installed at the driving output end of the third cylinder (33). The product to be tested (100) is clamped between the first plug (311), the second plug (321), and the third plug (331).

8. The water pressure testing device according to claim 7, characterized in that: A drive mechanism (11) for driving the third cylinder (33) to move horizontally is installed below the worktable (2).

9. The water pressure testing device according to claim 1, characterized in that: The first valve (81), the second valve (82), the third valve (83), the fourth valve (84), and the fifth valve (85) are all solenoid valves.

10. The water pressure testing device according to any one of claims 1 to 9, characterized in that: It also includes an electrical control system (10) for controlling the working status of the water pump (6), air pump (7), first valve (81), second valve (82), third valve (83), fourth valve (84) and fifth valve (85).

Images