Immersion leakage testing device for air-cooled oil pan and use method of immersion leakage testing device

Abstract

The invention provides a soaking leakage testing device for an air-cooled oil pan and a using method thereof, belongs to the field of machining, and aims to solve the problems that in an existing oil pan leakage testing method, a full-automatic tool is high in cost, traditional soaking leakage testing is low in efficiency, and potential safety hazards exist. The device comprises a water tank and a sealing tool assembly, the water tank is separated by a water cavity and a leakage testing water cavity through a partition plate, the two cavities are communicated only through a water pipe extending to the bottom of the water cavity, and the volume of the water cavity is larger than that of the leakage testing water cavity; the sealing tool assembly comprises a sealing plate, a pressing device and the like and is used for sealing an inner cavity of the oil pan. According to the method, the water level is controlled through air pressure, compressed air is filled into the water cavity to enable water to flow into the leakage testing water cavity through the water pipe to submerge the oil pan, and surface bubbles are observed to judge the sealing performance; water flows back after exhausting, and a tool does not need to be hoisted and transferred. The cost performance and the safety are both considered, the operation efficiency is improved, the leakage point can be accurately positioned, and the method is suitable for a small-batch production scene.

Description

Technical Field

[0001] This invention belongs to the field of mechanical processing technology, and more specifically, it relates to a water immersion leak testing device for air-cooled oil pans and its usage method. Background Technology

[0002] As a critical component of the engine, the oil pan's sealing performance directly affects the engine's normal operation. Therefore, sealing testing is an indispensable step in the manufacturing process. Leak testing can promptly detect oil pan components with substandard sealing, preventing leaks in the entire engine after installation and ensuring the engine's operational reliability.

[0003] Currently, the industry mainly uses two methods for sealing tests of oil pans:

[0004] One method is the fully automated tooling-assisted clamping and sealing leak testing method. This method involves placing a cleaned oil pan on the sealing plate according to the pin holes. A start button controls a clamping cylinder (either pneumatic or hydraulic) to automatically clamp the oil pan, while simultaneously rapidly filling the oil pan cavity with compressed gas. The sealing performance is then determined by observing the pressure gauge readings. The advantage of this method is its high degree of automation, reducing labor intensity. However, its disadvantages include high specialization requirements and the need for expensive dedicated equipment. For small-batch production or small workshops, the cost-effectiveness is extremely low, making widespread application difficult.

[0005] Another method is the immersion leak test. This method requires assembling the oil pan and the sealing fixture together and then placing them in water to observe whether bubbles are generated to determine the seal. Its advantage is that the location of leaks in the components can be directly observed, facilitating marking and subsequent repairs. However, its disadvantages are also significant. Firstly, this method requires repeated hoisting and moving of the oil pan and sealing fixture assembly, which is cumbersome and leads to low leak testing efficiency. Secondly, since the sealing fixture is usually quite heavy, accidents can easily occur during hoisting and moving, posing certain safety hazards.

[0006] In response to the problems of high cost, low efficiency and insufficient safety in existing technologies, there is an urgent need for an oil pan immersion leak testing solution that balances cost-effectiveness, safety and operational efficiency. Summary of the Invention

[0007] To address the aforementioned technical problems, this invention provides a water immersion leak testing device for air-cooled oil pans and its usage method, thereby resolving the problems described above.

[0008] A water immersion leak testing device for an air-cooled oil pan includes a water tank and a sealing fixture assembly;

[0009] The water tank consists of two parts: a water chamber and a leak test water chamber, which are separated by a welded partition.

[0010] A water pipe is welded to the partition, the lower end of the water pipe extends to the bottom of the water cavity, and the volume of the water cavity is larger than the volume of the test leak water cavity.

[0011] The partition is also connected to an air inlet and an exhaust outlet.

[0012] The sealing tooling assembly includes a flat plate, a sealing gasket, a pressure plate, and several sets of clamping devices. The sealing gasket is placed on the flat plate, the pressure plate is used to clamp the oil pan mating surface, and the clamping devices are distributed on the sealing plate to ensure the sealing of the oil pan cavity.

[0013] The oil drain hole of the oil pan serves as the second air inlet, used to fill the inner cavity of the oil pan with compressed gas; a drain nut is provided at the bottom of the water cavity.

[0014] Preferably, the plurality of clamping devices are used to press the oil pan onto the sealing gasket to ensure a seal between the oil pan and the sealing gasket.

[0015] Preferably, the water pipe is the only connecting pipe between the water chamber and the leak test water chamber, and the water flow between the two chambers is only achieved through this water pipe.

[0016] Preferably, the exhaust port is equipped with a valve to control the discharge of gas from the water tank; the air inlet is equipped with a valve to control the injection of compressed gas into the water chamber.

[0017] Preferably, the upper surface of the plate is the upper boundary of the leak test chamber, and the sealing gasket is set on the plate at the position corresponding to the oil pan.

[0018] Another technical problem to be solved by the present invention is to provide a water immersion leak testing method for an immersion leak testing device for an air-cooled oil pan, comprising the following steps:

[0019] Step 1: Open the exhaust valve and close the inlet valve. Fill the water tank with water up to no higher than the top surface of the plate. Under atmospheric pressure, the lower water chamber of the tank will be filled with water. Step 2: Place the oil pan on the sealing gasket on the plate. Press the pressure plate firmly against the oil pan's mating surface. Then, fill the inner cavity of the oil pan with compressed gas through the oil drain hole (inlet valve 2). Step 3: Close the exhaust valve and open the inlet valve to fill the water chamber with compressed gas, allowing the water in the water chamber to flow into the leak test chamber through the water pipe. Continue until the water level completely covers the bottom of the oil pan, then close the air inlet valve 1; Step 4: Observe whether bubbles are generated on the surface of the oil pan to determine its sealing performance; Step 5: After the test, close the air inlet valve 2 to stop the injection of compressed gas, open the exhaust valve to discharge the compressed gas in the water chamber, allowing the water in the leak test water chamber to flow back into the water chamber, loosen the pressure plate and remove the oil pan; Step 6: Repeat steps 1-5 to test the next oil pan; If a batch of tests is completed, open the drain nut to drain the water in the water chamber.

[0020] Preferably, in step 1, when filling the water tank, the vent valve must be kept open until the water chamber is full of water.

[0021] Preferably, in step 2, compressed gas is injected into the inner cavity of the oil pan through the oil drain hole as the second air inlet to ensure that the inner cavity of the oil pan is filled with gas.

[0022] Preferably, in step 3, during the process of filling the water chamber with compressed gas, the water level in the leak test water chamber gradually rises. When the water level completely submerges the bottom surface of the oil pan, the air inlet valve is immediately closed.

[0023] Preferably, in step 6, after a batch of tests is completed, the drain nut is opened to completely drain the water in the water chamber, and before the next use, the water in the tank is replenished to a level not higher than the upper surface of the plate.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] Balancing cost-effectiveness and economy: Compared with the fully automated tooling for sealing leak testing in the same industry, the leak testing tooling of this invention is composed of simple parts such as a water tank and a sealing tooling assembly. The structure is simplified, no high investment in professional equipment is required, and the economic cost is low. It is especially suitable for small-batch production or small workshops, and has a higher cost-effectiveness.

[0026] Improved operational efficiency and convenience: Compared to the traditional method of immersing the oil pan and sealing fixture together in water, this invention uses a water chamber and a leak test chamber structure design to control the water level rise and fall with air pressure. This eliminates the need to repeatedly hoist and move heavy sealing fixtures, reduces operational steps, shortens the auxiliary time for each leak test, and effectively improves operational efficiency. Moreover, the operation process is simple, and water level adjustment and gas filling and venting can be achieved through valve control, making it easy to get started quickly.

[0027] Enhanced operational safety: Traditional immersion leak testing methods pose safety hazards during the hoisting and transfer process due to the weight of the sealing fixtures. However, this invention, through a fixed water tank structure and a pneumatically driven water level design, avoids frequent hoisting and movement of the sealing fixtures, reduces safety risks during operation, and ensures operational safety.

[0028] Precisely locate the leak and facilitate repair: This invention uses a leak test method in which the entire oil pan is submerged in water. This allows direct observation of the bubbles generated on the surface of the oil pan, thus clearly identifying the leak location. Compared with the traditional water immersion leak test method, it retains the advantage of "precisely marking the leak point", which facilitates subsequent targeted repair.

[0029] The structure is reasonably designed and highly practical: the water tank and leak test water chamber volume design, the connection method of water pipe and baffle, etc., ensure that the water can stably submerge the oil pan to meet the leak test requirements; the clamping device and sealing gasket design of the sealing tooling assembly ensure the effective sealing of the oil pan cavity. The overall structure has high adaptability, can be reused, meets the needs of continuous leak test operations, and is highly practical. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0031] In the diagram, the correspondence between the component names and the attached drawing numbers is as follows: 1. Water tank; 2. Exhaust port; 3. Air inlet 2; 4. Oil pan; 5. Pressure plate; 6. Leak test water chamber; 7. Flat plate; 8. Sealing gasket; 9. Air inlet 1; 10. Water pipe; 11. Water chamber; 12. Drain nut. Detailed Implementation

[0032] The embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and should not be construed as limiting the scope of the invention.

[0033] Please see Figure 1 This invention provides a water immersion leak testing device for air-cooled oil pans and its usage method. The structure of the leak testing device is as follows:

[0034] It mainly consists of two parts: water tank 1 and sealing fixture assembly. The specific structure and connection relationship of each part are as follows:

[0035] Water tank 1 is made of welded steel plate and is divided into two chambers, namely water chamber 11 and leak test chamber 6. The two chambers are separated by a steel plate (partition) with a thickness of 8-10mm. The partition is connected to the inner wall of water tank 1 by continuous welding process. After welding, a water pressure test is required (test pressure 0.2MPa, pressure held for 5 minutes without leakage) to ensure that there is no water leakage between the two chambers.

[0036] The two chambers are connected only by a water pipe 10 welded to the partition. The lower end of the water pipe 10 extends to the bottom of the water chamber 11, which is the only channel for water to flow between the two chambers.

[0037] The partition is also connected to an air inlet 9 and an exhaust port 2. Both the air inlet 9 and the exhaust port 2 are connected to the partition by full welding. The weld is polished smooth to ensure a seal.

[0038] The volume of water chamber 11 is larger than that of test leak water chamber 6. The specific ratio is designed according to the height of oil pan 4. Usually, the volume of water chamber 11 is 1.5-2 times that of test leak water chamber 6 (for example, when the volume of test leak water chamber 6 is 50L, the volume of water chamber 11 is designed to be 75-100L) to ensure that the water can completely submerge oil pan 4 during the test and leave a safety height of 50-100mm.

[0039] The bottom of the water chamber 11 is equipped with a drain nut 12, which is an M20 size hexagonal nut with a washer. The nut is connected to the drain hole at the bottom of the water chamber 11 by a thread. The thread is wrapped with PTFE tape to enhance the seal. It is used to drain the water in the water chamber 11 after the test.

[0040] Sealing tooling assembly:

[0041] The sealing fixture assembly includes a flat plate 7, a sealing gasket 8, a pressure plate 5, several sets of clamping devices, and locating pins. Its specific structure is as follows:

[0042] The upper surface of the plate 7 is the upper boundary of the leak test chamber 6. It is equipped with a positioning pin that matches the shape of the oil pan 4, which is used for precise positioning when the oil pan 4 is placed to ensure that the mating surface of the oil pan 4 is completely aligned with the sealing gasket 8.

[0043] The sealing gasket 8 is made of oil-resistant rubber (such as nitrile rubber), and its shape matches the contour of the mating surface of the oil pan 4. It has a thickness of 3-5mm and is fixed to the corresponding position of the plate 7 by bolts. The elasticity of the rubber compensates for the small processing errors of the mating surface of the oil pan 4 to ensure the sealing effect.

[0044] The pressure plate 5 is used to press the mating surface of the oil pan 4, and it is connected to several sets of pressing devices. The pressing devices are distributed on the edge of the sealing plate and adopt a manual spiral pressing structure: each set includes a pressing bolt, a bracket and a pressure plate connector. The bracket is fixed to the sealing plate, and the pressing bolt passes through the bracket and is threadedly connected to the pressure plate connector. By rotating the pressing bolt, the pressure plate 5 can be driven to apply vertical pressure to the mating surface of the oil pan 4 to ensure the sealing of the inner cavity of the oil pan 4.

[0045] The drain hole of the oil pan 4 serves as the air inlet 3, used to fill the inner cavity of the oil pan 4 with compressed gas.

[0046] Leak testing procedure:

[0047] Preparation before the experiment:

[0048] Open the exhaust port 2 valve and close the air inlet 9 valve. Fill the water tank 1 with water until the water level is no higher than the upper surface of the plate 7. Under atmospheric pressure, the water chamber 11 at the bottom of the water tank 1 will be automatically filled with water.

[0049] Installation and pretreatment of oil pan 4:

[0050] Position the oil pan 4 to be tested using the positioning pin on the plate 7 and place it on the sealing gasket 8; rotate the clamping bolt of the clamping device to drive the pressure plate 5 to tightly press the mating surface of the oil pan 4, ensuring a good seal between the oil pan 4 and the sealing gasket 8; then, fill the inner cavity of the oil pan 4 with compressed gas (gas pressure 0.2-0.3MPa) through the air inlet 2 3 (oil pan drain hole) until the inner cavity is completely filled with gas.

[0051] Water immersion leak test process:

[0052] Close the exhaust port 2 valve and open the air inlet 9 valve to fill the water chamber 11 with compressed gas (gas pressure 0.3-0.5MPa). Under the action of air pressure, the water in the water chamber 11 will flow upward through the water pipe 10 to the leak test water chamber 6. The side wall of the leak test water chamber 6 is equipped with a tempered glass transparent observation window, which can be used to directly observe the water level. When the water level completely covers the bottom surface of the oil pan 4 (50-100mm above the bottom surface), close the air inlet 9 valve.

[0053] At this time, the part above the bottom of the water pipe 10 in the water chamber 11 is filled with gas, and the oil pan 4 in the leak test water chamber 6 is completely submerged in water. The inner cavity of the oil pan 4 is kept under high pressure due to the pre-filled compressed gas. Observe whether there are bubbles on the surface of the oil pan 4. If there are bubbles, it indicates that there is a leak. The location of the bubbles is the leak point.

[0054] Post-test processing:

[0055] After the leak test is completed, close the air inlet 2 3 to stop the injection of compressed gas, open the exhaust valve 2, and the compressed gas in the water chamber 11 will be discharged through the exhaust valve 2; under atmospheric pressure, the water in the leak test water chamber 6 will flow back to the water chamber 11 through the water pipe 10, and the water level will gradually drop below the upper surface of the plate 7.

[0056] Rotate the tightening bolt in the opposite direction to loosen the pressure plate 5, remove the oil pan 4 and clean it. Repeat the steps to test the next oil pan 4 for leaks.

[0057] Once the leak test of a batch of oil pan 4 is completed, open the drain nut 12 at the bottom of the water chamber 11 to completely drain the water in the water chamber 11. Before the next use, fill the water tank 1 with water until it is no higher than the upper surface of the plate 7.

[0058] Through the above-described structural design and operating procedure, this invention can clearly observe the leakage location of the oil pan 4, reduce costs by simplifying the tooling structure, and avoid the safety hazards of traditional hoisting and transfer. It is suitable for sealing detection in small-batch production scenarios.

[0059] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A water immersion leak testing device for an air-cooled oil pan, characterized in that: Includes a water tank (1) and a sealing tooling assembly; The water tank (1) consists of two parts: a water chamber (11) and a leak test water chamber (6), which are separated by a welded partition. A water pipe (10) is welded to the partition plate. The lower end of the water pipe (10) extends to the bottom of the water cavity (11), and the volume of the water cavity (11) is greater than the volume of the test leak water cavity (6). The partition is also connected to an air inlet (9) and an exhaust outlet (2); The sealing fixture assembly includes a flat plate (7), a sealing gasket (8), a pressure plate (5), and several sets of clamping devices. The sealing gasket (8) is placed on the flat plate (7), the pressure plate (5) is used to clamp the mating surface of the oil pan (4), and the clamping devices are distributed on the sealing plate to ensure the sealing of the inner cavity of the oil pan (4). The oil drain hole of the oil pan (4) serves as the second air inlet (3) for filling the inner cavity of the oil pan (4) with compressed gas; the bottom of the water cavity (11) is provided with a drain nut (12).

2. The water immersion leak testing device for an air-cooled oil pan as described in claim 1, characterized in that, The plurality of clamping devices are used to press the oil pan (4) onto the sealing gasket (8) to ensure a seal between the oil pan (4) and the sealing gasket (8).

3. The water immersion leak testing device for an air-cooled oil pan as described in claim 2, characterized in that, The water pipe (10) is the only connecting pipe between the water chamber (11) and the test leak water chamber (6), and the water flow between the two chambers is only achieved through the water pipe (10).

4. The water immersion leak testing device for an air-cooled oil pan as described in claim 3, characterized in that, The exhaust port (2) is equipped with a valve to control the discharge of gas in the water tank (1); the air inlet (9) is equipped with a valve to control the filling of compressed gas into the water chamber (11).

5. The water immersion leak testing device for an air-cooled oil pan as described in claim 4, characterized in that, The upper surface of the plate (7) is the upper boundary of the leak test chamber (6), and the sealing gasket (8) is set on the plate (7) at the position corresponding to the oil pan (4).

6. A water immersion leak testing method for a water immersion leak testing device for an air-cooled oil pan, characterized in that, Includes the following steps: Step 1: Open the exhaust port (2) valve, close the air inlet one (9) valve, and fill the water tank (1) with water up to the upper surface of the plate (7). Under atmospheric pressure, the lower water chamber (11) of the water tank (1) will be filled with water. Step 2: Place the oil pan (4) on the sealing gasket (8) on the plate (7), press the pressure plate (5) against the mating surface of the oil pan (4), and then fill the inner cavity of the oil pan (4) with compressed gas through the oil drain hole (air inlet two (3)). Step 3: Close the exhaust port (2) valve, open the air inlet one (9) valve, and fill the water chamber (11) with compressed gas, so that the water in the water chamber (11) flows through the water pipe (10). ) Flow into the test leak chamber (6) until the water level completely covers the bottom surface of the oil pan (4), and close the air inlet valve (9); Step 4: Observe whether there are bubbles on the surface of the oil pan (4) to judge its sealing performance; Step 5: After the test, close the air inlet valve (3) to stop the filling of compressed gas, open the exhaust valve (2) to discharge the compressed gas in the water chamber (11), so that the water in the test leak chamber (6) flows back to the water chamber (11), loosen the pressure plate (5) and remove the oil pan (4); Step 6: Repeat steps 1-5 to test the next oil pan (4); If a batch of tests is completed, open the drain nut (12) to drain the water in the water chamber (11).

7. The method according to claim 6, characterized in that, In step 1, when filling the water tank (1) with water, the vent (2) valve must be kept open until the water chamber (11) is full of water.

8. The method according to claim 6, characterized in that, In step 2, compressed gas is injected into the inner cavity of the oil pan (4) through the oil drain hole (3) as the air inlet (3) to ensure that the inner cavity of the oil pan (4) is filled with gas.

9. The method according to claim 6, characterized in that, In step 3, during the process of filling the water chamber (11) with compressed gas, the water level in the test leak water chamber (6) gradually rises. When the water level completely submerges the bottom surface of the oil pan (4), the air inlet valve (9) is immediately closed.

10. The method according to claim 6, characterized in that, In step 6, after a batch of tests is completed, open the drain nut (12) to completely drain the water in the water chamber (11). Before the next use, fill the water tank (1) with water until it is no higher than the upper surface of the plate (7).

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