Performance testing apparatus and method for aviation lubricants

Abstract

This invention relates to the field of aviation oil testing technology, and discloses a performance testing device and method for aviation lubricating oil. The method includes the following steps: S1: Loading a sample into a test tank; the test tank includes an oxidation tube and a capillary tube; the bottom end of the oxidation tube is open, the bottom end of the capillary tube is integrally connected to the top end of the oxidation tube, and the top end of the capillary tube is open; during sample loading, a metal sheet is inserted into the oxidation tube from the bottom end opening and the opening is sealed; then, a lubricating oil sample is injected into the oxidation tube from the top end opening of the capillary tube and the opening is sealed; S2: Using the test tank after sample loading, performance testing is performed according to a preset test standard. The solution provided by this invention has high sample loading efficiency, high safety, and good stability of the constructed oxidation and corrosion environment, which helps to improve testing efficiency and accuracy.

Description

Technical Field

[0001] This invention relates to the field of aviation oil testing technology, and specifically to a performance testing device and method for aviation lubricating oil. Background Technology

[0002] To ensure the safe and stable operation of aircraft engines, a lubrication system is needed to provide a stable flow of aviation lubricating oil to all lubrication points. While effectively lubricating the engine's components, the aviation lubricating oil also carries away a significant amount of heat absorbed by the lubricated parts from the combustion of fuel, thus maintaining the engine at a stable operating temperature. Therefore, during its circulation, the aviation lubricating oil undergoes a continuous cycle of heat absorption, heating, oxidation, and cooling. During this process, the oil is prone to evaporation, coking, and corrosion. This places extremely stringent requirements on aircraft engine lubricating oils. Determining whether an aviation lubricating oil meets the basic requirements of an aircraft engine requires testing and evaluating multiple performance characteristics according to specific standards.

[0003] Among these, the oxidation and corrosion stability test and the thermal oxidation stability test of aviation lubricating oil are important evaluation items. Both of these tests require the use of test tubes for sample preparation. The aviation lubricating oil sample to be tested and a metal strip are placed in the test tube to create an oxidation and corrosion environment. Current aviation testing standards require the use of test tubes with capillary tubes at the open end for sample preparation, as shown in the attached... Figure 1 As shown, the oil sample is introduced into the test tube through a capillary tube, while the metal sheet needs to be inserted into the test tube through the fracture after the test tube is cut, and then the fracture is fused together. Although this sample loading method can construct a standard oxidation and corrosion environment, the sample loading efficiency is low, there is a risk of test tube breakage during the cutting and fusion steps, and the safety is not high; moreover, there is still room for optimization of the constructed oxidation and corrosion environment. Summary of the Invention

[0004] The present invention aims to provide a performance testing device and method for aviation lubricating oils, which has high sample loading efficiency, high safety, and good stability of the constructed oxidation and corrosion environment, thereby helping to improve testing efficiency and accuracy.

[0005] To achieve the above objectives, the basic solution provided by this invention is as follows:

[0006] Option 1

[0007] Performance testing methods for aviation lubricants include the following steps:

[0008] S1: Loading the sample into the test chamber; the test chamber includes an oxidation tube and a capillary tube; the bottom end of the oxidation tube is open, the bottom end of the capillary tube is integrally connected to the top end of the oxidation tube, and the top end of the capillary tube is open; when loading the sample, a metal sheet is inserted into the oxidation tube from the bottom end opening and the opening is sealed; then a lubricating oil sample is injected into the oxidation tube from the top end opening of the capillary tube and the opening is sealed.

[0009] S2: Use the test tank after the sample is loaded to conduct performance tests according to the preset test standards.

[0010] Furthermore, the metal sheet is a pre-treated metal sheet; the pre-treatment operation includes: polishing the surface of the metal sheet, cleaning the surface of the metal sheet, and weighing the metal sheet.

[0011] Furthermore, during sample loading, a metal sheet is inserted into the opening at the bottom of the oxidation tube and the opening is sealed. Then, the test gas is injected into the test cell through the opening at the top of the capillary tube, and the opening at the top of the capillary tube is sealed.

[0012] Furthermore, when injecting the lubricating oil sample into the oxidation tube, the capillary is first cut to obtain a new capillary tip opening, and the lubricating oil sample is injected into the oxidation tube through the new capillary tip opening; then, the test cell is evacuated through the new capillary tip opening to create a vacuum environment in the test cell, and the capillary is melted off from the bottom of the new capillary tip opening and the opening is sealed.

[0013] Furthermore, with the test tank placed vertically, the level of the injected lubricating oil sample was lower than the top of the steel sheet.

[0014] Furthermore, when the capillary is melted off and the opening is sealed from the lower part of the new capillary tip opening, the test cell is kept evacuated at the new capillary tip opening.

[0015] Furthermore, the preset test standard includes inserting the test pool into a constant temperature bath, removing the test pool after a preset test cycle and cooling it to room temperature; and then taking samples of the lubricating oil and metal sheets in the test pool for analysis.

[0016] Furthermore, the test gas is nitrogen.

[0017] Option 2

[0018] A performance testing device for aviation lubricating oils, applied to the performance testing method for aviation lubricating oils as described in Scheme 1; comprising a constant temperature bath and a test tank; the test tank includes an oxidation tube and a capillary tube; the bottom end of the capillary tube is integrally connected to the top end of the oxidation tube; the test tank is used to contain lubricating oil samples and metal sheets and constitute a performance testing environment; the constant temperature bath is used to contain and keep the test tank at a constant temperature.

[0019] The working principle and advantages of this invention are as follows:

[0020] This invention breaks through the limitations of existing aviation testing standards and establishes a completely new sample loading method. In the sample loading methods provided by existing standards, based on the conventional top-down approach, the method involves cutting the test tube in the middle, placing a metal sheet, and then fusing the test tube, with the metal sheet placement opening located in the upper part of the test tube. While this operation seems more in line with conventional sample loading logic, in practice, fusing the test tube is difficult due to the larger diameter of the middle section and the difficulty of sealing the surrounding area. Air bubbles are easily generated at the fusion point, failing to achieve the theoretical sealing effect of the standard method. During the subsequent heating stage, the air bubbles at the fusion point are affected by the high temperature environment, increasing the pressure within the bubbles and making the fusion point prone to bursting, posing a serious safety risk and directly disrupting the test process. This solution addresses these issues by breaking through the limitations of the conventional sample loading approach and adjusting the loading method. When loading the metal sheet, there is no need to cut and then fuse the test tube (oxidation tube). Instead, an oxidation tube with a bottom opening is used, and the metal sheet is directly placed into the tube through the opening and the bottom opening is sealed, completing the placement of the metal sheet. It offers higher sample loading efficiency and greater operational safety.

[0021] Furthermore, after the metal sheet is loaded into the oxidation tube, this method uses nitrogen to replace and remove air and moisture from the tube, and seals the top opening of the capillary tube. Under these conditions, the metal sheet inside the oxidation tube is kept in a stable environment, and the surface quality of the metal sheet remains stable. Based on this, lubricating oil samples are added. After addition, a vacuum environment is maintained and the capillary tube is sealed. Under these conditions, the internal environment of the test cell is not affected by external gases, creating a pure interaction environment between the lubricating oil and the metal sheet. The constructed oxidation and corrosion environment has good stability, which helps improve test accuracy. In addition, since the influence of external environmental factors such as air and moisture has been eliminated from the test cell during sample loading, this method does not require additional heating and shaking steps to remove air and moisture from the test cell, as is required in conventional test methods. The overall test process of this method is simpler and more efficient. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the standard sample loading method commonly used.

[0023] Figure 2 This is a schematic diagram of the sample loading method in S1 of an embodiment of the performance testing device and method for aviation lubricating oil of the present invention;

[0024] Figure 3 This is a first schematic diagram of the sample loading method in S1 of an embodiment of the performance testing device and method for aviation lubricating oil of the present invention.

[0025] Figure 4This is a second schematic diagram of the sample loading method in embodiment S1 of the performance testing device and method for aviation lubricating oil of the present invention. Detailed Implementation

[0026] The following detailed explanation illustrates the specific implementation methods:

[0027] The markings in the accompanying drawings include: oxide tube 1, capillary tube 2, and metal sheet 3.

[0028] The basic implementation examples are as follows: Figure 2 The following is a performance testing method for aviation lubricants, including the following steps:

[0029] S1: Load the sample into the test chamber, as shown in the attached diagram. Figure 2 As shown.

[0030] The test cell includes an oxidation tube 1 and a capillary tube 2; the bottom end of the oxidation tube 1 is open, the bottom end of the capillary tube 2 is integrally connected to the top end of the oxidation tube 1, and the top end of the capillary tube 2 is open. In this embodiment, the test cell is made of borosilicate glass, which has a low expansion rate, good resistance to chemical corrosion and thermal shock, and is suitable for aviation fuel testing environments with long testing cycles and high temperatures.

[0031] During sample loading, a metal sheet 3 is inserted into the oxidation tube 1 through the bottom opening and the opening is sealed. Here, the diameter of the bottom opening is larger than the diameter of the metal sheet 3. A conventional sealing machine is used to seal the bottom opening, with the sealing temperature set at 1200–1500℃ and the sealing time controlled at 5–10 minutes. Under these conditions, the bottom opening is fully sealed with high quality, and air bubbles are less likely to form. Then, a lubricating oil sample is injected into the oxidation tube 1 through the top opening of the capillary tube 2 and the opening is sealed.

[0032] Specifically, as shown in the attached document Figure 3 As shown, during sample loading, a metal sheet 3 is inserted into the opening at the bottom of the oxidation tube 1 and the opening is sealed. Then, the test gas is injected into the test cell through the opening at the top of the capillary tube 2, and the opening at the top of the capillary tube 2 is sealed. The test gas is nitrogen. By injecting nitrogen, the air in the test cell can be evenly expelled, preventing air and moisture from affecting the metal sheet 3. The metal sheet 3 is a pre-treated metal sheet; in this embodiment, a steel sheet is used. The pre-treatment operations include: polishing the surface of the metal sheet 3, including using sandpaper to polish the spots and burrs on the surface of the metal sheet 3, making the surface of the metal sheet 3 a smooth mirror finish; cleaning the surface of the metal sheet 3, including wiping the metal sheet 3 with degreased cotton in petroleum ether and acetone respectively; and weighing the metal sheet 3, with a weighing accuracy requirement of 0.1 mg.

[0033] Furthermore, as shown in the appendix Figure 4As shown, a lubricating oil sample is injected into the oxidation tube 1. During this process, the capillary tube 2 is first cut to obtain a new opening at the top of the capillary tube 2. The lubricating oil sample is then injected into the oxidation tube 1 through the new opening at the top of the capillary tube 2 using a syringe needle or similar tool. In this embodiment, approximately 15 ml of lubricating oil sample is injected. A vacuum is then created in the test chamber through the new opening at the top of the capillary tube 2, forming a vacuum environment. Finally, the capillary tube 2 is melted off from the bottom of the new opening at the top of the capillary tube 2, and the opening is sealed.

[0034] During sample loading, after inserting the metal sheet 3 into the opening at the bottom of the oxidation tube 1 and sealing the opening, the test gas is then injected into the test cell through the opening at the top of the capillary tube 2, and the opening at the top of the capillary tube 2 is then sealed. Furthermore, when the capillary tube 2 is melted off from the bottom of the new capillary tube 2 opening and the opening is sealed, the test cell is kept under vacuum at the new capillary tube 2 opening to prevent air from entering the oxidation tube 1.

[0035] Furthermore, with the test tank placed vertically, the level of the injected lubricating oil sample was lower than the top of the steel sheet.

[0036] S2: Use the test tank after the sample is loaded to conduct performance tests according to the preset test standards.

[0037] The preset test standard includes inserting the test pool into a constant temperature bath, removing the test pool after a preset test cycle and cooling it to room temperature; and then taking samples of the lubricating oil and metal sheet 3 in the test pool for analysis.

[0038] Specifically, when conducting oxidation and corrosion stability tests on aviation lubricating oils, the preset test period is set to 72 hours, and the temperature of the constant temperature bath is 100-300℃. In this embodiment, it can be specifically set to 175℃, 204℃, or 218℃. When conducting thermal oxidation stability tests on aviation lubricating oils, the preset test period is set to 96 hours, and the temperature of the constant temperature bath is 274±1℃.

[0039] This embodiment also provides a performance testing device for aviation lubricating oil, applied to the performance testing method for aviation lubricating oil as described above; it includes a constant temperature bath and a test pool; the test pool includes an oxidation tube 1 and a capillary tube 2; the bottom end of the capillary tube 2 is integrally connected to the top end of the oxidation tube 1; the test pool is used to contain the lubricating oil sample and the metal sheet 3 and constitute a performance testing environment; the constant temperature bath is used to contain and keep the test pool at a constant temperature.

[0040] This embodiment provides a performance testing device and method for aviation lubricating oil, which sets a brand-new sample loading method. During the sample loading process, for the oxidation tube 1, the metal sheet 3 can be inserted from the bottom opening of the oxidation tube 1. It is not necessary to cut and fuse the oxidation tube 1 from the middle to place the metal sheet 3. This solution only needs to seal the bottom opening to complete the placement of the metal sheet 3. The operation process is safer and the sample loading efficiency is higher.

[0041] Furthermore, after the metal sheet 3 is loaded into the oxidation tube 1, nitrogen is used to replace and remove air and moisture from the tube, and the top opening of the capillary tube 2 is sealed. The metal sheet 3 inside the oxidation tube 1 is in a stable environment, ensuring stable surface quality. Based on this, lubricating oil samples are added. After addition, a vacuum environment is maintained, and the capillary tube 2 is sealed. This setup prevents the internal environment of the test chamber from being affected by external gases, creating a pure interaction environment between the lubricating oil and the metal sheet 3, which helps improve test accuracy. In addition, since the influence of external environmental factors such as air and moisture has been eliminated from the test chamber during sample loading, this scheme does not require additional heating and shaking steps to remove air and moisture from the test chamber, unlike conventional test schemes. The overall test process of this scheme is simpler and more efficient.

[0042] The above descriptions are merely embodiments of the present invention. Commonly known structures and characteristics of the solutions are not described in detail here. Those skilled in the art are aware of all common technical knowledge in the field prior to the application date or priority date, are aware of all existing technologies in that field, and have the ability to apply conventional experimental methods prior to that date. Those skilled in the art can, based on the guidance provided in this application, improve and implement this solution in conjunction with their own capabilities. Some typical known structures or methods should not be obstacles for those skilled in the art to implement this application. It should be noted that those skilled in the art can make several modifications and improvements without departing from the structure of the present invention. These should also be considered within the scope of protection of the present invention, and will not affect the effectiveness of the implementation of the present invention or the practicality of the patent.

Claims

1. A performance testing method for aviation lubricating oils, characterized in that, Includes the following steps: S1: Loading the sample into the test chamber; the test chamber includes an oxidation tube and a capillary tube; the bottom end of the oxidation tube is open, the bottom end of the capillary tube is integrally connected to the top end of the oxidation tube, and the top end of the capillary tube is open; during sample loading, a metal sheet is loaded into the oxidation tube from the bottom end opening and the opening is sealed; then, a lubricating oil sample is injected into the oxidation tube from the top end opening and the opening is sealed; the diameter of the bottom end opening is larger than the diameter of the metal sheet, the sealing temperature is set to 1200~1500℃, and the sealing time is controlled to 5~10min; During sample loading, a metal sheet is inserted into the opening at the bottom of the oxidation tube and the opening is sealed. Then, the test gas is injected into the test cell through the opening at the top of the capillary tube and the opening at the top of the capillary tube is sealed. The test gas is nitrogen. When injecting the lubricating oil sample into the oxidation tube, the capillary is first cut to obtain a new capillary top opening, and the lubricating oil sample is injected into the oxidation tube through the new capillary top opening; then the test cell is evacuated through the new capillary top opening to create a vacuum environment in the test cell, and the capillary is melted off from the bottom of the new capillary top opening and the opening is sealed. S2: Use the test tank after the sample is loaded to conduct performance tests according to the preset test standards.

2. The performance testing method for aviation lubricating oil according to claim 1, characterized in that, The metal sheet is a pre-treated metal sheet; The pretreatment operations include: grinding the surface of the metal sheet, cleaning the surface of the metal sheet, and weighing the metal sheet.

3. The performance testing method for aviation lubricating oil according to claim 1, characterized in that, With the test tank placed vertically, the level of the injected lubricating oil sample was lower than the top of the steel sheet.

4. The performance testing method for aviation lubricating oil according to claim 1, characterized in that, When the capillary tube is melted off and the opening is sealed from the bottom of the new capillary tube tip opening, the test cell is kept under vacuum at the new capillary tube tip opening.

5. The performance testing method for aviation lubricating oil according to claim 1, characterized in that, The preset test standard includes inserting the test pool into a constant temperature bath, removing the test pool after a preset test cycle and cooling it to room temperature; and then taking samples of the lubricating oil and metal sheets in the test pool for analysis.

6. A performance testing device for aviation lubricating oil, characterized in that, The method for testing the performance of aviation lubricating oil as described in any one of claims 1-5 includes a constant temperature bath and a test tank; the test tank includes an oxidation tube and a capillary tube; the bottom end of the capillary tube is integrally connected to the top end of the oxidation tube; the test tank is used to contain the lubricating oil sample and the metal sheet and to form a performance testing environment; the constant temperature bath is used to contain and keep the test tank at a constant temperature.

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