Aviation hydraulic oil composition as well as preparation method and application thereof

Abstract

The invention belongs to the field of special oil for aircraft hydraulic systems, and particularly relates to an aviation hydraulic oil composition as well as a preparation method and application thereof. The aviation hydraulic oil composition comprises the following raw materials in percentage by mass: 15%-20% of a viscosity index improver, 0.01%-1% of an antioxidant, 0.01%-1% of an anti-wear agent, 0.1%-2.0% of an anti-rust agent, 0.01%-0.1% of an anti-foaming agent, 0.01%-0.1% of a coloring agent and the balance of base oil. The aviation hydraulic oil composition disclosed by the invention has excellent low-temperature fluidity, high-temperature stability, anti-rust property and rubber compatibility, particularly has extremely good high-low temperature viscosity stability, and can ensure that an aircraft landing gear and a hydraulic system smoothly operate in an environment with relatively large high-low temperature change amplitude.

Description

Technical Field

[0001] This invention belongs to the field of special oils for aircraft hydraulic systems, specifically relating to an aviation hydraulic oil composition, its preparation method, and its application. Background Technology

[0002] Ambient temperature variations significantly impact the operating status of aircraft hydraulic systems. At lower temperatures, oil viscosity is higher, resulting in greater damping force and reduced hydraulic efficiency. Conversely, at higher temperatures, oil viscosity is lower, leading to less damping force and decreased system stability. Therefore, the oil needs a high viscosity index to maintain stable viscosity in environments with wide temperature variations. A smaller viscosity variation range in high and low temperature environments results in smaller damping force variations, leading to higher hydraulic system efficiency and ultimately improved equipment efficiency. Aviation hydraulic oil frequently comes into contact with rubber seals during operation, requiring excellent rubber compatibility. It also needs to come into contact with metals during operation, necessitating good rust prevention. Furthermore, the hydraulic systems, such as aircraft landing gear, generate heat during operation, making the oil highly susceptible to oxidation at high temperatures, thus requiring excellent oxidation resistance.

[0003] Chinese invention patent application CN115386411A discloses a method for preparing ultra-low temperature aviation hydraulic oil. The method includes the following steps: S1: preparation of base oil; S2: blending with additives and filtering; and S3: filling. In step S1, a distillation process using an atmospheric and vacuum distillation unit is employed. The distillation tower top temperature is 160-180℃, the distillation tower bottom temperature is 250-260℃, the side stream extraction temperature is 200-210℃, and the side stream stripping tower steam flow rate is 200-250 kg / h. This invention uses crude oil from Tarim, Turpan-Hami, and Yumen to prepare the base oil, which exhibits excellent low-temperature fluidity and oxidation resistance. However, the preparation method is relatively complex.

[0004] Chinese invention patent application CN115305137A discloses an ultra-low temperature aviation hydraulic oil and its application. This ultra-low temperature aviation hydraulic oil comprises: 100 parts by weight of base oil, 8-10 parts by weight of pour point depressant and viscosity improver, 1-2 parts by weight of antioxidant, 2-3 parts by weight of anti-wear agent, and 0.01-0.02 parts by weight of anti-foaming agent. The base oil is obtained by distillation of 68-74 parts by weight of Tarim crude oil, 19-25 parts by weight of Yumen crude oil, and 5-13 parts by weight of Turpan-Hami heavy oil to obtain suitable fractions. It possesses excellent low-temperature fluidity, oxidation resistance, and rust prevention properties, but the raw material cost is relatively high.

[0005] During operation, aviation hydraulic oil experiences large temperature fluctuations and frequent contact with metal materials and rubber seals, which can easily lead to poor low-temperature fluidity, deformation of rubber seals, and high-temperature oxidation.

[0006] After years of technological accumulation, the base oil hydrotreating process technology, such as the base oil hydrotreating isomerization dewaxing process, has become increasingly mature in China, and the performance of additives has also been greatly improved. This has provided the technical conditions for developing aviation hydraulic oils, and there is an urgent need to develop high-performance and low-cost aviation hydraulic oil products. Summary of the Invention

[0007] To address the problems of complex preparation methods and high preparation costs in existing technologies, this invention provides an aviation hydraulic oil composition, its preparation method, and its application.

[0008] This invention is achieved through the following technical solution:

[0009] An aviation hydraulic oil composition, wherein the raw materials of the aviation hydraulic oil composition, by mass percentage, include: 15%-20% viscosity index improver, 0.01%-1% antioxidant, 0.01%-1% anti-wear agent, 0.1%-2.0% rust inhibitor, 0.01%-0.1% antifoaming agent, 0.01%-0.1% colorant, and the balance base oil.

[0010] Preferably, the kinematic viscosity of the base oil at 40°C is ≥2 mm. 2 / s, open flash point ≥100℃, pour point ≥-60℃.

[0011] More preferably, the base oil is No. 3 grinding oil.

[0012] Preferably, the viscosity index improver is polymethacrylate, the polymethacrylate having a molecular weight of 250,000-350,000 and a side chain with 20-30 carbon atoms.

[0013] Preferably, the kinematic viscosity of the antioxidant is 120-140 mm. 2 / s, the synergistic effect of rotating oxygen bomb is ≥600min, and the synergistic effect of oxidation test life is ≥6000h.

[0014] More preferably, the antioxidant is octylbutyldiphenylamine, selected from any one of L57, T501 and L135.

[0015] Preferably, the anti-wear agent is tricresyl phosphate, with a phosphorus content of not less than 13%, a wear scar diameter of not more than 0.5 mm, a Pb value of not less than 600 N, and the type is selected from any one of T306, IR232 and T204.

[0016] Preferably, the rust inhibitor is dodecenylsuccinic acid, with a total acid value of 292 mg KOH / g and a pH value of 4.7, and the type is selected from any one of T746, NA-SUL729 and T702.

[0017] Preferably, the antifoaming agent is a No. 1 composite antifoaming agent.

[0018] Preferably, the dye is Sudan Red.

[0019] The present invention also relates to a method for preparing the above-mentioned aviation hydraulic oil composition, comprising the following steps:

[0020] The base oil, viscosity index improver, antioxidant, anti-wear agent, rust inhibitor, antifoaming agent and colorant are mixed and stirred to obtain the aviation hydraulic oil composition.

[0021] Preferably, the stirring temperature is 55-65℃ and the stirring time is 1-2 hours.

[0022] The present invention also relates to the application of the above-mentioned aviation hydraulic oil composition in the preparation of aviation hydraulic oil.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The present invention is simple to prepare, and the resulting aviation hydraulic oil composition has excellent low-temperature fluidity, high-temperature stability, rust prevention and rubber compatibility. In particular, it has excellent high and low temperature viscosity stability, which can ensure the smooth operation of aircraft landing gear and hydraulic system in environments with large temperature variations. Detailed Implementation

[0025] The present invention will be further described in detail below with reference to specific embodiments. The following embodiments are not intended to limit the present invention, but only to illustrate the present invention. Unless otherwise specified, the experimental methods used in the following embodiments are generally performed under conventional conditions. Unless otherwise specified, the materials and reagents used in the following embodiments are commercially available.

[0026] No. 3 grinding oil (paraffin-based low viscosity base oil), manufactured by Karamay Petrochemical Company;

[0027] #1 composite antifoaming agent, manufactured by Jinzhou Runda Chemical Co., Ltd.

[0028] Antioxidants L57 and L135 are manufactured by BASF Group; antioxidant T501 is manufactured by Shandong Linyi Sanfeng Chemical Co., Ltd.

[0029] The manufacturers of anti-wear agents T306 and T232 are Shenyang Feida Chemical Oil Products Co., Ltd.; the manufacturer of anti-wear agent T204 is Xinxiang Ruifeng New Materials Co., Ltd.

[0030] Rust inhibitors T746 and T702 are manufactured by Xinxiang Ruifeng New Materials Co., Ltd.; rust inhibitor NA-SUL729 is manufactured by King Industries.

[0031] Example 1

[0032] An aviation hydraulic oil composition, the raw materials and the mass percentage of each raw material are shown in Table 1.

[0033] Table 1. Raw materials and content of aviation hydraulic oil composition in Example 1.

[0034] raw material Name / Model content(%) base oil No. 3 Grinding Oil 84.86 Viscosity index improver Polymethyl methacrylate (viscosity index improver T602) 15 antioxidants Octylbutyldiphenylamine (antioxidant L57) 0.01 anti-wear agent Tricresol phosphate (anti-wear agent T306) 0.01 Rust inhibitor Dodecenyl succinic acid (rust inhibitor T746) 0.1 Antifoaming agent #1 Compound Antifoaming Agent 0.01 dye Sudan I 0.01

[0035] The preparation method of the above-mentioned aviation hydraulic oil composition is as follows:

[0036] The base oil, viscosity index improver, antioxidant, anti-wear agent, rust inhibitor, antifoaming agent and colorant are mixed and stirred at 60°C for 1.5 hours to obtain the aviation hydraulic oil composition.

[0037] Example 2

[0038] An aviation hydraulic oil composition, the raw materials and the mass percentage of each raw material are shown in Table 2.

[0039] Table 2. Raw materials and content of aviation hydraulic oil composition in Example 2.

[0040] raw material Name / Model content(%) base oil No. 3 Grinding Oil 79.72 Viscosity index improver Polymethyl methacrylate (viscosity index improver T602) 18.3 antioxidants Octylbutyldiphenylamine (antioxidant T501) 0.4 anti-wear agent Tricresol phosphate (anti-wear agent IR232) 0.5 Rust inhibitor Dodecenyl succinic acid (rust inhibitor NA-SUL729) 1.0 Antifoaming agent #1 Compound Antifoaming Agent 0.04 dye Sudan I 0.04

[0041] The preparation method of the above-mentioned aviation hydraulic oil composition is as follows:

[0042] The base oil, viscosity index improver, antioxidant, anti-wear agent, rust inhibitor, antifoaming agent and colorant are mixed and stirred at 65°C for 1 hour to obtain the aviation hydraulic oil composition.

[0043] Example 3

[0044] An aviation hydraulic oil composition, the raw materials and the mass percentage of each raw material are shown in Table 3.

[0045] Table 3. Raw materials and content of aviation hydraulic oil composition in Example 3.

[0046] raw material Name / Model content(%) base oil No. 3 Grinding Oil 76.42 Viscosity index improver Polymethyl methacrylate (viscosity index improver T602) 20 antioxidants Octylbutyldiphenylamine (antioxidant L135) 0.8 anti-wear agent Tricresol phosphate (anti-wear agent T204) 0.8 Rust inhibitor Dodecenyl succinic acid (rust inhibitor T702) 1.8 Antifoaming agent #1 Compound Antifoaming Agent 0.09 dye Sudan I 0.09

[0047] The preparation method of the above-mentioned aviation hydraulic oil composition is as follows:

[0048] The base oil, viscosity index improver, antioxidant, anti-wear agent, rust inhibitor, antifoaming agent and colorant are mixed and stirred at 55°C for 2 hours to obtain the aviation hydraulic oil composition.

[0049] The performance test results and test reference standards of the aviation hydraulic oil compositions prepared in Examples 1-3 are shown in Table 4.

[0050] Table 4 Performance Test Results

[0051]

[0052]

[0053] As shown in Table 4, the kinematic viscosity of the aviation hydraulic oil composition in Example 1 at -40°C is only 278.3 mm. 2 With a viscosity index as high as 368, the aviation hydraulic oil has excellent low-temperature fluidity and an extremely high viscosity index, which can effectively ensure the smooth operation of the aircraft landing gear hydraulic system in low-temperature environments.

[0054] Comparative Example 1

[0055] The only difference between this comparative example and Example 1 is the amount of raw materials added, as shown in Table 5.

[0056] Table 5. Raw materials and their contents in Comparative Example 1: Aviation hydraulic oil composition.

[0057] raw material Name / Model content(%) base oil No. 3 Grinding Oil 77.86 Viscosity index improver Polymethyl methacrylate (viscosity index improver T602) 22 antioxidants Octylbutyldiphenylamine (antioxidant L57) 0.01 anti-wear agent Tricresol phosphate (anti-wear agent T306) 0.01 Rust inhibitor Dodecenyl succinic acid (rust inhibitor T746) 0.1 Antifoaming agent #1 Compound Antifoaming Agent 0.01 dye Sudan I 0.01

[0058] Comparative Example 2

[0059] The only difference between this comparative example and Example 1 is the base oil. The base oil in this comparative example is W1-100 light white oil. See Table 6 for details.

[0060] Table 6. Raw materials and their contents in the aviation hydraulic oil composition of Comparative Example 2.

[0061]

[0062]

[0063] Comparative Examples 1-2 and commercially available products were tested using the same testing methods as Examples 1-3, and the results are shown in Table 7.

[0064] Table 7 Performance Test Results

[0065]

[0066] As can be seen from the performance data of the aviation hydraulic oil composition in the examples, the aviation hydraulic oil composition of the present invention has excellent high and low temperature stability, rust prevention and rubber compatibility, especially excellent low temperature flow performance, and the oil can meet all the requirements of OEM quality indicators.

[0067] The above detailed description is a specific description of one of the feasible embodiments of the present invention. This embodiment is not intended to limit the patent scope of the present invention. All equivalent implementations or modifications that do not depart from the present invention should be included within the scope of the technical solution of the present invention.

Claims

1. An aviation hydraulic oil composition, characterized in that, The raw materials of the aviation hydraulic oil composition, by weight percentage, include: 15%-20% viscosity index improver, 0.01%-1% antioxidant, 0.01%-1% anti-wear agent, 0.1%-2.0% rust inhibitor, 0.01%-0.1% anti-foaming agent, 0.01%-0.1% colorant, and the balance base oil.

2. The aviation hydraulic oil composition according to claim 1, characterized in that, Base oil kinematic viscosity at 40°C ≥2 mm 2 / s, open flash point ≥100℃, pour point ≥-60℃.

3. The aviation hydraulic oil composition according to claim 1, characterized in that, The viscosity index improver is polymethyl methacrylate, which has a molecular weight of 250,000-350,000 and a side chain with 20-30 carbon atoms.

4. The aviation hydraulic oil composition according to claim 1, characterized in that, The kinematic viscosity of the antioxidant is 120-140 mm. 2 / s, the synergistic effect of rotating oxygen bomb is ≥600min, and the synergistic effect of oxidation test life is ≥6000h.

5. The aviation hydraulic oil composition according to claim 4, characterized in that, The antioxidant is octylbutyldiphenylamine, and the type is selected from any one of L57, T501 and L135.

6. The aviation hydraulic oil composition according to claim 1, characterized in that, The anti-wear agent is tricresyl phosphate, and the type is selected from any one of T306, IR232 and T204.

7. The aviation hydraulic oil composition according to claim 1, characterized in that, The rust inhibitor is dodecenyl succinic acid, and the model is selected from any one of T746, NA-SUL729 and T702.

8. The aviation hydraulic oil composition according to claim 1, characterized in that, The antifoaming agent is No. 1 composite antifoaming agent.

9. The aviation hydraulic oil composition according to claim 1, characterized in that, The dye is Sudan Red.

10. A method for preparing an aviation hydraulic oil composition according to any one of claims 1-9, characterized in that, Includes the following steps: The base oil, viscosity index improver, antioxidant, anti-wear agent, rust inhibitor, antifoaming agent and colorant are mixed and stirred to obtain the aviation hydraulic oil composition.

11. The preparation method according to claim 10, characterized in that, The stirring temperature is 55-65℃, and the stirring time is 1-2 hours.

12. The use of the aviation hydraulic oil composition according to any one of claims 1-9 in the preparation of aviation hydraulic oil.

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