Ashless piston type aero-engine lubricating oil composition and preparation method thereof

Abstract

The invention discloses an ash-free piston type aero-engine lubricating oil composition and a preparation method thereof, and the ash-free piston type aero-engine lubricating oil composition mainly comprises the following components by weight: 80-90 parts of a base oil mixture; 6.0 to 9.0 parts of a viscosity index improver; 3.0 to 6.0 parts of a succinimide ashless dispersant; 0.5 to 2.0 parts of an ashless antioxidant; 0.01 to 0.2 part of a benzotriazole metal passivator; 0.5 to 3.0 parts of a phosphorus-containing anti-wear agent; and 10 to 100 ppm of an anti-foaming agent. The ash-free piston type aero-engine lubricating oil composition has good oxidation resistance, reduces oil sludge and acidic substances, ensures system cleanness, further reduces engine faults and prolongs the service life of an oil product. And physical and chemical performance tests of the lubricating oil composition all meet SAE J1899 technical requirements, and the lubricating oil composition passes a single-cylinder engine bench test.

Description

Technical Field

[0001] The invention relates to an ashless piston aircraft engine lubricating oil composition and a preparation method thereof. Background Art

[0002] The aviation industry is a strategic high-tech industry, and promoting the localization of aviation engine lubricants is also an important part of the strategy of building an aviation power. At present, the main international standards for aviation piston engine lubricants are SAE J1966 and SAE J1899 formulated by SAE (Society of Automotive Engineers). SAE J1966 is a technical standard for dispersant-free mineral lubricants suitable for four-stroke reciprocating aviation piston engines, including physical and chemical properties and procedure VIII engine bench tests. SAE J1899 is a technical standard for ashless dispersant lubricants suitable for four-stroke reciprocating aviation piston engines, including physical and chemical properties, procedure VIII engine bench tests, 150h Lycoming engine endurance tests and 500 hours of flight evaluation tests.

[0003] At present, most of the products on the market meet the SAEJ1899 specification. The product viscosity levels include single-grade oils and multi-grade oils such as 30, 40, 50, and 60. The main products are EXXON AVIATION OIL 20W-50 and AERO SHELLW15W-50, both of which are semi-synthetic products. There are no domestically produced aviation piston engine lubricant products that have obtained airworthiness certification in China. In 2020, my country's Civil Aviation Airworthiness Certification Center formulated a series of aviation engine oil technical specifications, and independently established a full set of lubricant analysis and testing methods, including a full set of test and evaluation methods for piston aviation engine oil. The localization research on four-stroke piston aviation engine oil has initially met the testing conditions. Summary of the invention

[0004] The present invention is made in order to improve the oxidation resistance of engine lubricating oil, reduce sludge and acidic substances in the lubricating oil, ensure system cleanliness, make the engine lubricating oil meet the SAEJ1899 specification requirements, and pass the single-cylinder engine bench test.

[0005] As a first aspect of the present invention, it relates to an ashless piston aircraft engine lubricating oil composition, which mainly comprises the following components by weight:

[0006] 80-90 parts of base oil mixture;

[0007] 6.0-9.0 parts of viscosity index improver;

[0008] 3.0-6.0 parts of succinimide ashless dispersant;

[0009] Ashless antioxidant 0.5-2.0 parts;

[0010] 0.01-0.2 parts of benzotriazole metal passivator;

[0011] 0.5-3.0 parts of phosphorus antiwear agent;

[0012] Antifoaming agent 10-100ppm.

[0013] In one or some optional embodiments, the ashless antioxidant is a diisooctyl diphenylamine antioxidant.

[0014] In one or some optional embodiments, the succinimide ashless dispersant does not contain boron.

[0015] In one or some optional embodiments, the base oil mixture is prepared by mixing polyalphaolefin (PAO) with Group III VHVI mineral oil.

[0016] In one or some optional embodiments, the phosphorus-containing antiwear agent is tricresyl phosphate.

[0017] In one or some optional embodiments, the viscosity index improver is an ethylene-propylene copolymer viscosity index improver.

[0018] In one or some optional embodiments, the average molecular weight of the ethylene-propylene copolymer viscosity index improver is 30,000-50,000.

[0019] In one or some optional embodiments, the anti-foaming agent is methyl silicone oil.

[0020] As a second aspect of the present invention, it relates to a method for preparing the above-mentioned ashless piston aircraft engine lubricating oil composition, comprising:

[0021] The base oil, viscosity index improver, succinimide ashless dispersant, ashless antioxidant, benzotriazole metal passivator, phosphorus anti-wear agent and anti-foaming agent are uniformly mixed according to weight ratio.

[0022] In one or some optional embodiments, the method specifically includes:

[0023] Add base oil, viscosity index improver, succinimide ashless dispersant, ashless antioxidant, benzotriazole metal passivator, phosphorus antiwear agent and antifoaming agent into a blending kettle according to weight ratio, heat up to 60-70°C, stir for 2-4 hours under normal pressure, and filter to obtain an ashless piston aircraft engine oil composition.

[0024] The present invention optimizes the composition and ratio of different additives in lubricating oil, optimizes the ratio of ashless dispersant and antioxidant, and forms an ashless anti-corrosion aviation engine oil composition. The present invention prepares an ashless engine oil composition by rationally proportioning phosphorus-containing antiwear agent, ashless antioxidant and ashless dispersant. The engine oil composition has good antioxidant properties, greatly reduces sludge and acidic substances, ensures system cleanliness, thereby reducing the occurrence of engine failures and extending the service life of oil products. The physical and chemical performance tests of the ashless piston aircraft engine lubricating oil composition all meet the SAEJ1899 technical requirements and pass the single-cylinder engine bench test.

[0025] The succinimide ashless dispersant used in the present invention has excellent thermal stability and high-temperature dispersion ability. Multiple succinimides are assembled to form a colloid, which can prevent the oxidation and condensation of oil products, further reduce the formation of engine deposits, and can wash off the paint film and carbon deposits adsorbed on engine parts, disperse them in the oil, and keep the engine surface clean. The present invention uses tricresol phosphate as a phosphorus-containing anti-wear agent, which has good anti-wear performance, can well inhibit the influence of deposits generated by the combustion of leaded fuel on the anti-wear performance of lubricating oil, and also has a significant effect on the wear protection of cam tappets. The ashless antioxidant used in the present invention has a good ability to inhibit the oxidation of engine oil, and has a significant effect on preventing the increase of oil viscosity. DETAILED DESCRIPTION

[0026] The following is a detailed description of the embodiments of the present invention: The embodiments of the present invention are implemented on the premise of the technical solution of the present invention, and detailed implementation methods and processes are given, but the protection scope of the present invention is not limited to the following embodiments. The process parameters for which specific conditions are not specified in the following embodiments are generally based on conventional conditions.

[0027] The endpoints and any values ​​of the ranges disclosed in the present invention are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in the present invention.

[0028] It should be noted that the raw materials and their sources used in the examples of the present invention are shown in Table 1 below.

[0029] Table 1 Experimental raw materials

[0030]

[0031]

[0032] Example 1

[0033] 70 kg of base oil mixture (polyalphaolefin (PAO): Class III VHVI mineral oil = 2:5), 6.4 kg of ethylene-propylene copolymer viscosity index improver, 1.2 kg of succinimide ashless dispersant, 1.4 kg of ashless antioxidant, 0.2 kg of benzotriazole metal passivator, 0.8 kg of tricresol phosphate and 10 g of antifoaming agent were added into a blending kettle, the temperature was raised to 70°C, stirred at normal pressure for 4 hours, and then filtered to obtain an ashless piston aircraft engine lubricating oil composition.

[0034] Example 2

[0035] 17.26 kg of base oil mixture (polyalphaolefin (PAO): Class III VHVI mineral oil = 2:5), 1.5 kg of ethylene-propylene copolymer viscosity index improver, 0.5 kg of succinimide ashless dispersant, 0.5 kg of ashless antioxidant, 40 g of benzotriazole metal passivator, 0.2 kg of tricresyl phosphate and 2 g of antifoaming agent were added into a blending kettle, the temperature was raised to 65°C, stirred for 3 hours at normal pressure, and then filtered to obtain an ashless piston aircraft engine lubricating oil composition.

[0036] Example 3

[0037] 142 kg of base oil mixture (polyalphaolefin (PAO): Class III VHVI mineral oil = 2:5), 12.8 kg of ethylene-propylene copolymer viscosity index improver, 2.5 kg of succinimide ashless dispersant, 2.8 kg of ashless antioxidant, 0.4 kg of benzotriazole metal passivator, 1.5 kg of tricresyl phosphate and 20 g of antifoaming agent were added into a blending kettle, the temperature was raised to 70°C, stirred at normal pressure for 4 hours, and then filtered to obtain an ashless piston aircraft engine lubricating oil composition.

[0038] Test Example 1

[0039] The physical and chemical properties of the ashless piston aircraft engine lubricating oil compositions prepared in Examples 1-3 were tested, and the test results are shown in Table 2.

[0040] Table 2 Physical and chemical properties of the lubricating oil compositions in Examples 1-3

[0041]

[0042]

[0043] From the analysis in Table 2, it can be seen that the analysis results of the ashless piston aircraft engine lubricating oil compositions prepared in Examples 1-3 are stable, and the physical and chemical values ​​of different batches all meet the requirements of the SAE J1899 standard.

[0044] Test Example 2

[0045] The ashless piston aircraft engine lubricating oil compositions prepared in Examples 1-3 were subjected to single cylinder engine bench tests. The test results are shown in Table 2.

[0046] Table 2 Single cylinder engine bench test data of lubricating oil compositions in Examples 1-3

[0047]

[0048] From the analysis of Table 2, it can be seen that the single-cylinder engine bench test data of the ashless piston aircraft engine lubricating oil composition in Examples 1 to 3 all meet the control index requirements and pass the single-cylinder engine bench test.

[0049] Although the specific embodiments of the present invention have been described in detail, it will be understood by those skilled in the art. According to all the teachings disclosed, various modifications and replacements can be made to those details, and these changes are all within the protection scope of the present invention. The full scope of the present invention is given by the attached claims and any equivalents thereof.

Claims

1. An ashless piston aircraft engine lubricating oil composition, characterized in that: The lubricating oil composition mainly comprises the following components by weight: 80-90 parts of base oil; 6.0-9.0 parts of viscosity index improver; 3.0-6.0 parts of succinimide ashless dispersant; Ashless antioxidant 0.5-2.0 parts; 0.01-0.2 parts of benzotriazole metal passivator; 0.5-3.0 parts of phosphorus antiwear agent; Antifoaming agent 10-100ppm.

2. The lubricating oil composition according to claim 1, characterized in that The ashless antioxidant is a diisooctyl diphenylamine antioxidant.

3. The lubricating oil composition according to claim 1, characterized in that The succinimide ashless dispersant does not contain boron element.

4. The lubricating oil composition according to claim 1, characterized in that The base oil mixture is a mixture of polyalphaolefin and group III VHVI mineral oil.

5. The lubricating oil composition according to claim 1, characterized in that The phosphorus-containing anti-wear agent is tricresyl phosphate.

6. The lubricating oil composition according to claim 1, wherein The viscosity index improver is an ethylene-propylene copolymer viscosity index improver.

7. The lubricating oil composition according to claim 1, characterized in that The average molecular weight of the ethylene-propylene copolymer viscosity index improver is 30,000-50,000.

8. The lubricating oil composition according to claim 1, characterized in that The anti-foaming agent is methyl silicone oil.

9. A method for preparing the ashless piston aircraft engine lubricating oil composition according to any one of claims 1 to 8, characterized in that: The method includes: The base oil, viscosity index improver, succinimide ashless dispersant, ashless antioxidant, benzotriazole metal passivator, phosphorus anti-wear agent and anti-foaming agent are uniformly mixed according to weight ratio.

10. The method according to claim 9, characterized in that The method specifically comprises: Add base oil, viscosity index improver, succinimide ashless dispersant, ashless antioxidant, benzotriazole metal passivator, phosphorus antiwear agent and antifoaming agent into a blending kettle according to weight ratio, heat up to 60-70°C, stir for 2-4 hours under normal pressure, and filter to obtain an ashless piston aircraft engine oil composition.

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