Special lubricating oil composition for wet type electric drive of heavy-load commercial vehicle and application of special lubricating oil composition

Abstract

The invention relates to a special lubricating oil composition for wet electric drive of a heavy-load commercial vehicle and application of the special lubricating oil composition. Based on 100 parts by weight of the lubricating oil composition, the lubricating oil composition comprises the following components: a) 60-90 parts by weight of base oil; b) 0-20 parts by weight of a viscosity index improver; c) 0.5 to 6.0 parts by weight of an extreme pressure anti-wear agent; d) 0.2 to 5.0 parts by weight of a friction modifier; e) 0.1-1.0 part by weight of a pour point depressant; f) 0.1 to 3.0 parts by weight of an antioxidant; g) 0.1-5.0 parts by weight of an antirust agent; h) 0.01 to 1 part by weight of an anti-foaming agent; the lubricating oil composition has a breakdown voltage of at least 50 kV at 30 DEG C.

Description

Technical Field

[0001] The present invention belongs to the technical field of lubricating oils, and in particular relates to a lubricating oil composition specially used for wet electric drive of heavy-duty commercial vehicles and an application thereof. Background Art

[0002] At present, some new energy heavy-duty commercial vehicles adopt the design of motor and reducer split, but its axial size is large, occupying more space, the weight of the transmission assembly is also large, and the increase of the input shaft component of the reducer increases the failure point, which will reduce the overall efficiency of the electric drive assembly. Therefore, the integrated system of motor and transmission has become the main development direction, which can improve the power and economy of new energy commercial vehicles, but this has brought new challenges to the oil used in electric drive.

[0003] At present, the performance of traditional commercial vehicle transmission oil can meet the GL-4 specification or GL-5 specification, but its breakdown voltage is relatively low (only about 40 to 42 kV). Compared with traditional commercial vehicle transmission oil, new energy heavy-duty commercial vehicle integrated system lubricant (also known as wet electric drive special oil or wet electric drive special lubricant) needs to be lubricated and cooled in a working environment with higher temperature, higher system voltage, more pad components and higher speed. Therefore, wet electric drive special oil is required to maintain good corrosion resistance, wear resistance and long life. On the basis of performance, it should also have excellent low-temperature starting performance, heat transfer performance, electrical performance, insulation material compatibility and load-bearing performance under longer continuous peak power. Therefore, there are currently no oils that meet these requirements on the market, nor are there any related patent reports on oils that meet these requirements. Summary of the invention

[0004] In view of the above technical problems, the purpose of the present invention is to provide a special lubricating oil composition for wet electric drive of heavy-duty commercial vehicles, which has good low-temperature fluidity, excellent electrical and thermal properties, good compatibility with insulating materials, and excellent copper corrosion protection and load-bearing capacity, and its application.

[0005] A first aspect of the present invention provides a lubricating oil composition, which comprises the following components based on 100 parts by weight of the lubricating oil composition:

[0006] a) 60 to 90 parts by weight of base oil;

[0007] b) 0 to 20 parts by weight of a viscosity index improver;

[0008] c) 0.5 to 6.0 parts by weight of an extreme pressure anti-wear agent;

[0009] d) 0.2 to 5.0 parts by weight of a friction modifier;

[0010] e) 0.1 to 1.0 parts by weight of a pour point depressant;

[0011] f) 0.1 to 3.0 parts by weight of an antioxidant;

[0012] g) 0.1 to 5.0 parts by weight of a rust inhibitor;

[0013] h) 0.01 to 0.1 parts by weight of an antifoaming agent;

[0014] The lubricating oil composition has a breakdown voltage of at least 50 kV at 30°C.

[0015] Preferably, based on 100 parts by weight of the lubricating oil composition, the lubricating oil composition consists of the following components:

[0016] a) 82 to 90 parts by weight of base oil;

[0017] b) 0 to 8 parts by weight of a viscosity index improver;

[0018] c) 2.5 to 5.0 parts by weight of an extreme pressure antiwear agent;

[0019] d) 2.0 to 5.0 parts by weight of a friction modifier;

[0020] e) 0.1 to 1.0 parts by weight of a pour point depressant;

[0021] f) 0.1 to 2.0 parts by weight of an antioxidant;

[0022] g) 0.1 to 2.0 parts by weight of a rust inhibitor;

[0023] h) 0.01 to 0.06 parts by weight of an antifoaming agent.

[0024] Preferably, the base oil is mineral oil and / or synthetic base oil;

[0025] More preferably, the mineral oil is selected from Group III mineral oil, and the synthetic base oil is selected from at least one of synthetic oil produced by Fischer-Tropsch reaction, poly-alpha-olefin PAO synthetic oil, and hyperbranched polyethylene synthetic oil, or a combination thereof;

[0026] More preferably, the kinematic viscosity of the synthetic oil produced by the Fischer-Tropsch reaction at 100°C is 2.0 to 100.0 mm 2 / s, the kinematic viscosity of the poly-alpha-olefin PAO synthetic oil at 100°C is 4.0-150.0 mm 2 / s, the kinematic viscosity of the hyperbranched polyethylene synthetic oil at 100°C is 2.0 to 100.0 mm 2 / s.

[0027] Preferably, the viscosity index improver is selected from at least one of polymethacrylate copolymers, ethylene-propylene copolymers, hydrogenated styrene-diene copolymers, or a combination thereof, preferably polymethacrylate copolymers.

[0028] Preferably, the extreme pressure anti-wear agent is selected from at least one of organic phosphates, acidic phosphate ammonium salts, phosphoric acid amides and alkyl phosphites or a combination thereof, preferably acidic phosphate ammonium salts.

[0029] Preferably, the friction modifier is selected from at least one of ethoxylated amines, fatty acid glycerides, benzotriazole fatty amine salts, or a combination thereof.

[0030] Preferably, the pour point depressant is selected from polymethacrylates.

[0031] Preferably, the antioxidant is selected from phenolic antioxidants and / or amine antioxidants.

[0032] Preferably, the rust inhibitor is selected from at least one of alkenyl succinates, organic phosphate amine salts, benzotriazole derivatives and thiadiazole derivatives, or a combination thereof.

[0033] Preferably, the antifoaming agent is selected from at least one of dimethyl silicone oil / oil ester antifoaming agent and polyacrylate antifoaming agent or a combination thereof.

[0034] Preferably, the lubricating oil composition has one or more of the following characteristics:

[0035] The kinematic viscosity of the lubricating oil composition at 100° C. is 5.0 to 11.0 mm 2 / s, pour point not higher than -40℃;

[0036] The Brookfield viscosity of the lubricating oil composition at -40°C is ≤110000 mPa·s, preferably ≤90000 mPa·s;

[0037] The lubricating oil composition has a corrosion grade of not less than 1b in copper sheet corrosion;

[0038] The lubricating oil composition has a specific heat capacity of 2.10 to 2.30 J / (g·K) at 30°C;

[0039] The lubricating oil composition has a specific heat capacity of 2.34 to 2.50 J / (g·K) at 80°C;

[0040] The heat transfer coefficient of the lubricating oil composition at 30° C. is 154 to 160 mW / (m·K);

[0041] The heat transfer coefficient of the lubricating oil composition at 80° C. is 144 to 150 mW / (m·K).

[0042] A second aspect of the present invention provides an application of the above-mentioned lubricating oil composition in the field of mechatronic transmission assemblies of new energy commercial vehicles, wherein the mechatronic transmission assemblies of new energy commercial vehicles include motors, electronic controls and reduction gearboxes / transmission boxes.

[0043] Beneficial effects of the present invention:

[0044] 1. The lubricating oil composition of the present invention has a relatively low low-temperature kinematic viscosity and pumping viscosity; the Brookfield viscosity at -40°C is more preferably less than 80,000 mPa·s, so as to ensure that the oil product has excellent low-temperature fluidity and smooth start-up under ultra-low temperature conditions;

[0045] 2. The lubricating oil composition of the present invention has a high bearing capacity of the gear shaft, which can meet the lubrication needs of the rear axle gear of the vehicle, and is particularly suitable for a system with an oil pump lubrication in the gear box to ensure the transportability of the oil at low temperatures and provide reliable lubrication for the gear system;

[0046] 3. The lubricating oil composition of the present invention has excellent copper corrosion protection ability and can be in direct contact with the parts containing exposed copper in the motor system for lubrication and cooling;

[0047] 4. The lubricating oil composition of the present invention has good specific heat capacity and heat transfer coefficient within 30-150°C, confirming reliable heat capacity and heat conduction efficiency;

[0048] 5. The breakdown voltage of the lubricating oil composition of the present invention at 30° C. is 50 to 60 kV (e.g., as high as 57 kV), which can meet the electrical insulation performance requirements of the electric drive system. DETAILED DESCRIPTION

[0049] The present invention is further described below by the following embodiments. It should be understood that the following embodiments are only used to illustrate the present invention, but not to limit the present invention.

[0050] In the present invention, "parts by weight" should be interpreted as relative parts by weight, which can be any weight unit, such as but not limited to kilograms, kilograms, grams, pounds and other weight units. For example, 90 parts by weight of base oil means 90 kilograms of base oil or 90 pounds of base oil.

[0051] In one embodiment of the present invention, the lubricating oil composition specifically for wet electric drive of heavy-duty commercial vehicles (hereinafter referred to as lubricating oil composition) comprises the following components: base oil, optional viscosity index improver, extreme pressure anti-wear agent, friction modifier, pour point depressant, antioxidant, rust inhibitor and anti-foaming agent.

[0052] In one embodiment of the present invention, based on 100 parts by weight of the lubricating oil composition, the content of the base oil is 60 to 90 parts by weight, preferably 82 to 90 parts by weight, and more preferably 88 to 90 parts by weight. The base oil is a mineral oil and / or a synthetic base oil. The mineral oil is selected from Class III mineral oil. The synthetic base oil is selected from one or more of the synthetic oil made by Fischer-Tropsch reaction, poly α-olefin PAO synthetic oil, and hyperbranched polyethylene synthetic oil. The kinematic viscosity of the base oil at 100°C is 2.0 to 150.0 mm 2 / s, preferably 2.0 to 100.0 mm 2 For example, the kinematic viscosity of the synthetic oil produced by the Fischer-Tropsch reaction at 100°C is 2.0 to 100.0 mm 2 The kinematic viscosity of the poly-alpha-olefin PAO synthetic oil at 100°C is 4.0 to 150.0 mm 2 The kinematic viscosity of the hyperbranched polyethylene synthetic oil at 100°C is 2.0 to 100.0 mm 2 / s. Specifically, the base oil used in the present invention can adopt relevant products commercially available on the market, including but not limited to: one or more of AD 3CST, AD 4CST, AD6CST, Yubase3, Yubase 4, Yubase 6, ICCSYN 3, ICCSYN 4, ICCSYN 6, ICCSYN10, PAO4, PAO6, PAO100, PAO150, ETO2, ETO3, ETO4, ETO6, ETO8, ETO10, ETO40 and ETO100.

[0053] In one embodiment of the present invention, the lubricating oil composition further comprises a viscosity index improver. Wherein, based on 100 parts by weight of the lubricating oil composition, the amount of the viscosity index improver added is 0 to 20 parts by weight, preferably 0 to 8 parts by weight, and more preferably 0 to 2 parts by weight. Preferably, the viscosity index improver is selected from polymethacrylate copolymers. Specifically, the viscosity index improver used in the present invention adopts commercially available related products on the market, including but not limited to: VISCOPLEX 12-072, VISCOPLEX 12-075 and VISCOPLEX 12-100 produced by Evonik, ACLUBE 3040 of Sanyo Corporation of Japan and other polymethacrylate copolymer products.

[0054] In one embodiment of the present invention, based on 100 parts by weight of the lubricating oil composition, the addition amount of the extreme pressure anti-wear agent is 0.5 to 6.0 parts by weight, preferably 2.5 to 5.0 parts by weight. Preferably, the extreme pressure anti-wear agent includes an acidic ammonium phosphate salt, etc. Specifically, the extreme pressure anti-wear agent used in the present invention can adopt commercially available related products on the market, including but not limited to: T308 of Shenyang Hualun Lubricating Oil Additive Co., Ltd. and Vanlube 672E of Vanderbilt Company and other ammonium phosphate salt products.

[0055] In one embodiment of the present invention, based on 100 parts by weight of the lubricating oil composition, the friction modifier is added in an amount of 0.2 to 5.0 parts by weight, preferably 2.0 to 5.0 parts by weight. Preferably, the friction modifier is selected from one or more of 2-ethoxyamine, oleic acid glyceride, and benzotriazole fatty amine salt. Specifically, the friction modifier used in the present invention adopts commercially available related products on the market, including but not limited to: ETHOMEEN T / 13 of Nouryon; oleic acid glyceride of Hai'an Guoli Chemical; T406 of Kunhou Chemical Co., Ltd., etc.

[0056] In one embodiment of the present invention, the pour point depressant is added in an amount of 0.1 to 1.0 parts by weight based on 100 parts by weight of the lubricating oil composition. Preferably, the pour point depressant is polymethacrylate. Specifically, the pour point depressant used in the present invention is a commercially available product on the market, including but not limited to: VISCOPLEX 1-180, VISCOPLEX 1-360, etc. from Evonik.

[0057] In one embodiment of the present invention, based on 100 parts by weight of the lubricating oil composition, the amount of the antioxidant added is 0.1 to 3.0 parts by weight, preferably 0.1 to 2.0 parts by weight. Preferably, the antioxidant is a phenolic antioxidant, an amine antioxidant, or a mixture of the two. Among them, phenolic antioxidants include but are not limited to 2,6-di-tert-butyl-p-cresol (BHT), 2-naphthol, etc. Amine antioxidants include but are not limited to dialkyl diphenylamine, phenyl-α-naphthylamine, etc. Specifically, the antioxidant used in the present invention adopts relevant products commercially available on the market, including but not limited to: phenolic antioxidants such as T501 of Rhein Chemie and RF1135 of Ruifeng New Materials; amine antioxidants such as Irganox L55 of BASF, T545 of Beijing Xingpu Fine Chemicals, and RF5067 of Ruifeng New Materials.

[0058] In one embodiment of the present invention, the amount of the rust inhibitor added is 0.1 to 5.0 parts by weight, preferably 0.1 to 2.0 parts by weight, based on 100 parts by weight of the lubricating oil composition. Preferably, the rust inhibitor is selected from one or more of alkenyl succinates, organic phosphate amine salts, benzotriazole derivatives and thiadiazole derivatives. Specifically, the rust inhibitor used in the present invention adopts commercially available related products on the market, including but not limited to alkenyl succinic acid products such as Wuxi Nanfang's T746; phosphate ester ammonium salts such as Vanlube 9123 of Vanderbilt.

[0059] In one embodiment of the present invention, based on 100 parts by weight of the lubricating oil composition, the amount of the antifoaming agent added is 0.01 to 0.1 parts by weight, preferably 0.01 to 0.06 parts by weight. Preferably, the antifoaming agent is selected from at least one of dimethyl silicone oil / oil ester antifoaming agent and polyacrylate antifoaming agent or a combination thereof. Specifically, the antifoaming agent used in the present invention adopts relevant commercially available products on the market, including but not limited to: methyl silicone oil / oil ester antifoaming agents such as T901 and T903 of Jinzhou Xinxing Petroleum Additives Company; 1# composite antifoaming agent of Jinzhou Donggong Petrochemical Company, etc.

[0060] In one embodiment of the present invention, the lubricating oil composition as a special wet electric drive oil can not only be used for the three-in-one electric axle of pure electric heavy-load commercial vehicles, but also can be used for the lubrication and cooling of non-integrated motors and single-stage / multi-stage reducers, and has great market value and potential.

[0061] The following further examples are given to illustrate the present invention in detail. It should also be understood that the following examples are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made by those skilled in the art based on the above content of the present invention belong to the scope of protection of the present invention. The specific process parameters and the like in the following examples are also only examples within a suitable range, that is, those skilled in the art can make a selection within a suitable range through the description herein, and are not limited to the specific values ​​​​exemplified below.

[0062] Examples 1-5

[0063] The viscosity grade of the lubricating oil composition provided in Examples 1-5 is SAE 75W-80. The composition of the lubricating oil composition is shown in Table 1. The preparation methods of Examples 1-5 all include the following: heating the base oil to 60±1°C, then sequentially adding an extreme pressure anti-wear agent, a friction modifier, an antioxidant, a pour point depressant and a rust inhibitor, and stirring for 1 hour until uniform; then sequentially adding an optional viscosity index improver and an anti-foaming agent, and stirring at the temperature for 1 hour.

[0064] Comparative Example 1

[0065] Commercially available oil A has a viscosity grade of SAE 75W-80 and its performance meets the GL-4 specification.

[0066] Comparative Example 2

[0067] Commercially available oil B has a viscosity grade of SAE 80W-90 and its performance meets GL-5 specifications.

[0068] Table 1 Composition of the lubricating oil composition in Examples 1-5 (unit: parts by weight)

[0069]

[0070]

[0071] Table 2 Performance indicators and experimental methods of lubricating oil composition:

[0072] Test Project unit Test methods Kinematic viscosity at 100℃ <![CDATA[mm 2 / s]]> GB / T 265 Kinematic viscosity at 40℃ <![CDATA[mm 2 / s]]> GB / T 265 Viscosity Index VI GB / T 1995 Pour Point ℃ GB / T 3535 -40℃ Brookfield viscosity mPa·s GB / T 11145 Copper corrosion (150℃, 168h) class ASTM D130 FZG(A10 / 16.6R / 90) class CEC L-84-02 Breakdown voltage 30℃ kV IEC 60156 Specific heat capacity 30℃ J / (g·K) ASTM D7896 Specific heat capacity 80℃ J / (g·K) ASTM D7896 Heat transfer coefficient 30℃ mW / (m·K) ASTM D7896 Heat transfer coefficient 80℃ mW / (m·K) ASTM D7896

[0073] Table 3 Performance index data of the lubricating oil composition in Examples 1-5 and Comparative Examples 1-2:

[0074] Test Project unit E1 E2 E3 E4 E5 C1 C2 Kinematic viscosity at 100℃ <![CDATA[mm 2 / s]]> 9.3 9.7 9.4 9.5 5.5 10.72 15.64 Kinematic viscosity at 40℃ <![CDATA[mm 2 / s]]> 48.5 68.2 61.9 52.1 25.75 76.11 156 Viscosity Index VI 184 154 144 169 160 128 102 Pour Point ℃ -54 -51 -42 -45 -45 -33 -30 -40℃ Brookfield viscosity mPa·s 43400 55000 108800 93000 85600 / / Copper corrosion (150℃, 168h) class 1a 1b 1b 1b 1a 4c 4c FZG(A10 / 16.6R / 90) class 11 11 11 11 10 11 12 Breakdown voltage 30℃ kV 57 50 52 57 53 42 40 Specific heat capacity 30℃ J / (g·K) 2.20 2.20 2.15 2.22 2.16 2.08 1.91 Specific heat capacity 80℃ J / (g·K) 2.42 2.38 2.37 2.41 2.34 2.30 2.12 Heat transfer coefficient 30℃ mW / (m·K) 158.1 157.9 157.4 159.8 154.4 150.9 146.4 Heat transfer coefficient 80℃ mW / (m·K) 148.9 147.6 147.2 149.2 144.9 142.1 139.3

[0075] It can be seen from the data in Table 1 and Table 3 that in Examples 1-5, the base oil, viscosity index improver and various additives are reasonably compounded, so that the formulated lubricating oil composition (i.e., SAE 75W-80, a special oil for wet electric drive of heavy-duty commercial vehicles) has excellent low-temperature fluidity, the pour point is below -40°C, and the low-temperature Brookfield viscosity at -40°C is below 110000 mPa·s; it has excellent copper corrosion protection ability, and the copper sheet rating after ASTM D130 test is not less than grade 1b; it has a gear bearing load capacity comparable to that of traditional gear oils, providing reliable lubrication for the gear system; and it has good heat capacity and heat conduction efficiency performance.

[0076] In summary, the lubricating oil composition for wet electric drive of heavy-duty commercial vehicles of the present invention has excellent low-temperature fluidity and pumpability, outstanding electrical and thermal properties, good rust and corrosion resistance, excellent insulation material compatibility, outstanding extreme pressure and anti-wear properties, and stable thermal oxidation stability. As a special oil for wet electric drive, the lubricating oil composition of the present invention can be used not only for the three-in-one electric bridge of pure electric heavy-duty commercial vehicles, but also for the lubrication and cooling of non-integrated motors and single-stage / multi-stage reducers, and has great market value and potential.

[0077] It should be noted that all technical features described in the present invention can be freely combined or combined in any way unless there is a contradiction between them. Various modifications and changes can be made to the present invention without departing from the scope of the present invention, which will be obvious to those skilled in the art. For example, a feature shown or described as part of one embodiment can be used together with another embodiment to produce another embodiment. Therefore, the present invention is intended to cover these modifications that fall within the scope of the appended claims and their equivalents.

Claims

1. A lubricating oil composition, characterized in that: Based on 100 parts by weight of the lubricating oil composition, the lubricating oil composition comprises the following components: a) 60 to 90 parts by weight of base oil; b) 0 to 20 parts by weight of a viscosity index improver; c) 0.5 to 6.0 parts by weight of an extreme pressure anti-wear agent; d) 0.2 to 5.0 parts by weight of a friction modifier; e) 0.1 to 1.0 parts by weight of a pour point depressant; f) 0.1 to 3.0 parts by weight of an antioxidant; g) 0.1 to 5.0 parts by weight of a rust inhibitor; h) 0.01 to 1 parts by weight of an antifoaming agent; The lubricating oil composition has a breakdown voltage of at least 50 kV at 30°C.

2. The lubricating oil composition according to claim 1, characterized in that Based on 100 parts by weight of the lubricating oil composition, the lubricating oil composition comprises the following components: a) 82 to 90 parts by weight of base oil; b) 0 to 8 parts by weight of a viscosity index improver; c) 2.5 to 5.0 parts by weight of an extreme pressure antiwear agent; d) 2.0 to 5.0 parts by weight of a friction modifier; e) 0.1 to 1.0 parts by weight of a pour point depressant; f) 0.1 to 2.0 parts by weight of an antioxidant; g) 0.1 to 2.0 parts by weight of a rust inhibitor; h) 0.01 to 0.06 parts by weight of an antifoaming agent.

3. The lubricating oil composition according to claim 1 or 2, characterized in that: The base oil is mineral oil and / or synthetic base oil; Preferably, the mineral oil is selected from Class III mineral oil, and the synthetic base oil is selected from at least one of synthetic oil produced by Fischer-Tropsch reaction, poly-α-olefin PAO synthetic oil, and hyperbranched polyethylene synthetic oil, or a combination thereof; Preferably, the kinematic viscosity of the synthetic oil produced by the Fischer-Tropsch reaction at 100°C is 2.0 to 100.0 mm 2 / s, the kinematic viscosity of the poly-alpha-olefin PAO synthetic oil at 100°C is 4.0-150.0 mm 2 / s, the kinematic viscosity of the hyperbranched polyethylene synthetic oil at 100°C is 2.0 to 100.0 mm 2 / s.

4. The lubricating oil composition according to claim 1 or 2, characterized in that: The viscosity index improver is selected from at least one of polymethacrylate copolymer, ethylene-propylene copolymer, hydrogenated styrene diene copolymer or a combination thereof; preferably, the viscosity index improver is polymethacrylate copolymer.

5. The lubricating oil composition according to claim 1 or 2, characterized in that: The extreme pressure anti-wear agent is selected from at least one of organic phosphates, acidic phosphate ammonium salts, phosphoric acid amides and alkyl phosphites or a combination thereof, and is preferably acidic phosphate ammonium salts.

6. The lubricating oil composition according to claim 1 or 2, characterized in that: The friction modifier is selected from at least one of ethoxylated amines, fatty acid glycerides, and benzotriazole fatty amine salts, or a combination thereof.

7. The lubricating oil composition according to claim 1 or 2, characterized in that: The pour point depressant is selected from polymethacrylate.

8. The lubricating oil composition according to claim 1 or 2, characterized in that: The antioxidant is selected from phenolic antioxidants and / or amine antioxidants.

9. The lubricating oil composition according to claim 1 or 2, characterized in that: The rust inhibitor is selected from at least one of alkenyl succinate, organic phosphate amine salt, benzotriazole derivative and thiadiazole derivative or a combination thereof.

10. The lubricating oil composition according to claim 1 or 2, characterized in that: The antifoaming agent is selected from at least one of dimethyl silicone oil / oil ester antifoaming agent and polyacrylate antifoaming agent or a combination thereof.

11. The lubricating oil composition according to claim 1 or 2, characterized in that: The lubricating oil composition has one or more of the following characteristics: The kinematic viscosity of the lubricating oil composition at 100° C. is 5.0 to 11.0 mm 2 / s, pour point not higher than -40℃; The Brookfield viscosity of the lubricating oil composition at -40°C is ≤110000 mPa·s, preferably ≤90000 mPa·s; The lubricating oil composition has a corrosion grade of not less than 1b in copper sheet corrosion; The lubricating oil composition has a specific heat capacity of 2.10 to 2.30 J / (g·K) at 30°C; The lubricating oil composition has a specific heat capacity of 2.34 to 2.50 J / (g·K) at 80°C; The heat transfer coefficient of the lubricating oil composition at 30° C. is 154 to 160 mW / (m·K); The heat transfer coefficient of the lubricating oil composition at 80° C. is 144 to 150 mW / (m·K).

12. Use of the lubricating oil composition according to any one of claims 1 to 11 in the field of mechatronic transmission assemblies of new energy commercial vehicles.

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