Zinc-free type railway locomotive diesel engine lubricating oil composition and preparation method thereof

Abstract

The invention discloses a zinc-free railway locomotive diesel engine lubricating oil composition which comprises the following components in percentage by mass: 5.0-8.0% of a high-temperature detergent, 3.0-6.0% of an ashless dispersant, 2.0-4.0% of a multifunctional additive, 0.5-1.5% of an ashless antioxidant preservative, 0.5-1.5% of a composite antioxidant, 0.2-0.5% of a pour point depressant, 0.0015-0.0050% of an anti-foaming agent and the balance of catalytic hydrogenation base oil, and the sum of the mass percentages of the components is 100%. The invention also discloses a preparation method of the lubricating oil composition, which specifically comprises the following steps: mixing the components, and stirring at 55-65 DEG C until the components are uniformly mixed. Through the multifunctional additive, the ash-free antioxidant preservative and the like, multiple functions of oxidation resistance, wear resistance, corrosion resistance and the like of ZDDP in lubricating oil are replaced, and the same or better performance as zinc-containing locomotive diesel engine oil can be achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of lubricating oil additives, and in particular relates to a zinc-free railway locomotive diesel engine lubricating oil composition, and also relates to a preparation method of the railway locomotive diesel engine lubricating oil composition. Background Art

[0002] Compared with ordinary diesel engines, locomotive diesel engines have the characteristics of high horsepower, high peak torque, low speed, and large displacement. Another significant difference is that some locomotive diesel engines use silver-plated bearing parts in their superchargers, crank pins and other parts. Since zinc salt additives are corrosive to silver, such locomotive diesel engines need to use zinc-free lubricants. The zinc in lubricants mainly comes from anti-wear and corrosion inhibitors (zinc dialkyl dithiophosphate, ZDDP). This type of additive is a multifunctional additive commonly used in engine lubricants because it has multiple functions such as anti-oxidation, anti-corrosion, and anti-wear.

[0003] A Chinese patent (application number: 201910958561.5, publication number: CN112646646A) discloses a railway locomotive oil composition, comprising the following components: 4 to 10 parts of a metal detergent, the metal detergent being composed of the following components: an ultra-high base phenol salt having an alkalinity of 290 to 310 mgKOH / g, an ultra-high base sulfonate having an alkalinity of 380 to 420 mgKOH / g, and a low base sulfonate having an alkalinity of 25 to 35 mgKOH / g; 2 to 8 parts of a dispersant; 0.5 to 2 parts of an anti-wear preservative; 0.5 to 3 parts of a composite antioxidant; and 70 to 90 parts of a base oil. A Chinese patent (application number: 201710431332.9, publication number: CN107338092A) discloses an internal combustion locomotive oil composition, comprising the following components: a) 3 to 10 parts of a metal detergent; the metal detergent is composed of 0.5 to 3.5 parts of a sulfonate, 0.5 to 3.5 parts of a sulfurized alkylphenol salt and 2 to 9 parts of a salicylate; b) 3 to 7 parts of a low molecular weight polyisobutylene succinimide ashless dispersant, the molecular weight of which ranges from 3000 to 3200; c) 0.5 to 3 parts of a phosphorus-containing anti-wear preservative; d) 0.5 to 3 parts of a composite antioxidant; e) 80 to 95 parts of a base oil. Chinese patent (application number: 201610833590.5, publication number: CN106635281A) discloses a diesel locomotive oil composition, including the following components: a) 3 to 10 parts of metal detergent; the metal detergent is composed of 0.5 to 3.5 parts of sulfonate, 0.5 to 3.5 parts of sulfurized alkylphenol and 2 to 9 parts of salicylate; b) 3 to 7 parts of nitrogen-containing ashless dispersant; c) 0.5 to 3 parts of phosphorus-containing anti-wear and corrosion inhibitor; d) 0.5 to 3 parts of composite antioxidant; the composite antioxidant is composed of 0.1 to 0.5 parts of amine antioxidant, 0.1 to 0.5 parts of phenolic antioxidant and 0.2 to 1 parts of zinc thiocarbamate; e) 80 to 95 parts of base oil. The railway locomotive diesel engine lubricating oil composition mentioned in the above technology contains a certain proportion of anti-wear and corrosion inhibitor ZDDP, which is not suitable for railway diesel locomotives containing silver bearings. There is no report on zinc-free railway locomotive diesel engine lubricating oil composition. Summary of the invention

[0004] The object of the present invention is to provide a zinc-free railway locomotive diesel engine lubricating oil composition, which has good antioxidant and anti-wear properties and can effectively extend the oil change cycle.

[0005] Another object of the present invention is to provide a method for preparing a zinc-free railway locomotive diesel engine lubricating oil composition.

[0006] The technical scheme adopted by the present invention is that the zinc-free railway locomotive diesel engine lubricating oil composition comprises the following components by mass percentage: 5.0% to 8.0% of high-temperature detergent, 3.0% to 6.0% of ashless dispersant, 2.0% to 4.0% of multifunctional additive, 0.5% to 1.5% of ashless antioxidant preservative, 0.5% to 1.5% of composite antioxidant, 0.2% to 0.5% of pour point depressant, 0.0015% to 0.0050% of methyl silicone oil antifoaming agent, and the balance is catalytic hydrogenation base oil, and the sum of the mass percentages of the above components is 100%.

[0007] The present invention is also characterized in that:

[0008] The high-temperature detergent comprises the following components by mass percentage: 55% to 65% by mass of sulfurized alkylphenol salt, and the remainder is alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

[0009] Sulfurized alkyl phenol salts include the following components by mass percentage: medium-base value sulfurized alkyl phenol calcium accounts for 20% to 80% by mass, and the remainder is high-base value sulfurized alkyl phenol calcium, and the sum of the mass percentages of the above components is 100%;

[0010] The alkyl salicylate comprises the following components by mass percentage: 30% to 70% by mass of medium-base calcium alkyl salicylate, and the remainder is high-base calcium alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

[0011] The ashless dispersant is polyisobutylene succinimide; the polyisobutylene succinimide is any one or two of single-hanging polyisobutylene succinimide and double-hanging polyisobutylene succinimide; the ashless antioxidant preservative is dialkyl dithiocarbamate.

[0012] The multifunctional additive is 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-methyl-N-ylcarbamate.

[0013] The composite antioxidant comprises the following components by mass percentage: 60% to 75% of amine antioxidant and the remainder of phenol antioxidant, and the sum of the mass percentages of the above components is 100%.

[0014] The amine antioxidant is any one or two of butyloctyldiphenylamine and dioctyldiphenylamine; the phenol antioxidant is any one or two of 2,6-di-tert-butyl-p-cresol and high molecular weight phenol ester compounds.

[0015] The catalytic hydrogenation base oil comprises the following components by mass percentage: the middle component hydrogenation base oil accounts for 70% to 90% by mass, and the remainder is the heavy component hydrogenation base oil. The sum of the mass percentages of the above components is 100%.

[0016] Another technical solution adopted by the present invention is a method for preparing a zinc-free railway locomotive diesel engine lubricating oil composition, which specifically comprises: mixing a high-temperature detergent, an ashless dispersant, a multifunctional additive, an ashless antioxidant preservative, a composite antioxidant, a pour point depressant, a methyl silicone oil antifoaming agent and a catalytic hydrogenation base oil, and stirring at 55°C-65°C until the mixture is uniform, thereby obtaining a diesel engine lubricating oil composition.

[0017] The beneficial effects of the present invention are as follows: by optimizing the composition of the high-temperature detergent, introducing 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-methyl-N-yl carbamate as an antioxidant and anti-wear multifunctional additive, introducing an ashless antioxidant preservative, etc., the antioxidant, anti-wear, anti-corrosion and other functions of ZDDP in the lubricating oil are replaced, and a zinc-free railway locomotive diesel engine lubricating oil composition is formed, which can achieve the same or better performance as that of zinc-containing railway locomotive diesel engine oil. DETAILED DESCRIPTION

[0018] The present invention is described in detail below in conjunction with specific implementation modes.

[0019] The zinc-free railway locomotive diesel engine lubricating oil composition of the present invention comprises the following components by mass percentage: 5.0%-8.0% of high-temperature detergent, 3.0%-6.0% of ashless dispersant, 2.0%-4.0% of multifunctional additive, 0.5%-1.5% of ashless antioxidant preservative, 0.5%-1.5% of composite antioxidant, 0.2%-0.5% of pour point depressant, 0.0015%-0.0050% of methyl silicone oil antifoaming agent, and the balance is catalytic hydrogenation base oil, and the sum of the mass percentages of the above components is 100%.

[0020] The high-temperature detergent includes the following components by mass percentage: 55% to 65% by mass of sulfurized alkylphenol salt, and the remainder is alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

[0021] The sulfurized alkylphenol salt in the high temperature detergent component is composed of sulfurized alkylphenol calcium with medium base value and sulfurized alkylphenol calcium with high base value;

[0022] The sulfide alkyl phenol salt comprises the following components by mass percentage: medium alkaline value sulfide alkyl phenol calcium accounts for 20% to 80% by mass, and the remainder is high alkaline value sulfide alkyl phenol calcium, and the sum of the mass percentages of the above components is 100%.

[0023] Among them, the total base value of medium-base sulfide alkyl phenol calcium is 130-200 mgKOH / g, and the total base value of high-base sulfide alkyl phenol calcium is not less than 250 mgKOH / g;

[0024] The alkyl salicylate in the high temperature detergent component is composed of medium base calcium alkyl salicylate and high base calcium alkyl salicylate;

[0025] The alkyl salicylate comprises the following components by mass percentage: 30% to 70% by mass of medium-base calcium alkyl salicylate, and the remainder is high-base calcium alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

[0026] The total base value of medium-base alkyl calcium salicylate is 160-250 mgKOH / g, and the total base value of high-base alkyl calcium salicylate is not less than 290 mgKOH / g;

[0027] The high-temperature detergent in the present invention does not contain sulfonates, but only contains sulfurized alkylphenols and alkyl salicylates with auxiliary antioxidant properties, and the sulfurized alkylphenols with better antioxidant properties account for a higher proportion, which can significantly improve the antioxidant properties of the composition and partially replace the antioxidant effect of the ZDDP additive.

[0028] The ashless dispersant is polyisobutylene succinimide; the polyisobutylene succinimide is any one or two of single-hanging polyisobutylene succinimide and double-hanging polyisobutylene succinimide;

[0029] The multifunctional additive is 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-methyl-N-ylcarbamate, and its structure is as follows:

[0030]

[0031] The carbamate and benzofuran groups contained in the structure of the multifunctional additive can form a conjugated structure, which can timely capture the free radical intermediates generated during the oxidation process of the engine oil, block the oxidation reaction chain, and have a significant anti-oxidation effect; in addition, the multifunctional additive has good metal adsorption capacity, and can form a firm adsorption film on the surface of the engine piston ring cylinder sleeve friction pair, crankshaft bearing friction pair, etc., to reduce friction and wear. The multifunctional additive can greatly improve the antioxidant and anti-wear properties of the composition of the present invention, and can effectively extend the oil change cycle.

[0032] The ashless antioxidant preservative is a dialkyl dithiocarbamate.

[0033] The composite antioxidant comprises the following components by mass percentage: 60% to 75% of amine antioxidant and the remainder of phenol antioxidant, and the sum of the mass percentages of the above components is 100%.

[0034] Too high or too low a ratio of the amine antioxidant will affect the antioxidant properties of the composition of the present invention.

[0035] The amine antioxidant is any one or two of butyl octyl diphenylamine and dioctyl diphenylamine;

[0036] The phenolic antioxidant is any one or two of 2,6-di-tert-butyl-p-cresol and high molecular weight phenol ester compounds;

[0037] The catalytic hydrogenation base oil comprises the following components by mass percentage: the middle component hydrogenation base oil accounts for 70% to 90% by mass, and the remainder is the heavy component hydrogenation base oil. The sum of the mass percentages of the above components is 100%.

[0038] The kinematic viscosity of the medium component hydrogenated base oil at 100°C is 9.0-11.0 mm 2 / s, viscosity index is not less than 95; the kinematic viscosity of the heavy component hydrogenated base oil at 100°C is 28.0~34.0mm 2 / s, viscosity index is 80~90.

[0039] The preparation method of the zinc-free railway locomotive diesel engine lubricating oil composition of the present invention specifically comprises: mixing a high-temperature detergent, an ashless dispersant, a multifunctional additive, an ashless antioxidant preservative, a composite antioxidant, a pour point depressant, a methyl silicone oil antifoaming agent and a catalytic hydrogenation base oil, and stirring at 55° C.-65° C. until the mixture is uniformly mixed to obtain the diesel engine lubricating oil composition.

[0040] Example 1

[0041] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 1:

[0042] Table 1 Composition and ratio of diesel engine lubricating composition in Example 1

[0043]

[0044]

[0045] Among them, the base oil composition is shown in Table 2:

[0046] Table 2 Example 1 Base oil composition and ratio

[0047] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0048] Example 2

[0049] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 3:

[0050] Table 3 Composition and proportion of diesel engine lubricating oil composition in Example 2

[0051]

[0052]

[0053] Among them, the base oil composition is shown in Table 4:

[0054] Table 4 Example 2 Base oil composition and ratio

[0055] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0056] Example 3

[0057] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 5:

[0058] Table 5 Composition and proportion of diesel engine lubricating oil composition in Example 3

[0059]

[0060]

[0061] Among them, the base oil composition is shown in Table 6:

[0062] Table 6 Example 3 base oil composition and ratio

[0063] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0064] Example 4

[0065] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 7:

[0066] Table 7 Composition and ratio of diesel engine lubricating oil composition in Example 4

[0067]

[0068]

[0069] Among them, the base oil composition is shown in Table 8:

[0070] Table 8 Example 4 Base oil composition and ratio

[0071] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0072] Example 5

[0073] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 9:

[0074] Table 9 Composition and proportion of diesel engine lubricating oil composition in Example 5

[0075]

[0076]

[0077] Among them, the base oil composition is shown in Table 10:

[0078] Table 10 Example 5 Base oil composition and ratio

[0079] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0080] Example 6

[0081] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 11:

[0082] Table 11 Composition and proportion of diesel engine lubricating oil composition in Example 6

[0083] Components content(%) Medium base value sulphurized calcium alkyl phenol 2.0 High base value sulphurized calcium alkyl phenol 2.2 Medium base calcium alkyl salicylate 1.4 Overbased calcium alkyl salicylate 1.4 Bisuccinimide dispersant 4.0 Multifunctional Additives 3.0 Ashless antioxidant preservative 1.5 Bis(octyl)diphenylamine 0.8 Polymer phenol ester 0.4 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0084] Among them, the base oil composition is shown in Table 12:

[0085] Table 12 Example 6 Base oil composition and ratio

[0086] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0087] Example 7

[0088] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 13:

[0089] Table 13 Composition and proportion of diesel engine lubricating oil composition of Example 7

[0090] Components content(%) Medium base value sulphurized calcium alkyl phenol 2.0 High base value sulphurized calcium alkyl phenol 1.6 Medium base calcium alkyl salicylate 1.2 Overbased calcium alkyl salicylate 1.2 Monosuccinimide dispersant 2.0 Bisuccinimide dispersant 2.0 Multifunctional Additives 3.0 Ashless antioxidant preservative 1.0 Bis-octyl diphenylamine 0.7 2,6-Di-tert-butyl-p-cresol 0.3 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0091] Among them, the base oil composition is shown in Table 14:

[0092] Table 14 Example 7 Base oil composition and ratio

[0093] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0094] Example 8

[0095] The composition of the diesel engine lubricating oil composition of this embodiment is shown in Table 15:

[0096] Table 15 Composition and proportion of diesel engine lubricating oil composition in Example 8

[0097] Components content(%) Medium base value sulphurized calcium alkyl phenol 2.0 High base value sulphurized calcium alkyl phenol 1.6 Medium base calcium alkyl salicylate 1.2 Overbased calcium alkyl salicylate 1.2 Monosuccinimide dispersant 2.0 Bisuccinimide dispersant 2.0 Multifunctional Additives 4.0 Ashless antioxidant preservative 1.0 Butyl octyl diphenylamine 0.7 2,6-Di-tert-butyl-p-cresol 0.3 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0098] Among them, the base oil composition is shown in Table 16:

[0099] Table 16 Example 8 Base oil composition and ratio

[0100] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0101] Comparative Example 1

[0102] The composition of the diesel engine lubricating oil composition of this comparative example is shown in Table 17:

[0103] Table 17 Comparative Example 1 Composition and ratio of diesel engine lubricating oil composition

[0104] Components content(%) Medium base value sulphurized calcium alkyl phenol 2.5 High base value sulphurized calcium alkyl phenol 2.5 Medium base calcium alkyl salicylate 0.5 Overbased calcium alkyl salicylate 0.5 Bisuccinimide dispersant 4.0 Zinc butyloctyl dithiophosphate (ZDDP) 2.0 Ashless antioxidant preservative 1.0 Butyl octyl diphenylamine 0.7 2,6-Di-tert-butyl-p-cresol 0.3 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0105] Among them, the base oil composition is shown in Table 18:

[0106] Table 18 Comparative Example 1 Base Oil Composition and Ratio

[0107] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0108] Comparative Example 2

[0109] The composition of the diesel engine lubricating oil composition of this comparative example is shown in Table 19:

[0110] Table 19 Composition and ratio of diesel engine lubricating oil composition of comparative example 2

[0111] Components content(%) Medium base value sulphurized calcium alkyl phenol 2.0 High base value sulphurized calcium alkyl phenol 1.6 Medium base calcium alkyl salicylate 1.2 Overbased calcium alkyl salicylate 1.2 Bisuccinimide dispersant 4.0 Zinc butyloctyl dithiophosphate (ZDDP) 3.0 Ashless antioxidant preservative 1.0 Butyl octyl diphenylamine 0.7 2,6-Di-tert-butyl-p-cresol 0.3 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0112] Among them, the base oil composition is shown in Table 20:

[0113] Table 20 Comparative Example 2 Base Oil Composition and Ratio

[0114] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0115] Comparative Example 3

[0116] The composition of the diesel engine lubricating oil composition of this comparative example is shown in Table 21:

[0117] Table 21 Composition and proportion of diesel engine lubricating oil composition of comparative example 3

[0118] Components content(%) Medium base value sulphurized calcium alkyl phenol 0.5 High base value sulphurized calcium alkyl phenol 0.5 Medium base calcium alkyl salicylate 2.5 Overbased calcium alkyl salicylate 2.5 Bisuccinimide dispersant 4.0 Multifunctional Additives 2.0 Ashless antioxidant preservative 1.0 Butyl octyl diphenylamine 0.7 2,6-Di-tert-butyl-p-cresol 0.3 Pour Point Depressant 0.3 Methyl silicone oil antifoaming agent 0.002 Base oil margin

[0119] Among them, the base oil composition is shown in Table 22:

[0120] Table 22 Comparative Example 3 Base Oil Composition and Ratio

[0121] Components content(%) Medium component hydrogenated base oil 80 Heavy component hydrogenated base oil 20

[0122] The anti-oxidation performance, anti-wear performance and high-temperature cleaning performance of the railway locomotive diesel engine lubricating oil composition blended from the above embodiments and comparative examples were evaluated. The anti-oxidation performance was evaluated by PDSC oxidation induction period and simulated oxidation test, wherein the PDSC test temperature was 200°C and the oxygen pressure was 2.45mPa; the simulated oxidation test temperature was 180°C, copper sheets and steel sheets were added for catalysis, the test period was 96h, and the 100°C kinematic viscosity change rate of the oxidized oil was measured to determine the oxidation degradation of the oil. The anti-wear performance was evaluated by the friction coefficient of the SRV test machine and the wear spot diameter of the four-ball test machine. The high-temperature cleaning performance was evaluated by the coking weight of the coking plate test. The evaluation results are shown in Table 23.

[0123] Table 23 Simulation evaluation test results

[0124]

[0125]

[0126] The test results show that, in Example 1, Example 2, and Example 3, as the amount of multifunctional additive increases, the PDSC oxidation induction period shows a significant increasing trend, and the viscosity growth rate in the simulated oxidation test shows a decreasing trend, showing a significant improvement in antioxidant performance; the SRV friction coefficient and the four-ball wear spot diameter both show a decreasing trend, and the anti-wear performance is gradually enhanced. Compared with Comparative Example 1 and Comparative Example 2 in which zinc dialkyl dithiophosphate ZDDP is added, the antioxidant and anti-wear performance are better, indicating that the multifunctional additive has good antioxidant and anti-wear performance.

[0127] The proportion of the multifunctional additive in Example 4, Example 5, and Example 6 is relatively low, but by increasing the proportion of the high-temperature detergent and increasing the amount of the ashless antioxidant preservative, a significant improvement in the antioxidant performance is reflected, and the antioxidant performance level of the embodiments with a higher amount of multifunctional additives can be achieved. The performance is equivalent to or better than that of Comparative Example 1 and Comparative Example 2 in which zinc dialkyl dithiophosphate ZDDP is added, indicating the beneficial effects of the optimized high-temperature detergent component and ashless antioxidant preservative component in the present invention.

[0128] In Comparative Example 1, the proportion of sulfurized alkylphenol salt in the high-temperature detergent component is 83.3%. Although the antioxidant performance is good, it has an adverse effect on the high-temperature detergent performance. From the coking weight of the coke plate, it can be found that the coking weight of this scheme is significantly larger; in Comparative Example 3, the proportion of sulfurized alkylphenol salt in the high-temperature detergent component is 16.7%. The higher salicylate significantly improves the high-temperature detergent performance. The coking weight of the coke plate is very low, only 25.1 mg, but the antioxidant performance is poor, the PDSC oxidation induction period is the shortest, and the viscosity growth rate of the simulated oxidation test is the largest. In Examples 1-8, the proportion of sulfurized alkylphenol salt in the high-temperature detergent component is 55%-65%. Within this range, the oil products show a good balance of antioxidant performance and high-temperature detergent performance, indicating the beneficial effect of the present invention on the optimization of the high-temperature detergent component.

[0129] The analysis of the results of the examples fully demonstrates that the present invention replaces the antioxidant, anti-wear, anti-corrosion and other functions of ZDDP in lubricating oil through a combination of various technologies such as optimization of the high-temperature detergent scheme, introduction of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-methyl-N-ylcarbamate as an antioxidant and anti-wear multifunctional additive, and introduction of an ashless antioxidant preservative, thereby forming a zinc-free railway locomotive diesel engine lubricating oil composition that can achieve the same or better performance as zinc-containing railway locomotive diesel engine oil.

Claims

1. A zinc-free railway locomotive diesel engine lubricating oil composition, characterized in that: The invention comprises the following components by mass percentage: 5.0% to 8.0% of high temperature detergent, 3.0% to 6.0% of ashless dispersant, 2.0% to 4.0% of multifunctional additive, 0.5% to 1.5% of ashless antioxidant preservative, 0.5% to 1.5% of composite antioxidant, 0.2% to 0.5% of pour point depressant, 0.0015% to 0.0050% of methyl silicone oil antifoaming agent, and the remainder is catalytic hydrogenation base oil. The sum of the mass percentages of the above components is 100%.

2. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 1, characterized in that: The high-temperature detergent comprises the following components by mass percentage: 55% to 65% by mass of sulfurized alkylphenol salt, and the remainder is alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

3. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 2, characterized in that: The sulphurized alkyl phenate comprises the following components by mass percentage: 20% to 80% by mass of sulphurized alkyl phenate calcium with a medium base value, and the remainder is sulphurized alkyl phenate calcium with a high base value, and the sum of the mass percentages of the above components is 100%; The alkyl salicylate comprises the following components by mass percentage: 30% to 70% by mass of medium-base calcium alkyl salicylate, and the remainder is high-base calcium alkyl salicylate, and the sum of the mass percentages of the above components is 100%.

4. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 1, characterized in that: The ashless dispersant is polyisobutylene succinimide; the polyisobutylene succinimide is any one or two of single-hanging polyisobutylene succinimide and double-hanging polyisobutylene succinimide; the ashless antioxidant preservative is dialkyl dithiocarbamate.

5. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 1, characterized in that: The multifunctional additive is 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-methyl-N-yl carbamate, and its structure is as follows:

6. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 1, characterized in that: The composite antioxidant comprises the following components by mass percentage: 60% to 75% of amine antioxidant and the remainder of phenolic antioxidant, and the sum of the mass percentages of the above components is 100%.

7. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 6, characterized in that: The amine antioxidant is any one or two of butyloctyldiphenylamine and dioctyldiphenylamine; the phenol antioxidant is any one or two of 2,6-di-tert-butyl-p-cresol and high molecular weight phenol ester compounds.

8. The zinc-free railway locomotive diesel engine lubricating oil composition according to claim 1, characterized in that: The catalytic hydrogenation base oil comprises the following components by mass percentage: a medium component hydrogenation base oil accounts for 70% to 90% by mass, and the remainder is a heavy component hydrogenation base oil, and the sum of the mass percentages of the above components is 100%.

9. The method for preparing the zinc-free railway locomotive diesel engine lubricating oil composition according to any one of claims 1 to 8, characterized in that: Specifically, a high-temperature detergent, an ashless dispersant, a multifunctional additive, an ashless antioxidant preservative, a composite antioxidant, a pour point depressant, a methyl silicone oil antifoaming agent and a catalytic hydrogenation base oil are mixed, and stirred at 55°C-65°C until the mixture is uniform to obtain a diesel engine lubricating oil composition.

Images