Nano-copper-containing wind power gear oil with micro pitting corrosion resistance as well as preparation method and application of nano-copper-containing wind power gear oil

Abstract

The invention discloses wind power gear oil with micro pitting corrosion resistance and containing nano copper as well as a preparation method and application of the wind power gear oil. The wind power gear oil comprises synthetic base oil and a nano-copper solution, wherein the addition amount of the nano-copper solution accounts for 0.5%-2% of the wind power gear oil; wherein the nano-copper solution is obtained by dissolving modified nano-copper in an ether solvent, the mass percentage of Cu in the nano-copper solution is greater than or equal to 12%, and the kinematic viscosity of the synthetic base oil at 40 DEG C is not less than 300 mm < 2 >. S <-1 >. By controlling the performance parameters of the base oil, the nano-copper particles and the base oil have a synergistic effect, and appearance and expansion of surface micro-pitting corrosion can be reduced.

Description

Technical Field

[0001] This invention relates to the field of lubrication materials technology, and in particular to a wind turbine gear oil containing nano-copper with anti-micropitting properties, its preparation method and application. Background Technology

[0002] Micropitting is a type of surface roughness damage caused by fatigue spalling of micro-protrusions on a metal surface under long-term cyclic frictional contact. It commonly occurs in basic components such as gears and bearings. Specifically, micropitting is a microscale fatigue damage phenomenon occurring on the surface of rolling / sliding contact mechanical parts (such as gears and bearings). In the industrial field, it is also known as "gray spots." It manifests as densely distributed tiny pits on the contact surface, typically with a depth between 2 and 13 micrometers, rarely exceeding 25 micrometers. Currently, high-end equipment is developing towards high power and small size. Gears and bearings, as key components of mechanical transmission, are subjected to harsh operating conditions such as high temperature, high load, and high speed, as well as a gradually deteriorating lubrication environment. This makes micropitting increasingly prominent in the damage behavior of high-end equipment, especially in wind turbine units with impact loads and variable speeds, where micropitting has become one of the key factors affecting their service life.

[0003] There are two main measures for controlling and preventing micropitting. One is to focus on materials metallurgy and gear processing technology, utilizing heat treatment processes such as hardening, carburizing, grinding, induction hardening, and nitriding, while simultaneously improving the bending and contact strength of the gears and reducing the surface roughness of the machined gear surfaces, thereby controlling the tendency for micropitting to occur. The other is to improve the formulation of wind turbine lubricating oils from a lubrication perspective.

[0004] Currently, improvements to wind turbine lubricant formulations are mainly achieved through two aspects: additives and base oils. While commonly used additives like zinc dithiophosphate offer excellent anti-wear properties, they can hinder surface running-in, significantly increasing the risk of micropitting.

[0005] Therefore, there is a need to provide a new wind power lubricant with resistance to micropitting. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a wind turbine gear oil containing nano-copper with anti-micropitting properties, its preparation method, and its application. This wind turbine gear oil incorporates nano-copper into the base oil, thus resolving the micropitting damage problem present in wind turbine gears.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] A wind turbine gear oil containing nano-copper with anti-micropitting properties comprises a synthetic base oil and a nano-copper solution, wherein the amount of nano-copper solution added accounts for 0.5% to 2% of the wind turbine gear oil; wherein the nano-copper solution is obtained by dissolving modified nano-copper in an ether solvent, and the mass percentage of Cu in the nano-copper solution is ≥12%, and the kinematic viscosity of the synthetic base oil at 40°C is not less than 300 mmHg. 2 ·s -1 .

[0009] The synthetic base oil has a viscosity index of 170-180 and a pour point of -40-45℃.

[0010] The nano-copper is a dialkyl dithiophosphate modified nano-copper.

[0011] The preparation method of the above-mentioned wind turbine gear oil containing nano-copper with anti-micropitting properties includes the following steps:

[0012] S1: Add nano copper solution to synthetic base oil and perform preliminary mixing treatment to obtain a preliminary mixed solution;

[0013] S3: The preliminary mixed solution is subjected to a heating and mixing process;

[0014] S4: After cooling the mixed solution obtained in step S2 to room temperature, the wind turbine gear oil with anti-micropitting properties can be obtained.

[0015] The amount of the nano-copper solution added is 0.5% to 2% of the wind turbine gear oil.

[0016] The initial mixing process is achieved through mechanical stirring.

[0017] The heating and mixing process is carried out by constant temperature and uniform speed stirring at 60℃~80℃.

[0018] In step S1, the synthetic base oil is base oil Oil A.

[0019] The copper nanoparticles in the copper nanoparticle solution are dialkyl dithiophosphate modified copper nanoparticles, and the preparation steps of the dialkyl dithiophosphate modified copper nanoparticles are as follows:

[0020] Copper nitrate Cu(NO3)2 was dissolved in an organic solvent, and a reducing agent was added to carry out a reduction reaction to obtain a suspension. Dialkyl dithiophosphate was then added to the suspension, and after purification and washing, dialkyl dithiophosphate-modified copper nanoparticles were obtained.

[0021] The above-mentioned wind turbine gear oil containing nano-copper with anti-micropitting properties is used in wind turbine units.

[0022] The beneficial effects of this invention are as follows:

[0023] (1) In this invention, nano-copper is added to wind power gear oil. By controlling the performance parameters of the base oil, the nano-copper particles and the base oil work together to achieve rolling friction in some areas of the surface, thereby reducing tangential friction and slowing down the accumulation of local surface tensile stress, which can ultimately reduce the occurrence and expansion of surface micro-pitting.

[0024] (2) Compared with existing wind power gear oils, the nano-copper in the wind power gear oil of the present invention has a "micro-ball" effect that can generate rolling friction between friction pairs, reducing the coefficient of friction and avoiding further deterioration of friction and wear behavior. In addition, its physical deposition and self-repair function can effectively fill surface scratches and micro-pits, reducing the possibility of further expansion of surface damage.

[0025] (3) The wind power gear oil of the present invention has a wide range of applications and the preparation method is simple and easy to implement. Attached Figure Description

[0026] Figure 1 These are surface optical mirror images of the wind turbine gear oils prepared in Examples 1, 2, and the comparative examples of the present invention, taken from frictional experiments.

[0027] Figure 2 The graph shows the test results of the friction coefficient of the wind turbine gear oils prepared in Examples 1, 2 and the comparative examples of the present invention. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0029] Unless otherwise specified, the raw materials and equipment used in the following examples are all commercially available.

[0030] Example 1:

[0031] This embodiment provides a wind turbine gear oil with anti-micropitting properties, and its preparation method includes the following steps:

[0032] S0: Preparation of dialkyl dithiophosphate (DDP) modified copper nanoparticles. Copper nitrate Cu(NO3)2 was dissolved in n-decyl alcohol, and ascorbic acid, a reducing agent, was added. A reduction reaction was carried out under stirring to obtain a suspension. Then, dialkyl dithiophosphate (DDP) was added to the suspension and reacted for a certain period of time. The unbound DDP was separated by centrifugation or sedimentation. After washing, stable DDP-modified copper nanoparticles were obtained.

[0033] S1: Add 0.5 g of spherical nano-copper solution with an average particle size of 5-10 nm to 99.5 g of base oil (wind turbine gear oil Oil A) and perform preliminary mixing to obtain a preliminary mixed solution; specifically, stir at 1000 r / min for 10 minutes using a mechanical stirrer; wherein the nano-copper solution is obtained by dissolving the modified nano-copper obtained in step S0 in propylene glycol ethyl ether, and the mass percentage of the nano-copper solution is 15%;

[0034] S2: Heat the preliminary mixed solution to 60°C and stir for 20 minutes;

[0035] S3: After cooling the mixed solution obtained in step S2 to room temperature, a uniform and fine wind turbine gear oil with anti-micropitting properties can be obtained.

[0036] Example 2:

[0037] This embodiment provides a wind turbine gear oil with anti-micropitting properties, and its preparation method includes the following steps:

[0038] S0: Preparation of dialkyl dithiophosphate (DDP) modified copper nanoparticles. Copper nitrate Cu(NO3)2 was dissolved in n-decyl alcohol, and ascorbic acid, a reducing agent, was added. A reduction reaction was carried out under stirring to obtain a suspension. Then, dialkyl dithiophosphate (DDP) was added to the suspension and reacted for a certain period of time. The unbound DDP was separated by centrifugation or sedimentation. After washing, stable DDP-modified copper nanoparticles were obtained.

[0039] S1: Add 2 grams of nano-copper solution with an average particle size of 5-10 nm to 98 grams of base oil (wind power gear oil Oil A) and perform preliminary mixing treatment to obtain a preliminary mixed solution; specifically, use a mechanical stirrer to stir at 1200 r / min for 20 minutes; wherein the mass percentage of nano-copper solution is 20%, and the nano-copper solution used in this embodiment is obtained by dissolving the DDP-modified nano-copper obtained in step S0 in dipropylene glycol butyl ether (DPnB);

[0040] S2: Heat the preliminary mixed solution to 60°C and stir for 20 minutes;

[0041] S3: After cooling the mixed solution obtained in step S2 to room temperature, a uniform and fine wind turbine gear oil with anti-micropitting properties can be obtained.

[0042] Comparative example:

[0043] The wind turbine gear oil in this comparative example is 100 grams of the same base oil (wind turbine gear oil Oil A) prepared in Example 1.

[0044] The anti-micropitting performance of the wind power gear oils prepared in Examples 1 and 2, as well as the comparative wind power gear oils, was evaluated using a TE77 reciprocating friction tester. The anti-micropitting performance of the lubricating oils was determined by observing the damage morphology on the friction plate surface.

[0045] Micropitting test conditions: Test ball material: 52100, friction plate material: 17CrNiMo7-6, load: 100N, temperature: 100℃, frequency: 10Hz, number of cycles: 1 million cycles.

[0046] Figure 1 These are surface optical mirror images of the wind turbine gear oils prepared in Examples 1, 2, and the comparative examples of the present invention, obtained from friction experiments. Figure 1 It is known that the friction test specimens under the lubrication conditions of Oil A for wind turbine gear oil exhibited severe surface damage, with wide surface wear tracks and large-area micropitting damage, which could potentially evolve into severe destructive behaviors such as spalling and fracture. In contrast, the products obtained in Examples 1 and 2 demonstrated excellent resistance to micropitting. The addition of nano-copper significantly reduced the area of ​​surface micropitting damage. Furthermore, although Example 2 had a higher nano-copper additive content than Example 1, the friction performance was similar, indicating that nano-copper can efficiently adsorb onto the surface for protection, and that more nano-copper particles cannot directly contact the surface to exert their effect. The presence of a lower micropitting area on the surface indicates that the "micro-ball" effect of nano-copper effectively reduced surface friction, and the adsorption of nano-copper particles on the surface filled some of the micropitting pits, alleviating the degree of surface micropitting damage.

[0047] Figure 2 The coefficient diagram shows the wind turbine gear oils prepared in Examples 1, 2, and the comparative examples of the present invention. Figure 2It can be seen that there are significant differences in the coefficient of friction under the three lubrication conditions. In the comparative example, due to the lack of additives, severe micropitting damage occurred on the surface, resulting in a consistently high coefficient of friction. In contrast, the coefficients of friction in Examples 1 and 2 are relatively low and gradual. In Example 1, the coefficient of friction is extremely flat in the early stage, but later, possibly due to the insufficient amount of nano-copper added, the insufficient effect of nano-copper led to a large fluctuation in the coefficient of friction. However, the coefficient of friction in Example 2 decreased gradually, which is related to the "micro-ball" rolling friction effect formed by the nano-copper particles adhering to the surface. This reduces the coefficient of friction, and the reduction in surface tangential stress can decrease the rate of accumulation of surface plastic deformation, thereby slowing down the occurrence of micropitting.

[0048] The above results fully demonstrate that the nano-copper wind turbine gear oil provided by this invention has excellent anti-micropitting properties.

[0049] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0050] The parts of this invention not described in detail are well-known in the art. The above embodiments are provided merely for the purpose of describing the invention and are not intended to limit the scope of the invention. The scope of the invention is defined by the appended claims. All equivalent substitutions and modifications made without departing from the spirit and principles of the invention should be covered within the scope of the invention.

Claims

1. A wind turbine gear oil containing nano-copper with anti-micropitting properties, characterized in that, The wind turbine gear oil comprises a synthetic base oil and a nano-copper solution, wherein the amount of nano-copper solution added accounts for 0.5% to 2% of the wind turbine gear oil. The nano-copper solution is obtained by dissolving modified nano-copper in an ether solvent, wherein the mass percentage of Cu in the nano-copper solution is ≥12%, and the kinematic viscosity of the synthetic base oil at 40°C is not less than 300 mmHg. 2 ·s -1 .

2. The wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 1, characterized in that, The synthetic base oil has a viscosity index of 170~180 and a pour point of -40~-45℃.

3. The wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 2, characterized in that, The nano-copper is nano-copper modified with dialkyl dithiophosphate.

4. The method for preparing the wind turbine gear oil containing nano-copper with anti-micropitting properties according to any one of claims 1 to 3, characterized in that, Includes the following steps: S1: Add nano copper solution to synthetic base oil and perform preliminary mixing treatment to obtain a preliminary mixed solution; S2: The preliminary mixed solution is subjected to a heating and mixing process; S3: After cooling the mixed solution obtained in step S2 to room temperature, the wind turbine gear oil with anti-micropitting properties can be obtained.

5. The method for preparing a wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 4, characterized in that, The amount of the nano-copper solution added is 0.5% to 2% of the wind turbine gear oil.

6. The method for preparing a wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 4, characterized in that, The initial mixing process is achieved through mechanical stirring.

7. The method for preparing a wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 4, characterized in that, The heating and mixing process is carried out by constant temperature and uniform speed stirring at 60℃~80℃.

8. The method for preparing wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 4, characterized in that, The synthetic base oil mentioned in step S1 is base oil Oil A.

9. The method for preparing a wind turbine gear oil containing nano-copper with anti-micropitting properties according to claim 4, characterized in that, The nano-copper in the nano-copper solution is dialkyl dithiophosphate modified nano-copper, and the preparation steps of the dialkyl dithiophosphate modified nano-copper are as follows: Copper nitrate Cu(NO3)2 was dissolved in an organic solvent, and a reducing agent was added to carry out a reduction reaction to obtain a suspension. Dialkyl dithiophosphate was then added to the suspension, and after purification and washing, dialkyl dithiophosphate-modified copper nanoparticles were obtained.

10. The application of the wind turbine gear oil containing nano-copper with anti-micropitting properties as described in any one of claims 1 to 3 in wind turbine units.

Images