CN113930272B

CN113930272B - Lubricating grease composition for automobile ball type one-way clutch and preparation method and application thereof

Info

Publication number: CN113930272B
Application number: CN202111261576.XA
Authority: CN
Inventors: 申明主; 童刘; 周伟东; 姚晓菲
Original assignee: China Petroleum and Chemical Corp
Current assignee: China Petroleum and Chemical Corp
Priority date: 2021-10-28
Filing date: 2021-10-28
Publication date: 2023-08-25
Anticipated expiration: 2041-10-28
Also published as: CN113930272A

Abstract

The invention relates to the technical field of lubricating grease, in particular to a lubricating grease composition for an automobile ball type one-way clutch, and a preparation method and application thereof. The grease composition comprises: base oils and solids; the base oil comprises silicone oil; the solid agent comprises phosphate; the silicone oil accounts for 1/2 to 3/4 of the base oil, and the phosphate accounts for 1/3 to 2/3 of the solid agent; the mass ratio of the base oil to the solid agent is (8-12): (1-2). The invention aims at improving lubricating grease, adopts base oil mainly comprising silicone oil, and additionally adds phosphorus salt as a solid agent to prepare the lubricating grease composition with larger friction coefficient.

Description

Lubricating grease composition for automobile ball type one-way clutch and preparation method and application thereof

Technical Field

The invention relates to the technical field of lubricating grease, in particular to a lubricating grease composition for an automobile ball type one-way clutch, and a preparation method and application thereof.

Background

The types of one-way clutches of automobile starters include ball-type one-way clutches, friction plate one-way clutches and spring one-way clutches. The tendency of friction plate type isolator to gradually decrease is eliminated from the production trend of the current starter. This is due to the fact that the friction plate has a complicated structure, and the manufacturing process of the friction plate is highly required, and the friction plate is liable to slip during use. The structure of the ball-type one-way clutch has been ninety years old, but the development of the ball-type one-way clutch is controversial particularly in automobile starters, for example, the ball-type one-way clutch is only applicable to starters with less than 4 horsepower in the aspects of the specifications of automobile electric equipment in the countries of the soviet union and eastern European countries. But in recent years, whether from theoretical analysis or development in production practice, it has been demonstrated that the ball-type one-way clutch is suitable for both low horsepower and high horsepower starters. Roller unions have been used in large numbers by many automotive manufacturers for starters of 10 horsepower or more.

At present, the ball type one-way clutch is widely applied to household automobiles due to the fact that the ball type one-way clutch is simple in structure and stable in performance, however, researches on the ball type one-way clutch in the prior art are still not thorough, researches on lubricating grease applied to the ball type one-way clutch of an automobile starter are not sufficient, and the lubricating grease capable of meeting the requirements of the ball type one-way clutch is lacking.

Disclosure of Invention

In order to solve the problems in the prior art, the invention provides a lubricating grease composition, a preparation method and application thereof, wherein the lubricating grease composition is prepared by adopting base oil mainly containing silicone oil and additionally adding phosphorus salt as a solid agent, and the lubricating grease composition with a larger friction coefficient can effectively prolong the service life of a ball-type one-way clutch of a starter.

In a first aspect, the present invention provides a grease composition comprising: base oils and solids;

the base oil comprises silicone oil; the solid agent comprises phosphate;

the silicone oil accounts for 1/2 to 3/4 of the base oil, and the phosphate accounts for 1/3 to 2/3 of the solid agent; the mass ratio of the base oil to the solid agent is (8-12): (1-2).

Preferably (10 to 12): (1-2).

The one-way clutch of the starter is used for reliably transmitting torque generated by the starter to a crankshaft of the engine and protecting a starter armature from being damaged due to high speed caused by overrunning by one-way action of the crankshaft and the engine during starting. Therefore, the performance of the isolator determines the reliability of the starter. The impact load is very large at the moment when the driving gear of the starter is meshed with the flywheel gear ring; and is required to withstand the start-stop endurance test and the low-temperature braking impact test more than 25 ten thousand times, so that the grease is required to have better capability of resisting impact load and longer service life.

There is less disclosure of grease related techniques required for the starter at present. According to the invention, through a large number of researches and summary of regular experience, the lubrication principle of the one-way clutch of the starter and the basic performance of the lubricating grease product are mastered, and the fact that the lubricating grease is not required to have a smaller friction coefficient like other structures for the ball-type one-way clutch of the starter, but rather has a larger friction coefficient is found, so that the ball can be firmly clamped with the shell when pushed into a narrower part of the wedge-shaped groove by the cross block, and further the engine is driven to rotate. However, the friction coefficient cannot be too high, which would adversely affect the performance of the ball-type one-way clutch of the starter. In accordance with the principles of the findings described above, the present invention provides a grease composition in which the friction coefficient of the grease is raised to a suitable range by a base oil containing silicone oil as a main component and a phosphate is added to the grease composition. Further, the silicone oil accounts for 1/2 to 3/4 of the base oil, and the phosphate accounts for 1/2 to 2/3 of the solid agent.

Further, the silicone oil is one or more of dimethyl silicone oil, ethyl silicone oil or phenyl silicone oil, preferably phenyl silicone oil; the phosphate is one or more of zinc phosphate, lithium phosphate or aluminum phosphate, preferably zinc phosphate.

In practical application, phenyl silicone oil has better effect in use, so that the lubricating grease has proper friction coefficient, and has better load resistance and service life when being used with other components in a compound way.

Further, the base oil has a kinematic viscosity of 70.0-120.0 mm at 40 DEG C ² And/s, the low-temperature pour point is not higher than-50 ℃.

Further, the base oil also comprises ester oil or ether oil; the solid agent also includes calcium carbonate or melamine cyanurate.

The base oil can adopt ester oil or ether oil such as dihydric alcohol ester, polyhydric alcohol ester, pentaerythritol ester or alkyl diphenyl ether besides silicone oil, so that the base oil meets the low temperature resistance, oxidation resistance and service life requirements of the ball type one-way clutch and has proper friction coefficient. In summary, the invention ensures that the service temperature of the grease product reaches-50 ℃ to 180 ℃ by improving the composition of the base oil in the grease, and has excellent oxidation resistance, long service life and larger friction coefficient. And on the basis, a proper solid agent is selected, so that the friction coefficient of the product is maintained in a proper range besides the excellent anti-impact load capacity and the rust resistance.

Further, the lubricating grease composition comprises, by weight, 50-80 parts of the base oil, 2-5 parts of lithium hydroxide, 5-18 parts of a thickening agent, 1-5 parts of an antioxidant, 1-10 parts of an antirust agent, 1-10 parts of an extreme pressure agent and 5-20 parts of a solid agent.

Preferably, the lubricating grease composition comprises 64-75 parts of base oil, 2.5-3.5 parts of lithium hydroxide, 10.5-13.5 parts of thickening agent, 2-3 parts of antioxidant, 1-2 parts of rust inhibitor, 1-2 parts of extreme pressure agent and 8-12 parts of solid agent.

Further, the thickener consists of fatty acid and dibasic acid, wherein the mass ratio of the fatty acid to the dibasic acid is (8-10): (2.5-3.5);

the antioxidant comprises amine and phenol, wherein the mass ratio of the amine to the phenol is 1: (0.5-2);

the antirust agent is sodium nitrite or sulfonate;

the extreme pressure agent is sulfurized olefin or DMTD extreme pressure agent.

Further, the fatty acid is one or two of dodecahydroxystearic acid and hydrogenated castor oil; the dibasic acid is one or more of azelaic acid, sebacic acid or adipic acid; the amine is one or two of aniline and naphthylamine; the phenol is hindered phenol; the sulfonate is one or more of calcium petroleum sulfonate, zinc dinonyl naphthalene sulfonate, barium dinonyl naphthalene sulfonate or sodium petroleum sulfonate.

In a second aspect, the present invention provides a method of preparing the grease composition comprising:

mixing a thickening agent, part of base oil and lithium hydroxide, and performing saponification reaction;

then adding the rest base oil, and keeping the temperature at 175-185 ℃ for 20-30 min;

further adding antioxidant, solid agent, extreme pressure agent and antirust agent.

Further, the lithium hydroxide is mixed in the form of alkali liquor, and the mass ratio of deionized water to lithium hydroxide is (4-6): 1.

further, the saponification reaction is to add 30% -50% alkali liquor and react for 0.5-1 hour at 90-100 ℃; adding the rest alkali liquor, and continuing the reaction for 1 to 1.5 hours; after the reaction is finished, keeping the temperature at 135-140 ℃ for 30-40 min, and keeping the temperature at 205-208 ℃ for 3-5 min;

further, the antioxidant, the solid agent, the extreme pressure agent and the rust inhibitor are added under the condition of 150-155 ℃ and under the condition of below 80 ℃.

Further, the present invention further provides the use of the grease composition as a grease for a ball-type one-way clutch.

As a preferred embodiment, the present invention provides a method for preparing a grease composition comprising:

(1) Preparing lithium hydroxide monohydrate into alkali liquor by using deionized water at 80-90 ℃, wherein the mass of water is 4-6 times of that of the lithium hydroxide monohydrate;

(2) Adding fatty acid and dibasic acid into 1/2-2/3 base oil, mixing and heating to 85-95 ℃; after the fatty acid is dissolved, 30-50% of the prepared alkali liquor is added, the temperature is controlled at 90-100 ℃, and the saponification reaction is carried out for 0.5-1.0 hour;

(3) After the saponification reaction is completed, adding residual alkali liquor, and continuing the reaction for 1.0-1.5 hours; heating to 135-140 ℃ after the reaction is completed, and keeping the temperature for 30-40 minutes;

(4) Heating to 205-208 deg.c and maintaining for 3-5 min;

(5) Adding the rest base oil, and keeping the temperature at 175-180 ℃ for 20-30 minutes;

(6) Cooling to 150-155 deg.c, adding antioxidant and solid agent, cooling to below 80 deg.c, and adding extreme pressure agent and antirust agent successively.

The invention has the following excellent effects:

the invention adopts the base oil which takes silicone oil as the main component, and additionally adds the phosphorus salt as the solid agent to prepare the lubricating grease composition with larger friction coefficient, and the lubricating grease composition is particularly suitable for the ball type one-way clutch of the starter, thereby effectively improving the durability.

In addition, the lubricating grease composition provided by the invention has excellent performance on various indexes, and is concretely as follows:

1) The lubricating grease provided by the invention has excellent starting performance, and the starting torque is less than or equal to 500 mN.m at 50 ℃ below zero by adopting an SH/T0338 standard method.

2) The lubricating grease provided by the invention has excellent shearing resistance, and the difference between the 10-ten-thousand-time prolonged working cone penetration and the 60-time working cone penetration is less than or equal to 30 (0.1 mm) by adopting a GB/T269 method.

3) The lubricating grease provided by the invention has good rust resistance, and all bearings are rust-free by using GB/T5018 test.

4) The lubricating grease provided by the invention has excellent extreme pressure performance, and the extreme pressure performance (four-ball machine method) P is tested by SH/T0202 _D The value is more than or equal to 4904N.

5) The lubricating grease provided by the invention has excellent oxidation resistance, and is tested by SH/T0790, and the oxidation induction period (210 ℃ C., O) ₂ The flow rate is 100ml/min, the pressure is 3.50 MPa) is more than or equal to 120min.

6) The lubricating grease prepared by the invention has a proper friction coefficient, and the friction coefficient (400N, 80 ℃, 50HZ and 1.0 mm) is in the range of 0.30-0.40 by adopting an ASTM D5707 test.

7) The number of times of endurance test of the one-way clutch of the starting motor exceeds 25 ten thousand times, parts are not worn, and the low-temperature braking test has no slipping phenomenon.

Detailed Description

The following examples are illustrative of the invention and are not intended to limit the scope of the invention.

Example 1

The embodiment provides a lubricating grease composition for an automobile ball type one-way clutch, which comprises the following components in parts by weight:

8 parts of dodecahydroxystearic acid, 2.5 parts of azelaic acid, 2.5 parts of lithium hydroxide, 2 parts of an antioxidant, 1 part of an antirust agent, 1 part of an extreme pressure agent, 8 parts of a solid agent and 70 parts of base oil.

Wherein the antioxidant is a mixture of aniline and hindered phenol, and the mass ratio of the aniline to the hindered phenol is 1:1; the rust inhibitor is sodium nitrite; the extreme pressure agent is sulfurized olefin; the solid agent is a mixture of calcium carbonate and phosphate, and the mass ratio of the calcium carbonate to the phosphate is 1:1; the base oil is a mixture of pentaerythritol ester and phenyl silicone oil, and the mass ratio is 1:1.

The composition is prepared into lubricating grease by the following method:

(1) The lithium hydroxide monohydrate is prepared into alkali liquor by hot water at 80 ℃, and the mass of the water is 5 times that of the lithium hydroxide monohydrate.

(2) Adding the dodecahydroxystearic acid and the azelaic acid into 2/3 base oil, mixing and heating to 85 ℃; after the fatty acid is dissolved, 40% of the prepared alkali liquor is added, the temperature is controlled at 80 ℃, and the saponification reaction is carried out for 0.5 hour.

(3) After the saponification reaction is completed, adding the rest alkali liquor, and continuing the reaction for 1.0 hour; after the reaction is completed, the temperature is raised to 135 ℃ and kept constant for 30 minutes.

(4) After the constant temperature is completed, the temperature is raised to 205 ℃ and kept for 3 minutes.

(5) After the constant temperature is finished, adding the residual base oil, and keeping the constant temperature at 175 ℃ for 20 minutes.

(6) Cooling after finishing constant temperature, adding an antioxidant and a solid agent at 150 ℃, continuously cooling to below 80 ℃, sequentially adding an extreme pressure agent and an antirust agent, uniformly stirring, rolling oil by a three-roller machine, and filling.

Example 2

10 parts of dodecahydroxystearic acid, 3.5 parts of sebacic acid, 3.5 parts of lithium hydroxide, 3 parts of an antioxidant, 2 parts of an antirust agent, 2 parts of an extreme pressure agent, 12 parts of a solid agent and 64 parts of base oil.

Wherein the antioxidant is a mixture of naphthylamine and hindered phenol, and the mass ratio of the naphthylamine to the hindered phenol is 1:1; the rust inhibitor is sulfonate; the extreme pressure agent is DMTD dimer; the solid agent is a mixture of melamine cyanurate and phosphate, and the mass ratio of the melamine cyanurate to the phosphate is 1:1; the base oil is a mixture of polyol ester and methyl phenyl silicone oil, and the mass ratio is 1:1.

The composition is prepared into lubricating grease by the following method:

(1) The lithium hydroxide monohydrate is prepared into alkali liquor by hot water at 90 ℃, and the mass of the water is 5 times that of the lithium hydroxide monohydrate.

(2) Adding the dodecahydroxystearic acid and the sebacic acid into 2/3 base oil, and mixing and heating to 95 ℃; after the fatty acid is dissolved, 40% of the prepared alkali liquor is added, the temperature is controlled at 100 ℃, and the saponification reaction is carried out for 1 hour.

(3) After the saponification reaction is completed, adding the rest alkali liquor, and continuing the reaction for 1.5 hours; after the reaction is completed, the temperature is raised to 140 ℃ and the temperature is kept constant for 40 minutes.

(4) After the constant temperature is finished, the temperature is raised to 208 ℃ and kept for 5 minutes.

(5) After the constant temperature is finished, adding the residual base oil, and keeping the temperature at 180 ℃ for 30 minutes.

(6) Cooling after finishing constant temperature, adding an antioxidant and a solid agent at 155 ℃, continuously cooling to below 80 ℃, sequentially adding an extreme pressure agent and an antirust agent, uniformly stirring, rolling oil by a three-roller machine, and filling.

Test example 1

The test example tests various properties of the grease composition prepared in examples 1-2, and the following results were obtained:

table 1 results of grease performance tests for various examples

As shown in the above table, examples 1 and 2 of the present invention provide grease compositions that are acceptable in terms of each performance, especially 25 ten thousand starter endurance tests, demonstrating that the grease compositions provided by the present invention are suitable for the requirements of a ball-type one-way clutch of a starter.

Test example 2

The test example further provides a comparison of the effects of various grease combinations involved in the research process, specifically including:

grease composition 3: 8 parts of dodecahydroxystearic acid, 2.5 parts of azelaic acid, 2.5 parts of lithium hydroxide, 2 parts of an antioxidant, 1 part of an antirust agent, 1 part of an extreme pressure agent, 8 parts of a solid agent and 70 parts of base oil.

Wherein the antioxidant is a mixture of aniline and hindered phenol, and the mass ratio of the aniline to the hindered phenol is 1:1; the rust inhibitor is sodium nitrite; the extreme pressure agent is sulfurized olefin; the solid agent is a mixture of calcium carbonate and melamine cyanurate, and the mass ratio of the calcium carbonate to the melamine cyanurate is 1:1; the base oil is a mixture of pentaerythritol ester and phenyl silicone oil, and the mass ratio is 1:1.

Grease composition 4: 8 parts of dodecahydroxystearic acid, 2.5 parts of azelaic acid, 2.5 parts of lithium hydroxide, 2 parts of an antioxidant, 1 part of an antirust agent, 1 part of an extreme pressure agent, 8 parts of a solid agent and 70 parts of base oil.

Wherein the antioxidant is a mixture of aniline and hindered phenol, and the mass ratio of the aniline to the hindered phenol is 1:1; the rust inhibitor is sodium nitrite; the extreme pressure agent is sulfurized olefin; the solid agent is a mixture of calcium carbonate and phosphate, and the mass ratio of the calcium carbonate to the phosphate is 1:1; the base oil is a mixture of glycol ester and ethyl silicone oil, and the mass ratio is 1:1.

Grease composition 5: 8 parts of hydrogenated castor oil, 2.5 parts of adipic acid, 2.5 parts of lithium hydroxide, 2 parts of an antioxidant, 1 part of an anti-rust agent, 1 part of an extreme pressure agent, 8 parts of a solid agent and 70 parts of base oil.

Grease composition 6: 8 parts of dodecahydroxystearic acid, 2.5 parts of azelaic acid, 2.5 parts of lithium hydroxide, 2 parts of an antioxidant, 1 part of an antirust agent, 1 part of an extreme pressure agent, 4 parts of a solid agent and 74 parts of base oil.

Wherein the antioxidant is a mixture of aniline and hindered phenol, and the mass ratio of the aniline to the hindered phenol is 1:1; the rust inhibitor is sodium nitrite; the extreme pressure agent is sulfurized olefin; the solid agent is a mixture of calcium carbonate and phosphate, and the mass ratio of the calcium carbonate to the phosphate is 1:1; the base oil is a mixture of glycol ester and simethicone, and the mass ratio is 1:1.

This test example was conducted on the grease compositions obtained in examples 1 and 2, and the lubricating experiments of the starter ball one-way clutch by the above grease composition, and all the grease compositions were prepared in the same manner as in example 1, with the following results:

table 2 results of grease performance tests for various examples

As can be seen from table 2, in the grease composition 3 of test example 2, the friction coefficient of the product becomes significantly smaller when no phosphate is used, and the slipping phenomenon occurs in the starter endurance test; when ethyl silicone oil is used in the lubricating grease composition 4, the friction coefficient of the product is obviously increased to be more than 0.40, and the starter endurance test shows that the component is not slipped, but the abrasion phenomenon occurs; when the grease composition 5 is used for preparing the thickening agent by using different dibasic acids, the shearing resistance of the product is poor, meanwhile, the friction coefficient is reduced, and the slipping phenomenon occurs in the starter endurance test; when the proportion of the simethicone to the solid agent is reduced in the lubricating grease composition 6, the friction coefficient of the product is obviously reduced, and the slipping phenomenon occurs in the starter endurance test. By comparing the results of test example 1 and test example 2, it is highlighted that the product prepared when benzyl silicone oil is used as a base oil component, azelaic acid or sebacic acid is used as a dibasic acid, and calcium carbonate and phosphate are used as solid agents, has excellent impact load resistance, shear resistance, long endurance life, and the like.

While the invention has been described in detail in the foregoing general description and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that modifications and improvements can be made thereto. Accordingly, such modifications or improvements may be made without departing from the spirit of the invention and are intended to be within the scope of the invention as claimed.

Claims

1. A grease composition, comprising:

50-80 parts of base oil, 2-5 parts of lithium hydroxide, 5-18 parts of thickening agent, 1-5 parts of antioxidant, 1-10 parts of antirust agent, 1-10 parts of extreme pressure agent and 5-20 parts of solid agent;

the base oil comprises phenyl silicone oil and ester oil or ether oil; the phenyl silicone oil accounts for 1/2 to 3/4 of the base oil in terms of mass ratio;

the solid agent comprises phosphate, calcium carbonate or melamine cyanurate; the phosphate accounts for 1/3 to 2/3 of the solid agent; the mass ratio of the base oil to the solid agent is (8-12): (1-2); the phosphate is one or more of zinc phosphate or aluminum phosphate;

the kinematic viscosity of the base oil at 40 ℃ is 70.0-120.0 mm ² S, the low temperature pour point is not higher than-50 ℃;

the thickener consists of fatty acid and dibasic acid, wherein the mass ratio of the fatty acid to the dibasic acid is (8-10): (2.5-3.5); the antioxidant comprises amine and phenol, wherein the mass ratio of the amine to the phenol is 1: (0.5-2), wherein the antirust agent is sodium nitrite and/or sulfonate; the extreme pressure agent is sulfurized olefin or DMTD extreme pressure agent.

2. The grease composition of claim 1, wherein the phosphate is zinc phosphate.

3. The grease composition according to claim 1, characterized by comprising, in parts by weight: 64-75 parts of base oil, 2.5-3.5 parts of lithium hydroxide, 10.5-13.5 parts of thickening agent, 2-3 parts of antioxidant, 1-2 parts of antirust agent, 1-2 parts of extreme pressure agent and 8-12 parts of solid agent.

4. The grease composition of claim 1, wherein the fatty acid is one or both of dodecahydroxystearic acid, hydrogenated castor oil; the dibasic acid is one or more of azelaic acid, sebacic acid or adipic acid; the amine is one or two of aniline and naphthylamine; the phenol is hindered phenol; the sulfonate is one or more of calcium petroleum sulfonate, zinc dinonyl naphthalene sulfonate, barium dinonyl naphthalene sulfonate or sodium petroleum sulfonate.

5. A method of preparing a grease composition according to any one of claims 1 to 4, comprising:

6. Use of a grease composition according to any one of claims 1-4 as a grease for a ball-type one-way clutch.