Energy-saving lubricating grease

Abstract

The invention relates to energy-saving lubricating grease. The lubricating grease disclosed by the invention is prepared from the following components in parts by weight: 3 to 15 parts of polypropylene hydrocarbon thickening agent, 70 to 95 parts of base oil (Mobil MAX 3.5 or English Durasyn 136), 1 to 3 parts of organic molybdenum, 1 to 3 parts of ZDDP, 1 to 2 parts of nano graphene, 0.5 to 2 parts of antioxidant, 0.05 to 0.1 part of defoaming agent and 0.5 to 1 part of antirust agent. The lubricating grease is suitable for low-temperature and high-temperature conditions at the same time, the friction coefficient can be effectively reduced, and the energy consumption of friction heat production is reduced.

Description

Technical Field

[0001] The invention belongs to the field of lubricating grease, and specifically relates to an energy-saving lubricating grease, in particular to an energy-saving RV reducer lubricating grease. Background Art

[0002] Grease is a semi-solid or solid lubricant composed of liquid lubricant (base oil), thickener and additives. Thickeners can generally use metal soaps such as lithium soap and calcium soap of higher fatty acids. Thickeners for high-temperature grease can use various complex soaps and polyurea compounds. Others include high molecular compounds such as polytetrafluoroethylene. The base oil is mainly mineral oil, and there are also synthetic oils such as ester oil, polyglycol, silicone oil, etc. Additives can be added as needed. Antioxidants to inhibit the oxidation and aging of grease, extreme pressure agents such as sulfur and phosphorus compounds for the purpose of improving lubricity, and oiliness agents such as higher fatty acids.

[0003] Patent document CN111996063A discloses a high temperature resistant industrial robot RV reducer grease and its preparation method. The grease is prepared by special process with polyether and ester as base oil, tetraurea and composite calcium sulfonate as thickener, antioxidant, extreme pressure anti-wear agent, rust inhibitor, anti-foam agent, etc., but the structure of the product becomes complicated after the two soaps of tetraurea and composite calcium sulfonate are mixed, and it is difficult to achieve reproducibility and stability, so the effect stability of the product is not strong. CN106497652A introduces a robot grease with extremely low friction coefficient and good lubrication performance, but the traditional metal lithium soap-based grease has high power consumption due to competitive adsorption between its thickener and additives.

[0004] The present invention is the first to design an energy-saving RV reducer grease by comprehensively considering thickeners and additives. The non-polar polypropylene hydrocarbon is used as the thickener, which solves the contradiction of competitive adsorption between conventional thickeners and additives, and the thickener has very good compatibility with the base oil, and the additives are easy to reach the metal surface, achieving energy-saving effects. At the same time, the three coordinated organic molybdenum, alkyl dithiophosphate zinc (ZDDP), and nanographene extreme pressure anti-wear agent are used to reduce the friction coefficient, and the friction coefficient can be as low as 0.022, reducing the energy consumption of friction heat generation, which is beneficial to energy saving. In addition, the use of high flash point and low volatility special base oil (when V100 viscosity is 3.5, the flash point is greater than 200 degrees, and the Noack (250°C) loss is less than 13%) (Mobil MAX 3.5 or INEOS Durasyn 136) gives the product excellent high and low temperature performance, showing excellent flow performance and low temperature torque at low temperature, and excellent low volatility and colloidal stability at high temperature. Summary of the invention

[0005] The purpose of the present invention is to provide an energy-saving lubricating grease in view of the problems existing in the prior art.

[0006] The lubricating grease of the present invention, at least one of the additives used, can easily adhere to the metal surface at high and low temperatures to reduce the friction coefficient. The additive of the present invention adopts a combination of organic molybdenum, ZDDP, and nanographene. ZDDP can act at high temperatures, nanographene can act at low temperatures, and organic molybdenum can act under heavy loads. The three work together to make the lubricating grease of the present invention suitable for both low and high temperature conditions, and can effectively reduce the friction coefficient and reduce the energy consumption of frictional heat generation.

[0007] The purpose of the present invention can be achieved by the following scheme:

[0008] The present invention provides an energy-saving lubricating grease, comprising the following components in parts by weight:

[0009]

[0010] As an embodiment of the present invention, the flash point of the base oil is greater than 200 degrees, and the volatility (Noack volatility test, 250° C.) is less than 13%.

[0011] As an embodiment of the present invention, the base oil is one or more of MAX 3.5 and Durasyn 136. MAX 3.5: 100 degree viscosity 3.5 cSt, flash point 226°C, volatility 11.2%.

[0012] As one embodiment of the present invention, the base oil is preferably 70-90 parts; the polypropylene hydrocarbon is preferably 5-15 parts.

[0013] As one embodiment of the present invention, the antioxidant is alkylated PANA, N,N 1 - one or more of di-sec-butyl-p-phenylenediamine.

[0014] As an embodiment of the present invention, the rust inhibitor is one or more of barium petroleum sulfonate, calcium petroleum sulfonate, and magnesium petroleum sulfonate.

[0015] As an embodiment of the present invention, the defoaming agent is one or more of dimethyl silicone oil, homopolymer or copolymer of acrylate, and homopolymer or copolymer of methacrylate.

[0016] The present invention also provides a method for preparing the energy-saving grease, comprising the following steps: adding an antioxidant to the base oil, stirring and heating, adding polypropylene hydrocarbon, and stirring evenly; adding the remaining components after cooling, and stirring evenly to obtain the energy-saving grease.

[0017] As one embodiment of the present invention, the stirring and heating temperature is 200-210° C., and the stirring time is 1-3 h.

[0018] As one embodiment of the present invention, the remaining components are added after the temperature is lowered to 65-75°C.

[0019] The present invention also provides an application of the energy-saving lubricating grease in robot reduction gears and robot arm joints. The energy-saving lubricating grease of the present invention can be used for reduction gears and arm joints with very complex lubrication procedures to improve performance and extend service life.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] (1) The present invention uses polypropylene hydrocarbon as a thickener, which solves the competition contradiction between conventional thickeners and additives (organic molybdenum, ZDDP, nanographene). The thickener of the present invention has no competition relationship at high and low temperatures. The three additives of the present invention coordinate to reduce the friction coefficient, and the friction coefficient can be as low as 0.022, reducing the energy consumption of frictional heat generation, which is beneficial to energy saving.

[0022] (2) The thickener of the present invention has very good compatibility with the base oil. Under high temperature conditions, it can make the alkyl dithiophosphate zinc easily reach the metal surface and play a role at high temperature; under low temperature conditions, it can make the nanographene easily reach the metal surface and play a role at low temperature; under heavy load conditions, it can make the organic molybdenum easily reach the metal surface and play a role; that is, the thickener of the present application can make the additives easily reach the metal surface under different conditions, achieving energy-saving effects.

[0023] (3) The use of high flash point and low volatility special base oil Mobil MAX 3.5 (or INEOS's Durasyn 136) gives the product excellent high and low temperature performance, showing excellent flow properties and low temperature torque at low temperatures, and excellent low volatility and colloid stability at high temperatures. DETAILED DESCRIPTION

[0024] The present invention is described in detail below in conjunction with specific embodiments. The following examples are implemented under the premise of the technical solution of the present invention, and provide detailed implementation methods and specific operation processes, which will help those skilled in the art to further understand the present invention. It should be pointed out that the protection scope of the present invention is not limited to the following embodiments, and several adjustments and improvements made under the premise of the concept of the present invention all belong to the protection scope of the present invention.

[0025] Examples 1-4

[0026] This embodiment provides an energy-saving grease, the parts of each component are shown in Table 1, and the preparation method is as follows:

[0027] Add antioxidant to the base oil, heat to 200-210°C, stir for 1 hour, add polypropylene, stir evenly; cool to 70°C within 10 minutes, add remaining components, stir evenly, and obtain the energy-saving grease.

[0028] Comparative Examples 1-7

[0029] This comparative example provides an energy-saving grease, the parts of each component are shown in Table 1, and the preparation method is as follows:

[0030] Add antioxidant to the base oil, heat to 200-210°C, stir for 1 hour, add polypropylene, stir evenly; cool to 70°C within 10 minutes, add remaining components, stir evenly, and obtain the energy-saving grease.

[0031] Table 1 Recipe

[0032]

[0033] Performance Testing

[0034] The grease obtained in the examples and comparative examples was tested, and the test methods are shown in Table 2 below:

[0035] Table 2

[0036]

[0037] The test results are shown in Table 3 below:

[0038] Table 3

[0039]

[0040] The thickener in Comparative Example 1 is lithium dodecyl stearate, which competes with the additives (organic molybdenum, ZDDP, nanographene), and the additives cannot play a coordinating role. When the additives reach the metal surface, the lubrication performance deteriorates, that is, the PB and PD values ​​deteriorate, and the SRV friction coefficient increases, and the effect cannot be exerted when the reducer is running.

[0041] In Comparative Example 2, no additive was used, and the lubrication performance was deteriorated.

[0042] The additives in Comparative Example 3 are organic molybdenum and nano-graphene, and the lubrication performance is improved compared with that in Comparative Example 2; but the lubrication performance is worse than that in Example 1; because the additives organic molybdenum and nano-graphene improve the lubrication performance, but compared with the combined effect of organic molybdenum, nano-graphene and alkyl dithiophosphate zinc, the lubrication performance is reduced.

[0043] The additives in Comparative Example 4 are organic molybdenum and alkyl zinc dithiophosphate, and the lubrication performance is improved compared with that in Comparative Example 2; but the lubrication performance is worse than that in Example 1; because the additives organic molybdenum and alkyl zinc dithiophosphate improve the lubrication performance, but compared with the combined effect of organic molybdenum, nanographene and alkyl zinc dithiophosphate, the lubrication performance is reduced.

[0044] The additives in Comparative Example 5 are nanographene and alkyl zinc dithiophosphate, and the lubrication performance is improved compared with that in Comparative Example 2; but the lubrication performance is worse than that in Example 1; because the additives nanographene and alkyl zinc dithiophosphate improve the lubrication performance, but compared with the combined effect of organic molybdenum, nanographene and alkyl zinc dithiophosphate, the lubrication performance is reduced.

[0045] The base oil in Comparative Example 6 is Class II base oil 150N, and its low temperature performance is inferior to that of Durasyn 136 or Max 3.5 in the examples, resulting in a large low temperature torque of the product.

[0046] In Comparative Example 7, alkyl zinc dithiophosphate was replaced by isobutylene sulfide, because isobutylene sulfide is more corrosive to metals than alkyl zinc dithiophosphate and has no synergistic effect with organic molybdenum and nanographene, resulting in a poor SRV friction coefficient compared with the example.

[0047] The thickener used in Example 1 is polypropylene hydrocarbon, which has very good compatibility with the base oil. The friction surface elements of Example 1 and Comparative Example 1 (the thickener is lithium dodecyl stearate) are tested under high temperature, low temperature and heavy load conditions, as shown in Table 4. Under high temperature conditions, the alkyl dithiophosphate zinc can easily reach the metal surface and play a role at high temperature; under low temperature conditions, the nanographene can easily reach the metal surface and play a role at low temperature; under heavy load conditions, the organic molybdenum can easily reach the metal surface and play a role.

[0048] Table 4

[0049]

[0050]

[0051] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art may make various modifications or variations within the scope of the claims, which do not affect the essence of the present invention.

Claims

1. An energy-saving grease, characterized in that: The composition comprises the following components in parts by weight:

2. The energy-saving grease according to claim 1, characterized in that: The base oil is 70-90 parts; the polypropylene hydrocarbon is 5-15 parts.

3. The energy-saving grease according to claim 1, characterized in that: The flash point of the base oil is greater than 200 degrees and the volatility is less than 13%; And / or, the base oil is one or more of MAX 3.5 and Durasyn 136.

4. The energy-saving grease according to claim 1, characterized in that: The antioxidant is alkylated PANA, N,N 1 - one or more of di-sec-butyl-p-phenylenediamine.

5. The energy-saving grease according to claim 1, characterized in that: The rust inhibitor is one or more of barium petroleum sulfonate, calcium petroleum sulfonate, and magnesium petroleum sulfonate.

6. The energy-saving grease according to claim 1, characterized in that: The defoaming agent is one or more of dimethyl silicone oil, homopolymer or copolymer of acrylate, and homopolymer or copolymer of methacrylate.

7. A method for preparing the energy-saving grease according to claim 1, characterized in that: The steps include: Add antioxidant to base oil, stir and heat, add polypropylene hydrocarbon, stir evenly; after cooling, add remaining components, stir evenly, and obtain the energy-saving grease.

8. The method for preparing energy-saving grease according to claim 7, characterized in that: The stirring and heating temperature is 200-210°C.

9. The method for preparing energy-saving grease according to claim 7, characterized in that: After cooling to 65-75°C, add the remaining ingredients.

10. Use of the energy-saving grease as claimed in claim 1 in robot reduction gears and robot arm joints.

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