Water-soluble lubricating liquid for hot rolling and preparation method thereof

Abstract

The present invention provides a water-soluble lubricant for hot rolling and a preparation method thereof, belonging to the field of rolling lubrication. The lubricant comprises the following components, measured by mass: 1% to 10% high-temperature grease; 0.4% to 4% Span 80; 0.05% to 0.075% diethanolamine oleate; 0.1% to 0.2% triethanolamine oleate; 0.01% to 0.05% bactericide; 0.1% to 1.5% Fe₃O₄ nanoparticles; the balance being water. The synergistic emulsification of Span 80 with diethanolamine oleate and triethanolamine oleate creates a stable, uniform liquid with excellent lubricity and cooling properties. The addition of a bactericide prevents deterioration of the lubricant due to microbial contamination; and the addition of Fe₃O₄ nanoparticles enhances the lubricating effect of the lubricant at high temperatures. Furthermore, the lubricant can be formulated to have varying concentrations and lubricating effects according to actual rolling requirements. The lubricant is simple and convenient to use, ensuring roller cooling while providing lubrication, and does not require a dedicated hot rolling oil supply system.

Description

Technical Field

[0001] The present application relates to the technical field of rolling lubrication, and in particular to a water-soluble lubricating fluid for hot rolling and a preparation method thereof. Background Art

[0002] During the hot rolling process, steel billets are exposed to temperatures ranging from 800°C to 1200°C, where they come into contact with the rolls and guides. This high temperature can easily lead to thermal friction damage. This is especially true for hot rolling mill rolls, where instantaneous surface temperatures can reach 500°C to 600°C. The rolling forces in the roughing mill can reach 50MPa to 150MPa, while those in the finishing mill can reach 100MPa to 500MPa. These factors can easily cause wear on the rolls and the workpiece surface. Lubrication is the most effective method for reducing friction and wear, and hot rolling process lubrication is widely used in hot-rolled thin plates, achieving excellent results.

[0003] Currently, the hot rolling oil used for lubrication in hot rolling processes is mostly an oil-water mixture. This is a non-uniform liquid created by mechanically mixing the hot rolling oil and water in a specialized mixer. This requires a dedicated process lubrication system, and during this process, several issues arise, including pipe and nozzle blockage, slow oil temperature increase, and limited improvement in rolling force. Therefore, there is an urgent need to develop a hot rolling lubricant that does not require a dedicated hot rolling oil supply system. Summary of the Invention

[0004] The present application provides a water-soluble lubricant for hot rolling and a preparation method thereof. A stable and uniform lubricant is formed by the synergistic emulsification of Span 80 with diethanolamine oleate and triethanolamine oleate, thereby achieving the goal of not requiring a special hot rolling oil supply system during the lubrication process of the hot rolling process.

[0005] In a first aspect, the present application provides a water-soluble lubricant for hot rolling, which is composed of the following components, measured by mass fraction: 1% to 10% high-temperature grease; 0.4% to 4% Span 80; 0.05% to 0.075% diethanolamine oleate; 0.1% to 0.2% triethanolamine oleate; 0.01% to 0.05% fungicide; 0.1% to 1.5% Fe3O4 nanoparticles, and the balance is water.

[0006] Optionally, the lubricating fluid is composed of the following components, measured by mass fraction: 2% high-temperature grease; 0.8% Span 80; 0.05% diethanolamine oleate; 0.15% triethanolamine oleate; 0.03% bactericide; 0.5% Fe3O4 nanoparticles, and the balance is water.

[0007] Optionally, the operating temperature of the high-temperature grease is ≥1000°C.

[0008] Optionally, the fungicide includes: 1,2-benzisothiazolin-3-one, 2-methylphenol-D8, dodecyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, dodecyldimethylbenzylammonium bromide, cyanoquaternary ammonium salt, polynitrogen heterocyclic quaternary ammonium salt, polyquaternary ammonium salt and diquaternary ammonium salt.

[0009] Optionally, the size of the Fe3O4 nanoparticles is 10nm~50nm.

[0010] In a second aspect, the present application provides a method for preparing a water-soluble lubricating liquid for hot rolling, the method being used to prepare the lubricating liquid according to any one embodiment of the first aspect, the method comprising:

[0011] Add high-temperature grease to Span 80, then heat and stir to obtain component A;

[0012] Add diethanolamine oleate, triethanolamine oleate and a fungicide into water, and then stir to obtain component B;

[0013] The component A, the component B and the Fe3O4 nanoparticle dispersion are added into water to obtain a water-soluble lubricating liquid for hot rolling.

[0014] Optionally, the heating temperature is 70°C~120°C.

[0015] Optionally, the mass ratio of Fe3O4 nanoparticles to water in the Fe3O4 nanoparticle dispersion is 1:(3-7).

[0016] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0017] The present application forms a stable and uniform liquid with good lubricity and cooling properties through the synergistic emulsification of Span 80, diethanolamine oleate and triethanolamine oleate; avoids the deterioration of the lubricating fluid due to microbial contamination by adding a bactericide; and improves the lubricating effect of the lubricating fluid at high temperatures by adding Fe3O4 nanoparticles.

[0018] In addition, the lubricating liquid in this application can be formulated into lubricating liquids with different concentrations and different lubricating effects according to actual rolling needs. It is simple and convenient to use, and has lubrication function while ensuring the cooling of the rollers, and does not require a special hot rolling oil supply system. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0020] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0021] Figure 1 A schematic flow chart of a method for preparing a water-soluble lubricating fluid for hot rolling provided in an embodiment of the present application. DETAILED DESCRIPTION

[0022] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0023] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity and should not be understood as a hard limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numbers within the range. For example, the description of a range from 1 to 6 should be considered to have specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which applies regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0024] In addition, in the description of the present application specification, the terms "including", "comprising", etc. mean "including but not limited to". In this article, relational terms such as "first" and "second" are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In this article, "at least one" means one or more, and "plurality" means two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c" or "at least one of a, b, and c" can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple.

[0025] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0026] In a first aspect, the present application provides a water-soluble lubricant for hot rolling, which is composed of the following components, measured by mass fraction: 1% to 10% high-temperature grease; 0.4% to 4% Span 80; 0.05% to 0.075% diethanolamine oleate; 0.1% to 0.2% triethanolamine oleate; 0.01% to 0.05% fungicide; 0.1% to 1.5% Fe3O4 nanoparticles, and the balance is water.

[0027] The lubrication mechanism of the hot rolling process in this application is specifically as follows: after the water-soluble lubricating liquid is sprayed onto the surface of the roller, the water evaporates rapidly, taking away a large amount of heat and playing a cooling role; the emulsifier and high-temperature grease burn in the deformation zone and decompose to produce residual carbon, separating the roller from the metal surface and forming a high-temperature, high-pressure air cushion, which plays a lubricating role in the form of gas.

[0028] The present application forms a stable and uniform liquid with good lubricity and cooling properties through the synergistic emulsification of Span 80, diethanolamine oleate and triethanolamine oleate; avoids the deterioration of the lubricating fluid caused by microbial contamination by adding a bactericide; and improves the friction coefficient of the lubricating fluid at high temperatures by adding Fe3O4 nanoparticles.

[0029] Controlling the high-temperature grease content to 1%-10% and the Span 80 content to 0.4%-4% has the positive effect of: within this ratio of Span 80 to grease, the grease can be completely dissolved in the Span 80. If the Span 80 content is reduced, the grease will precipitate. If the Span 80 content is increased, the grease content will be reduced, which is not conducive to improving the lubricating effect of the lubricant. The high-temperature grease content can be 1%, 2%, 3%, 5%, 7%, 9%, 10%, etc.; the Span 80 content can be 0.4%, 0.8%, 1.2%, 2.4%, 3.6%, 4%, etc.

[0030] Specifically, the high-temperature grease can be FUCHS GLEITMO820 high-temperature grease, Great Wall LW-1000 grease, Futerun HX-1000 white high-temperature grease, etc.

[0031] Controlling the triethanolamine oleate content to 0.1%-0.2% has positive effects: Triethanolamine oleate is a nonionic surfactant that diffuses in water to form an emulsion. It also utilizes its saponification reaction with oils and fats to increase the solubility of oily substances in water. Excessive addition can increase the pH value of the solution. While increasing triethanolamine can improve the water solubility of lubricants, its toxicity after oxidation requires minimal adjustment. The triethanolamine oleate content can be as low as 0.1%, 0.12%, 0.14%, 0.16%, 0.18%, or 0.2%.

[0032] The positive effect of controlling the content of diethanolamine oleate to 0.05% to 0.075% is that diethanolamine oleate forms loose micelles in aqueous solution, increasing the solubility of oil substances in the solution. It also works synergistically with triethanolamine oleate, reducing the concentration of triethanolamine oleate while improving the dispersibility of oils and fats. The content of diethanolamine oleate can be 0.05%, 0.055%, 0.060%, 0.065%, 0.075%, etc.

[0033] The positive effect of controlling the content of the bactericide to 0.01% to 0.05% is to prevent the organic components in the lubricant from being deteriorated by microorganisms. The content of the bactericide can be 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, etc.

[0034] Controlling the Fe3O4 nanoparticle content to 0.1%–1.5% has positive effects: Adding a certain percentage of Fe3O4 nanoparticles can improve the extreme pressure resistance and lubrication properties of the lubricant. Furthermore, the Fe3O4 nanoparticles can reduce surface roughness of the hot-rolled billet by removing surface protrusions. However, if the nanoparticle content is too high, they tend to agglomerate and precipitate, adversely affecting the stability of the lubricant. The Fe3O4 nanoparticle content can be varied, such as 0.1%, 0.3%, 0.5%, 0.8%, 1.2%, and 1.5%.

[0035] In some embodiments, the lubricating fluid is composed of the following components, measured by mass: 2% high-temperature grease; 0.8% Span 80; 0.05% diethanolamine oleate; 0.15% triethanolamine oleate; 0.03% bactericide; 0.5% Fe3O4 nanoparticles, and the balance is water.

[0036] In some embodiments, the operating temperature of the high-temperature grease is ≥1000°C.

[0037] The positive effect of controlling the operating temperature of high-temperature grease to ≥1000℃: During hot rolling of steel strip, the operating temperature is between 800℃ and 1250℃. If the operating temperature of high-temperature grease is lower than 1000℃, it will evaporate or burn off too quickly during the hot rolling process, losing its lubricating effect. The operating temperature of this high-temperature grease can be 1000℃, 1050℃, 1100℃, 1150℃, 1200℃, etc.

[0038] In some embodiments, the fungicide includes: 1,2-benzisothiazolin-3-one, 2-methylphenol-D8, dodecyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, dodecyldimethylbenzylammonium bromide, cyanoquaternary ammonium salt, polynitrogen heterocyclic quaternary ammonium salt, polyquaternary ammonium salt and diquaternary ammonium salt.

[0039] The biggest disadvantage of water-soluble lubricants is that they are easily deteriorated due to microbial contamination, which seriously affects their application in hot rolling processes. This disadvantage is overcome in the present application by adding a fungicide. The water-soluble lubricant obtained in the present application can be stored for a long time without deterioration.

[0040] In some embodiments, the Fe3O4 nanoparticles have a size of 10 nm to 50 nm.

[0041] Controlling the size of Fe3O4 nanoparticles to 10nm to 50nm has the positive effect of: the smaller the nanoparticle size, the better its dispersibility and stability in the lubricating fluid. The Fe3O4 nanoparticles can be 10nm, 15nm, 20nm, 30nm, 40nm, 50nm, etc.

[0042] In some embodiments, the amount and concentration of the water-soluble lubricating fluid used are related to the type of rolling mill, rolling process, rolling speed, type of rolled material, spraying pressure, nozzle diameter, nozzle arrangement, etc., and can be adjusted according to actual conditions.

[0043] In the second aspect, the present application provides a method for preparing a water-soluble lubricating fluid for hot rolling, see Figure 1 , the method is used to prepare the lubricating fluid according to any one embodiment of the first aspect, the method comprising:

[0044] S1. Add high-temperature grease to Span 80, then heat and stir to obtain component A;

[0045] S2, adding diethanolamine oleate, triethanolamine oleate and a fungicide to water, and then stirring to obtain component B;

[0046] S3. Add the component A, the component B and the Fe3O4 nanoparticle dispersion into water to obtain a water-soluble lubricating liquid for hot rolling.

[0047] Specifically, step S1 may be: adding the Span 80 and high-temperature grease into a reactor, heating to 70° C. to 120° C., and stirring until the grease is completely dissolved in the Span 80.

[0048] In some embodiments, the heating temperature is 70°C to 120°C.

[0049] Controlling the heating temperature to 70°C to 120°C has the following positive effects: This temperature range increases the dissolution rate of grease in the Span 80 and maintains an acceptable volatilization rate. Excessively high temperatures can lead to oxidation of the Span 80. Suitable heating temperatures include 70°C, 80°C, 90°C, 110°C, and 120°C.

[0050] In some embodiments, the mass ratio of Fe3O4 nanoparticles to water in the Fe3O4 nanoparticle dispersion is 1:(3-7). The mass ratio of Fe3O4 nanoparticles to water in the Fe3O4 nanoparticle dispersion can be 1:3, 1:4, 1:5, 1:6, 1:7, etc.

[0051] The present application will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present application only and are not intended to limit the scope of the present application. The experimental methods in the following examples where specific conditions are not specified are usually measured in accordance with national standards. If there are no corresponding national standards, then the methods are carried out in accordance with general international standards, conventional conditions, or according to the conditions recommended by the manufacturer.

[0052] The components and contents of the lubricating liquids in the examples and comparative examples after dilution at a ratio of 1:10 are shown in Table 1. The high-temperature lubricating grease used was FUCHS GLEITMO820.

[0053] Table 1 Compositions of lubricating fluids in various embodiments and comparative examples and their mass percentages (wt%)

[0054]

[0055] The lubricating fluids obtained in the examples and comparative examples were subjected to a four-ball friction test, and the friction coefficients obtained in the test are shown in Table 2.

[0056] Table 2 Friction coefficients of lubricating fluids in various embodiments and comparative examples

[0057]

[0058] As shown in Table 2, a comparison of Examples 1 to 3 shows that Example 3 has the best lubrication effect. Example 3 and Comparative Example 1 demonstrate that Fe3O4 nanoparticles can improve the lubrication properties of the lubricating fluid. Example 3, Comparative Examples 2, and Comparative Example 3 demonstrate that Span 80, diethanolamine oleate, and triethanolamine oleate have a synergistic emulsification effect. If the lubricating fluid contains only Span 80 or diethanolamine oleate and triethanolamine oleate, a stable solution cannot be formed. Example 3, Comparative Examples 4 and Comparative Examples 5 demonstrate that diethanolamine oleate and triethanolamine oleate synergistically improve grease dispersion. If the lubricating fluid contains only diethanolamine oleate or triethanolamine oleate, a yellow oil precipitates on the upper layer of the solution after heating and mixing, cooling to room temperature, and standing.

[0059] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. A water-soluble lubricating fluid for hot rolling, characterized in that: The lubricating fluid is composed of the following components by mass fraction: 1% to 10% high-temperature lubricating grease; 0.4% to 4% Span 80; 0.05% to 0.075% diethanolamine oleate; 0.1% to 0.2% triethanolamine oleate; 0.01% to 0.05% fungicide; 0.1% to 1.5% Fe3O4 nanoparticles; and the balance is water.

2. The lubricating fluid according to claim 1, characterized in that The lubricating fluid is composed of the following components by mass fraction: 2% high-temperature lubricating grease; 0.8% Span 80; 0.05% diethanolamine oleate; 0.15% triethanolamine oleate; 0.03% bactericide; 0.5% Fe3O4 nanoparticles; and the balance is water.

3. The lubricating fluid according to claim 1, characterized in that The operating temperature of the high-temperature grease is ≥1000°C.

4. The lubricating fluid according to claim 1, characterized in that The bactericide includes: one or more of 1,2-benzisothiazolin-3-one, 2-methylphenol-D8, dodecyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, dodecyldimethylbenzylammonium bromide, cyanoquaternary ammonium salt, polynitrogen heterocyclic quaternary ammonium salt, polyquaternary ammonium salt, and diquaternary ammonium salt.

5. The lubricating fluid according to claim 1, characterized in that The size of the Fe3O4 nanoparticles is 10nm~50nm.

6. A method for preparing a water-soluble lubricating fluid for hot rolling, characterized in that: The method is used to prepare the lubricating fluid according to any one of claims 1 to 5, and the method comprises: Add high-temperature grease to Span 80, then heat and stir to obtain component A; Add diethanolamine oleate, triethanolamine oleate and a fungicide into water, and then stir to obtain component B; The component A, the component B and the Fe3O4 nanoparticle dispersion are added into water to obtain a water-soluble lubricating liquid for hot rolling.

7. The method according to claim 6, characterized in that The heating temperature is 70°C to 120°C.

8. The method according to claim 6, characterized in that The mass ratio of Fe3O4 nanoparticles to water in the Fe3O4 nanoparticle dispersion is 1:(3-7).

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