An oil-in-water metalworking oil and a method for producing the same

Abstract

The application discloses an oil-in-water metal processing oil and a preparation method thereof. The oil-in-water metal processing oil comprises the following components: 4.9-8.0 wt% of oleophilic emulsifier, 3.8-6.3 wt% of base oil, 2.9-4.8 wt% of antirust agent, 75.2-80.1 wt% of tap water, 6.1-10.1 wt% of hydrophilic emulsifier and 0.1-0.4 wt% of preservative. The preparation method comprises the following steps: sequentially adding the oleophilic emulsifier, the base oil, the antirust agent, the tap water, the hydrophilic emulsifier and the preservative into a beaker, and then mechanically stirring at a rotating speed of 60-100 n / min for 10-20 min at room temperature to obtain the oil-in-water metal processing oil. The oil-in-water metal processing oil has superior cooling and lubricating performances. The amino acid surfactant is used as the antirust agent and the oleophilic emulsifier, so that the influence of water hardness on the stability of the metal processing oil is avoided. The fatty acid polyoxyethylene ester is used as the hydrophilic emulsifier, so that the hydrophilic emulsifier has strong hydrophilicity and excellent antirust performance, and the antirust agent and the hydrophilic emulsifier play a synergistic role, and the antirust performance is improved.

Description

Technical Field

[0001] This invention belongs to the field of metalworking oils, specifically relating to an oil-in-water type metalworking oil and its preparation method. Background Technology

[0002] During metal cutting, the intense friction between the cutting tool and the metal generates a large amount of heat, which can easily lead to thermal deformation of both the metal and the cutting tool. This results in reduced workpiece machining accuracy and tool wear and deformation. During processing, transfer, and storage, environmental factors such as air and moisture can also cause metal workpieces to rust and corrode. Currently, metalworking oils on the market are divided into two categories: water-soluble metalworking oils, which are made by diluting surfactants and lubricants with water; and water-insoluble metalworking oils, which are made primarily of mineral oil and used directly as the base solution. Water-soluble metalworking oils exhibit superior cooling performance but poor lubrication, leading to wear and deformation of metal workpieces and cutting tools. Water-insoluble metalworking oils exhibit superior lubrication performance but poor cooling performance, and the extensive use of mineral oil causes serious environmental pollution problems. Therefore, developing a metalworking oil that balances excellent cooling and lubrication performance has become a research hotspot. Summary of the Invention

[0003] Purpose of the invention: The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a water-in-oil type metalworking oil and its preparation method. The water-in-oil type metalworking oil prepared by the present invention contains both water and oil and has excellent cooling and lubrication properties.

[0004] Technical solution: A water-in-oil type metalworking fluid, comprising the following components,

[0005] Lipophilic emulsifier: 4.9–8.0 wt%;

[0006] Base oil: 3.8–6.3 wt%;

[0007] Rust inhibitor: 2.9–4.8 wt%;

[0008] Tap water: 75.2–80.1 wt%;

[0009] Hydrophilic emulsifier: 6.1–10.1 wt%;

[0010] Preservative: 0.1–0.4 wt%.

[0011] Furthermore, the lipophilic emulsifier is N-butyryl-N-butyldodecanoic acid alkyl ester, wherein the alkyl group refers to a straight-chain alkyl group of C4 to C12.

[0012] Furthermore, the rust inhibitor is N-propionyl-N-hexylhexadecanoic acid alkyl ester, wherein the alkyl group refers to a straight-chain alkyl group of C4 to C12.

[0013] Furthermore, the hydrophilic emulsifier is a fatty acid polyoxyethylene ester.

[0014] Furthermore, the hydrophilic emulsifier is one of polyoxyethylene laurate, polyoxyethylene oleate, or polyoxyethylene rosinate.

[0015] Furthermore, the base oil is 32. # Engine oil.

[0016] Furthermore, the preservative is dodecyl dimethyl benzyl ammonium chloride.

[0017] The present invention also provides a method for preparing an oil-in-water metalworking oil, wherein an oil-loving emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier and corrosion inhibitor are added sequentially to a beaker and mechanically stirred at a speed of 60-100 rpm for 10-20 minutes at room temperature to obtain an oil-in-water metalworking oil.

[0018] Beneficial effects:

[0019] 1) This invention innovatively uses amino acid surfactants as rust inhibitors and lipophilic emulsifiers. Because amino acid surfactants do not contain amines and sodium ions in their structure, they will not form insoluble salts with magnesium and calcium ions in tap water or heavy metal ions from machining operations, thus exhibiting superior stability.

[0020] It replaces the amine soap and sodium soap currently added to metalworking oils on the market, thus avoiding the impact of water hardness on the stability of metalworking oils, and therefore there is no need to add water softener.

[0021] 2) Fatty acid polyoxyethylene esters not only have carboxyl groups but also ester groups in their structure, so they are highly hydrophilic. This invention uses fatty acid polyoxyethylene esters as hydrophilic emulsifiers, which not only have strong hydrophilicity but also have excellent rust prevention properties. They work synergistically with the rust inhibitor N-propionyl-N-hexyl hexadecyl alkyl ester, which is beneficial to improving the rust prevention properties of metal processing oils.

[0022] 3) The base oil usage is low, and the amino acid surfactants have good biodegradability, making the waste liquid generated after use easy to treat and causing no environmental pollution problems;

[0023] 3) The metalworking oil prepared has a high water content and is an oil-in-water type. It also has excellent cooling and lubrication properties. It is easy to operate. Just add the raw materials in sequence and start stirring. The operation time is short, no heating is required, and energy consumption is low. Detailed Implementation

[0024] The technical solution of the present invention will be described in detail below through specific embodiments, but the scope of protection of the present invention is not limited to the embodiments described.

[0025] In this embodiment of the invention, the lipophilic emulsifier N-butyroyl-N-butyldodecanoic acid alkyl ester, wherein the alkyl group refers to a straight-chain alkyl group of C4 to C12, is prepared by self-processing according to an amino acid surfactant and its preparation method in patent ZL 202310477024.5. The rust inhibitor N-propionyl-N-hexylhexadecanoic acid alkyl ester is prepared by a catalytic dehydrochlorination reaction of α-chlorohexadecanoic acid alkyl ester and N-hexylpropionamide. Specifically, α-chlorohexadecanoic acid alkyl ester and N-hexylpropionamide are added to a reaction vessel at a molar ratio of 1:1.2, and a nano-HZSM-5 molecular sieve catalyst is added. The amount of catalyst is 0.5% of the total mass of α-chlorohexadecanoic acid alkyl ester and N-hexylpropionamide. The reaction is carried out at 60-80°C for 2-5 hours. After the reaction, the catalyst is removed by filtration, the filtrate is allowed to stand and separate into layers, and the lower layer is taken out to obtain the amino acid surfactant N-propionyl-N-hexylhexadecanoic acid alkyl ester. The remaining raw materials—base oil, hydrophilic emulsifier, and preservative—are all commercially available.

[0026] Example 1

[0027] Add 3.25g of the lipophilic emulsifier N-butyroyl-N-butyl dodecyl ester and 2.7g of base oil 32 # Machine oil, 2.05g of rust inhibitor N-propionyl-N-hexyl palmitate butyl ester, 37.6g of tap water, 4.3g of hydrophilic emulsifier polyoxyethylene laurate, and 0.1g of preservative dodecyl dimethyl benzyl ammonium chloride were sequentially added to a beaker. The mixture was then mechanically stirred at 60 rpm for 10 minutes at room temperature to obtain the metalworking oil. The mass percentages of the hydrophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative were 6.5%, 5.4%, 4.1%, 75.2%, 8.6%, and 0.2%, respectively.

[0028] Example 2

[0029] Add 2.45g of the lipophilic emulsifier N-butyroyl-N-butyldodecyl octyl ester and 2.4g of base oil 32 #Engine oil, 1.7g of rust inhibitor N-propionyl-N-hexyl palmitate lauryl ester, 40.05g of tap water, 3.25g of hydrophilic emulsifier rosin acid polyoxyethylene ester, and 0.15g of preservative dodecyl dimethyl benzyl ammonium chloride were sequentially added to a beaker. The mixture was then mechanically stirred at 80 rpm for 20 minutes at room temperature to obtain the metalworking oil. The mass percentages of the hydrophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative were 4.9%, 4.8%, 3.4%, 80.1%, 6.5%, and 0.3%, respectively.

[0030] Example 3

[0031] Add 4.0g of the lipophilic emulsifier N-butyroyl-N-butyldodecyl lauryl ester and 2.05g of base oil 32 # Machine oil, 1.55g of rust inhibitor N-propionyl-N-hexylhexadecanoate, 38.15g of tap water, 4.05g of hydrophilic emulsifier polyoxyethylene oleate, and 0.2g of preservative dodecyl dimethyl benzyl ammonium chloride were sequentially added to a beaker. The mixture was then mechanically stirred at 100 rpm for 15 minutes at room temperature to obtain the metalworking oil. The mass percentages of the hydrophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative were 8.0%, 4.1%, 3.1%, 76.3%, 8.1%, and 0.4%, respectively.

[0032] Example 4

[0033] Add 3.75g of the lipophilic emulsifier N-butyroyl-N-butyldodecyl hexyl ester and 2.8g of base oil 32 # Engine oil, 1.9g of rust inhibitor N-propionyl-N-hexylhexyl palmitate, 38.4g of tap water, 3.05g of hydrophilic emulsifier polyoxyethylene laurate, and 0.1g of preservative dodecyl dimethyl benzyl ammonium chloride were sequentially added to a beaker. The mixture was then mechanically stirred at 70 rpm for 10 minutes at room temperature to obtain the metalworking oil. The mass percentages of the hydrophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative were 7.5%, 5.6%, 3.8%, 76.8%, 6.1%, and 0.2%, respectively.

[0034] Example 5

[0035] Add 2.85g of the lipophilic emulsifier N-butyroyl-N-butyldodecyl ester and 2.0g of base oil 32 #Engine oil, 1.7g of rust inhibitor N-propionyl-N-hexyl palmitate octyl ester, 38.3g of tap water, 5.05g of hydrophilic emulsifier polyoxyethylene oleate, and 0.1g of preservative dodecyl dimethyl benzyl ammonium chloride were sequentially added to a beaker. The mixture was then mechanically stirred at 60 rpm for 20 minutes at room temperature to obtain the metalworking oil. The mass percentages of the hydrophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative were 5.7%, 4.0%, 3.4%, 76.6%, 10.1%, and 0.2%, respectively.

[0036] Comparative Example

[0037] According to the mass percentage of each raw material in Example 2, the mass percentages of lipophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and preservative are 4.9%, 4.8%, 3.4%, 80.1%, 6.5%, and 0.3%, respectively. 2.45g of lipophilic emulsifier N-butyroyl-N-butyl dodecyl octyl ester and 2.4g of base oil 32... # After adding engine oil, 1.7g of rust inhibitor N-propionyl-N-hexyl palmitate, 40.05g of tap water, 3.25g of hydrophilic emulsifier methyl allyl polyoxyethylene ether, and 0.15g of preservative dodecyl dimethyl benzyl ammonium chloride to a beaker in sequence, the mixture is mechanically stirred at 80 rpm for 20 minutes at room temperature to obtain the metalworking oil.

[0038] The metalworking oils obtained in the above examples and comparative examples were subjected to performance tests: Stability test method: 100 mL of metalworking oil was dropped into a 100 mL burette using a pipette, and after 24 hours, the layering phenomenon was observed. If layering occurred, the percentage of the upper oil layer's volume in 100 mL was calculated; the smaller this value, the better the stability. Rust prevention performance test method: A cast iron sheet was completely immersed in the metalworking oil, then removed and placed in a 25°C constant temperature chamber. The time required for rust spots to appear was observed; the longer the time, the better the rust prevention performance. The performance test results are shown in the table below:

[0039] Example 1 0 182 Example 2 0 185 Example 3 0 178 Example 4 0 183 Example 5 0 180 Comparative Example 10.3 91

[0040] The performance test results show that, in the comparative example, after replacing the hydrophilic emulsifier rosin acid polyoxyethylene ester in Example 2 with methyl allyl polyoxyethylene ether, the stability and rust prevention performance of the prepared metalworking oil were significantly reduced. The main reason is that the rosin acid polyoxyethylene ester in Example 2 has not only carboxyl groups but also ester groups in its structure, so it has strong hydrophilicity. In contrast, the methyl allyl polyoxyethylene ether in the comparative example only has ether groups in its structure, so it has poor hydrophilicity. As a result, the prepared metalworking oil is prone to oil-water separation.

[0041] As described above, although the invention has been shown and described with reference to specific preferred embodiments, it should not be construed as limiting the invention itself. Various changes in form and detail may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. A water-in-oil type metalworking fluid, characterized in that, It consists of the following components: Lipophilic emulsifier: 4.9–8.0 wt%; Base oil: 3.8–6.3 wt%; Rust inhibitor: 2.9–4.8 wt%; Tap water: 75.2–80.1 wt%; Hydrophilic emulsifier: 6.1–10.1 wt%; Preservative: 0.1–0.4 wt%; The lipophilic emulsifier is N-butyroyl-N-butyl dodecyl ester, wherein the alkyl group refers to a straight-chain alkyl group of C4 to C12; the rust inhibitor is N-propionyl-N-hexyl hexadecyl ester, wherein the alkyl group refers to a straight-chain alkyl group of C4 to C12; the hydrophilic emulsifier is one of polyoxyethylene laurate, polyoxyethylene oleate, or polyoxyethylene rosinate; and the corrosion inhibitor is dodecyl dimethyl benzyl ammonium chloride.

2. The water-in-oil type metalworking fluid according to claim 1, characterized in that, The base oil is 32. # Engine oil.

3. The method for preparing water-in-oil type metalworking fluid according to claim 1, characterized in that, After adding the oleophilic emulsifier, base oil, rust inhibitor, tap water, hydrophilic emulsifier, and corrosion inhibitor to a beaker in sequence, mechanically stir at a speed of 60-100 rpm for 10-20 minutes at room temperature to obtain the water-in-oil type metalworking oil.