Environment-friendly long-life semi-synthetic cutting fluid and preparation method thereof

Abstract

The invention relates to the technical field of cutting fluid, in particular to environment-friendly long-service-life semi-synthetic cutting fluid and a preparation method of the environment-friendly long-service-life semi-synthetic cutting fluid. 30 to 50 parts of mineral oil; 5-10 parts of a friction modifier; 3-5 parts of an antirust agent; 10 to 20 parts of alcohol amine; 5 to 10 parts of a surfactant; 0.1 to 1 part of a bacteriostatic agent; organic matters adopted by the cutting fluid are isomerized and branched, so that the physical performance and stability of the cutting fluid are remarkably improved, the organic matters adopted by the cutting fluid are macromolecular structures and are not easy to hydrolyze, the stability of the cutting fluid is improved, and the organic matters adopted by the cutting fluid do not contain a large amount of strong-basicity and formaldehyde-containing bactericides; in addition, the bacteriostatic agent is added into the cutting fluid, so that the cutting fluid has the effect of inhibiting microorganisms and is not easy to stink, the safety and the stability of the cutting fluid are further improved, and the service life of the cutting fluid is prolonged.

Description

Technical Field

[0001] The invention relates to the technical field of cutting fluids, and in particular to an environmentally friendly, long-life semi-synthetic cutting fluid and a preparation method thereof. Background Art

[0002] Cutting fluid is a liquid used for rust prevention, lubrication, cooling and cleaning during the process of cutting metal workpieces by machine tools. It can ensure the accuracy and surface finish of the workpiece and extend the service life of the tool. Cutting fluid generally refers to water-based products. According to the source of raw materials, cutting fluid can be divided into two categories: fully synthetic and semi-synthetic. Fully synthetic means that all the raw materials used are synthetic, and semi-synthetic means that the raw materials used are partially synthetic and partially natural, taken from plants or minerals.

[0003] Existing cutting fluids have a short lifespan and poor stability, and tend to stink after long-term use, so they need to be replaced frequently, which increases the cost of cutting fluid investment for factories. Since more waste fluid is often generated, environmental pressure is further increased.

[0004] For example, the invention patent with patent application number 201610656237.4 discloses a long-life low-foam microemulsion for aluminum alloy cutting. The patented product has good lubricity, but its lubricating additives are synthesized with oleic acid and ricinoleic acid. The structure of such reactants determines that it will not have very good microbial stability and is easily degraded by microorganisms. In addition, it also contains phosphate esters that are very unfriendly to the environment, which greatly increases the speed of microbial reproduction. It still uses a large amount of alkaline substances and formaldehyde releasers to inhibit bacteria, and a large amount of alkaline alcohol amines such as monoethanolamine, isopropanolamine and triethanolamine are not only irritating to the human body, but also severely corrosive to non-ferrous metals, and formaldehyde is a well-known strong carcinogen.

[0005] This solution is based on the increasingly stringent environmental laws and regulations and the improvement of people's environmental awareness, and provides a cutting fluid with long life, low odor and no harmful ingredients to the human body. Summary of the invention

[0006] The purpose of the present invention is to provide an environmentally friendly, long-life semi-synthetic cutting fluid and a preparation method thereof, which solves the problems of the service life and safety of the cutting fluid.

[0007] To achieve the above object, the present invention provides the following technical solution: an environmentally friendly long-life semi-synthetic cutting fluid, which is composed of the following components by weight:

[0008] Water, 5-53 parts;

[0009] Mineral oil, 30-50 parts;

[0010] Friction modifier, 5-10 parts;

[0011] Rust inhibitor, 3 to 5 parts;

[0012] Alkylamine, 10-20 parts;

[0013] Surfactant, 5-10 parts;

[0014] Antibacterial agent, 0.1 to 1 part.

[0015] The friction modifier is one or at least two of polyisobutylene succinic acid, isomerized stearic acid and polyester, all of which have branched structures.

[0016] The rust inhibitor is one or two of tricarboxylic acid and amide.

[0017] The alcohol amine is one or at least two of aminomethyl propanol, triisopropanolamine and dibutylethanolamine.

[0018] The surfactant is one or both of branched alkyl alcohol polyoxyethylene ether and alkylamine polyoxyethylene ether.

[0019] The antibacterial agent is one or two of lactic acid and iodopropynyl n-butylamine formate.

[0020] A method for preparing an environmentally friendly, long-life semi-synthetic cutting fluid comprises the following steps:

[0021] Step S1: preparing a mixing container, weighing the above-mentioned parts by weight of mineral oil, friction modifier, rust inhibitor, alcohol amine, surfactant and antibacterial agent, and adding the parts by weight of mineral oil into the mixing container;

[0022] Step S2: gradually adding the friction modifier in the weight portion to the mineral oil at a stirrer speed of 140-160 rpm, and stirring for 8-12 minutes until the mineral oil and the friction modifier are fully mixed;

[0023] Step S3: adding the weight portion of surfactant and stirring for 8-12 minutes to obtain a mixture containing the friction modifier and the surfactant;

[0024] Step S4: adding the weight portion of the rust inhibitor to the mixture and stirring evenly;

[0025] Step S5: adding the weight portion of alcoholamine to the mixture and stirring evenly to obtain a semi-finished product;

[0026] Step S6: slowly add the above-mentioned water in parts by weight to the semi-finished product until the pH value of the semi-finished product is 10-11, and continuously stir until the semi-finished product is evenly mixed to form a transparent and uniform liquid to obtain a finished cutting fluid.

[0027] The mineral oil is prepared by refining crude oil twice, and hydrogenation is performed during the second refining.

[0028] Furthermore, in step S2, the speed of the agitator is 140-160 rpm; in step S3, the speed of the agitator is 140-160 rpm; in step S4, the speed of the agitator is 240-260 rpm; in step S5, the speed of the agitator is 240-260 rpm; in step S6, the speed of the agitator is 390-410 rpm.

[0029] Technical effects and advantages of the present invention:

[0030] 1. In this scheme, the organic matter used in the cutting fluid has isomeric branching, which significantly improves the physical properties and stability of the cutting fluid. The organic matter used in the cutting fluid has a large molecular structure and is not easy to hydrolyze, which improves the stability of the cutting fluid. The organic matter used in the cutting fluid does not contain a large amount of strong alkalinity and formaldehyde-containing fungicides, and will not harm or irritate the human body. In addition, antibacterial agents are added to the cutting fluid, which has the effect of inhibiting microorganisms and is not easy to become smelly, further improving the safety and stability of the cutting fluid and extending the service life of the cutting fluid.

[0031] 2. In this solution, no alloys such as aluminum, copper, and zinc that are prone to discoloration are used in the cutting fluid, so the workpiece will not be discolored. DETAILED DESCRIPTION

[0032] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The existing technology is to use a large amount of strong alkaline substances and formaldehyde-releasing fungicides to achieve long-life cutting fluids. Strong alkaline substances can irritate the skin, causing redness, itching and cracking of the skin, which leads to a high turnover rate of factory operators; excessive alkalinity can cause non-ferrous metals, such as aluminum, copper, zinc and other alloys, to change color easily, and the defective rate of workpieces remains high. Formaldehyde is well known and is listed as a national first-level carcinogen. The use of such fungicides will have a profound adverse effect on the human body.

[0034] Example 1

[0035] This embodiment provides an environmentally friendly, long-life semi-synthetic cutting fluid.

[0036] The components are as follows by weight:

[0037] water, 47 parts;

[0038] Mineral oil, 30 parts;

[0039] Friction modifier, 5 parts;

[0040] Rust inhibitor, 3 parts;

[0041] Alkanolamine, 10 parts;

[0042] Surfactant, 5 parts;

[0043] Antibacterial agent, 0.1 part.

[0044] Example 2

[0045] This embodiment provides an environmentally friendly, long-life semi-synthetic cutting fluid.

[0046] The components are as follows by weight:

[0047] Water, 26 parts;

[0048] Mineral oil, 40 parts;

[0049] Friction modifier, 7 parts;

[0050] Rust inhibitor, 4 parts;

[0051] Alkanolamine, 15 parts;

[0052] Surfactant, 7 parts;

[0053] Antibacterial agent, 0.6 parts.

[0054] Example 3

[0055] This embodiment provides an environmentally friendly, long-life semi-synthetic cutting fluid.

[0056] The components are as follows by weight:

[0057] Water, 4 parts;

[0058] Mineral oil, 50 parts;

[0059] Friction modifier, 10 parts;

[0060] Rust inhibitor, 5 parts;

[0061] Alkylamine, 20 parts;

[0062] Surfactant, 10 parts;

[0063] Antibacterial agent, 1 part.

[0064] In the above embodiments 1 to 3, the friction modifiers are selected from polyisobutylene succinic acid, isomerized stearic acid and polyester, all of which have branched structures; the rust inhibitors are selected from tricarboxylic acids and amides; the alcoholamines are selected from aminomethyl propanol, triisopropanolamine and dibutylethanolamine; the surfactants are selected from branched alkyl alcohol polyoxyethylene ethers and alkylamine polyoxyethylene ethers; and the antibacterial agents are selected from lactic acid and iodopropynyl n-butylamine formate.

[0065] Comparative Example 1

[0066] In this comparative example, compared with Example 1, the friction modifier in the cutting fluid is replaced by polyisobutylene succinic acid, isomerized stearic acid and polyester with no branched structure.

[0067] Comparative Example 2

[0068] In this comparative example, compared with Example 2, the alcohol amine in the cutting fluid is removed.

[0069] Comparative Example 3

[0070] In this comparative example, compared with Example 3, the antibacterial agent in the cutting fluid is replaced by a strong base and a weak acid salt.

[0071] Experimental example

[0072] In this experiment, 10 to 50 people were randomly selected as observers. 10 g of the cutting fluid respectively prepared in the above-mentioned Examples 1 to 3 and Comparative Examples 1 to 3 were taken, and a metal block was placed in the cutting fluid. The cutting fluid was placed at room temperature for 7 days, 14 days and 28 days, and the observers observed and recorded the odor change, deterioration degree and color change of the metal block of the cutting fluid. The metal block was taken out of the cutting fluid after 1 day. Specifically, the number of observers selected in this experiment was 10, and the deterioration degree of the cutting fluid was determined by the pH method. The experimental data are recorded in the following Tables 1 to 13.

[0073] Table 1 Odor change of cutting fluid (Example 1)

[0074] Observer 24h 7d 14d 28d 1 none none none slight 2 none none slight medium 3 none none none slight 4 none none none none 5 none none slight slight 6 none none none none 7 none none none none 8 none none none slight 9 none slight slight medium 10 none none slight slight

[0075] Table 2 Odor change of cutting fluid (Example 2)

[0076]

[0077]

[0078] Table 3 Odor change of cutting fluid (Example 3)

[0079] Observer 24h 7d 14d 28d 1 none none none slight 2 none none slight medium 3 none none none slight 4 none none none none 5 none none slight slight 6 none none none none 7 none none none none 8 none none none slight 9 none none slight medium 10 none none slight slight

[0080] Table 4 Odor change of cutting fluid (Comparative Example 1)

[0081] Observer 24h 7d 14d 28d 1 none slight serious serious 2 slight medium serious serious 3 slight slight medium serious 4 none slight medium serious 5 slight slight medium serious 6 slight slight medium serious 7 slight medium serious serious 8 slight medium serious serious 9 slight medium medium serious 10 none slight medium serious

[0082] Table 5 Odor change of cutting fluid (Comparative Example 2)

[0083]

[0084]

[0085] Table 6 Odor change of cutting fluid (Comparative Example 3)

[0086] Observer 24h 7d 14d 28d 1 none slight medium serious 2 slight medium medium serious 3 slight slight medium serious 4 none slight medium serious 5 slight slight medium serious 6 slight slight medium serious 7 slight slight medium serious 8 none slight serious serious 9 none slight medium serious 10 none slight medium serious

[0087] Table 7 Deterioration degree of cutting fluid (pH value method)

[0088] Observer 24h 7d 14d 28d Example 1 11.0 10.8 9.6 9.0 Example 2 10.5 10.5 9.0 8.2 Example 3 10.9 10.7 9.1 8.5 Comparative Example 1 10.2 9.3 7.2 7.1 Comparative Example 2 10.0 9.5 7.9 7.6 Comparative Example 3 10.6 9.2 7.6 7.2

[0089] Table 8 Color change degree of metal block (Example 1)

[0090] Observer 24h 7d 14d 28d 1 none none none none 2 none none none none 3 none none none slight 4 none none none none 5 none none slight slight 6 none none none none 7 none none slight slight 8 none none none none 9 none none none none 10 none none none slight

[0091] Table 9 Color change degree of metal block (Example 2)

[0092]

[0093]

[0094] Table 10 Color change degree of metal block (Example 3)

[0095] Observer 24h 7d 14d 28d 1 none none none slight 2 none none slight medium 3 none none none slight 4 none none slight medium 5 none none none slight 6 none none none none 7 none none slight slight 8 none none none none 9 none none none none 10 none none slight medium

[0096] Table 11 Color change degree of metal block (Comparative Example 1)

[0097] Observer 24h 7d 14d 28d 1 slight slight medium serious 2 slight slight medium serious 3 slight slight medium serious 4 none slight medium serious 5 slight medium medium serious 6 slight medium medium serious 7 slight medium medium serious 8 none slight serious serious 9 slight slight medium serious 10 slight medium medium serious

[0098] Table 12 Color change degree of metal block (Comparative Example 2)

[0099]

[0100]

[0101] Table 13 Color change degree of metal block (Comparative Example 3)

[0102] Observer 24h 7d 14d 28d 1 slight slight medium serious 2 none slight medium serious 3 none slight medium serious 4 slight slight medium serious 5 slight slight medium serious 6 slight medium serious serious 7 slight medium serious serious 8 slight medium medium serious 9 none slight medium serious 10 slight medium serious serious

[0103] It can be seen from Tables 1-6 that the odor of the cutting fluid prepared by the present method changes slowly, while the odor of the cutting fluid used in the comparative example changes significantly. In about two weeks at room temperature, the cutting fluid changes from having no obvious odor to seriously smelling. It can be seen from Table 7 that the cutting fluids of Examples 1-3 and Comparative Examples 1-3 have deteriorated significantly and cannot maintain a stable pH value for a long time. Therefore, the cutting fluid of the present invention achieves a long life without a large amount of strong alkalinity and formaldehyde-containing fungicides, and the organic matter used in the cutting fluid has isomeric branching, thereby significantly improving the physical properties and stability of the cutting fluid. The organic matter used in the cutting fluid has a macromolecular structure and is not easily hydrolyzed, thereby improving the stability of the cutting fluid. The organic matter used in the cutting fluid does not contain a large amount of strong alkalinity and formaldehyde-containing fungicides, and will not harm or irritate the human body. In addition, an antibacterial agent is added to the cutting fluid, which has the effect of inhibiting microorganisms and is not easy to smell, further improving the safety and stability of the cutting fluid and extending the service life of the cutting fluid.

[0104] Furthermore, it can be seen from Tables 8-13 that for the cutting fluids of Examples 1-3, at 14d and 28d, most observers only observed slight color changes, while for the cutting fluids of Comparative Examples 1-3, at 14d and 28d, most observers could observe severe discoloration of the metal blocks. Therefore, the cutting fluids do not use alloys that are prone to discoloration, such as aluminum, copper, and zinc, and therefore long-term use will not cause significant discoloration of the workpiece.

[0105] Example 4

[0106] The present invention also provides a method for preparing an environmentally friendly, long-life semi-synthetic cutting fluid, comprising the following steps:

[0107] Step S1: preparing a mixing container, weighing the above-mentioned parts by weight of mineral oil, friction modifier, rust inhibitor, alcohol amine, surfactant and antibacterial agent, and adding the parts by weight of mineral oil into the mixing container;

[0108] Step S2: gradually adding the friction modifier by weight into the mineral oil with a stirrer at a rotation speed of 150 rpm, and stirring for 10 minutes until the mineral oil and the friction modifier are fully mixed;

[0109] Step S3: adding the weight portion of surfactant again and stirring at 150 rpm to obtain a mixture containing the friction modifier and the surfactant;

[0110] Step S4: adding the weight portion of the rust inhibitor to the mixture and stirring evenly;

[0111] Step S5: adding the weight portion of alcoholamine to the mixture and stirring evenly to obtain a semi-finished product;

[0112] Step S6: slowly add the above-mentioned weight portions of water to the semi-finished product until the pH value of the semi-finished product reaches 10.5, and continuously stir until the semi-finished product is evenly mixed to form a transparent and uniform liquid, thereby obtaining a finished cutting fluid.

[0113] The mineral oil is produced by refining crude oil twice, and hydrogenation is performed during the second refining.

[0114] In the above-mentioned embodiment 4, in step S2, the rotation speed of the agitator is 150 rpm; in step S3, the rotation speed of the agitator is 150 rpm; in step S4, the rotation speed of the agitator is 250 rpm; in step S5, the rotation speed of the agitator is 250 rpm; in step S6, the rotation speed of the agitator is 400 rpm.

[0115] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An environmentally friendly, long-life semi-synthetic cutting fluid, characterized in that: The components are as follows by weight: Water, 5-53 parts; Mineral oil, 30-50 parts; Friction modifier, 5-10 parts; Rust inhibitor, 3-5 parts; Alkylamine, 10-20 parts; Surfactant, 5-10 parts; Antibacterial agent, 0.1 to 1 part.

2. The environmentally friendly, long-life semi-synthetic cutting fluid according to claim 1, characterized in that: The friction modifier is any one of polyisobutylene succinic acid, isomerized stearic acid and polyester, all of which have branched structures, or a combination of at least two of them.

3. The environmentally friendly, long-life semi-synthetic cutting fluid according to claim 1, characterized in that: The rust inhibitor is any one of tricarboxylic acid and amide or a combination of two thereof.

4. The environmentally friendly, long-life semi-synthetic cutting fluid according to claim 1, characterized in that: The alcohol amine is any one of aminomethyl propanol, triisopropanolamine, and dibutylethanolamine, or a combination of at least two thereof.

5. The environmentally friendly, long-life semi-synthetic cutting fluid according to claim 1, characterized in that: The surfactant is any one of branched alkyl alcohol polyoxyethylene ether and alkylamine polyoxyethylene ether, or a combination of both.

6. An environmentally friendly, long-life semi-synthetic cutting fluid as claimed in any one of claims 1 to 5, characterized in that: The antibacterial agent is one or two of lactic acid and iodopropynyl n-butylamine formate.

7. A method for preparing an environmentally friendly, long-life semi-synthetic cutting fluid, used for preparing the environmentally friendly, long-life semi-synthetic cutting fluid as claimed in claim 1, characterized in that: The following steps are involved: Step S1: preparing a mixing container, weighing the above-mentioned parts by weight of mineral oil, friction modifier, rust inhibitor, alcohol amine, surfactant and antibacterial agent, and adding the parts by weight of mineral oil into the mixing container; Step S2: gradually adding the friction modifier in the weight portion to the mineral oil at a stirrer speed of 140-160 rpm, and stirring for 8-12 minutes until the mineral oil and the friction modifier are fully mixed; Step S3: adding the weight portion of surfactant and stirring for 8-12 minutes to obtain a mixture containing the friction modifier and the surfactant; Step S4: adding the weight portion of the rust inhibitor to the mixture and stirring evenly; Step S5: adding the weight portion of alcoholamine to the mixture and stirring evenly to obtain a semi-finished product; Step S6: slowly add the above-mentioned water in parts by weight to the semi-finished product until the pH value of the semi-finished product is 10-11, and continuously stir until the semi-finished product is evenly mixed to form a transparent and uniform liquid to obtain a finished cutting fluid.

8. The method for preparing an environmentally friendly and long-life semi-synthetic cutting fluid according to claim 7, characterized in that: The mineral oil is produced by refining crude oil twice, and hydrogenation is performed during the second refining.

9. The method for preparing an environmentally friendly and long-life semi-synthetic cutting fluid according to claim 7, characterized in that: In step S2, the rotation speed of the agitator is 140-160 rpm; in step S3, the rotation speed of the agitator is 140-160 rpm; in step S4, the rotation speed of the agitator is 240-260 rpm; in step S5, the rotation speed of the agitator is 240-260 rpm; in step S6, the rotation speed of the agitator is 390-410 rpm.

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