RU2790826C1 - Lubricant-coolant concentrate for magnetic-abrasive machining of metals - Google Patents

Abstract

FIELD: coolant concentrates.

SUBSTANCE: invention relates to coolant concentrates that can be used in the form of aqueous solutions in the engineering industry in the MAO operations of non-ferrous metals, steels and their alloys. The coolant concentrate consists of components, wt %: triethanolamine soap of synthetic fatty acids C₇-C₉ 30.0-50.0, oleic acid 10.0-15.0, sodium sulfoethoxylate 5.0-10, 0, potassium hydroxide 2.0, sodium nitrite 2.0, industrial oil 2.0-4.0, water the rest.

EFFECT: increasing productivity in magnetic-abrasive machining and reducing the roughness of machined surfaces.

1 cl, 3 ex, 3 tbl

Description

Technical field

Metalworking processes are characterized by an exceptional variety of conditions due to the extensive range of processed and tool materials, the specifics of specific operations, the type and scale of production. One of the ways to increase the productivity of machining and ensure the desired quality of the machined surface is the correct choice and use of coolant. Solving the problems of increasing the efficiency of the use of coolants is implemented by selecting and changing their compositions, which allows for multilateral changes in the parameters of the functioning of metal processing systems.

The invention relates to coolant concentrates that can be used in the form of aqueous solutions in the engineering industry in the MAO operations of non-ferrous metals, steels and their alloys.

State of the art

Known concentrate technological coolant for finishing diamond-abrasive processing of metals, containing, wt.%: triethanolamine soap of fatty acids fraction C ₆ -C ₂₀ 25.0-30.0, diethylene glycol 20.0-30.0, sodium nitrite 0.4 -0.6 and water [1]. The disadvantage of the known coolant concentrate is the instability of its performance properties, namely, during operation, there is a decrease in the cutting ability of the tool.

Known concentrate technological coolant for finishing abrasive processing of metals, containing, wt.%: triethanolamine 10.0-20.0, methyl sulfate 1.0-3.0, ethoxylated monolacylphenols based on propylene trimers 20.0-30.0 and water [ 2]. The disadvantage of the known coolant concentrate is the lack of performance of the cutting tool when it is used in the finishing operations.

Known concentrate technological coolant for machining metals, containing, wt.%: triethanolamine 0.8-2.0, triethanolamine soap of higher fatty acids 9.0-14.0, triethanolamine soap of synthetic fatty acids fraction C ₇ -C ₉ or C ₁₀ -C ₁₃ 1.5-3.5, polyoxyethylated primary fatty alcohols of fraction C ₁₀ -C ₁₃ or C ₁₂ -C ₁₄ or C ₁₀ -C ₁₈ 4.0-8.0, tall oil distillation pitch 4.0- 8.0, zinc dialkyldithiophosphate 1.0-4.0, extract of selective purification of petroleum oils 10.0-20.0 and the rest is mineral oil [3]. A disadvantage of the known coolant concentrate is the presence of glycol derivatives in its composition, which during operation oxidize the coolant with the formation of acidic corrosion-resistant agents, which reduces the pH and the degree of permissible pollution.

Closest to the claimed technical solution of the invention is a coolant concentrate used for machining metals by cutting, containing, wt.%: triethanolamine 4.0-10.0, triethanolamine fatty acid soap 8.0-20.0, polyethylene glycol monoalkyl ethers based on primary fatty alcohols 2.0-6.0, calcium and/or sodium soap of castor oil acids 2.0-12.0, mineral oil 1.0-7.0 and water [4]. The disadvantage of the prototype is that it is not universal, contains a low percentage of oil (more than 50% consists of water).

The problem solved by the invention is the development of the composition of the coolant concentrate for MAO, which meets the requirements for the quality indicators of the coolant used for the finishing operations of metalworking of steels and alloys, and also contributes to the expansion of the range of produced coolants.

The essence of the invention

The task is achieved by the fact that the coolant concentrate, which can be used in the form of an aqueous solution in the engineering industry for MAO operations of non-ferrous metals, steels and their alloys, includes triethanolamine soap of synthetic C7-C9 fatty acids, oleic acid, potassium hydroxide, sodium nitrite, industrial oil and water, which additionally contains sodium sulfoethoxylate, wt.%:

triethanolamine soap synthetic fatty acids 30.0-50.0 C ₇ -C ₉ oleic acid 10.0-15.0 sodium sulfoethoxylate 5.0-10.0 potassium hydroxide 2.0 sodium nitrite 2.0 industrial oil 2.0-4.0 water rest

The technical result achieved by the claimed invention is to simultaneously increase productivity and reduce the roughness of the treated surfaces during MAO by improving the performance characteristics of the claimed concentrate.

The composition of the coolant concentrate uses the following components:

- triethanolamine soap of the C ₇ -C ₉ fraction, produced according to TU 2423-061-05807977-2002 (leads to an improvement in wetting, washing and emulsifying properties, and also contributes to the formation of a stable emulsion and does not delaminate during storage for a long time);

- oleic acid, produced in accordance with GOST 7580-91 (leads to an improvement in the emulsification of the oil and lubricating properties);

- sodium sulfoethoxylate, produced according to TU 2481-017-71150986-2011 (it is a surfactant of the proposed coolant concentrate and acts as a washing detergent);

- potassium hydroxide, produced in accordance with GOST 24363-80 (in the proposed concentrate coolant is used as a lubricant);

- sodium nitrite, produced in accordance with GOST 19906-74 (used to isolate hardness salts and prevent their reaction with soap, which affects the performance of the process as a whole);

- industrial oil I-8A, produced in accordance with GOST 20799-88 (used for the operation of chemical or electrochemical degreasing of parts during processing).

The proposed ratio of components makes it possible to obtain a material with high performance properties and the lowest costs.

The proposed coolant concentrate is obtained by simple mechanical mixing of its components with water by continuous stirring for 45-60 minutes at a temperature of (50-70)°C. For magnetic-abrasive machining of metals, a 3% solution of coolant concentrate in water is used.

The inventive coolant concentrates are yellow-brown oily liquids that are easily diluted with both technical and tap water at a temperature of (10-20) ° C to form translucent milky solutions.

The following proposed compositions of coolant concentrates have been prepared (Table 1).

Table 2 presents the performance indicators of the quality of the proposed compositions of coolant concentrate and 3% solution of this coolant concentrate.

Working solutions at a concentration of 2-5% have sufficient anti-corrosion properties, the pH of the solutions is in the range of 8-9.

Tests of the prototype and proposed compositions of the coolant were carried out on an experimental setup for MAO model EU-1 with the following parameters: the value of magnetic induction in the working gap, 1.0 T, the speed of rotation of the part, 2.5 m/s, the speed of oscillation of the part, 0.12 m/s, oscillation amplitude, 2.0 mm, working gap, 1.0 mm, processing time, 60 s. As a ferroabrasive powder, Zh15KT TU 6-09-03-483-81 was used, the grain size of which is 200-315 μm. The initial roughness of the surfaces of the samples is 1.2-1.4 microns. Bushings made of ball-bearing steel and aluminum alloy ShKh15 GOST 801-78 and D16 GOST 4784-97, respectively, were used as samples, which were mounted on a ferromagnetic mandrel. Bushing dimensions: diameter 36.0 mm, length 32.0 mm, wall thickness 1.0 mm. During the test, metal mass removal (AG) and surface roughness (Ra) were evaluated.

Mass removal of metal is defined as the ratio of the masses of samples before and after MAO. The weight of the initial samples was 28 and 10 g, respectively, the samples were weighed on a laboratory balance model VLA-200-2M with an accuracy of ±0.001 g. The study of the surface roughness of the samples was carried out on a profilograph-profilometer model 250 of the Kalibr plant by fixing the data on the profilogram. The value of indicators for these MAO conditions was determined as the arithmetic mean of the results of measurements on five samples.

The test results of the prototype and the proposed compositions are shown in table 3.

As a result of the tests (Table 3), it was found that composition No. 2 of the proposed coolant concentrate is optimal. It has improved technological performance in terms of processing performance (1.17-1.22 times) and surface roughness (1.27-2.0 times). This composition has good technological properties that increase the productivity of MAO and reduce the roughness of the treated surfaces. For composition No. 1, an increase in the amount of water leads to a decrease in cutting and washing ability. Due to the decrease in the amount of water for composition No. 3, the lubricating and washing properties of the coolant are reduced, which is associated with incomplete dissolution of sodium nitrite and potassium hydroxide.

Information sources

1. A.S. 1055757, IPC S10M 3/02, 1983.

2. A.s. 1740404, IPC S10M 173/02, 1992.

3. RF patent No. 1814307, IPC S10M 173/00, 1995.

4. RF patent No. 2148622, IPC S10M 173/00, 2000 (prototype).

Claims (2)

Coolant concentrate, which can be used in the form of an aqueous solution in the engineering industry for operations of magnetic abrasive processing (MAO) of non-ferrous metals, steels and their alloys, containing triethanolamine soap of synthetic fatty acids C ₇ -C ₉ , oleic acid, potassium hydroxide, sodium nitrite, industrial oil and water, characterized in that it additionally contains sodium sulfoethoxylate, wt.%: triethanolamine soap of synthetic fatty acids С ₇ -С ₉ 30.0-50.0 oleic acid 10.0-15.0 sodium sulfoethoxylate 5.0-10.0 potassium hydroxide 2.0 sodium nitrite 2.0 industrial oil 2.0-4.0 water rest