SU1728295A1 - Lubricating and cooling liquid for cold metals rolling - Google Patents

Description

The lubricant is prepared by mixing a 30% aqueous solution of the oxidized lignosulfonate with a calculated amount of a 30% dispersion of the graft copolymer of polymethylmethacrylate grafted with lignosulfate, as well as triethanolamine and sulfonol. The resulting mixture, heated to 70–75 ° C, contains the calculated amount of synthetic fatty acids and polyethylene (polyolefin) with a mass of 1,500–20,000 mol. The mixture is then diluted with water to the required concentration and cooled with stirring.

In comparison with analogs, a known lubricant has improved antifriction properties, which makes it possible to use it in rolling hard-to-deform steels. For example, when rolling electrical steel E 311 with a force of 195 kN and a speed of 20 m / min, the coefficient of friction is 0.039, and the surface roughness is 0.34 µm.

The disadvantage of this coolant composition is the increased viscosity (more than 100 mm2 / s) and the impossibility of diluting it to a well-flowing fluid due to the low colloidal stability of the latter. The resulting emulsions quickly exfoliate. At the same time, the high viscosity of the lubricant is the cause of the inefficiency of cooling, which leads to the heating of the rolls, their vibration, seizure, and reduces the service life. The high viscosity of the lubricant does not allow it to be irrigated by the cooling system. Lubrication is applied by dipping, smearing, which is unproductive.

The aim of the invention is to reduce viscosity, increase anti-friction properties and quality of the treated surface.

Cooling lubricant for cold rolling of metals, containing a graft copolymer of polymethyl methacrylate with lignosulfonate, a molecular weight polyolefin of 1500-20000, and water, additionally contains sulphate soap, copper oleic acid and mineral oil with a weight ratio of the latter to polyolefin of 1.4 - 2.0, and as a polyolefin contains polyethylene, or polypropylene, or polyisobutylene in the following ratio of components, wt.%:

Graft copolymer

polymethyl methacrylate

with lignosulfonate1-3

Polyolefin

molecular

masses 1500-200002-5

Sulfate Soap3-8

Oleic acid copper 0,2 - 0,5

Mineral oil4-7

WaterUnder 100

To reduce the viscosity of the oil phase and determine the optimal concentration of the polyolefin in the oil solution, the kinematic viscosity of the solution is evaluated according to GOST. A solution of polyethylene in mineral oil I-12 is prepared at 30–90 ° C with stirring for 0.5–3.0 h.

The results are shown in table 1.

As can be seen from the data of Table 1, the viscosity of a solution of polyethylene in oil is significantly lower than the viscosity of the original polyethylene, and the optimum ratios of mineral oil / polyethylene are 4/2 - 7/5, since a further decrease in the ratio does not lead to a significant decrease in viscosity (example 1), and an increase in this ratio leads to a significant increase in viscosity.

The use of oil as a solvent makes it possible to expand the molecular weight range of the polyolefin and to use in the lubricant composition a number of other polyolefins (polypropylene, polyisobutylene) which are solids and, in the suggested molecular weight range, have good oil solubility.

Data on the possibility of using polyolefins with a molecular weight of 1500 -. 20,000 in an oil solution without compromising its viscosity is given in Table 2 (the ratio of mineral oil / polyolefin is 1.7).

The solubility of polyolefins with a molecular weight above 20,000 in oil is significantly lower and does not allow the required concentrations to be reached.

To reduce the viscosity of the aqueous phase of the lubricant, it is proposed to reduce the content of graft copolymer of polymethyl methacrylate with lignosulfonate. Graft copolymer of polymethyl methacrylate with lignosulfonate is obtained by radical polymerization of 20 parts by weight. methyl methacrylate in 80 wt.h. 10% aqueous solution of sodium lignosulfonate at the initiation of 0.2 wt.h. 10% aqueous solution of hydrogen peroxide.

The data are given in table 3.

As can be seen from the data of Table 3, the kinematic viscosity of aqueous solutions of the graft copolymer is much lower than the viscosity of the known composition. The decrease in the concentration of graft copolymerization below 1 May. % does not lead to a further decrease in the viscosity of the solution, while an increase in concentration above 3 wt.% significantly increases its viscosity. Thus, concentrations of 1-3% by weight are optimal.

By mixing an aqueous solution of the graft copolymerizate with an oil solution of a polyolefin, an unstable dispersion is obtained, which stratifies within a few seconds. Therefore, sulfate soap is used as a dispersion stabilizer. The dispersion stability is determined according to GOST. To determine the optimal concentration of sulphate soap, the compositions presented in Table 4 were prepared.

In the specified composition, in addition to sulfate soap, it contains in wt.%: Poly (methyl methacrylate) graft with co-polymer with lignosulfonate 2; molecular weight polyethylene 1500 - 20000 3; mineral oil 5; water up to 100.

Sulfate soap is a viscous dark brown mass with a slight odor that dissolves well in water. Sulfate soap is a sulphate pulp production waste.

As can be seen from the data of Table 4, at a concentration of sulphate soap below 3 wt.%, The dispersion is unstable, and at a concentration above B wt.%, A white cream is observed (oil stains on the surface of the liquid). Thus, the optimum concentration of sulphate soap is 3-8% by weight.

To increase the antifriction properties of the resulting composition in the composition with the optimal content of graft copolymer of polymethyl methacrylate with lignosulfonate (2 wt.%), Polyethylene (3 wt.%), Mineral oil (5 wt.%) And sulphate soap (5 wt.%) oleic acid copper. The antifriction properties of the compositions are evaluated by the coefficient of friction, which is determined on a Falex-1 friction machine. Test mode: speed - 0.2 m / s, test duration 60 minutes, a pair of friction block - ring.

The data obtained are given in table.5.

As follows from the data of Table 5, when the copper oleate content is less than 0.2 wt.%, There is a slight improvement in the antifriction properties compared to the known composition, and when the copper oleate content is higher than 0.5 wt.%, They are slightly worse than the optimum content . Thus optimal

the concentration of copper oleic acid is 0.2-0.5 wt.%.

The following coolant compositions were prepared for the technological tests (Table 6).

The proposed lubricant is prepared as follows.

The calculated amount of mineral oil is loaded into the container, heated to 60–70 ° C and the required amount of polyolefin and copper oleic acid is added with stirring. The mixture is stirred at this temperature for 1 to 3 hours until the polymer is completely dissolved. In another container, the calculated amount is mixed

sulfate soap with a graft copolymer dispersion dispersion. The mixture is heated to 60-65 ° C and a solution of polyolefin in oil is gradually introduced with continuous stirring. Cool the resulting dispersion

to room temperature with stirring. The resulting mass is diluted with water to the desired concentration.

Technological properties of the proposed composition with optimal content

components are estimated by welding load (Pc is the smallest load at which the balls are welded, which characterizes the lubricity limit), critical load (Pk is the load at which there is a sharp increase in the wear of the balls) and the coefficient of friction. The parameters Pc and Pc are determined by the standard method on a four-ball friction machine. Rolling is carried out on

at the speed of 20 m / min on E 311 electrical steel specimens with dimensions of 200 x 30 x 0.81 mm.

The research results are summarized in table 7.

As can be seen from the data presented in Table 7, the proposed composition has higher lubricating and antifriction properties as compared with the known.

The tests carried out showed that the use of the proposed lubricant composition with an optimal ratio of components allows preparing a stable emulsion, reducing the viscosity of the lubricant, which

increases the heat sink from the processed part, to improve the quality of the processed surface,

Formula of the Invention Cooling lubricant for cold rolling of metals containing water, grafted polymethyl methacrylate copolymer with lignosulfonate and polyolefin of molecular weight 1500-20000, which is

decrease in viscosity, increase the antifriction properties of the liquid and the quality of the treated surface; the liquid contains polyethylene or polypropylene or polyisobutylene and additionally sulfate-tallow, oleic acid copper and mineral oil at a mass ratio of the latter to the polyolefin of 1.4-2.0 in the following ratio of components , wt.%: Graft copolymerizate

0

polymethyl methacrylate with lignosulfonate Polyethylene, or polypropylene, or polyisobutylene molecular weight 1500-20000 Oleic acid sulfate soap copper Mineral oil Water

2-5 3-8 0.2 - 0.5 4-7 Else

15

Table 1

Table 2

Table3

Table4

Table 5

Table 6

Table

Claims (1)

Claim Cutting lubricant for cold rolling of metals containing water, grafted copolymerizate of polymethyl methacrylate with lignosulfonate and a molecular weight polyolefin of 1500 - 20,000, characterized in that, in order to reduce viscosity, increase the antifriction properties of the liquid and the quality of the treated surface, the liquid contains polyethylene as a polyolefin or polypropylene or polyisobutylene and optionally 5 sulfate soap, oleic acid copper and mineral oil with a mass ratio of the latter to the polyolefin of 1.4 - 2.0 at the following ratio of components, wt.%: 10 Grafted copolymerizate of polymethyl methacrylate with lignosulfonate 1-3 Polyethylene, or polypropylene, or polyisobutylene, molecular weight 1500 - 200002 - 5 Sulphate soap 3-8 Oleic acid copper 0.2 - 0.5 Mineral Oil 4-7 Water Else Indicator, component The content of the component, May, for examples Source polyethylene 1 2 3 4 5 Polyethylene 1 2 3 5 7 Mineral oil 3 4 5 7 8 Mineral oil 3 2 1.7 1.4 1,1 Polyethylene Kinematic viscosity, mm ² / s 47 61 98 139 250 Over 350 Table 2 Indicator Molecular weight polyethylene Polypropylene Polyisobutylene 1500-3000 15000-20000 Kinematic viscosity Λ mm / s 78 102 126 132 Table 3 Indicator Famous The concentration of the grafted copolymerizate of polymethyl methacrylate with lignosulfonate, May. % 0.5 1 2 3 5 Kinematic viscosity, mm ² / s More than 100 9.8 9.9 10.3 13,2 25,4 Table4 I Indicator The content of sulfate soap, May.% 1 3 5 8 • 10 GOST STABILITY Not withstand Withstands Withstands Withstands Not withstand Table 5 Indicator Famous The content of oleic acid copper, May.% 0.1 0.2 0.3 0.5 0.7 Coefficient of friction under load, N 450 0,07 0,062 0,050 0,045 0,047 0,055 2500 0.06 0,048 0,040 0,032 0,030 0,038 Table 6 Composition Concentration, May. % by examples 1 2 3 4 5 Graft polymethyl methacrylate copolymerizate with 1 2 3 2 2 lignosulfonate Molecular polyethylene 2 3 5 0 0 masses 1500-20000 Polypropylene molecular 0 0 0 5 0 masses 1500-20000 Polyisobutylene molecular 0 0 0 0 5 masses 1500-20000 Sulfate Soap 3 5 8 5 5 Oleic acid copper 0.2 0.3 0.5 0.3 0.3 Mineral oil _4_ . . -5 . 7 A B Water Up to 100 Table 7 Indicator Famous The proposed composition by examples 1 2 3 4 5 RK.N 1500 2660 2990 2990 3150 3760 RS.N Friction coefficient under load, N 7800 7200 8000 7800 8000 10,000 450 0.08 0.05 0,045 0,047 0,045 0,042 2500 kinematic viscosity 0.06 0,038 0,025 0,025 0,023 0,020 mm ² / s Stability 107 11.2 13.5 16.0 17.8 18.2 according to GOST Roughness Aging Aging Aging Aging Aging Aging surface P, microns 0.34 o; s2 0.30 0.32 0.30 , 0.30