EA023963B1 - Grease lubricant composition and method for producing the same - Google Patents

Abstract

The invention is related to grease lubricants, in particular, to compositions where either light low-temperature mineral oils such as transformer or instrument oils, or synthetic oils such as polyalphaolefin or alkylaromatic are used as a disperse medium. The object of the invention is provision of a stable grease lubricant with ultra-low temperature properties, scoring resistant properties and colloid stability. The essence of the invention is that addition of non-hydrated polyalphaolefin fraction C-Cwith a chilling point down to -60°C as a sulphurised agent allows to obtain a highly efficient grease lubricant with an ultra-low temperature range (-70°C), improved scoring resistant properties and high colloid stability.

Description

The invention relates to grease, and in particular to compositions where either light low-temperature mineral oils, for example transformer or instrument oils, or synthetic oils, for example polyalphaolefin or alkyl aromatic, are used as a dispersed medium.

Lubricants are used in transport equipment, material handling equipment, mechanical engineering, as well as in industrial devices and machines. In rolling bearings and sliding bearings, lubricants are designed so that between the sliding or sliding on each other parts an intermediate load-transmitting lubricating film is created so that the metal surfaces do not come into contact and thereby wear of the parts does not occur. Therefore, high requirements are imposed on lubricants, namely, silent rotation of bearings, and the duration of a lubricant's life without replenishment of lubricant. Lubricants must withstand forces such as centrifugal force, gravity and vibrations.

It should be noted that almost all low-temperature lubricants of the post-Soviet production (for example, TsIATIM-203, LITA, ZIMOL, LZ-TsNII), as well as their foreign counterparts, have very low stability (from 10 to 30% of the extracted oil) and low extreme pressure properties which do not allow their use in rotating bearings at speeds above 10 thousand rpm.

Known grease (plastic) based on polyalphaolefin oil with a viscosity of 18-22 cSt at 100 ° C, thickened with complex calcium soap of stearic and acetic acids, containing graphite and antioxidant additives: phenyl-a-naphthylamine and ionol (RF patent No. 2233313, 2004 g.).

The disadvantages of this lubricant are the tendency to harden upon contact with water vapor and insufficient protective properties against corrosion.

Known plastic grease used to lubricate heavily loaded friction units, such as friction units of wheel hubs or steering cars. The lubricant contains mineral oil-extract of selective oil purification, calcium soap of synthetic fatty acids of the fraction C ₅ -C ₉ , C ₇ -C ₉ , C ₂₂ and higher (RF patent No. 2169171, 1999),

The disadvantages of the known lubricants are low dropping point (85-90 ° C), low antiwear properties.

Known lubricant containing, wt.%: 12-oxystearic acid 14-0; acetic acid 4-5.8; synthetic fatty acids of the C ₅ -C ₆ fraction or hexanoic acid 1.5-2.5; eight-water barium hydroxide until complete saponification; And (diethylamymethyl) benzotriazole 0.01-0.3; synthetic polyalphaolefin oil with a viscosity of 5-12 cSt at 100 ° C to 100 (RF patent No. 2391386, 2008).

A disadvantage of the known lubricant is the relatively low colloidal stability when using a less viscous base oil (less than 5 cSt at 100 ° C).

Closest to the claimed method relates to a complex grease by mixing mineral oil, a complexing agent - acetic acid, sulfonated organic compounds, followed by saponification of the mixture with calcium hydroxide when heating the soap-oil system at a cooking temperature of the lubricant, cooling and homogenization, before saponification, it is introduced into the system as sulfomass, industrial vegetable oil sulfonated with concentrated sulfuric acid at a ratio of sulfuric acid to technical CB vegetable oil 1: 5.7, at a ratio sulfomassy System 1: 5-7, and acetic acid was added to the reaction system in an amount of 4% by weight (Eurasian patent № 018494, 2013 YG)

A disadvantage of the known lubricant is the relatively low pour point of vegetable oils, which, in turn, does not allow to obtain a lubricant with ultra-low temperature properties and relatively low colloidal stability.

The objective of the invention is to provide a stable grease with ultra-low temperature and extreme pressure properties against corrosion, as well as colloidal stability.

The problem is solved by the method of obtaining a complex grease by mixing mineral oil, a complexing agent - acetic acid in an amount of 4% of the total mass, sulfonated organic compounds of sulfomass, followed by saponification of the mixture with calcium hydroxide when heating the soap-oil system at a cooking temperature of the lubricant, its cooling and homogenization moreover, the ratio of sulfomass to the system is 1: 5-7, where according to the invention, nonhydri are introduced into the system before saponification as sulfomass the polyalphaolefin fraction C ₂₀ -C ₃₀ sulfonated with concentrated sulfuric acid at a ratio of sulfuric acid to polyalphaolefins of 1: 4-5.

The essence of the invention is that before saponification, a C20-C30 polyalphaolefin fraction is introduced as a sulfonating agent with a pour point of up to -60 ° C, which makes it possible to obtain a high-performance lubricant with an ultra-low temperature interval (-70 ° C), improved extreme pressure properties and a high colloid stability.

When the ratio of sulfuric acid to polyalphaolefin fraction below the claimed limit, polyalphaolefins are sulfonated, which leads to a deterioration in quality indicators

- 1 023963 of the products received, and the increase in the ratio is impractical, because there is an overrun of the initial products.

The introduction of sulfomass in the composition below the claimed limit leads to a deterioration of almost all indicators of the product, and an increase leads to a decrease in the penetration of the lubricant.

Lubrication is prepared as follows.

The calculated amount of the C20-C30 polyalphaolefin fraction is poured into the container, then, with vigorous stirring, the calculated amount of concentrated sulfuric acid (96%) is introduced through a dropper over 10 minutes. Since the process is exothermic, it is first conducted with cooling, and then heated so that the temperature of the reaction zone is kept within 50-55 ° C. After the sulfuric acid supply is complete, stirring is continued for another 10 minutes. The resulting sulfomass is added to the calculated amount of the base oil (for example, transformer oil) with constant stirring, and the complexing agent, acetic acid in the amount of 4% of the total mass, is then added thereto, and then a suspension of calcium hydroxide to neutralize the reaction medium to a slightly alkaline reaction, and turn on heating for cooking grease at a temperature of 130 ° C with constant stirring until the moisture is completely removed. After that, the heating is turned off and the grease is allowed to cool to room temperature. Then conduct an analysis of the main indicators of the quality of the sample of the obtained lubricant.

The composition and properties of the proposed grease are presented in table. 1-3.

For convenience, comparing quality indicators in the table. 3 shows the quality indicators of low-temperature commodity lubricants: railway lubricant LZ-TsNII (GOST 19791-74) and LIMOL (TU-38.301 48-54-95).

As can be seen from the table, subject to the ratios of sulfuric acid to polyalphaolefins (1: 4-5) and sulfomass to the system (1: 5-7), the obtained samples fully meet the requirements for lubricants with great superiority over the known ones.

Thus, using the C20-C30 non-hydrogenated polyalphaolefin fraction with a low pour point as a sulfonating agent, it is possible to obtain an ultra-low-temperature lubricant operating at a temperature of -70 ° C while maintaining good pumpability. In addition, the obtained samples of lubricants in this way have high tribological properties, colloidal stability and a low coefficient of thermal hardening.

Table 1

No. Names GO Examples l indicators ST one 2 3 4 5 6 7 8 nine 10 eleven 12 thirteen 14 fifteen sixteen Ζ s η one Penetration with mix. After 60 double blows., Mm / 10 $ 34 " > <20 > 420 400 * " 350 325 305 200 200 200 245 255 225 255 285 295 2 The temperature of the droplets., ° C "753 105 205 240 250 > 250 250 > 250 > 250 > 250 > 250 250 250 250 " 3 Colloidal stability,% 7142 "L 4L al al 2,5 1L M 1D and 2L 2L 2L al 4.2 4 Effective viscosity at -50 ° C and strain rate. 10 ^e · ¹ , Pa «s 7143 0 0 0 fifty in and about 12 $ 155 105 250 340 - "twenty 500 540 545 5 Strength at 50 ° С, Pa 7143 220 225 230 250 255 200 310 340 405 410 405 335 300 155 525 310 6 Corrosion test 5757 • md • MD • md • md MD • md • md. - • MD- md. • md md 0 * 1 md

- 2 023963

Table 3

No. p / p The name of indicators Norm Nd on method trials zznii LIMOLE one Penetration with stirring after 60 double strokes, mm / 10 230-260 250-310 GOST 5346 2 Drop point, not lower ⁱⁿ C 130 140 GOST 6793 3 Colloidal stability %, no more 24 10 GOST 7142 4 Effective viscosity at -5 (GS and strain rate 10 ^e ' ^1. P a.s. no more 1100 2000 GOST 7163 5 Badass Index, not less 60 GOST 9490-75 6 Corrosion test Aging Aging GOST 5757

CLAIM

Claims (1)

A method of obtaining a complex grease by mixing mineral oil, a complexing agent - acetic acid in an amount of 4% of the total mass, sulfonated organic sulfomass compounds, followed by saponification of the mixture with calcium hydroxide when heating the soap-oil system at a cooking temperature of the lubricant, its cooling and homogenization, the ratio sulfomasses to the system is 1: 5-7, characterized in that before saponification as a sulfomass, a non-hydrogenated polyalphaolefin fraction is introduced into the system C20-C30 sulfonated with concentrated sulfuric acid at a ratio of sulfuric acid to polyalphaolefins