DE945174C - Process for the production of lubricating greases - Google Patents

Description

ISSUED JULY 5, 1956

St 6156 IVc 123c

is ^ n claimed

The invention relates to a method for the production of lubricating greases, after which to achieve a maximum dispersion of the soap shear stress fields can be applied without this intermixing the crowd enters.

The invention also relates to a method for producing roller bearing greases, after which one Mineral oil or a synthetic oil of high V.l. (From left = viscosity index) a mixture of mixed soaps forming substances and an oil with a low V.l. adds, the mixture cools quickly and then exposed to the action of high shear rates without simultaneous mixing of the mass.

In the known production of soap-thickened lubricating greases, the soap in the mineral oil is under Heating dispersed. After the soap has completely melted, the final distribution is brought about. The actual formation of the solid fat phase takes place through crystallization of the dispersed soap on cooling. In order to obtain a sufficiently stable structure from which no oil can be obtained after this process excreted, you have to use enough soap so that the oil in the fat structure through with each other connected fat crystals is included. According to the present invention, the fat becomes more common Way by heating the mixture of oil and soap

and subsequent cooling and crystallization, but it is also mechanical Energy used as another means of dispersing the soap.

After the soap has crystallized and the fat structure has formed becomes the relatively cool fat of the action of shear stress fields without simultaneous exposed to mechanical mixing. With this treatment, the soap becomes more effective and more even ίο more dispersed than was previously thought possible would have. The advantage of this more complete dispersion of the soap is that it can be used to make fats consistency requires considerably less soap than with previous methods. With lesser ones Soap content, the thioxothropy of the soap thickener can be better regulated, and in addition the Easily adjust the penetration of the finished product to the desired value.

The shear effect disperses the soap in the form of a highly oriented linear structure. Except With this linear orientation, the small bundles or micelles of the soap crystals are sheared into a plane, and the dispersion obtained approaches the finest possible distribution. The fat won't be Subjected to mechanical stirring or mixing, this dispersion is retained in the fat. Will However, if the fat is mechanically stirred or mixed after the action of the shear force, then this is done The particular type of dispersion destroys and the soap particles or crystals aggregate to form a dispersion together, as it is in the previously common lubricating greases.

It is therefore essential for the purposes of the invention that

after the action of the shear forces, and preferably also before and during their action,

■ there is no mechanical mixing of the fat.

Shear rates of about 10,000 to 500,000 sec- ¹ or more are preferred. A substantial increase in consistency can be obtained with a shear rate of about 10,000 sec- ¹ or more, and the consistency of the finished product can be precisely controlled in this range by the shear rate be. For industrial purposes, shear rates in the range of 100 000 and 400 000 sea- usually required. ¹

When carrying out the method according to the invention, the fat is first processed in the usual manner and then subjected to a shear force without mechanical agitation or mixing by you can travel a laminar flow path at high speed and under high pressure leaves. This can be done in a simple manner in a Gauhn homogenizing machine be done in which the fat is under high pressure through a pipe and then on leaving of the tube pressed through an annular channel that of a spring loaded conical valve or plug and a

■ Corresponding conical socket at the outlet end of the pipe is formed. For the same purpose you can also use roller mills, in which the fat is driven through between steel rollers with a very small distance from each other, or the known Morehouse mills are used in which the material is placed between high-speed discs with very little Gap width goes through. A pressure viscometer can also be used use if it is operated with sufficiently high pressure. Others with shear effects too working devices can be used provided that no simultaneous mixing of the good takes place.

The method according to the invention is applicable to fats in which the thickener is made up of mixed soaps consists of two or more components. Mixed soap fats made from rapeseed oil soaps and fats that contain Complex high molecular weight soaps and low molecular weight salts such as acetates, furancarboxylic acid Salted acrylates are thickened, are produced by the process according to the invention. Fats with Simple fatty acid soaps are thickened apparently cannot be made using the method described above produce.

According to one embodiment of the invention, the lubricating grease is initially formed as follows:

Refined, unblown rapeseed oil and an equal to double amount of lubricating oil are placed in a directly heated fat kettle together with small amounts of the sodium salt of a petroleum sulfonate. The kettle is equipped with a powerful stirrer or with mixing paddles. Sufficient sodium hydroxide solution is then added to the kettle so that there is an excess of 0.3 to 0.6% sodium hydroxide, based on the finished fat. The mass is heated to about 120 ° until the soap is completely saponified and dehydrated. Now the rest of the oil is added and the mass is slowly ^{heated to about 260 0} until the mass is completely melted. The mixture is then cooled with stirring to 93 ^0th During the cooling process, the soap recrystallizes, after which inhibitors are added.

When using this procedure, around 20 to 50% soap is required to use a fat a worked penetration of 200 to 350 mm / 10 after 60 thrusts. This as far as known per se Well-made grease is excellent for lubricating ball bearings.

According to the invention, the following operation now follows:

After cooling the mass to about 93 ° and adding ¹¹ additives, another part by volume of oil is added to the mass. This additional oil, which may be a mineral or synthetic product, sets the soap content to about 6 to 18 ° / ₀ decreased. The fat obtained in this way does not have the desired fat structure, but rather a semi-liquid mass which is not suitable for the lubrication of roller bearings. This semi-liquid mass is then subjected to high shear rates without mechanical mixing.

If you try a grease from the sodium soap of unblown rapeseed oil, which is only 6 to. contains i8 ° / ₀ soap, make the hitherto conventional way, we obtain a fat, its structural stability harbors far below that which is necessary for use as a rolling bearing, high-temperature grease. Obtained by the process according to the invention

However, if a fat having a content of only 6 to i8 ° / ₀ soap, which is useful as a lubricant of roller bearings with a long service life and stable against retrogradation.

As the synthetic lubricating oil for blending the mixed soap grease, any of known synthetic Oils are used. In general, synthetic ester-based lubricants are recommended, z. B. the esters of monobasic or polybasic acids,

ίο Esters of glycols, polymerized glycols, glycol ethers, mixed esters such as alcohol-dibasic acid-glycol esters or alcohol-dibasic acid-glycol monobasic acid esters or mixtures of esters. In general, esters having from about 10 to 30 carbon atoms with branched or straight chains are preferred. Examples of particularly preferred synthetic lubricating oils are: di-2-ethylhexyl sebacate, dioctyl sebacate, di-nonyl sebacate, di-2-ethylhexyl adipate, di-C ₇ oxoadipate, di-C ₈ oxoadipate, di-C ₁₃ oxoadipate, and more Mixed esters, such as those prepared by reacting two moles of a half ester of a C ₄ - to C ₁₀ -AlkO-hol and a dibasic acid with one mole of a polyethylene glycol, as well as mixtures of the abovementioned compounds.

In addition to the ester-based synthetic lubricating oils, other synthetic oils can also be used will. Polymerized silicone oils, long-chain formals, carbonic acid esters, polymerized olefins, copolymers aliphatic and aromatic compounds "30, etc. are also in the method of the invention usable; the only condition that these synthetic lubricating oils must meet as blending oils, is their suitability in relation to the finished grease. The following examples serve to illustrate the invention.

example 1
Rapeseed oil

A fat of the following composition was prepared in the following manner:

Weight percent
20.9

I ₁ O

o, 5

Components'
Sodium soap from rapeseed oil
Oxidation retarder (P.henyl-

a-naphthylamine)
Metal deactivator (condensation product of propylenediamine and salicylaldehyde) i, o stabilizer (sodium petroleum

sulfonate)

76.6 mineral oil (coastal type) viscose

ity 6.3 cSt at 98.9 °.

Procedure: The Rübölseifeund half of mineral were introduced into a heated fat kettle and heated to about 204 ^0th At 260 ^° the heating was interrupted, the remaining amount of oil was added, the molten mass was pumped into a cooling vessel and cooled there with stirring. At 113 ⁰ the inhibitors were added, then the fat was drawn off, filtered and cooled in cooling pans.

A sample of this fat was then driven six times through ^{a Gaulin homogenizer at 211 kg / cm 2.} This application of shear forces without simultaneous mixing made the fat hard as a result of the better dispersion of the soap.

Tabel I. To
use
the
Shear force before
use
the
Shear force 178 Walk penetration after
60 thrusts, mm / 10 286

Example 2

The grease according to Example 1 was blended in the grease kettle of 100 ° / ₀ mineral oil. The mixture was soft and runny. This cut product was subjected to various shear rates in a pressure viscometer. In this apparatus, the fat was forced through a capillary 0.4 mm in diameter and 16 mm in length using varying pressures up to 211 kg / cm ² . The flow rate was determined by collecting the fat flowing out in a measured time. The shear rate in sec ^-1

became from Poiseuille's formula

π · R ³

he

calculates where Q is the flow velocity in parts of space per second and R is the radius of the capillary. After the sample had flowed through the pressure viscometer, it was allowed to cool to room temperature (25 °). After processing in a micro-grease kneader with 4 strokes, the micro-penetration was determined using a sieve with a mesh size of 0.25 mm.

The values obtained are given in Table II:

Table II

These values are entered in FIG. It can be seen that the hardening effect is greatest at shear rates up to 100,000 sec- ¹ . Although shear rates up to 500,000 sec- ¹ are effective, the slope of the curve is less than at lower shear rates. It can also be seen that shear rates of up to about 400,000 sec- ¹ are practically usable, with shear rates of 100,000 to 400,000 being preferred and those of 150,000 to 250 ooosec- ^{1 being} particularly preferred.

Micro-walk penetration Shear rate in mm / 10 see— ^x after 4 thrusts in the micro-fat mixer _ 157 2I, 8oo 123 63,800 106 184,000 98 278,000 99 413,000 97 534,000 94

By choosing the appropriate shear rate, you can get greases of the desired hardness produce.

Example 3
5

Effect of the method according to the invention
on the fat ratios

Teü A

After the usual method in the Schmierfettechnik a grease was prepared which contained 23.8 ° / ₀ sodium soap of rapeseed oil and 76.2% mineral oil. This fat was divided into two parts. Part B was used in a Gaulin homogenizer

x5 homogenized at a pressure of 210 kg / cm ² , while portion A was not homogenized. The samples were then tested for ASTM penetration and dropping point. In addition, they were stored at 98.9 ° for 30 days and at normal temperature for 30 days. They were also subjected to the ASTM Wheel Bearing Test described in the Appendix to the November 1948 ASTM Manual. In this test, the sample in'ein normal Ford-wheel bearing is introduced and this 6 hours at 104 ⁰ at 440 U / min run. If the sample fails or oil leaks from the bearing after testing, the result is unsatisfactory.

The grease samples were also subjected to spindle testing by the Annular Bearing Engineering Committee and the National Lubricants and Grease Institute. In this test, the sample is used to lubricate a journal bearing No. 204 which is operated at 121 ° at 10,000 rpm until it fails. The results are displayed in hours «resp. Lubricating time of the grease specified. Also, the fat samples were. subjected to the Norma Hoffmann oxidation test. For this purpose, a sample of the fat is placed in an oxygen bomb and oxygen up to. initiated at a certain pressure. The bomb is then kept at constant temperature until a pressure drop of 0.3 kg / cm ² has occurred, and the result is given in hours.

^{part B}

A grease blend containing about 18.7% sodium soap from raw rapeseed oil was prepared in accordance with the invention, that is, a base grease containing about 30% soap was first prepared. This was then cooled to below the solidification ^{temperature (below about 93 0} ). Now so much mineral oil was added to the mass that its soap content was about 18.7%, based on the finished product. Part A was not homogenized, Part B was driven through a Gaulin homogenizing machine at a pressure of about 210 kg / cm ² . The products have now been subjected to the tests described in Part A.

Part C.

A further accordance with the invention prepared fat containing about 12 ° / ₀ sodium soap of rapeseed oil. Part A of this was not homogenized, but part B. These samples were subjected to the same tests. The key figures obtained in this way are given in Table III.

Table III

Effect of homogenization at high shear speeds Gaulin homogenizer - pressure: 210 kg / cm ²

composition

Part A
Part A Part B Part B
Part AI Part B

Teü C Part A I Part B

% Soap

% Mineral oil.
properties

Spible test at 10,000 rpm
(Ball bearing no.204 at 121 °),
hours

Penetration at 25 °, mm / 10
Resting penetration

Walk penetration (60 strokes)

Drop point, ⁰ C

Bleeding after 3 days of storage

Wheel bearing test

Oxidation resistance according to

Norma-Hoffmann (hours to
to the drop in oxygen pressure
around 0.3 kg / cm ² )

23.8
76.2

not
homogenized

1315

278

• 286.
> 260

noticeably
enough

260

homogenized

1315

158

173 ·>

none is sufficient

260 18.7
81.3

not
homogenized

-363
344

strong

enough

homogenized

930

182
201
232
none
enough

12.0 88.0

not homogenized

too soft

strong

enough

not

homogenized

770

262

275 204 none is sufficient

340

The Part A grease, Part A, gave excellent results on all tests except regarding bleeding. After 3 days of storage, noticeable amounts of oil had separated out. The worked penetration of 286mm / io is clearly within the permissible limits of 200 to 350. Part B subjected to homogenization was far too hard to smear Roller bearings. A comparison of the proportions A and B of the

Parts B and C clearly show the advantages of the present process. The proportions A show that the fat with low soap content is too low in consistency without homogenization. the However, proportions B show that, in addition to approximately twice the fat yield, by homogenization, excellent, Smooth, lubricious products are obtained without any noticeable even after 30 days of storage Bleeding occurs.

The fats from Part A, Part B, and Part C, Part B, according to Table III were placed in a roller bearing tested, which was operated for 300 hours at working temperatures of 38 to 71 °. Part A of part A had a penetration of 173 after the test. This hardening is attributable to the high soap content and makes the grease unsuitable for lubricating roller bearings. The fat sample part C, however did not change its consistency.

Example 4

Lithium mixed soap grease based on mineral oil

Following the procedure described below, a grease of the following composition was obtained manufactured:

Components by weight

Hydrogenated fish transacids 20.0

Glacial acetic acid 4.0

Lithium hydroxide monohydrate. 6.2

Inhibitor according to Example 1 ... 1.0

Mineral oil (coastal oil), viscosity

6.3 cSt / 98.9 ⁰ 68.8

Procedure: The fish transacids and half of the mineral oil were in a directly heated fat kettle entered and heated to 66 ° with stirring. Then the glacial acetic acid became, and immediately after that, the Lithium hydroxide added as a 10% aqueous solution. The temperature was increased to 104 to 121 ° and then the remaining mineral oil was added, while the temperature continued to rise to 271 °. Then the inhibitor was added and the entire mixture cooled with stirring. Further mineral oil was added at 93 °. The finished mass contained about 12% Soap and on cooling gave a soft, lubricious product.

A portion of the fat was subjected to a high shear rate without simultaneous mixing by forcing it three times through a Gaulm homogenizer ^{under a pressure of 352 kg / cm 2.} A second portion of the fat was diluted with further mineral oil to a soap content of 6%. This product was soft and semi-liquid and was forced through a Gaulin homogenizer at 352 kg / cm ² . The penetration values of the fat samples are given in Table IV:

Table IV

Walk penetration after
60 thrusts, mm / 10

After dilution to 6%
soap

Original
fat

350

To
use

the
Shear force

167
284

• These tests show that lithium mixed soap greases can be produced using the method according to the invention can be produced advantageously.

Example 5
Furfural fat

A furfural grease of the following composition was prepared using the method described below:

Components

Furfural

Hydrogenated fish transacids ....

Sodium hydroxide

Oxidation inhibitor according to

example 1

Mineral oil (coastal oil), viscosity

3.2cSt / ₉ 8.9 °

Mineral oil (coastal oil), viscosity

12 cSt / 98.9 °

Weight percent

10.6
15.0
5.38

1.0
30.0
38.62

Procedure: The light mineral oil and fish transacids were placed in a steam-heated fat kettle. The sodium hydroxide was then added as a 40% strength aqueous solution. The temperature increased to about 38 to 41 °. Now the furfural was added. The aldehyde entered into a Cannizzaro reaction with the excess sodium hydroxide in the presence of the fish transic acid soap. This reaction was allowed to proceed for 1 hour, during which time the temperature rose to about 45 °. After ι hour the temperature was increased to about 135 ⁰ by supplying heat. Then, the heavy oil was added and the mixture heated with stirring to about 165 ^0th The oxidation inhibitor was then added and the entire mixture was cooled in the kettle while stirring.

The fat thus obtained was in a Gaulin homogenizer at different pressures the effect of shear stresses without simultaneous mixing subject. The effect of this treatment is given in Table V below.

Table V

pressure
kg / cm ²

Penetration, mm / io (25.0 ° WaIk-

Resting penetration

penetration '(6.0 shocks)

ο (not homogenized) 355 330

105 .... 199 222

¹⁰ 210 177 207

Example 6

Following the procedure of Example 5, a furfural fat of the following composition was prepared posed:

Components by weight

Furfural 10.0

Hydrogenated fish transacids 15.0

Sodium hydroxide 5.0

²⁰ oxidation inhibitor according to

Example 1 1.0

Mineral oil (coastal oil), viscosity

14.6 cSt / ₉ 8.9 ° 34.5

Mid-Continent Oil, Viscosity

² 5 i2cSt / ₉ 8.9 ^o : 34.5

Part One

A sample of this fat was processed in a Gaulin homogenizer at various pressures. The ASTM values of the samples are given in Table VI.

0
70
140
210
28O Pressure, Tabel kg / cm ² VI (not
sated). homogeneous Walk penetration, mm / 10 35 > 400
360
340
330
320 40

. Part 2

A second sample of this fat was passed through the Gaulin homogenizer several times at 210 and 280 kg / cm ^2. The values for the milled penetration are given in Table VII.

• Table VII

Passages Walkpenetra
210 kg / cm ² tion, mm / ίο
280 kg / cm ² O. > 400
330
310
295
280 > 400
320
270
270 I. 2 • 3 4 ···

This example shows that mixed soap fats made with furfural are also obtained according to the invention can be.

According to another feature of the invention provides one * first a mixture of a mixed soap, and a mineral oil of low VI forth heats it to over 250 ⁰ to the soap to completely dissolve, and the mixture is cooled so rapidly to a temperature between room temperature and 120 ° from the fact that the entire cooling time is only 2 to 10 hours. When the mixture has reached this temperature, another mineral oil is added whose VI is significantly higher than that of the base oil, whereupon the entire mixture is subjected to high shear rates without simultaneous mixing.

It is essential that the mineral oil used for blending have a high flash point and has a high V.I. Additives to improve the V. I. have no effect, since they crystallize on the soap particles, so that only the original V. I. of the base oil is effective. Such oils can be due to the insolubility of the melted soap cannot be used for the initial dispersion of the soap. It was too found that when producing the fats by the usual method of slow cooling of the Mass cannot add mineral oils of high V.I.

After the fat has been blended with the high VI oil, the mixture is ^{subjected to high shear rates of 10,000 to 500,000 seconds "1} or more. This is done in an apparatus in which there is no simultaneous mixing, as described above.

The original soap content before the addition of the mineral oil of high V. I! is 20 to 50%. at the slow cooling that was common in the past, a soap content in this range was necessary in order to reduce the desired ASTM penetration of 200 and 35omm / io to obtain. The addition of mineral oil with a high V.I. reduces the soap content of the finished product to 6 to 18%. The subsequent homogenization with high shear rate leads then to a product with a penetration of 200 to 350, preferably 275 to 300 mm / 10. ■ It is closed note that - apart from the considerable reduction in the cooling time - the desired Penetration achieved with a fraction of the soap content previously considered necessary.

The lubrication time of a rolling bearing lubricant was generally considered to be proportional to the amount of soap. It has now been found that greases the invention which to ¹ I ₃ included only about ^x \ _i this amount of soap, a known fats entirely equivalent lubrication duration have. This result, which can be attributed to the addition of an oil of high VI, could not be achieved with the previous method of slow cooling.

This feature of the invention is explained in more detail in the following examples.

Example 7

a) According to the manufacturing process described below a fat was produced with the following composition:

Components

Rapeseed oil

Sodium Petroleum Sulphonate in Solution

Sodium hydroxide ...:

Oxidation inhibitor according to

Example ι

Metal deactivator according to

Example ι

Mineral oil (from a coastal

Crude oil), viscosity

65 cSt / 37.8 ⁰ (VI 50)

Weight percent

22.0

o, 5
4.75

0.5

71.25

Manufacturing process: rapeseed oil, sodium petroleum sulfonate

(5o% solution in oil) and ¹ Z ₃ of the mineral oil were introduced into a directly heated grease kettle and heated to 65 ^0th Then, 40% aqueous sodium hydroxide solution was added and the mass heated with stirring to 150 ^0th After the dehydration, the rest Liehe mineral oil was added and heated to 260 the fat ^0th At this temperature, the heat supply was interrupted and cooled the fat to 93 ^0th During the cool down (at about 135 ^° ) the inhibitors were added. In 93 ⁰ the fat was removed and filtered. This packaging temperature of 93 ⁰ was reached in 20 to 22 hours.

b) 75 percent by weight of this fat was mixed with 25 percent by weight of the same mineral oil. The fat obtained in this way contained 18% soap compared to 24% in the case of the fat according to Example 1 and was too soft for the usual tests. The mass was forced through a Gaulin homogenizer at a pressure of 352 kg / cm ^2. As a result of this exposure to high shear rates without simultaneous mixing, the mass hardened to a solid fat.

The two above greases gave the following test values:

40 Table ^ / III To
use
the
Shear force Orig
liches
fat (b) 45 (a) Penetration, mm / 10 at 25 ° 285 Resting penetration 318 Walk penetration after 50 60 pushing 227 Drop point, ° C > 2Ö0 Oxidation test according to Norma-Hoffmann, O ₂ pressure drop around 320 55 0.3 kg / cm ² , hour 286 Lubrication duration (spindle test), 1605 hours I9OO

Example 8

75 percent by weight of a fat according to Example 7 (a) were with 25 percent by weight of an oil of high V. I. blended, which was obtained by phenol extraction of a mid-continent crude oil and had the following key figures:

Density (15.6 °) 0.879

Color value (Robinson) 9

Flash point, ⁰ C 246

Ignition point, 268 ° C

Viscosity cSt / 37.8 ⁰ 83.1

cSt / 98.9 ⁰ 8.7

V. 1 103.2

Melting point, ⁰ C - 9.4

This mixture was semi-liquid and did not harden to a fat consistency even when it was circulated through the Gaulin homogenizer ^{at 352 kg / cm 2.}

Example 9

a) A fat was produced according to Example 7 (a) with the only difference that the cooling from 260 to 93 ^{0 was} not slow but fast, namely within 8 to 10 hours.

b) 75% of this fat was mixed with 25% further base oil, for which purpose the low VI coastal oil distillate described in Example 7 was used. This mass was exposed to high shear rates without simultaneous mixing by forcing it through the Gaulin homogenizer five times ^{at 210 kg / cm 2.} The test results for the two greases were as follows:

Table IX

Orig
liches
fat Offcuts nes fat
after
use
the (a) Shear force (b) Penetration, mm / 10 at 25 ⁰ 275 Resting penetration 195 Walk penetration after 2OQ 60 pushing ^A. y 201 Walk penetration after 274 100,000 thrusts > 2Ö0 - Drop point, ⁰ C 241 Oxidation test according to Norma-Hoffmann, O ₂ - pressure drop around 275 0.3 kg / cm ² , hour 268 Lubrication duration (spindle I3I5 test), std 927

Example 10

50 percent by weight of the fat according to Example 9 (a) was combined with 50 percent by weight additional base oil. This gave a fat with a total soap content of 12%. This fat was also homogenized in a Gaulin homogenizer at 352 kg / cm ² .

The lubricating grease then had the following key figures:

ASTM penetration, mm / 10
at 25 ⁰

Resting penetration. 270

Walk penetration after 60 thrusts 276

Drop point, ⁰ C 204

Oxidation test according to Norma-Hoff-

man, hour 340

Lubrication time (spindle test), hours ... 769

Example 11

50 percent by weight of the fat according to Example 9 (a)

were mixed with 50% of the high V.I. oil described in Example 8. Through homogenization with a high shear rate without simultaneous thorough mixing in the Gaulin homogenizer was obtained an excellent, stable fat structure from the following. Key figures:

ASTM penetration mm / 10
at 25 ⁰

Resting penetration 299

Walk penetration after

60 thrust 300

Drop point, ⁰ C 196

Oxidation test according to Norma-Hoffmann, Std 220

Lubrication time (spindle test) hours 1365

The long lubrication time is particularly noteworthy as the grease only contained 12% soap.

The values given in Examples 7-11 are listed in the following table:

%
soap Cool-
speed winch
speed Table X homo
embarrassed walk
penetration
mm / io Lubrication duration
at the
Spindle test,
hours I315 example 24 slow VI des
Additional oil no 326 1900 927 7 (a) I8 slow _ Yes 311 1605 769 7 (b) i8 slow . low Yes (no fat structure) 1365 8th 24 fast high no 269 9 (a) i8 fast - Yes , 201 9 (b) 12th fast ■ low Yes 276 IO 12th fast low Yes 300 II high

These values and the drawing show the improvement that is achieved with the present process. Example ^ shows that a fat of good structure and good lubrication duration can be produced if a fat of 24 ° obtained by slow cooling according to the previous procedure is used / ₀

Soap content is diluted with an oil of low VI at 18 ° / ₀ soap and then homogenized. Example 8 shows that a high VI oil cannot be used for blending if cooled slowly. Examples 9 and 10 show that lower lubrication times are obtained when blending a rapidly chilled fat with a low VI oil. Example 11 shows the advantage of the procedure according to the invention: a fat with only 12% soap is produced by rapid cooling, and yet the lubrication time is considerably improved and the structure is within the desired penetration range. These values are shown graphically in FIG.

In the other examples, the fat base is used

a synthetic oil was added before the shear homogenization.

Example 12

The grease according to example (a) served as the basis. ' A synthetic lubricating oil was added to this, which consisted of a mixture of 65 ° / ₀ di-2-ethylhexyl sebacate and 35 ° / _{0 of} a mixed ester, the

by reacting 2 moles of the 2-ethylhexyl semi-

esters of adipic acid with 1 mole of a polyethylene glycol of a molecular weight of about 200 was obtained. About 50 percent by weight fat and Fifty percent by weight synthetic oil blend was mixed in a fat kettle. The soft, semi-liquid mass excreted clear oil on standing. The mass was passed through a Gaulin homogenizer sent and thickened. The fat then had the following key figures:

ASTM penetration, mm / 10
at 25 ⁰

Rest penetration 285

Walk penetration according to no

60 thrust 315

after 100,000 hits 385

Free alkalinity 0.16

Drop point, ° C -1S0

Oxidation test according to Norma-Hoffmann (duration of the decrease in oxygen pressure by

0.3 kg / cm ² ), Std 436

Lubrication duration (spindle test,

10,000 rev / min, 121 ^0), h. .. i860

Example 13

Using the fat base and procedure of Example 12, a second fat was made manufactured. This was a liquid phenyl silicone

(Dow Coming, Fluid 710) as a synthetic lubricating fluid used.

The properties of the fat after homogenization were the following: 5

Penetration, mm / 10 at 25 °

Rest penetration 290

Walk penetration after

60 bumps. 310

Walk penetration after

100,000 joints (perforated plate with 270 holes

to 3.175 mm) 420

Drop point, ⁰ C 223

Oxidation test according to Norma-Hoffmann (duration of the decrease in oxygen ^{pressure by 0.3 kg / cm 2} ), hours> 508

Example 14

This example corresponded to Example 13 with the proviso that a formal was used as the synthetic liquid which was prepared by reacting C ₈ -OxO-alcohol with formaldehyde. Properties of the fat:

ASTM penetration mm / 10
at 25 ⁰

Rest penetration 285

Walk penetration after

60 shocks 320

Walk penetration after
100,000 shocks 410

Drop point, ⁰ C 200

Oxidation test according to Norma-Hoffmann (duration of the decrease in oxygen pressure by
0.3 kg / cm ² ), Std 398

The fats according to Example 12 to 14 showed in an accelerated test for bleeding (.50 hours at 98.9 °), an oil separation of less than 3.0 ° / _0th

Claims (4)

Patent claims: 1. A process for the production of lubricating greases, characterized in that a lubricating grease obtained in a known manner from a mineral oil and a complex soap of a high molecular weight and a low molecular weight fatty acid with the further addition of a mineral or synthetic lubricating oil is subjected to a strong shearing action at a shear rate of 10 000 to 500 000 see- ¹ without simultaneous or subsequent mechanical mixing. 2. The method according to claim 1, characterized in that that the hot mixture of soap and oil before the further addition of oil quickly to a temperature below the solidification temperature of the Fat lying temperature cools. 3. The method according to claim 1 and 2, characterized in that there is a further oil that is used which has a higher viscosity index than that for initial mixing with the Soap owns oil used. 4. The method according to claim 1 to 3, characterized in that there is a complex soap Rapeseed oil soap is used. 1 sheet of drawings 609 544 6.