DE1288719B - Lubricating oil - Google Patents

Description

It is known that EP additives are added to gear or toothed wheel lubricating oils, e.g. B. organic Sulfur compounds together with lead soaps and / or organic halogen compounds or phosphorus compounds.

It has now been found that a combination of a chlorinated hydrocarbon with a boiling point or a decomposition temperature not lower than 160 ° C, a dithiophosphate and a dialkyl phosphite, wherein the chlorine content of the lubricating oil mixture is 0.42 to 6.0 percent by weight and the proportions of dithiophosphate and dialkyl phosphite are such that in the lubricating oil mixture 0.048 to 1.0 weight percent sulfur, 0.036 to 0.3 weight percent phosphorus is particularly present has good extreme pressure properties and at the same time in hypoid gears under running conditions, at which high torques and low speeds occur, still good lubricating effect is.

Preferred lubricating oils according to this invention used to lubricate industrial gears should have a chlorine content of 0.42 to 3.0 percent by weight, a proportion calculated in this way of dithiophosphate on that from 0.048 to 0.3 percent by weight Sulfur, and a proportion of dialkyl phosphite such that from 0.036 to 0.1 percent by weight of phosphorus are contained in the lubricating oil mixture.

Where the lubricant formulation for use specifically as a hypoid gear lubricant is provided, it is preferred that the total chlorine content be from 2.5 to 6.0 percent by weight, the proportion of dithiophosphate is such that from 0.2 to 1.0 percent by weight of sulfur and the The proportion of dialkyl phosphite is such that from 0.1 to 0.3 percent by weight of phosphorus in the Lubricating oil mixture are included. The ratio of dithiophosphate is preferably one that from 0.3 to 0.7 percent by weight sulfur are created in the preparation.

Examples of chlorinated hydrocarbons are examples of dialkyl phosphites

Diethyl phosphite,

Diisopropyl phosphite,

Di-n-butyl phosphite,

Dioctyl phosphite,

Dilauyl phosphite.

These phosphites have the formula

R - CK

chlorinated paraffin wax,

chlorinated kerosene,

Hexachloroethane,

Benzene hexachloride,

chlorinated indene,

Dichlorodiphenyltrichloroethane (DDT) and chlorinated diphenyls.

Examples of dithiophosphates are

Zinc-di-n-pentyldithiophosphate, zinc-di- (1,3-dimethylbutyl) -dithiophosphate, Zinc isopropyl-1,3-dimethylbutyldithiophosphate,

Zinc isobutyl amyldithiophosphate, Zinc diamyldithiophosphate of mixed

Derived from amyl alcohols, zinc dialkyldithiophosphate from mixed

straight chain «! Coming from Ce-Cjo alcohols, zinc dialkyldithiophosphate from mixed

C3- Ce alcohols originating, nickel-dt- (2-ethylhexyl) -dithiophosphate, barium-dilauryldithiophosphate, chromium-dWp-octylphenylJ-dithiophosphate.

R ¹ -CT ^X H

wherein R and R ^{1 are} the same or different alkyl radicals. Preferably, R and R ¹ together have a total of 3 to 12 carbon atoms.

A paraffin wax with a chlorine content of 40 to 70% is preferred; is the dithiophosphate preferably a zinc dialkyldithiophosphate in which each alkyl group has from 3 to 12 carbon atoms and the dialkyl phosphite is preferably diisopropyl phosphite.

It will be understood that the formulation may contain conventional lubricating oil additives, for example Antioxidants or corrosion inhibitors, dispersants, detergents, pour point depressants and Viscosity index improver.

As an additional corrosion inhibitor, an oil-soluble, basic alkaline earth metal sulfonate, which with a weak acid, e.g. B. carbon dioxide, may be neutralized, added.

example 1

44.0% mineral oil A,
41.63% mineral oil B,
10.0% chlorinated paraffin wax with a

Content of about 42% chlorine, 2.5% zinc - isopropyl - 1,3 - dimethylbutyl-

dithiophosphate,
1.0% detergent D,
0.75% diisopropyl phosphite,

0.1% pour point depressant A.

Mineral oil A was a light, high viscosity oil with a viscosity of about 800 seconds Redwood I at 60 C.

Mineral Oil B was a solvent refined mineral oil of viscosity of about 150 seconds Redwood I at 60 C. The zinc dithiophosphate was in the form of an approximately 80% concentrate in oil, the phosphorus content of the concentrate being approximately 8%.

Detergent D was a phosphosulfurized polyisobutylene, reacted with a barium alkyl phenate and made basic in excess with a base ene Barium petroleum sulfonate. The pour point depressant A was a copolymer of mixed Fatty acid methacrylates.

This lubricating oil blend had the following viscosity properties:

6s

263.9 cSt at 37.8 C, «

17.2 cSi at 98.9 C,
Viscosity Index = 70/71.

The lubricating oil mixture contained

0.46% sulfur,

4.0'Vh chlorine,

0.23% zinc.

0.30% phosphorus.

The claimed lubricating oil had good results when exposed to a relatively heavy road load was subjected in the hypoid rear axle of a motor vehicle.

Example 2

39.5% mineral oil A,

46.15% mineral oil B,

10.0% chlorinated paraffin wax with a content of 42% chlorine,

2.5% zinc isobutyl amyldithiophosphate,

0.75% diisopropyl phosphite,

1.0% detergent D,

0.1% pour point depressant.

The zinc dithiophosphate was in the form of an approximately 80% concentrate in oil, the The phosphorus content of the concentrate was approximately 8.0%.

In order to examine the properties of these preparations, they were left in Example 1 in FIG Rear axle of a high-performance 2-liter sedan under high-speed conditions, together with Braking examinations take place, with these examinations in the Alps over a total distance of approximately 8000 km. Similar research was carried out on a similar Vehicle carried out using a hypoid transmission (mixture A) of the previously known type.

this mixture containing 5.5% extreme pressure additive with a content of approximately 16% sulfur, 3% Zn, 3% P and 16.5% Cl and 0.05% pour point depressants. This particular type of vehicle was made chosen because of largely the cooling airflow that normally acts on the rear axle because of the design of the axle unit was reduced by the execution of the axle unit, which partially in a recess to accommodate the

ίο Suspension or suspension unit installed became. As a result, the rear axle tends to run at temperatures higher than normal, with these were significantly increased under severe braking conditions by transferring them from the Disc brakes along the drive shaft 'to the axle housing.

The extreme pressure properties of both the prior art oil and the formulation of the present invention (Example 1) were tested before and after the test by testing on the known Four ball machine tested, which is similar to the one. which Boerlage in »Engineering«, July 13, 1933, vol. 136, p. 46. This apparatus includes four steel balls that are in the Are arranged in the form of a pyramid. The head ball was held in a clamping head with connected to a spindle that rotates at about 1500 revolutions per minute, and was pressed against the three ground balls, which are fixed in a stationary ball holder. the Balls were immersed in the oil to be tested. The examinations were usually 1 minute performed with series of different loads. The results of these studies are in the Table I given.

Table I Four-ball apparatus

mixture

Load (kg)

at the beginning

Seizure weld point

(kg)

Scar diameter (mm)
at load in kg of

150

200

250

300

350

Example 1 (before the examination) ...
Example 1 (after the investigation).
Mixture A (before the test).
Mixture A (after the investigation)

160/165

185/190

105/110

90/95 390
480
380
390

0.5

0.8
0.76

1.8
0.8
1.0
1.7

2.1
1.7
1.5
1.8

2.5
2.1
1.6
2.0

3.0
2.1
1.8
2.2

The surprising result was that the lubricating oil was more effective after the test than before, especially with regard to the load at the beginning of pressing.

To demonstrate the unexpected synergistic effect in the lubricating oils according to the invention The following five mixtures were also tested as described above:

1. 90% base fluid,

10% chlorinated paraffin wax containing about 42% chlorine.

2. 97.5% base fluid,

2.5% zinc isopropyl 1,3-dimethylbutyldithiophosphate.

3. 99.25 «/» basic liquid,

0.75% diisopropyl phosphite.

4.87.5% base fluid,

Containing 10% chlorinated paraffin wax

about 42% chlorine,

2.5% zinc isopropyl-1,3-dimethylbutyldithiophosphate.

5. 86.75% base fluid,

Containing 10% chlorinated paraffin wax

about 42% chlorine,
2.5% zinc isopropyl-1,3-dimethylbutyl-

dithiophosphate,
0.75% diisopropyl phosphite.

The basic liquid consisted of the following components in the following proportions:

68.9% mineral oils,

30.0% mineral oil B,
1.0% detergentD,
0.1% pour point lower A.

Mineral Oil C was a refined, "light-colored" material solvent with a viscosity of about 600 redwood 1 seconds. The other components of the base liquid were the same as explained in Example 1. The test results are given in Table II below:

at the Seizure Tabel 1 II mixture
3 4th 5 100/105
280 110/115
200 95/100 j
540 155/160
560 Starting load
(kg) 115/120
380 Welding point (kg) ...

The table clearly shows the superior effectiveness of the mixture 5 according to the invention, which could not have been foreseen.

In addition, the following four mixtures were investigated, which consist of the same base liquid, as described above, and various additives of the combination according to the invention exist, individually (mixtures 1 to 3) and together (mixture 4).

Table III

1. 86.75 ° ₍₎ base liquid

13.25 °, () chlorinated paraffin wax containing 40 ° «chlorine ....

2. 86.75 °, ι base liquid

13.25 ¹ Vo of zinc isopropyl-1,3-dimethylbutyldithiopho.sphat

3. 86.75 ° ο base liquid

13.25 ", ii diisopropyl phosphite

4. 86.75% base liquid

13.25 ° o Additive combination according to the present invention ...

Previous results

Starting load when seizing

(kg)

45
125
155

160
160

Welding point

300
490

550

510
560

The fourth mixture examined above corresponds to mixture 5, Table II. Which was examined again became.

Although the high proportion of diisopropyl phosphite in mixture 3 appears to be a preparation at first glance comparable / u that appears to be the three-component preparation of the present invention, however, mixture 3 was in view of the limited solubility of diisopropyl phosphite in Mineral oil cloudy. Such a non-homogeneous mixture is for use as a lubricant worthless, as it can separate itself again in operation. Above that, such a mixture would be like that commercially unacceptable to the market as the public generally has such non-homogeneous mixtures is suspicious of. Another reason is that diisopropyl phosphite is extremely expensive and such large quantities are therefore not recommended by the person skilled in the art would be.

Although the above experiment showed that the lubricating oil could work under severe conditions. High speed work Including with brakes, was effective, the impression was given that better-controlled Conditions can be obtained by performing studies on a test track could.

Accordingly, another model of the same 65 was made Vehicle «with an already retracted rear axle and with different levels of drawbar load (the carriage ': no force gauge with a drawbar) and low speed in the Alps.

Four sets of experiments were planned to maintain an oil mass temperature of approximately 150 C. These are given in Table IV.

Table IV
Test sequences for the dynamometer

Load on the pull bar U-. (kg) 1 318 T 363 3 45.4 4th 997

Motor vehicle I motor vehicle gear ' speed 1km st) 2 64 2! 56 3 56 3 64

The examinations were carried out in the following order:

Fresh Mixture A - Sequences 1, 3 and 4; Allow to cool to ambient temperature (approx. Vk hours), then run at normal road speed for 10 minutes.

2. Mixture A used - sequence 1, 3 and 4.

3. Fresh preparation of example 2 - sequence 1 and 2.

4. Preparation used from Example 2 - Sequence 1 and 2.

7 8

The results of these tests are given in Table V.

Table V

relationship
the increase 25 minutes Temperature (° C) reached after 25 minutes 15 minutes 10 mins oer
temperature episode 1 Episode 2 Episode 3 Episode 4 per minute 178 no load - 156 160 CC) 162 5V4 minutes 155 158 Mixture A (before the test) ... . 4.2 136 162 150 - - Mixture A (after the test) .. 3.6 130 142 141 Example 2 (before the examination) .... 2.3 122 Example 2 (after the examination) ... 2.5 115

All operations were carried out under similar climatic conditions in dry, warm weather and light winds carried out.

These results clearly showed that the preparation of the present invention allowed the Running the rear axle at a much lower temperature than the hypoid gear oil after that State of the art. In addition, the load that had to be applied to the oil was a temperature of to reach about 150 C, much higher than in the case of the gear oil according to the level of Technology. This is shown by the fact that Sequence 2 was much heavier than either Sequence 3 or 4, actually so severe that undue overload on the dynamometer that Machine of the carriage and the components not connected to the axle. Four-ball examinations were again at the mixture A carried out before and after the investigation and the preparation of example 2, how these were used in the dynamometer tests above, and here again the improved extreme pressure properties of the preparation according to the present invention after use The results of these tests are shown in Table VI.

Li.Λ ! Kg! at
beginning
Seizure Table Vi ! 50 ■ coloring u
200 rchmess
220 ; r (mm)
250 The burden
300 in kg
350 - 120/130 Welding
Point
(kg! 1.20 1.56 1.61 2.17 1
400 Mixture A
(before the examination) 120/135 400 1.34 1.64 1.71 1.78 2.13 _ Mixture A
{after the examination) 160/165 310 0.58 1.73 1.98 2.25 3.52 preparation
(before the examination) 195/200 350 ^ _ 0.89 1.02 1.62 2.02 2.34 . , Example 2
(after the examination) 400 2.69

To evaluate the oxidation stability of a typical preparation according to the present invention Example 2 with a mixture (mixture B) according to the U.S. Military Specification MJL-L-21Q5 B compared which the same additive addition like mixture A, but in a higher concentration (9.5%). With this one Test, described in Federal Test Std.-191, method 2504-T, runs a small housing bearing for 50 hours at a controlled temperature with the bearings lubricated by the oil under test will. At the end of the set time, the oil will increase in viscosity and the Insoluble matter content investigated.

The experimental conditions were as follows:

Temperature 157.2 ± 0.6 ⁰ C,
Load on gearbox caused by driving an electric generator with an output power of 128 watts,

Air flow through the lubricant 1.111 per Hour.

Just like the steel gears, a copper catalyst was used incorporated into the system to determine the copper activity of the lubricant.

The results obtained from the two oils are given below.

Table VII Example 2

Mixture B

The specification requires

Viscosity (cSt) at 98.9 ° C
Beginning

end

Increase (%)

21.49 28.61
33.1

17.29
30.19

74.6

100 ° / o maximum 909506/1473

continuation

Example 2

Mixture B The specification requires 7.2 no 6.09 3% maximum 2.72 2% maximum 2.21 report 0.0508 report 0.0127 report

Acid number of the oil after the test

Pentane-insoluble substances (%)

Benzene-insoluble substances (%)

• Loss of catalyst weight (g)

.Gear back deflection (mm)

Bearing cleanliness (mm)

The results indicated that the performance of Example B was a significant improvement over Mixture B, a typical MIL-L-2105 lubricant, depicted.

Claims (1)

Claim: Lubricating oil containing a combination of three known lubricating oil additives and optionally other common additives, characterized in that it is a combination 3.06 3.39 2.07 0.44 0.0127 0.0127 nation of a chlorinated hydrocarbon having a boiling point or a decomposition temperature of not lower than 160 ⁰ C, a dithiophosphate and a dialkyl phosphite, the · chlorine content of the lubricating oil composition is from 0.42 to 6.0 weight percent, and the proportions of dithiophosphate and dialkyl phosphite are so dimensioned that the lubricating oil mixture contains 0.048 to 1.0 weight percent sulfur, 0.036 to 0.3 weight percent phosphorus.