DE831577C - Lubricants, in particular based on mineral oil - Google Patents

Description

The present invention relates to high pressure lubricants which as additives phosphorus or sulfur and compounds thereof in mineral oil or a fatty oil base exhibit.

In many types of modern machines, very high pressures occur between the adjacent parts the moving metal surfaces. If such surfaces are not effectively and continuously lubricated there is rapid wear and tear and premature destruction. With the occurring Pressures are particularly at high speeds, high torques and high Temperatures often present conditions under which ordinary lubricants do not provide any protective properties Lubricating films can be maintained.

In such cases, thin layers of oil usually make the oil's lubricating film more chemical Compounds added or replaced, which are on and from the metal of the corresponding ao Form machine parts. Certain substances such as sulfur, chlorine and phosphorus combine in the process and the like, when added to lubricating oils and exposed to high temperatures, chemically with the Metal of the parts to be lubricated, producing films of microscopic thickness, which the Adhere the metal surface tenaciously and prevent metal from coming into contact with metal.

Lubricants of the type mentioned above consist of mixtures of a petroleum with a saponifiable one oil and contain sulfur, chlorine, phosphorus and the like as a high-pressure additive, either as free elements or as chemical compounds. The additives are usually and

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preferably at | normal Aid Temperatures che- ' mixed ineffective, but react with the metal surface when it is affected by the frictional heat exposed to high temperatures generated during power transmission by means of a gearbox will.

Up to now, either effective extreme pressure additives of the above film-forming ones have been used Type, which after a certain period of time resulted in rust formation on metals such as copper and steel, or additives which do not rust but are less effective.

The microscopically thin protective films that are applied to metal surfaces in the manner described above are formed, presumably consist of metal sulfides, metal chlorides, metal phosphides and the like when sulfur, chlorine, phosphorus and similar materials are applied to steel gears find, such as B. in differential gears for

ao motor vehicles, where at times very high total pressures occur, iron sulfides, chlorides, phosphides and the like formed. Similar connections will be formed with other (metals.

Many connections have already been established as high-

«5 printing additives! Are used, including inorganic substances such as phosphorus sulphides, e. B. P ₄ S ₃ , elemental phosphorus, arsenic, selenium, lead compounds, phosphorus oxides, various chlorides, etc. It is z. B. known that phosphorus sulfides can be dissolved or reacted in or with various fatty substances, such as fatty oils, fatty acids, sulphurized fatty oils, halogenated hydrocarbons and the like, in order to produce suitable high-pressure lubricants.

These compositions can then be used directly as extreme pressure lubricants or whatever is more common than concentrated additives in small quantities to lubricants based on mineral oil be admitted.

It is also known that organic phosphates, ζ. Ε. Tricresyl phosphate, either with or without other additives are used in fatty oils or fatty acids or in mineral oil or its mixtures can be good to the lubricants

♦ 5 properties to be given. In particular, it has been found that tricresyl phosphate as an antioxidant and is useful as a greasiness agent.

Although the various materials previously used, such as sulfur, phosphorus, chlorine and These are numerous compounds that are effective additives to extreme pressure lubricating oils, they are because of them corrosive properties can only be used to a limited extent if there is not a certain amount of corrosion who wants to accept lubricated parts.

It was z. B. found that the addition of a relatively large amount of phosphorus sesquisiulfide, P ₄ S ₃ , to a fatty oil containing sulfur, gives the lubricants excellent extreme pressure properties. However, the use of such relatively large amounts of phosphorus sulfide results in a lubricant which severely corrodes the metal. On the other hand, certain organic phosphates, such as. B.

Tricresyl phosphate and phosphites have a low corrosive effect, but are used as additives for high pressure loads not very effective, although they are useful in small amounts.

The invention aims to improve the extreme pressure properties of those mentioned above Lubricant with a simultaneous reduction or elimination of the corrosion effect. That will by an additive consisting of phosphorus sulfides and alkyl or aryl esters of phosphoric acids achieved. This combination of phosphorus-containing compounds has a surprisingly good effect. The phosphorus sulfide used is advantageously phosphorus sesquisulfide or phosphorus pentasulfide and as esters of phosphoric acids tricresyl phosphate or tributyl phosphite.

The maximum print quality of a lubricating oil seems to be more or less to a certain extent to be in direct proportion to the increase in the total phosphorus content, if the other conditions are the same. When inorganic phosphorus is used alone as an extreme pressure additive A point will soon be reached where the increase in the phosphorus content of the lubricant a harmful corrosive effect, which is reflected in the strong discoloration of copper and steel shows at higher temperatures. However, it has been found that with additional use of an organic phosphate or phosphite means the total phosphorus content of the lubricant Can be brought to a relatively high percentage without being cheap High pressure properties to show a corrosive effect. In other words, the combination an inorganic phosphorus compound such as phosphorus sulfide and an organic phosphorus compound, such as tricresyl phosphate or generally an aryl or alkyl phosphate or phosphite, gives excellent high pressure properties. This is especially true for certain inorganic ones Characteristic of phosphorus compounds is that they limit or cancel the corrosion effect at the same time. It appears that tricresyl phosphate and related organic compounds promote corrosion not particularly counteract. However, they allow an increase in the phosphorus content without the Corrosion effects! To increase significantly.

Such lubricants are of particular value in certain types of gearboxes, especially those that are heavily used, such. B. Differentials for truck axles.

The lubricants according to the invention can also contain other additives, such as. B. Means of Prevention of oxidation. Contain agents for lowering the pour point and the like. You can including various other organic or inorganic compounds or free elements Sulfur, chlorine, arsenic, selenium, tellurium, soaps, vegetable oils and / or other known additives contain. Of course, the various phosphorus sulfides and various aryl and Alkyl phosphates and phosphites within the scope of the invention. Besides tricresyl phosphate can also

the various lists of phosphoric and phosphorous acids as organic phosphorus compounds are used, with hydrogen atoms of the phosphoric and phosphorous acids be replaced by alkyl or aryl radicals to form esters or acidic esters.

The following information shows the excellent properties of lubricants according to Invention.

One extreme pressure additive for lubricating oil that has been found to be particularly useful consists of the following Composition:

Sperm Oil 89.9 ¹ Yo

Sulfur 5.8%

Phosphorsesquisulnd P ₄ S ₃ .. 0.5%

Tricresyl phosphate 3.8%

The following are examples of lubricants based on their extreme pressure properties and their corrosion effects have been tested.

example 1

1880 g natural winter spar oil 45 and 120 g sulfur were heated and stirred in a beaker,

% P ₄ S ₃ additions tab hurry I oil blends through kg / cm ²³ ) additive o, 5 % TCP *) Timken device
Width of scratches ² ) 2191 copper
Strip test ⁴ ) example
No. o, 5 0.0 OK load *) 1.35 3388 in order I. 0.4 4.0 14.8 1.35 2569 in order I. o, 4 0.0 22.9 1.5 2772 in order 2 0.5 4.0 19.3 1.65 2338 in order 2 o, 5 0.0 22.9 1.65 - 2877 in order 3 4.0 19.3 1.5 in order 3 22.9

the temperature is increased to 197 ⁰ and this temperature is _{maintained for 1/2} hours in order to allow complete reaction of the sulfur. This is followed by cooling to room temperature by letting it stand. The next day, the sulfurized product was heated to 99 ⁰ and 10 g Phosphorsesquisulnd, P ₄ S _3, was added and the temperature maintained with continuous and extensive stirring for 8 hours. Cooling was then carried out again as indicated above.

A portion of this additive was mixed with mineral oil in the proportion of Add 10 parts to 90 parts mineral oil to give a lubricant that meets the SAE 9 degree conditions. This was tested in the Timken device and became the Subject to copper and steel discoloration. A second part of the additive was made with tricresyl phosphate mixed in a ratio of 4 parts of tricresyl phosphate to 100 parts of additive and the resulting product mixed with 860 parts of mineral oil and tested as indicated above. the The results of this test are shown in Table I.

*) Tricresyl phosphate.

¹ ) kg on lever arm.

² ) unit = 0.04 cm.

^{: 1} ) Determined by the total pressure, measurement of the scratch width, etc. ') 24 hours at 150 ⁰ .

Example 2

2117.5 g No. ι lard oil, 125 g light mineral oil (45 SSU at 99 ⁰ ), 12.5 g sulfur monochloride and 185 g sulfur were mixed and placed in an autoclave. The autoclave was then flushed with hydrogen sulfide and heated to 165 to 172 ^{0 for} 8 hours while maintaining a gauge pressure of approximately 3.38 kg hydrogen sulfide and with constant stirring during the entire reaction period. The sulfurized product was then removed and cooled and finally returned along with 10 g of phosphorus sesquisulnd. A hydrogen sulfide pressure of 2.3 to 3.8 kg (manometer) was maintained as above and the temperature was kept at 104 to 10 8 ° for 5 hours. The product was then removed and cooled.

10 parts of the above-mentioned product and 90 parts of mineral oil were mixed to form a To produce lubricants that meet the requirements of SAE 90. The test took place as above. 0.4 part of tricresyl phosphate was added to the mixture and the test repeated. As shown in Table I, the addition of tricresyl phosphate improved the loading properties of the lubricant significantly without causing further discoloration of copper or steel.

Large scale manufacturing is described below:

B e i s ρ i e 1 3

ι d 600 g Naturwinterspermöl 45 were placed in a lined (ilas reaction vessel iao equipped with a high speed and a loose fitting lid. It was heated with stirring to 138 ^0th 1059.6 g of sulfur were added and heating -i continued, with the temperature in about V * hour rose to 197 ⁰ »». 5 the temperature was 1V2 hours at 197 ± 2 °

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and the mixture was then cooled by circulating water through a closed coil so that the temperature ^{dropped to 99 °} in 45 minutes. 88.7 g of phosphorus sesquisulphide were then added and the temperature kept under constant stirring for 8 hours at 99 to 104 ^0th The product was then cooled.

Then 10 parts of the above product with 0.4 parts of tricresyl phosphate and 89.6 parts of a mineral oil mixture mixed, which o, 5% of a pour point depressant agent contains and otherwise equal parts of propane dasphalted and dewaxed, central continental Steam cylinder oil and a SAE 20 grade phenol extracted mid continental Lubricant. Experiments with this mixture are shown in Table I. The composition of the The finished lubricant is roughly the following:

Sperm oil 9> 35 ° / °

Sulfur o.6o per cent

P ₄ S ₃ 0.050 / 0

Tricresyl phosphate 0.440%

SAE 90 base lubricant oil. 89.6 ° / o

The SAE grade basic gear oil consists of:

Means to reduce the

Pour point 0.22 ° / o

Steam cylinder oil 44.58 per cent

SAE 2 degree lubricating oil .... 44.78 ° / o

The agent for lowering the pour point is produced by condensation of chlorinated Paraffin with naphthalene.

In addition to the advantages mentioned, it was found that synergistic improvements through the addition of an inorganic compound can be achieved together with an organic compound that cannot be achieved by using one of the same. The following examples and information serve to explain the improved properties achieved.

Example 4

Natural winter spar oil 45 was ^{treated with 12% sulfur for 197 0} ιVa hours, whereupon 1 part mineral oil (steam cylinder oil) was added to 4 parts of the hot sulfurized product for quenching. The resulting product containing 9.5 ° / "sulfur containing approximately, was then treated with heating at 99 to 104 ⁰ for 8 hours with varying amounts of phosphorus sesquisulphide (the amounts are shown in Table II).

The finished additives were then mixed with the previously described S AE 90 grade mineral oil mixed in the ratio of 10 parts by weight of additive to 90 parts by weight of mineral oil. In some Tricresyl phosphate was added to the mixtures.

It can be seen that by using the two types of phosphorus compounds, a considerable amount of Improvement in loading capacity was achieved, without the lubricant for either Copper still gives corrosive properties to steel. The load-bearing skills can be in similarly can be increased by using a larger amount of phosphorus sulfide, however In this case, the product will corrode both copper and steel. The addition of a similar one The amount of phosphorus in the form of an organic phosphate alone gave a non-corrosive one Product with a very low load capacity.

Additive" % P Ί a b e 11 e II Scratches kg / cm ² Mineral oil blends Copper ⁴ ) all in all Timkerry device sample ² ) = 322 Metal corrosion in order _ 1 τ-) ο % TCP *) 0.0 OK load 12.0 = 326.2 Steel ³ ) in order 0/0 P ₄ S ₃ 0.0 0.2 14.0 2688 no blackening black 0.0 0.0 1.1 ⁼ i9.3 *> 7 ⁼ 275.8 no blackening in order o, 4 0.0 o, 7 = 22.9 14.0 2688 black in order 2.0 8.0 o, 6 22.9 i, 7 2772 no blackening in order 0.0 5, o 1.0 ⁼ i9.3 1.65 2366 no blackening in order o, 4 10.0 2.9 22.9 i, 9 no blackening o, 4 33.3 22.9 no blackening o, 4 22.9

Tricresyl phosphate.

less than the specified amount.

kg on the lever arm.

Unit = 0.04 cm.

24 hours at 150 ⁰ .

ι hour at 123 ⁰ (CRC-L-i6-445 method).

The following example shows the use of an alkyl phosphite.

Example 5
A mixture containing io ° / o of an additive prepared as in Example 3 in 90 ⁰ / o mineral oil, butyl phosphite was tested with and without addition of Trl · and gave the following results:

Table III

additions

0 / 0P ₄ S ₃

% Tributyl phosphite

Mineral oil blends

OK load kg

Timken device sample

Scratch width

kg / cm ²

o, 5
o, 5
o, 5

0.0
1.0
3.0

1.65
1.65
1.65

2338
2772
2772

In establishing the above figures a load level of 22.9 kg was found to be entirely satisfactory for the lubrication of truck differentials viewed, while lower loads were viewed as inadequate or at least doubtful. try with the Timken device were found to be in fairly good agreement with actual work trials in such cases.

In practice, extreme pressure lubricants can be prepared by adding various amounts of the additive mixture indicated in the first table to oils. The mixture consists of 89.9% sperm oil with 5.8% sulfur, P ₄ S ₃

»5 and tricresyl phosphate, which are essentially added in the specified amounts as required will. Usable lubricants usually consist of mineral and / or fatty oil bases, which contain 1 to 20% of the concentrated high-pressure additive. It is clear that different oils, fats, fatty oils, fatty acids etc can be used as lubricants that those organic and inorganic phosphorus compounds can be added in various amounts can.

A further example is a high-pressure oil or fat, which consists of approximately 90% of an oil or fat base material, which consists of mineral oil, vegetable or animal fats with or without soaps, and approximately 10% of a concentrated additive which contains the high-pressure mixture. The additive can contain 85 to about 95% of a fat body, such as. A fatty oil or a fatty acid, 3 to 8% sulfur, which is preferably cooked in the fatty body, 0.1 to 1 "/ 0P ₄ S ₃ and 0.2 to 20% tricresyl phosphate, which is introduced. Others Compounds such as pour point depressants, anti-oxidants, detergents

and the like can be added as known.

The additive itself can be manufactured and sold commercially, then in various ways Quantities of the mineral oils and other lubricants to be incorporated. Depending on the The additional compound can have the desired properties in amounts of an oily base 2 to 20% are added. For some special purposes, the additive can also can still be used in higher concentrations. Commercial considerations will be however, in general, the use of the additive to the specified percentage limits restrict.

Even if only sperm oil and lard oil have been mentioned, which have been found to be suitable as the base material for the additive, other animal and vegetable oils and the associated fatty acids can also be used. The fatty acids appear to be less suitable for truck transmissions, but they can be used for other purposes. Animal fats and oils are preferred. Likewise, instead of or in addition to P ₄ S _3, other binary phosphorus compounds, such as e.g. B. the other sulfides and oxides are suitable. Various inorganic phosphorus compounds can therefore be added or replaced. Similarly, for tricresyl phosphate, products such as triphenyl phosphates and other aryl phosphates and phosphites or methyl, ethyl or butyl phosphates and phosphites and analogous alkyl compounds and various other organic compounds of phosphoric acids and the like can be used. The percentage of these materials so used will vary, depending on their composition, solubility and overall effectiveness, however, they will be / are generally used in amounts of 0.1 to 20 ⁰ o, calculated on the finished lubricant. The aforementioned inorganics are preferably used in amounts from 0.1 to <2% in the additive and in amounts from about 0.01 to 0.2% in the finished lubricant. The percentages given in the description relate to the weight based on the total additive or lubricant.

Claims (13)

PATENT CLAIMS: 1. Lubricants, especially those based on mineral oil, characterized by a high-pressure additive from phosphorus sulfides and alkyl or aryl esters of phosphoric acids. 2. Lubricant according to claim 1, characterized by the addition of phosphorus sesquisulfide or phosphorus pentasulfide as phosphorus sulfide. 3. Lubricant according to claim 1 and 2, characterized by adding phosphates, especially tricresyl phosphate, as Phosphoric acid esters. 4. Lubricant according to claim 1 and 2, characterized by adding phosphites, especially tributyl phosphite, as 1 * 5 Phosphoric acid esters. 5 · Lubricant according to claim 1 to 4, characterized through a further content of fatty oils, preferably sulfurized fats oil as a high pressure additive. 6, lubricant according to claim 1 to 5, there- ■ characterized in that the amount of the oil base 85 to 95% of the total lubricant. 7. Lubricant according to claim 6, characterized by a content of 3 to 8% sulfur, 0.1 to 2% phosphorus sesquisulphide, 0.2 to 20% tricresyl phosphate and fatty oils as High pressure additive. 8. Lubricant according to claim 1, consisting of 80 to 99% of an oily base and ι up to 20% high pressure additive, a fatty oil, sulfur, a small percentage of phosphorus sesquisulfide and contains a small percentage of tricresyl phosphate. 9. Lubricant according to claim 1, characterized by a high pressure addition of 2 to 10% sulfur, 0.1 to 2% phosphorus sulfide and 0.2 to 20% tricresyl phosphate. 10. Lubricant according to claim 1, characterized by adding 0.1 to 2% phosphorus sulfide and 0.2 to 20% tricresyl phosphate at high pressure. 11. Lubricant according to claim 9 and 10, characterized in that the oil base is 95 to 85% mineral lubricating oil and the high-pressure additive 5 to 15%. 12. Lubricant according to claim 1, characterized characterized in that the high-pressure additive consists of a fatty base, 0.1 to 2% phosphorus sulphide and 0.2 to 20% aryl phosphates and aryl phosphites. 13. A method for the production of lubricants according to claim 1 to 12, characterized in that that first fatty oils are heated with sulfur, with a small amount Phosphorus sulfide and alkyl or aryl esters of a phosphoric acid and then with the main amount of the oil base material are mixed. I 3204 2.