JPH0768536B2 - Improved mist lubricant composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improved mist lubrication methods and compositions having good lubricity and mist forming properties which are obtained using a specific synthetic ester and a polyisobutylene polymer mixture having different molecular weights.

The synthetic ester used in the composition is a polyol ester,
Trimellitate ester and polymerized fatty acid ester.

Automatic lubrication using oil mists is well known and is recognized in some applications as the most effective and economical means of providing a lubricant adjustment amount at the lubrication point. Oil mist lubrication is particularly convenient when the points or areas to be lubricated are not easily and safely accessible.

Oil mist is widely used for lubrication of equipment used for steel processing work. It is considered to be a particularly effective form of lubrication for high temperature roll mill bearings, resulting in more effective utilization of lubricant and longer bearing life. Extended bearing life is generally believed to be the result of (1) a more even distribution of lubricant, (2) low bearing temperature and (3) contaminant rejection. The advantages of (2) and (3) are a direct result of the airflow associated with bearing mist applications.

In addition to having suitable lubricity, the oil must have suitable mist properties to be suitable for mist lubrication. Polybutene,
Polyisobutylene, polyacrylate and ethylene-
High molecular weight polymers such as propylene copolymers are added to the base oil to produce normal mist properties. TD is a general discussion on the effect of polymer additives on mist properties.
By Newingham Lubrication Engineering, 33
(3), 128-132 (1977).

U.S. Pat. No. 3,510,425 discloses a mist lubrication method which utilizes a camel oil composition containing 0.05 to 3.5 wt% polyester which is convenient as a mist oil. Convenient polyesters for mist oil compositions have a number average molecular weight of 80,000 to 150,000 and are derived from esters of acrylic or methacrylic acid with C _12-12 alkyl monohydric alcohols.

Mist lubricants based on coconut oil and their usage are described in US Pat. No. 3,853.
It was also announced in 5,135. The polymeric additive used in the method of U.S. Pat. No. 3,855,135 has a viscosity average molecular weight of 10,000 to 2,000,000 and is selected from polystyrene and mixtures of polystyrene with polyacrylates or polybutenes. To obtain proper mist lubricity, 0.01 to 2% by weight of polymer additive is added to the oil.

A mist lubrication method utilizing a lubricating oil containing a minimum amount of polymer additives having a number average molecular weight of at least 10,000 has also been disclosed in British Patent Specification 1,099,450. Polymer additives are particularly low shear stability products commonly used as VI modifiers in motor oils. Number average molecular weight of at least 100,
Copolymers of vinyl acetate with 000, alkyl fumarate ester and N-vinylpyrrolidone are said to be particularly convenient additives for this process.

U.S. Pat. No. 3,805,918 discloses a method for reducing undesired lost mist in mist oil lubrication to a low level by using a mist oil containing 0.001-2% by weight of an oil-soluble polyolefin mist inhibitor. Oil-soluble copolymers of ethylene and C _3-12 monoolefins with an average molecular weight of 5,000 or more are particularly useful additives. In addition to petroleum derivative-based oils, hydrocarbon-based oils such as alkyl, aryl and alkaryl phosphate esters, alkylbenzenes, polyoxyalkylene esters or glycols, orthosilicates and siloxanes are also used in this method. It has been shown to be convenient for

Butene polymers are also used in other lubricant composition formulations. For example, U.S. Pat. No. 3,098,042 discloses lubricating liquids or greases derived from either oil or synthetic oils containing butene-1 polymers having a molecular weight of 10,000 to 20,000. Various synthetic esters derived from mono- and / or dibasic acids and monofunctional or polyfunctional alcohols have been described as convenient for the preparation of these lubricants. Polybutene-1 is about 0.
It can be used in an amount of 5 to 12% by weight. Conventional grease thickeners such as salts and fatty acid soaps may also be included in the composition. Synthetic lubricants containing 10 to 95% diester and 90 to 5% butene polymer with good shear stability and cold temperature fluidity are described in U.S. Pat. No. 3,860,522. Diesters are obtained from branched chain dicarboxylic acids having 16 to 22 carbon atoms and aliphatic alcohols containing less than 6 carbon atoms. Butene polymers have a molecular weight of about 1,200 to 4,500. However, none of the above compositions are used for oil mist applications.

It would be very convenient if there was a method that provided good lubrication and misting. It would be even more convenient to have an oil mist lubricant that has improved lubrication and mist properties obtained from readily obtainable synthetic ester feedstocks.

Applicants have now discovered an improved process using an improved mist lubricant consisting of a polyisobutylene polymer mixture having a molecular weight different from that of a relatively high viscosity synthetic ester. The synthetic esters used are polyol esters, trimellitate esters and polymerized fatty acid esters having a viscosity of 40 ° C. of 15 to 300 centistokes. Be sure to use two polyisobutylene polymers. That is, one has an average molecular weight of 4,000 to 10,000 and the other has an average molecular weight of 25,000 to 300,000.

The improved method and improved mist lubricant composition of the present invention can effectively produce suitable mists over a wide range of operating temperatures. This feature allows for significant productivity gains.
Further, the use of the method and composition of the present invention provides a significant improvement in bearing life (15 to 20%) over petroleum-based mist oil.

The present invention provides improved lubricant compositions. This composition comprises (1) (a) 2 to 8 hydroxyl groups and 3 to 3
Aliphatic polyols having 12 carbon atoms and 5 to 5 carbon atoms
Aliphatic monocarboxylic acid having 20 (may be a mixture thereof)
(B) trimellitic acid or its anhydride and a trimellitic acid ester formed from an aliphatic alcohol having 8 to 16 carbon atoms; and (c) 75% or more C ₃₆ dimer acid. 45 to 95 parts by weight of a synthetic ester selected from the group consisting of a polymerized fatty acid containing C _1-13 and a polymerized fatty acid ester produced from a C _1-13 monofunctional alcohol, (2) an average molecular weight of 4,000 to 10,000 based on 100% of the polymer. 8 to 40 parts by weight of polyisobutylene; and (3) polymer 100%, average molecular weight 25,00
A composition comprising 0.1 to 1 part by weight of polyisobutylene having 0 to 300,000 and having a viscosity of 125 to 750 centistokes at 40 ° C.

The present invention further provides a lubrication method. About 10 lubricants
In this method, the method is improved by squeezing and transferring to a metal surface to be lubricated as a mist in the air at a pressure of 100 psig to coalesce into larger droplets and depositing on the metal surface to form a lubricious film thereon. It comprises using an inventive composition.

A particularly convenient oil mist composition has a viscosity of 175 to 550 centistokes at 40 ° C, 12 to 30 parts by weight of synthetic ester, 12 to 30 parts by weight of polyisobutylene with a weight average molecular weight of 4,500 to 8,500 and an average molecular weight of 50,000 to 200. ,
Polyisobutylene with 000 0.25 to 0.85 parts by weight. Small amounts of petroleum diluents and effective amounts of conventional lubricant additives may be added.

The improved mist lubricant composition of the present invention comprises a relatively high viscosity specialty synthetic ester as a relatively low molecular weight first polyisobutylene polymer and a second polyisobutylene polymer having a significantly higher average molecular weight than the first polyisobutylene. It can be mixed. Ester and polyisobutylene polymer are used in a specific ratio in order to achieve a good balance between mist characteristics and lubricity. Although the lubricant composition of the present invention can be used in conventional mist lubrication systems known in the art, it has particular advantages in high temperature strip mill roll bearing lubrication.

Mist lubrication systems including mist lubrication and its working conditions are well known. Many mist lubrication systems are well documented in the literature. Generally, mist lubrication includes generation of oil mist and is sometimes referred to as microfog or aerosol, and the mist in air or an inert gas is squeezed and transferred to a point where lubrication is required. The mist passes through a reclassifier (Olihus), which coalesces or agglomerates tiny oil droplets into large droplets before heading over the lubricated object.

The mist generator is used to form oil mist. Generally, this generator consists of a lubricant container, which is connected to the bench lily by means of an oil pumping (sign-on) pipe. When compressed gas, ordinary air, passes through the bench lily, the lubricant is withdrawn from the container and intimately mixed with air to form droplets. The air-droplet mixture contacts a generator with a regulating plate, which condenses the large drops back into the oil container. Small oil droplets, typically 3 microns or less, remain compressed in the air and are squeezed to the lubrication point by a manifold distribution tube.

The amount and nature of the mist produced can change with changes in air temperature and pressure (velocity). Pressures between 10 psig are used. The air temperature is generally 100-225 ° F. It is especially preferred that the air temperature be maintained at 125-200 ° F.

The distribution system is designed to deliver the oil and air dispersion to the point of lubrication with the least amount of agglomeration. Therefore, the tube length must not be too long and care must be taken in its design. For example, the bends in the pipe should be minimized and sharp bends should be avoided. Also, there should be no low points such as aggregates clogging the tubes. The distribution tube is generally preferably inclined towards either the generator or the lubrication point to avoid agglomeration. Provide an outlet if necessary. The auxiliary pipe generally comes from the top of the main distribution pipe. In general, the design requirements for the auxiliary pipe are the same as for the main manifold or header.

The oil-air dispersion passes through a reclassifier (Olihus) and small oil droplets are converted into large droplets (aggregate) to increase the speed of the oil-air dispersion. This ensures maximum wetting of the lubricated surface. The size and type of reclassifier will depend on the particular application and oil-air dispersion characteristics.

The amount of lubricant that is treated, that is, becomes a mist, is referred to as the "production amount". The amount produced is expressed in unit weight or volume per unit time, eg g / h. Then, it is further divided into three components: (a) mid-aggregated content, (b) reclassified oil, and (c) lost mist. The agglomerated amount is the amount of mist agglomerated in the tube and does not reach the reclassifier. The mist condensed in the distribution pipe is returned to the mist generator for reuse. Reclassified oil is the actual amount of lubricant applied to the surface being lubricated. Mists that do not apply to the lubricated surface but escape to the atmosphere are called dissipated mists or dissipated fugues. The amount produced is (a) + (b)
Since it is equal to + (c), the dissipated mist is determined from the difference between the sum of (a) and (b) and the production amount. Premature agglomerates, reclassified oils, and dissipated mist are often reported or expressed as percentages of production.

It is clear that even if a high production amount is obtained, the distribution of the mist component cannot be used or the uneconomical specific mist oil system can be used. For example, tube aggregates (halfway aggregates)
Or, each significant amount of dissipated mist wastes lubricant at the lubrication point. It is especially troublesome because the lost mist is a loss lubricant. Not only does this pose a dilemma from an economic point of view, but it can also impede health and safety in the future. Therefore, the distribution of mist components (a), (b) and (c) must be taken into consideration together with the production amount in the development of an appropriate mist lubrication system and selection of mist oil of this system.

Therefore, in order to have an appropriate oil mist system, it is necessary to provide an appropriate lubrication system. This requires that the mist oil has good mist properties as well as good lubricity, oxidative stability, antiwear and extreme pressure properties, rust and corrosion resistance and other properties possible depending on the particular application. The lubricant should also be essentially free of undesirable waxes. The wax is generated in the reclassifier head to block or plug it.
Either way, the supply of lubricant to the lubrication point will be insufficient, and the life of the bearing will be shortened.

The lubricant must also exhibit good wetting and spreading on the surface (s) to which it is applied. One of the problems often encountered in mist lubrication of large bearings such as those used in strip mills is the lack of uniform lubricant distribution over the entire bearing and roll neck. Lack of this proper lubricant film results in excessive local wear and premature bearing failure. A "dry neck" or under-lubricated area on the roll neck is often observed during the disassembly of mist oil lubricated roll mill bearings. Mist oil lubricants and lubrication methods that provide uniform coatings on all bearings and roll necks, respectively, significantly extend bearing life and reduce operating costs.

The mist oil composition and the lubrication method of the present invention easily produce an effective amount of oil mist, and also have a good oil mist distribution, that is, a small amount of dissipated mist and premature agglomeration. It also enables high yields over a wide range of operating temperatures and pressures and minimizes annoying wax deposits, which in most cases is completely eliminated.
Also, quite unexpectedly, the mist oil composition of the present invention has improved wetting and spreading so that a uniform continuous film of lubricant is formed on the bearing and roll neck when the mist is used in a roll mill bearing.

Said modification has a different average molecular weight than synthetic ester 2
Obtained using the mist lubricant composition and method of the present invention using a polyisobutylene polymer mixture. The synthetic ester used in the present invention is a relatively high viscosity polyol ester, trimellitate ester or polymerized fatty acid ester. These esters have viscosities of 40 ° C. of 25 to 300 centistokes. A particularly convenient mist oil composition is obtained when the synthetic ester has a viscosity at 40 ° C. of 50 to 250 centistokes.

Polyol esters which can be used are derived from aliphatic polyols having 2 to 12 carbon atoms and 5 to 8 hydroxyl groups. Polyols generally have 5 to 8 carbon atoms and 2 to 4 hydroxyl groups. Examples of aliphatic polyols of the above form are neopentyl glycol, 2,2-dimethyl-3
-Hydroxypropyl-2,2'-dimethyl-3-hydroxypropionate, 2,2,4-trimethyl-1,5-pentanediol, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, dipentaerythritol, Examples include tripentaerythritol. Industrial pentaerythritol can also be used, containing varying proportions of mono-, di-, tri- and higher pentaerythritol. Neopentyl glycol, trimethylolpropane and trimethylolethane are particularly convenient. The polyol is an aliphatic monocarboxylic acid or 5 carbon atoms.
Reacts partially or completely with a mixture of aliphatic monocarboxylic acids with .about.20. The C _5-20 aliphatic monocarboxylic acid may be linear or branched, and may have a saturated or unsaturated group. These are obtained from natural fats or oils or those synthesized by oxo, kozo or other known reactions. Examples of aliphatic monocarboxylic acids are valeric acid, isovaleric acid, caprylic acid, capric acid, lauric acid,
There are myristic acid, palmitic acid, isopalmitic acid, stearic acid, isostearic acid, ricinoleic acid, oleic acid, linoleic acid and mixtures thereof. The mixed acid is derived from coconut oil, linoleic acid and mixtures thereof. Coconut oil, lard oil, tall oil, safflower oil, corn oil, beef tallow, soybean oil, palm oil, castor oil, rapeseed oil and the like can also be used. Polyol esters such as trimethylolpropane trioleate and trimethylolpropane triisoisostearate obtained from the esterification of trimethylolpropane with C _12-18 aliphatic monocarboxylic acids or mixtures thereof are mist oil compositions of the present invention. Especially convenient for manufacturing. Polyol ester is generally 15
It has a smaller acid number and a hydroxyl number less than 100. The acid value and hydroxyl value of ordinary polyol ester are 8 or less and 25 or less, respectively.

A convenient trimellitate ester is obtained from trimellitic acid or trimellitic anhydride and an aliphatic monofunctional alcohol having 8 to 16 carbon atoms. Trimellitic acid and trimellitic anhydride are, of course, well-known chemical products as their production methods are known. The aliphatic alcohol may be a linear or branched primary, secondary or tertiary alcohol. Examples of alcohol include n-octyl alcohol, capryl alcohol, isooctanol, 2-ethylhexanol,
Decyl alcohol, isotridecyl and isodecyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol and the like. A particularly convenient trimellitate ester is obtained from C _10-13 fatty alcohols or mixtures thereof. Isodecyl trimellitate, isotridecyl trimellitate and their mixtures, namely isodecyl / isotridecyl trimellitate, are particularly convenient esters of this form. The acid value of this ester is generally 15 or less, preferably 5 or less. The hydroxyl value is generally 10 or less, preferably 3 or less.

Polymerized fatty acid ester contains 75% or more C ₃₆ dimer acid
Obtained from polymerized fatty acids containing C _1-13 monofunctional alcohols. Polymerized fatty acids are known for their production and can be obtained by the polymerization of oleic unsaturated monocalebonic acid having about 16 to 20 carbon atoms such as oleic acid and linoleic acid. The process generally involves the treatment of unsaturated fatty acids with acid catalysts such as HF, BR ₃ etc .: thermal polymerization of unsaturated fatty acids with or without the presence of treated or untreated clay catalysts: Includes peroxide treatment. References for producing polymerized fatty acids include US Pat. Nos. 2,793,219 and 2,955,121. Polymerized fatty acids from unsaturated fatty acid polymerization consist primarily of dimer and trimer acids. However, small amounts of higher acids and unreacted monomers are also present in the mixture.

C ₃₆ polymerized fatty acids are obtained by polymerizing C ₁₈ unsaturated monocarboxylic acids such as oleic acid, linoleic acid or mixtures thereof (tall oil fatty acids). These polymerized fatty acid products have C ₃₆ dimer acid and C ₅₄ trimer acid as the main components.

Good results have been obtained with this form of acid, which contains 75% by weight or more of C ₃₆ dimer acid and the balance is essentially C ₅₄ trimer acid. Polymerized fatty acids with a high dimer content of higher polymeric acids and unreacted unsaturated monocarboxylic acids can be obtained by molecular distillation or other high efficiency distillation methods.
The polymerized fatty acid may be hydrogenated before use. This type of polymerized fatty acid product is commercially available under the trade name of Mpol dimer acid.

Convenient alcohols for the production of polymerized fatty acid esters are aliphatic branched or straight-chain monofunctional alcohols having 1 to 13 carbon atoms. Representative monoalcohols include isobutyl alcohol, isoamyl alcohol, neopentyl alcohol, n-hexyl alcohol, n-octyl alcohol, 2-ethylhexanol, decyl alcohol, isodecyl alcohol, isotridecyl alcohol, lauryl alcohol and the like. A small amount of polyfunctional alcohol with monofunctional alcohol (s), such as ethylene glycol, 1,2- or 1,3-propanediol, 1,3
-, 1,4- or 2,3-butanediol, 2,2,4-trimethyl-1,5-pentanediol, 1,6-hesisandiol,
Neopentyl glycol, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol, tripentaerythritol and the like may be used. A particularly convenient polymerized fatty acid ester is a polymerized fatty acid containing 85% or more of C ₃₆ dimer acid and C
_{8-10 Obtained from} aliphatic monoalcohol. Diisodecyl dimerate and di-2-ethylhexyl dimerate are particularly preferred. Polymerized fatty acid ester is generally 100 or less, usually 1
It has an acid value of 0 or less. The hydroxyl value is generally 10 or less, preferably 3 or less.

In order to obtain the improved mist oil composition of the present invention, it is necessary to use a mixture of isobutylene polymers having different average molecular weights together with the synthetic ester as defined above. Generally, 2 polyisobutylene is used, the first is low molecular weight polyisobutylene and has an average molecular weight of 4,000 to 10,000. The second is high molecular weight polyisobutylene and has an average molecular weight of 25,000 to 300,000. As used herein, the molecular weight is the weight average molecular weight (w).
Say. There are small amounts of other butylene polymers that do not fall within the above molecular weight range. A particularly convenient mist oil composition of the present invention has a low molecular weight polyisobutylene having an average molecular weight of 4,500 to 8,500 and a high molecular weight polyisobutylene of 50,000 to 200,
Obtained when having an average molecular weight of 000.

The isobutylene polymer essentially has the formula: (In the formula, x is an integer representing the number of repeating units). It is known that the above-mentioned polymers are widely used in the industrial field. These are usually obtained by polymerizing an isobutylene feedstock containing small amounts of butene-1 and / or butene-2. As used herein, polyisobutylene or isobutylene polymer includes polymers of the type described above.

Isobutylene polymers are obtained by commonly known polymerization methods. The polymerization reaction is carried out in an inert hydrocarbon, in which case a polymer solution containing about 30-80% polyisobutylene is obtained. If desired, a diluent may be added to the polymer upon completion of the polymerization reaction. The isobutylene polymer solution can be used in the improved mist oil formulation of the present invention. This facilitates the processing and mixing of polyisobutylene and synthetic ester. All parts and percentages herein regarding polyisobutylene are polymers.
Calculated on a 100% basis. The inert hydrocarbons present in the mist oil composition as a result of using the isobutylene polymer solution do not impair the misting and lubricity of the overall product.

In the composition and method of the present invention, 45 to 95 parts by weight of synthetic ester is 8 to 40 parts by weight of low molecular weight polyisobutylene based on 100% of polymer and 0.1 to 1 part by weight of high molecular weight of 100% of polymer. Mixed with polyisobutylene. A more preferred mist oil composition is 55 to 85 parts by weight of synthetic ester, 12
To 30 parts by weight of low molecular weight polyisobutylene and 0.25 to 0.85 parts by weight of high molecular weight polyisobutylene.

63-78 are particularly convenient mist oil lubricants with ISO grades 220, 320 and 460 that are widely used in industry for high temperature strip mill bearing lubrication and have excellent mist and lubrication properties.
Parts of di-2-ethylhexyl dimerate (viscosity of 91 centistokes at 40 ° C, viscosity index of 155; crystallization point of -50 ° F; acid value <
3; Hydroxyl acid 2), 14 to 28 parts of polyisobutylene (average molecular weight of about 7,500-7,600) and 0.33 to 0.66 parts of polyisobutylene (average molecular weight of about 89,000-90,000). The compositions and typical properties of 220, 320 and 460 ISO grade products formulated with appropriate amounts of additives are as follows.

The final mist oil formulation usually contains one or more additives. Typical additives that are commonly used include antioxidants, antiwear / EP agents, rust and corrosion inhibitors, metal deactivators, foam inhibitors, and emulsification inhibitors. Many of these have overlapping or multiple functions. For example, some additives provide both antiwear and severe pressure resistance or have the function of both metal deactivators and corrosion inhibitors. These additives in total do not exceed 8% of the formulation, usually not more than 5%.

Antioxidants that can be used include 4,4'-methylenebis (2,6-
Di-t-butylphenol), 2,6-di-t-butyl-
A phenolic antioxidant obtained from t-butylphenol such as N, N-dimethylamino-p-cresol and thiodiethylenebis (3,5-di-t-butyl-4-hydroxy) hydrocinnamate; Arylamines including N, N-diphenylphenylenediamine; diphenylamines such as p-octyldiphenylamine, p, p'-dioctyldiphenylamine; N-phenyl-1-naphthylamine, N-phenyl-2- Naphthylamine, N-
Examples include N-phenylnaphthylamine such as (p-todecylphenyl) -2-naphthylamine; dinaphthylamine such as N-alkyl-phenothiazine; and dithiocarbamate derivative. Generally 0.5 to about 1.5 parts of antioxidant is used.

Generally, about 0.3 parts of antiwear agent and 1 to 2 parts of heavy pressure (EP) agent are used in mist oil. Examples of this type include sulfated fatty acid esters such as sulfated isooctyl tarate;
Sulfated terpenes; Sulfated olefins; Organopolysulfides; Amine phosphates, alkyl acid phosphates, dialkyl phosphates, amine dithiophosphates, trialkyl or triaryl phosphorothionates, trialkyl or trial phosphines, dialkyl phosphines. Feites such as triphenyl phosphate, trinaphthyl phosphate, tricresyl phosphate,
Organophosphorus derivatives including diphenyl cresyl or dicresyl phenyl phosphate, naphthyl diphenyl phosphate, triphenyl phosphorothionate; dithiocarbamates such as antimony dialkyldithiocarbamates; xanthate and the like.

Dibasic acid as a metal deactivator (passivator) and rust corrosion inhibitor,
For example, azelaic acid; propyl gallate; quinoline; quinone and anthraquinone; benzotriazole derivatives such as tolyltriazole; benzoquanamine; aminoindazole; metal alkyl sulfonates such as barium dinonylnaphthalene sulfonate; alkenyl succinic acid or its esters and amides. There are derivatives, etc. Generally 0.02 to 0.2 parts of this type of additive are used.

Small amounts, usually 0.0005 to 0.05 parts of antifoam agents such as silicone oils, acrylates or common products known to suppress foam can also be added. Small amount, usually 0.001 to
It is also convenient to add 0.05 parts of an emulsifying agent. Emulsifying agents used for this purpose include metal alkyl sulfonates, alkylated phenols, alkoxylated alkyl phenols, monohydric alcohols, alkylene glycols and the like.

So-called "multipurpose" commercially available from additive manufacturers
Alternatively, "universal" additives can be utilized and are often convenient. It is commercially available under various trade names such as "Elco 345", "High Tech 323", and "Rubrizol 5034". These additive formulations generally have good oxidative stability,
It imparts antiwear properties and great pressure to the formulated fluid. If the additive formulation is used in low concentrations, however, it may be necessary to add further corrosion inhibitors and antifoams.

The lubricant composition of the present invention is particularly suitable for use in a mist oil system due to its excellent mist characteristics, but it is a helical gear,
It can also be used for general lubrication of unpoided or hypoid gears, spiral bevel gears and pinion gears, and also for tapered bearings.
These can be used in closed and open gear boxes, including transmission cases, torque converters, and also for conventional journal designs. They are also convenient for lubricating chains, pulleys and wire ropes.

The following examples fully illustrate the invention and its various embodiments. All parts and percentages are by weight unless otherwise noted. The molecular weights reported in this specification were measured by gel permeation chromatography using a Water Associates HPLC204 type instrument equipped with a differential refractive index tester (R401 type). The inspection machine was set to a dilution degree of 16. 10 ⁴ , 10 ³ , 500 and 1000 ultra styler gel tubes connected in series and kept at 35 ± 0.1 ° C were used. Tetrahydrofuran was used as the eluting solvent at a flow rate of 1.0 ml / min.
Dissolve the sample in tetrahydrofuran (50mg / ml THF) 50μ
A sample was injected for each measurement. Known molecular weight (240,000
10 to 60 1) 10 polystyrene resin was used as a measurement standard. Mist properties were measured according to the general method ASTM D 3705-78. The oil temperature was maintained at 120 ° F during the test. The air temperature used for the measurements was 150, 175 ° F or 200 ° F.

Example I 63.1 parts of di-2-ethylhexyl dimerate (40 ° C. viscosity
91 centiotoks, viscosity index 155, crystallization point -50 ° F, acid
Value <3, hydroxyl value 2) 27.5 parts of isobutylene polymer
(W7573) and 0.33 parts of isobutylene polymer (w8
9,793) and made a mist lubricant. Mixed 90
℃ and polyisobutylene before mixing with ester
Melted into an inert hydrocarbon. Cool the resulting mixture to approximately 60 ° C.
Commercially available ashless multipurpose gear oil additive (ELCO 345)
Was added with stirring. Mist lubricant (ISO class 460) is next
It had the following characteristics: Viscosity (ASTM D-445) 40 ℃ cst 466 〃 100 ℃ cat 44 Viscosity index (ASTM D-2270) 148 Total acid number (ASTM D-974) (mgKOH / g) 2.5 Specific gravity 60 / 60 ° F (ASTM D-1298) 0.900 flash point, ° F (ASTM D-92) 415 crystallization point, ° F (ASTM D-97) -20 Mist characteristics measured at 175 ° F and 200 ° F as follows
Atsuta:175 ° F 200 ° F Oil production (g / hr) 32.8 39.6 Reclassified oil% 76.9 77.5 Mid-aggregation% 12.1 11.4 Dissipated mist% 11.0 11.1 The results show that the mid-aggregation is minimal and the dissipated mist is very low.
It is clear that the amount of tetrachloride produced is high. Mainly commercial offal oil
A considerable amount of production can be obtained even if a mist lubricant is used.
Long-term operation under the operating conditions necessary to obtain the amount of
Suppresses the flow of mist lubricant and, in some cases, completes the reclassification machine head.
Significant wax precipitation occurs which causes total occlusion. the above
Wax formation can be achieved by using a synthetic synthetic ester mist lubricant.
Operation conditions without occurrence or change of mist distribution
It is possible to continuously operate this system without adjusting the
It was

Mist oil was used to lubricate the bearings on the rolls of a rotating forge (19 inch inner diameter double roller type) in a high temperature hot mill. Mist was made using a commercial mist generator with 2-3 gallons of thumb. Sam oil was heated to about 100 ° F. Mist It was pulled out of the generator by an inch pipe and sent to the reclassifier through the manifold. A conventional reclassifier head with 0.067 holes 9 or 15 was used. The synthetic ester lubricant showed good misting characteristics, and no restraint or blockage of the reclassifier head was observed. Further excellent lubrication was obtained.

In tests involving bearings 30, a 15 to 20% tonnage increase per bearing was obtained compared to the commercial oil-based mist lubricants conventionally used in mills with the synthetic ester lubricants formulated above. Moreover, during routine maintenance (which was done after 150,000 tons of normal operation), the "dry neck" or under-lubricated area was virtually absent for roll necks lubricated with the mist oil composition of the present invention. "Dry nets" were almost always found outside the roll necks where the bearings were seated by the petroleum-based mist lubricant.

In another test over 10 weeks of equipment operation, a number of bearings were lubricated with the above prepared synthetic ester ISO 460 mist lubricant and the same number of bearings were lubricated with a commercial ISO 460 petroleum based mist lubricant. Both bearing groups were examined under comparable operating conditions. During the test period, ester-based mist oil lubricant was used 1
Only the bearing burned, i.e. the bearing burned onto the roll neck.
On the contrary, 12 of the bearings lubricated with oil-based mist oil burned.
In the regular maintenance inspection at regular intervals, an additional 8 bearings in the latter group were judged to be damaged and were discarded. No bearings using synthetic ester lubricant were found to be damaged in this normal maintenance inspection.

Example II For comparison purposes and to demonstrate the need to use a mixture of low and high molecular weight isobutylene polymers, three ISO 460 grade mist oil compositions were prepared by the method of Example I. The composition was as follows: II A II B II C Di-2-ethylhexyl dimethyl 63.1 62.5 63.1 Polyisobutylene (w7573) 27.5-28.4 Polyisobutylene (w89,793) 0.33 11.2-Additive 3.5 3.5 3.5 Mist properties of each of the above ISO 460 formulations were examined at 150 ° C as follows: II A II B II C Oil production (g / hr) 31.8 4.8 38.7 Reclassified oil% 74.4 68.3 71.4 Mid-aggregation% 10.8 6.3 6.3 Loss % Mist 14.8 25.3 22.3 It is clear from the above results that the dissipated mist of Formulations IIB and IIC is unacceptably high. Dissipated mist is generally acceptable at 15% or less. 20% or more of the lost mist is unacceptable at all. In addition, the amount of product IIB produced was uncertain. Only product IIA, which was a mixture of ester with high and low molecular weight polyisobutylene, provided adequate yield and suitable mist properties that could be used for roll bearing lubrication.

Example III The following comparative experiment was conducted to demonstrate the importance of polyisobutylene molecular weight. In this example, a mist oil formulation consisting of di-2-ethylhexyl dimerate and an isobutylene polymer within the above molecular weight range was made and compared to a formulation made using polyisobutylene outside the specified molecular weight. The average molecular weight of the mixed polyisobutylene, that is, the polymer mixture was the same (w8550) in each formulation. Each oil was also blended to the same viscosity, ISO grade 460. The mist oil formulation is as follows: III A III B I
II C di-2-ethylhexyl dimethyl 63.1 60.0 3
4.5 Polyisobutylene (w7573) 27.5 −
− 〃 (w89,793) 0.33 −
4.08〃 (w77,284) − 2.35
− 〃 (w3199) − 30.2
− 〃 (w1874) − −
9.64 Additive 3.5 3.5
3.5 Results of mist characteristics of each formulation measured at 175 ° F as follows: III A III B III C Oil production (g / hr) 32.8 20.8 15.9 Reclassified oil% 76.9 66.2 66.8 Mid-aggregation% 12.1 20.2 16.0 Loss Mist% 11.0 13.6 17.3 From the above results, it is clear that the amounts of III B and III C prepared by using an isobutylene polymer having a molecular weight other than the specified molecular weight are significantly lower than those of the product III A. Products III B and III C are generally unsuitable as mist oils due to their low yield and lack of use in lubricants, i.e. the large amount of oil that agglomerates in the middle or is lost as dissipated mist. Only the product III A formulated according to the invention gives satisfactory production and balanced properties.

Example IV To demonstrate the versatility and low viscosity synthetic mist oil production capacity of the present invention, a lubricant composition was formulated according to the following formulation: di-2-ethylhexyl dimellate 77.5 parts polyisobutylene (w7573) 14.5 parts polyisobutylene. (W89,739) 0.66 parts Elco 345 Multipurpose additive 3.5 parts Properties of this mist oil composition as follows: Viscosity (ASTM D-445) 40 ° C cst 219 〃 100 ° C cst 26 Viscosity index (ASTM D-2270) 149 Total acid number (ASTM D-974) (mgKOH / g) 2.1 Specific gravity 60/60 ° F (ASTM D-1298) 0.902 Flash point, ° F (ASTM D-92) 430 Crystallization point, ° F (ASTM D- 97) -40 Mist characteristics (at 175 ° F) Oil production (g / hr) 52.4 Reclassified oil% 75.7 Mid-aggregation% 13.1 Lost mist% 11.4 Mist characteristics (at 200 ° F) Oil production (g / hr) 63.6 Reclassified oil% 74.4 Mid-aggregation% 11.4 Lost mist% 14.2 This lubricant was an effective mist oil suitable for bearing lubrication.

Sulfated isooctyl tareate 2 instead of commercial additive
Part, phenyl α-naphthylamine 1 part, tricresyl phosphate 1 part, benzotriazole 0.05 part, ethylene glycol dodecenyl succinate half ester 0.
An effective mist oil with comparable properties is obtained when a formulation is prepared with 05 parts, 0.005 parts Dow DC-200 polydimethyl-siloxane and 0.1 parts propylene glycol.

Example V An ISO 320 mist oil composition was prepared by mixing the following ingredients: di-2-ethylhexyl dimerate 70.7 parts polyisobutylene (w7573) 20.7 parts polyisobutylene (w89,793) 0.50 parts commercial universal additive (S20 .5%; P1%) 3.5 parts The physical properties and mist characteristics of the obtained mist oil composition are as follows: Viscosity (ASTM D-445) 40 ° C cst 316 〃 100 ° Cst 33 Viscosity index (ASTM D- 2270) 147 Total acid number (ASTM D-974) (mgKOH / g) 1.9 Specific gravity, 60/60 ° F (ASTM D-1298) 0.904 Flash point, ° F (ASTM D-92) 420 Crystallization point, ° F (ASTM D-97) -25 Mist characteristics (at 175 ° F) Oil production rate (g / hour) 41.7 Reclassified oil% 75.5 Mid-flocculation% 13.9 Loss mist% 10.5 Mist characteristics (at 200 ° F) Oil production rate (at 200 ° F) g / h) 55.0 Reclassified oil% 74.5 Mid-flocculation% 11.8 Dissipated mist% 13.8 Example VI Other synthetic esters to demonstrate the ability to use isotridecyl and Using a mixture of source decyl trimethylolpropane Tate ISO4
I made 60 mist lubricant. The usual way (40
A mist oil composition was prepared with a viscosity of 250 centistokes; acid value of 0.02; hydroxyl value of 1.8; crystallization point of -20 ° F).

Isotridecyl trimellitate 79.5 parts Polyisobutylene (w7573) 14.0 parts Polyisobutylene (w89,793) 0.17 parts Additives 3.5 parts Mist characteristics (175 ° F) were as follows: Oil production (g / hr) ) 34.9 Reclassified oil% 74.5 Mid-way coagulation% 14.5 Dissipated mist% 11.0 The product shows good lubricity and is an effective lubricant for bearings.

Example VII Trimethylolpropane triisostearate (40 ° C. viscosity 90 centistokes; acid value 5; hydroxyl value 10; crystallization point -15)
° F) based mist oil composition was prepared as follows: trimethylol chloropropane triisostearate 68.5 parts polyisobutylene (w7573) 23.1 parts polyisobutylene (w89,793) 0.28 parts erco 345 3.5 parts scratched The lubricant composition had a viscosity of 459 centistokes at 40 ° C. and a 175 ° mist characteristic of oil production (g / hour) 31.7 reclassified oil% 73.9 mid-aggregation% 15.5 dissipated mist% 10.6. Comparable mist properties and lubricity were obtained when the commercial additive was replaced with 4 parts antimony dialkyldithiocarbamate, 1 part tricresyl phosphate and 1 part barium dinonyl naphthalene sulfonate.

Example VIII Trimethylolpropane trioleate (40 ° C. viscosity 228
Centistokes; acid value 4; hydroxyl value 4; crystallization point -50 ° F) 5
6.5 parts were mixed with 33.0 parts polyisobutylene (w7573) and 0.40 parts polyisobutylene (w89,793) to make ISO 460 mist oil. To this formulation was also added 3.5 parts of a commercially available universal additive. The resulting mixture had a viscosity of 454 centistokes at 40 ° C and showed good lubricity and mist characteristics. Mist characteristics (175 ° F) were as follows: Oil production (g / hr) 29.2 Reclassified oil% 71.8 Mid-aggregation% 16.4 Dissipated mist% 11.8 The product was effective for high temperature strip mill roll bearing lubrication . After long-term operation, there was no evidence of wax formation, and the roll neck and bearing surface were visually inspected to show good spreadability of the lubricant.

Example IX A series of ISO 460 mist oil compositions were made using various amounts of high and low molecular weight polyisobutylene. The composition was as follows: IX A IX B I
XC di-2-ethylhexyl dimethyl 63.1 63.1 63.
1 Polyisobutylene (w7573) 25.8 27.1 2
8.0 Polyisobutylene (w89,793) 0.99 0.50
0.17 Additive 3.5 3.5
3.5 Results of mist characteristics measured at 175 ° F (excluding IX A) and 200 ° F are as follows: IX A IX B IX C oil production (g / hr) at 175 ° F Trial 33.1 39.9 Reclassified oil% Test 77.9 76.7 Mid-aggregation% No 12.4 9.8 Lost mist% No 9.7 13.5 Oil production at 200 ° F (g / hr) 35.9 44.5 39.6 Reclassification% 76.0 77.1 74.5 Mid-aggregation% 14.1 10.6 11.6 Lost mist% 9.9 12.3 13.9 Example X The average molecular weight of the high molecular weight polyisobutylene used is 77,2
A mist lubricant was prepared by the general method of Example I except 84. To prepare the composition, 63.1 parts of di-2-ethylhexyl dimerate was added to polyisobutylene (w7573) 27.5
Parts and 0.39 parts of high molecular weight isobutylene polymer. 3.5 parts of a commercially available universal additive was also added to the mixture. The viscosity (40 ° C) of the obtained mist lubricant was 464 centistokes, and the mist characteristics (175 ° F) were as follows: Oil production (g / hr) 32.0 Reclassified oil% 72.7 Mid-way aggregation % 14.8 Dissipated Mist% 12.4 The product has lubricity comparable to that of Example I and is effective for mist lubrication of high temperature roll mills and other bearings.

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Claims (9)

[Claims] (1) (a) A polyol ester obtained from an aliphatic polyol having 2 to 8 hydroxyl groups and 3 to 12 carbon atoms and an aliphatic monocarboxylic acid having 5 to 20 carbon atoms; (B) trimellitate or its anhydride and a trimellitate ester obtained from an aliphatic alcohol having 5 to 16 carbon atoms; and (c) a polymerized fatty acid and C containing 75% or more of C ₃₆ dimer acid.
_2-13 Polymerized fatty acid ester obtained from monofunctional alcohol; Viscosity at 40 ° C selected from the group consisting of 15 to 300
45 to 95 parts by weight of synthetic ester having centistokes; (2) 100% polymer standard, average molecular weight 4,000 to 10,0
8 to 40 parts by weight of polyisobutylene having 00; and (3) average molecular weight of 25,000 to 30 based on 100% polymer.
An improved lubricant composition suitable for mist lubrication, characterized in that the composition comprises 0.1 to 1 part by weight of polyisobutylene having 000; and the viscosity of the composition at 40 ° C. is 125 to 750 centistokes. 2. The polyol ester (a) has an acid value of 15 or less having 5 to 8 carbon atoms and 2 to 4 hydroxyl groups.
It is obtained from an aliphatic polyol having a hydroxyl value of 100 or less, the trimellitate ester (b) has an acid value of 15 or less and a hydroxyl value of 10 or less, and the polymerized fatty acid ester (c) is 100 or less. The lubricant composition according to claim 1, which has an acid value of 10 and a hydroxyl value of 10 or less. 3. The polyisobutylene (2) is 4,500 to 8,500.
Polyisobutylene (3) with an average molecular weight of 50,0
Claim 1 having an average molecular weight of 00 to 200,000.
Item 3. The lubricant composition according to item 2 or item 3. 4. A method according to claim 1, which has a viscosity of 175 to 550 centistokes and contains (1) 55 to 85 parts, (2) 12 to 30 parts and (3) 0.25 to 0.85 parts. Two
Item 4. The lubricant composition according to Item 3. 5. (a) is neopentyl glycol, 2,2-
Dimethyl-3-hydroxypropyl-2,2-dimethyl-
3-hydroxypropionate, 2,2,4-trimethyl-
A polyol and CP selected from the group consisting of 1,5-pentanediol, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, dipentaerythritol, tripentaerythritol.
_12-18 derived from an aliphatic monocarboxylic acid;
(B) is obtained from trimellitic acid or its anhydride and a C _10-13 aliphatic alcohol; and (c) is
The lubricant composition according to any one of claims 1 to 4, which is composed of a polymerized fatty acid containing 85% or more of C ₃₆ dimer acid and a C _8-10 aliphatic monoalcohol. 6. (a) is trimethylolpropane trioleate or trimethylolpropane triisostearate; (b) is isodecyl trimellitate, isotridecyl trimellitate or isodecyl isotridecyl mixed trimellitate. The lubricant composition according to any one of claims 1 to 4, wherein (c) is diisodecyl dimellate or di-2-ethylhexyl dimellate. 7. A lubricant composition according to claim 1, further comprising up to 8% by weight of additives. 8. (1) (a) A polyol ester obtained from an aliphatic polyol having 2 to 8 hydroxyl groups and 3 to 12 carbon atoms and an aliphatic monocarboxylic acid having 5 to 20 carbon atoms; (B) trimellitate or its anhydride and a trimellitate ester obtained from an aliphatic alcohol having 5 to 16 carbon atoms; and (c) a polymerized fatty acid and C containing 75% or more of C ₃₆ dimer acid.
_2-13 Polymerized fatty acid ester obtained from monofunctional alcohol; Viscosity at 40 ° C selected from the group consisting of 15 to 300
45 to 95 parts by weight of synthetic ester having centistokes; (2) 100% polymer standard, average molecular weight 4,000 to 10,0
8 to 40 parts by weight of polyisobutylene having 00; and (3) average molecular weight of 25,000 to 30 based on 100% polymer.
0.1 to 1 part by weight of polyisobutylene having 000; and a mist of the composition characterized in that the viscosity of the composition at 40 ° C. is 125 to 750 centistokes at a pressure of about 10 to 100 psig. A method of lubrication in which air is generated in the air to be squeezed and transported to a metal surface to be lubricated, aggregated into large droplets and deposited on the metal surface to form a lubricious film thereon. 9. A method according to claim 8 wherein the air temperature is 125 to 200 ° F. and the air pressure is 20 to 80 psig.