US2122940A

US2122940A - Lubricant

Info

Publication number: US2122940A
Application number: US757969A
Authority: US
Inventors: Walter D Hodson
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-12-17
Filing date: 1934-12-17
Publication date: 1938-07-05
Anticipated expiration: 1955-07-05

Description

Patented July 5, 1938 V UNITED: STATES PATENT OFF-ICE 1 No Drawing.

16 Claims.

The present invention relates to improvements in greases, and will be fully understood from the following description thereof.

This application is a continuation-in-part of 5 my copending application Serial Number 412,929. The present invention relates to greases of an unotuous character consisting principally of a lubricant oil and a gelling metallic soap, such-- greases having a great adherence to the parts to be lubricated and a strong resistance to being squeezed out under load. Ordinarily lead soaps are employed in such greases, such as the lead soaps of oleic acid, fish oils, stearic acid, castor oil, linseed oil, degras, resin, or naphthenic acids. 5 Other gelling metallic soaps which may be employed are the similar soaps of aluminum, calcium, zinc, copper, manganese, magnesium and the like. In general, the use of the lead soaps, for example, the naphthenate, oleate or fish oil soaps, is preferred. However, soaps of other metals or mixtures of soaps of difierent metals or other gelling or body-imparting materials capable of imparting to the oil the desired characteristics may be employed. Water-soluble soaps such as sodium soaps may be used, but

with such soaps, particular care must be used to prevent theformation of soluble oils suchas cutting oil. A

In the manufacture of such greases, wherein adhesion and resistance to squeezing out under load are desired, it is necessary to incorporate into the mineral lubricant oil employed substantial quantities of the non-setting, gelling soap. For example, the proportions desired may be as high as from 20% to 60% of the soap, but such proportions of the soap result in an extremely heavy, viscous material which does notreadily flow and the use of which may be entirely impractical in bearings with small clearance or gpwhen there is occasional or continuous exposure to a low temperature. The low fluidity of suchgreases has rendered necessary the use of relatively small proportions oi, the soap, or has prevented entirely the use of such compounds.

I have found that a fluidity of s'uchcompounds may be modified by incorporating therein a small proportion, rangingordina'rily from to 10%, 01' organic oil-miscible solvents having a boiling point of 80C. or' higher, and preferably of from 150 to 250 C. These organic'solven'ts, which are completely miscible with the oil-soap compound, are of the type now generallydesignated as lacquer solvents. For example, I have successfully employed such oil-miscible solvents as ethylene dichloride, dichlorethylether, diethyleneglycol, the monoallwlethers oi. ethyleneglycol and di-. ethyleneglycol and their esters, such as ethylenelycol, monoethylether, ethyleneglycol, monoethylether acetate, ethyleneglycol monobutylether, diethyleneglyool monoethvlether, diethyl- Application December 11, 1934, Serial No. 757369 ene glycol monobutyiether,triethanolamine, and the like. Equivalent solventssuch as phenyl chlorides, including monochlor benzene, orthodichlor benzene, and trichlor benzene may'likewise be used. The phenyl chlorides, and particularly monochlor benzene are preferred for calcium basegreases. For, example, I have found 5 ethyleneglycol monoethylether, dichlorethylether, and ethylene dichloride to be particularly desirable in increasing the fluidity of such compounds. The proportion of such solvents which may be employed varies, depending upon the characteristics of the compound in which it is incorporated and the characteristics desired in the final product. Thus, from to 1% of the solvent has an appreciable effect in reducing the viscosity and increasing the fluidity of the compound. Ordinarily, for example, with a content of lead fish oil soap, say of 5 to 30%, from 3 to 5% of such a solvent, for example, dichlorethylether or ethylenedichloride may be employed. With the com pounds containing higher proportions of the soap, say 30 to up to.10% or even more of the solvent may be 'incorporated- The solvent may be selected and the proportions thereof adjusted in accordance with the desired use. For example, in bearings with, smaller clearances, more solvent may be employedto secure a greater fluidity, and a more volatile solvent may be employed to permit its rapid evaporation.

Occasionally, the compounds containing the solvent may show some settling on long standing, as in compounds containing a small amount of the soap'in a low-viscosity oil and I have found that this may be prevented by incorporating into the composition a small proportion of a high boiling organic ester, having preferably a boiling point of from 250 to 450 C. or higher. For example, I have employed 'for thispurpose such esters as trlcresyl phosphate, butyl phthalate, amyl phthalate, dibutyl phthalate,butyl stearate, ethyl acetate, or the like. Dibutyl phthalate' I have found to be particularly effective. From to 2 or -5% of such high boiling esters, while miscible with the oil and the oil solvent employed, are ordinarily suiiicient.

As will be readily understood, the lubricant oil employed and the specific metallic soap will be selected in accordancewith the practice of the art to secure the desired type of lubrication. Thus, for small high speed units, the gears and bearings require a relatively'low viscosity mineral oil, say 75. to 150 sec. Saybolt at F., while for-heavier duty gears and bearings, higher viscosity oilsmay be employed and larger proportions of the soap may be present. The pres V ence of the solvent and thestabilizing material in accordance with the present invention does not materially alter the lubricating characteristics of the compound apart from markedly in- 6 creasing its fluidity and extending its ada bility in use. The compound retains its desirable qualities of adherence to metal and resistance to squeezing out under load. The solvent may be in part dissipated in use, but since such loss occurs-after application of the lubricatingcompound, andqafter its penetration into the working parts of the bearing or gearing, it does 'not adversely affect the value of the compound,

but is, in fact, frequently desirable.

- A sodium soap grease may be prepared containing 10-50% of a sodium soap such as oleate, stearate or the like (preferably tallow fat acids) and the balance mineral oil of the desired viscosity. A typical grease will contain 30% sodium soap and 70%, of a heavy steam-refined cylinder stock mineral oil, for example, having a viscosity of 200 Saybolt at 210 F. Such a grease will be extremely hard, and particularly suitable for use in lubricating roll neck bearings. With the par ticular sodium soap described 2%% of butyl Carbitolis preferred as a solvent.

and desire to secure by and a non-setting, gelling soap, said compound including a minor proportion of an aliphatic oil-miscible grease-compatible organic solvent whereby the-fluidity thereof is increased, and a stabilizing organic ester, selected from a group consisting of tricresyl phosphate, butyl phthalate,

amyl phthalate, dibutyl phthalate, butyl stearate, and ethyl acetate.

2. An adherent, fluid, lubricating compound composed'principally of a viscous mineral oil and a non-setting, gelling soap, said compound including a minor proportion of an aliphatic oil-miscible grease-compatible organic solvent,

whereby the fluidity thereof is increased, and a stabilizing organic ester having a boiling point between 250 and 450 C., selected from a group comprising tricresyl phosphate, butyl phthalate,

amyl phthalate, dibutyl phthalate, butyl stearate,

and ethyl acetate.

3. An adherennlubricating compound composed principally of a viscous mineral oil and a non-setting, geliing' soap, said compound in-- cluding a'minor proportion of an oil-miscible grease-compatible'organic solvent containing a monoalkyl-glycolether group, whereby the fluidity thereof isincreased, and a high boiling organic ester selected from a group consisting of tricresyl phosphate, butyl phthalate, amyl phthalate, dibutyl phthalate, butyl stearate and ethyl acetate.

4.'An adherent, fluid lubricating compound composed principally of a visco s mineral oil and a non-setting'gellingsoap, said compound including dichlorethylether in quantity suflicient to increase the fluidity thereof.

5. An adherent, fluid lubricating compound composed principally of a viscous mineral oil and'a non-setting, gelling soap, said compound including diethylene'glycol monobutyl ether in quantity sufficient to increase the fluidity thereof.

6. An adherent, fluid lubricating compound composed principally of a viscous mineral oil and a non-setting, gelling soap. said compound including ethylene dichloride'in quantity sumcient to increase the fluidity thereof.

7. An adherent, fluid lubricating compound composed principally of viscous mineral oil and -a non-setting, gelling soap, said compound including a minor proportion of ethylene dichloride and a small proportion of dibutyl phthalate. 8. An adherent, lubricating compound containing a mineral oil, from. 10 to 30% of a lead soap, and from 3 to 5% of an oil-miscible grease compatible hydrocarbon derivative solvent capable of increasing the'fluidity thereof without materially affecting the lubricating properties of the lubricating compound.

9. An adherent, lubricating compound composed of a viscous mineral oil and from to 30% of a lead soap, said compound including from 3 to.5% of an aliphatic oil-miscible greasecompatible organic solvent and from A to 3% of a high boiling point ester, selected from a group consisting. of tricresyl phosphate, butyl phthalate, amyl phthalate, dibutyl phthalate, butyl stearate and ethyl acetate.

, 10. A method of modifying the fluidity of greases composed principally of viscous mineral oil and a metallic soap, said soap being present in an amount suflicient to produce a grease structure of the character produced in a lead soap by the presence of approximately 5-30% of the lead soap, which consists in adding an oil-miscible solvent of the class consisting of ethylenedichloride,

dichlorethylether, diethyleneglycol, the monoalkyl ethers of the ethyleneglycoland diethyleneglycol and their esters and phenyl chlorides.

I 11. An adherent fluid grease composed principally of a viscous mineral oil and a metallic soap, thesoap being present in an amount sufllcient to produce a solid grease structure, and said conpoundincluding a minor proportion of an oilmiscible organic solvent of the class consisting of ethylenedichloride, dichlorethylether, diethyleneglycol, the monoalkyl ethers of ethyleneglycol and diethyleneglycol and their esters, and phenyl chlorides, whereby the grease is rendered fluid without material impairment of its grease characteristics.

12. An adherent fluid grease composed principally of a viscous-mineral oil and a gellingmetallie soap, the soap being present in that amount suflicient normally to produce a grease solid at normal temperatures and said grease compound including a small proportion of a liquid oil-miscible, grease-compatible, hydrocarbon derivative organic solvent, whereby the'ffluidity thereof is markedly modified without materially affecting the lubricating faculties of the grease compound.

13. A grease as set forth in claim 12, in which the organic solvent has va boiling, point from 80 C. to 250 C.

14. A compound as set forth in claim 12, in which the organic solvent is present in an amount from A to 10% of the grease.

' 15. A compound as set forth in claim 12, in which the solvent contains a monoelkylglycolether group.

16- A compound-as set forth in claim 12, in

which the organic solvent is diethyleneglycolmv