US2043923A - Lubricant composition - Google Patents

Description

. June 9, 1936.

A. w. BURWELL LUBRICANT COMPOSITION Filed Jan. l5, 1934 5 Sheets-Sheet l I/mcompounakd railway m'r oz'b,

Bear/hg @gis/1re. /s. per s@ June 9, 1936.

A. w BURWELL.

LUBRICANT COMPOSITION Filed J'ap. '15, 1934 3 Sheets-Sheet 2 Standard ergga'ne pa'l F gf -rzzzrcrzealY abr/cantal n l 5 700 800 @per J9@ 01,6017/ g und 30a 40o 5w 5m Laad.

,Fd/wax.

Filed Jan. 15, 1934 3 Sheets-Sheet 5 per sqm 31a/UWM:

Ml/W36- Patented June 9, l1936 LUBBICANT COMPOSITION Arthur W. Bnrwell, Niagara Falls, N. Y., assignor to Alox Corporation, New York, N. Y., a corporation of New York Application January 15, 1934, semi Nar-106,140

2 Claims.

The present invention relates to the production of improved lubricant compositions comprising lubricating oils of mineral origin as their bases, and is concerned more particularly with a composition produced by admixing with a lubricating oil a plurality of diierent substances each having the function of enhancing the lubricity of the oil.

In U. S., PatentV No. 1,863,004 to Arthur W. Burwell it was disclosed that the lubricity of'a lubricating oil of mineral origin may be improved by the addition thereto of a relatively very small but effective amount of an oil'soluble addition material of mineral origin, which material was substantially free of hydrocarbons and consisted essentially of high-molecular-weight aliphatic oxygen-containing compounds including a substantial proportion of free saturated aliphaticl carboxylic acids. It was there disclosed that Vsuoli addition material is obtainable by the controlled, liquid-phase oxidation of scale wax, Sharples wax (i. e., the sticky, amorphous, translucent, solid obtained by diluting crude petroleum with light petroleum distillate, chilling the mixture to about minus 17 F., and centrifugally separating precipitated solids from the chilled mixture), a petroleum distillate, or the like, at a temperature of from about to about C. and at a superatmospheric pressure not greater than about 320 pounds perl square inch, in the presence of an exciter of oxidatum, unta the point of incipient formation of compounds which are insoluble in petroleum and in the reaction mixture, such mixture comprising saponiable and unsaponiiable components, separating the saponifiable components from at least the major portion of the unsaponiable components, removing the more readily volatile ingredients of the separated saponifiables portion and drying the resulting residue. Likewise, in application Serial No. 700,018, filed November 27, 1933, in the names of Arthur W. Burwell and Adolf Kempe, it has been disclosed that wholly neutral mixtures of such oxygen compounds of relatively high-molecular-weight hydrocarbons of mineral origin-specifically, neutral esters prepared from the acids disclosed in said Burwell Patent No. 1,863,004-have the property of enhancing the lubricity of a lubricating oil of mineral origin. Whether in the esterized form or in the free form, these originally acidic mixtures of oxidized hydrocarbons are lubricant aids or lubricity-enhancing materials, and are so denominated herein.

It has now been found that mixtures of such lubricant aids prepared from a plurality of different starting materials have materially greater eilect in lubricant compositions comprising lubricating oil than have the lubricant aids prepared from a single starting material, and it is the essence of the present invention to provide improved lubricant aids by combining or blending lubricant aids derived from at least two dissimilar (or at least different) starting materials of lubricant aid derived from crude scale wax produces a lubricant which has a materially lower internal resistance and is capable of withstanding materially higher pressures than is the case with the oil per se; that the substitution of a like amount of a similarly prepared lubricant aid derived from amorphous, or Sharples, wax for the lubricant aid derived from scale wax in the above lubricant composition shows very nearly 'equivalent improvements in the aforesaid prop erties; While the substitution of a like amount of a mixture of similarly prepared lubricant aids derived from crude scale wax and from amorphous wax produces a composition having a materially reduced internal friction as compared either with the scale wax aid composition or with the amorphous wax aid composition alone, which composition far exceeds the pressure-sustaining properties of the other two compositions. Typical of the data supporting the above statements are the following data collected relative to (a) the internal friction and (b) pressure-resisting properties of a motor lubricating oil and of compositions prepared from that oil, it being noted that these tests were made using a Lubarometer testing machine of 1000 pounds per square inch pressure capacity:

free acids; (2) those acids in completely neutral esteriz'ed form; (3) unsaponiiiable oxidation produets such (as was mentioned hereinbefore) as the naturally completely neutral and unsaponiiiable mixtures of alcohols, alcohol-ketones and ketones derived by removing all saponiable material from an oxidation reaction mixture; or (4) mixtures of the above agents. l

'Ihe following specific examples, taken in connection with the accompanying drawings, in which Figs. 1, 2 and 3 are graphs showing relationships between bearing pressures and (a) tangent friction drags and (b) coemcients of friction of the lubricant compositions described in the correspondingly numbered examples, will serve to illustrate and further describe the invention:

Example 1 The oil used as the basis of test in this example was a railway car oil having of itself Va very high resistance to shock and to film rupture. It had been prepared from a -20 F. cold-test pressed oil (from wax distillate) which had been reduced. for flash and fire test, in a still using much bottom steam to prevent cracking of the oil hydrocarbons, and thereafter had been subjected to vigorous aeration in the presence of free steam, at at- (c) 36-40 distillate (i. e., fuel oil o r light ends of pressed oil taken oi upon second distillation). These three so-called ketonic lubricant aids in each case consisted essentially of acid-free unsaponiable and completely neutral oxidation products of the hydrocarbons of the named starting material.

The oil was tested alone: thereafter to another portion of the same oil 1% by weight of the above mixture was added and the resulting composition was similarly tested; and finally a composition consisting of 98% by weight of the oil and 2% of the above mixture was tested in the same manner. In this test the bearing metals lubricated were steel and bronze; the bearing speed was 500 feet per minute; the bearing temperature was maintained constant at 140 C.; and the increase in tangent friction drag with increasing bearing pressure was measured in pounds per square inch.

The influences of the mixed lubricant oil in lowering the tangent friction drag, and the coeiiicient of friction, respectively, of the railway car oil, whenI added thereto in relatively very small amounts, are shown in Fig. 1, in which the solid lines marked #1 represent the uncompounded oil, the dot-and-dash lines marked #2 represent the oil composition containing but 1% of the aforesaid mixed lubricant aid, and the broken lines marked #3 represent the oil composition containing 2% of the said mixed lubricant aid. Relative to the coeflicient of friction curves, it will be noted; that the 1% composition (line #2), within the range of from 200 to 650 pounds perl denced no suggestion of imminent film rupture on the part of the 2% composition even at the maxl- In this case the following compositions were compared:

Composition C=99.5% of a standard engine oil known as Renown Engine, into which'there was blended 0.5% of a mixed lubricant oil produced by mixing equal parts by weight of the lubricant aids produced, in accordance with the process described and claimed in Burwell Patent No. 1,863,004, from (1) parafllne wax and (2) amorphous or Sharples wax.

Composition D=99.5% of 28 paramne oil, having a viscosity of 100 Saybolt `at 100 F., and 0.5% of the mixture of lubricant aids referred to under C" above. Y

Composition E=99.0% of the 28 parafline Oil of composition "D above, plus 1.0% of the mixture of lubricant aids referred to under C above.

These three compositions were tested for coefficient of friction and tangent friction drag, using a bronze bearing and a steel shaft with peripheral speed maintained at 500 feet per minute.

Fig. 2 shows the plotted results of the test, in which the bearing loads were progressively increased, by 100 pound increments, from 100 pounds to 1,000 pounds.

The following data. is supplementary to that shown in Fig. 2:

l E-126 F. Each composition was tested for 30 minutes at the maximum load of 1,000 pounds,-

and showed less than 5 increase in temperature above the average of the tests.

All three compositions showed very similar characteristics: they had very low values of friction coeilicient and of drag, and at maximum pressure capacity of the testing machine gave no indication of approaching-film rupture.

Composition E showed properties in all respects as good as those of castor oil, with a considerably lower coeflicient of friction (at all points) than that of castor oil.

Illustrating the effect of a mixed lubricant ald when blended in very small amount with a lubricating oil of Coastal type, 0.3% by weight of the mixed lubricant aid referred to in C of Example 2 above was admixed with 99.7% of "200.

Pale Coastal Oil, and this composition, denominated Oil A compounded, was compared as to tangent friction drag and to coefficient of friction with said oil unblended, denominated Oil A. The data of this comparative test are shown in Fig. 3.

It is to be noted that the,uncompounded oil showed .a markedly higher coeficient of friction, at all points, than did the composition, and that the uncoznpounded oil failed at 900 pounds pressure while the composition still was capable of sustaining further increments of pressure without iilm rupture. ture rose to 142 F. in the case of Oil A whereas maximum bearing temperature in the case of Oil A compounded was 137 F.

. Mixed lubricant aids other than those specically illustrated above may be employed. Thus, for instance, there may be used mixtures of deacidif-led oxidized products from a plurality of different sources, such as may be produced by removing free acids from the-oxidation reaction Maximum bearing tempera- 4mixtures from two or more diierent sources, by

oxidation, separation and treatment of 4each of a l plurality of different starting materials is not necessary for the provision of the mixed lubri cant aids of the present invention, since the latter may be prepared from oxidation reaction mixtures derived from a mixture of two or more different starting materials. For example, Sharples wax may be mixed with afnormally liquid fraction of petroleum and the resulting mixture oxidized, and subsequently processed in. the manner hereinbefore described with respect to single starting materials. I claim:

1. A lubricating oil composition comprising a major proportion of a lubricating oil and a minor proportion of a lubricity-increasing agent soluble in said oil, said agent consisting o! a; mixture of lubrlcity-increasing oxidation products derived l0 from at least two diierent petroleum hydrocarbon materials of the group consisting of scale wax, amorphous wax and normally liquid petroleum hydrocarbons.

claim 1, characterized in that the said oxidation products are neutral.

anion w. Buavvrm..

2. The iubrioating on oomposition defined in 1s

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