US2922762A - Twister ring lubricant - Google Patents

Description

United States Patent TWISTER RING LUBRICANT Arnold J. Morway, Clark, N.J., assignor to Esso Research and Engineering Company, a corporation of Delaware N0 Drawing. Application February 13, 1956 Serial No. 564,860

11 Claims. (Cl. 252-35) 'This invention relates to new and improved lubricating compositions and to the method of preparing the same. More particularly, the invention relates to a twister ring lubricant prepared by thickening petrolatum to a grease consistency with a mixture of metal salts of low and intermediate molecular weight carboxylic acids.

This application is a continuation-in-part of S.N. 498,- 741, filed April 1, 1955, and now US. Patent 2,863,847, for the same inventor.

Twister ring lubrication is a problem found in the textile manufacturing art where untwisted yarn is twisted and wound at high speeds upon spools for use in weaving looms. In the twisting and winding operation two or more yarns or piles are brought together and twisted into a single strand and then wound on a spool or bobbin, which is mounted on a spindle within a twister frame. The bobbin stands vertically within a circular metal ring called a twister ring mounted on the twister frame. Riding upon the twister ring and traveling freely on its circumference is the traveler, a looped metal member made of steel or bronze. In the process of twisting and winding, two or more yarns or piles pass through the loop of the traveler, are twisted by its rotational movement around the twister ring, and are wound on the bobbin, rotating upon the spindle. The bobbin rotates at speeds in the neighborhood of 7,000 r.p.m. or more, and the traveler moves around the twister ring at speeds almost as great. Though the traveler weighs only a fraction of an ounce, it may develop several pounds of centrifugal force when operated at top speeds.

It has now been found that twister ring lubricants having excellent lubrication characteristics can be prepared by thickening petrolatum to a grease consistency with a mixture of metal salts. The twister ring lubricants prepared in accordance with the invention are particularly characterized by desirable dropping point and consistency properties as well as outstanding extreme pressure and wear resistant properties.

The petrolatum used in the formulation of the greases of the invention may be any of the white, cream, yellow or amber petrolatums having melting points Within the range of about 75 to 135 F. and A.S.T.M. consistencies of from about 160 to 275 mm./10. In the preferred embodiment of the invention, petrolatums having melting points within the range of about 110 to 135 F. and A.S.T.M. consistencies of about 200 to 275 mm./ are used. In general, the finished twister ring lubricants of the invention will contain about 70 to 95 weight percent, preferably about 75 .to 90 weight percent, petrolatum.

The metal salt mixtures contemplated in the invention comprise the metal salts of low molecular weight monocarboxylic acids having from about 1 to 3 carbon atoms per molecule and metal salts of intermediate colecular weight monocarboxylic acids having from about 7 to 10 carbon atoms per molecule. The relative amounts of the low and intermediate molecular weight carboxylic acids employed will be such as to result in Patented Jan. 26, 1960 or anhydrous metal salt mixtures may be employed to thicken the petrolatum, though the former are employed in the preferred embodiment of the invention. In general, the finished twister ring lubricants of the invention will contain about 5 to 30 weight percent, preferably about 10 to 25 weight percent, of the hydrous mixture of metal salts.

The low molecular weight carboxylic acids useful in this invention include saturated and unsaturated, aliphatic monocarboxylic acids having from about 1 to 3 carbon atoms per molecule such as formic, acetic, propionic, acrylic and lactic acids. Acetic acid is especially preferred. Mixed low molecular weight carboxylic acids wherein the acids contain from about 1 to 3 carbon atoms and have an average saponification value of above about 540 may also be employed.

For the purposes of this invention, those aliphatic monocarboxylic acids which contain from about 7 to 10 carbon atoms, preferably about 8 to 9 carbon atoms, per molecule and which are intermediate in chain length and molecular weight when compared to the low molecular weight and high molecular weight carboxylic acids are designated as intermediate molecular weight carboxylic acids. Either saturated or unsaturated intermediate molecular weight carboxylic acids may be utilized, though the saturated fatty acids are-preferred. Straight chain or substantially straight chain acids are also preferred. vThe average saponification of the single or mixed intermediate molecular weight monocarboxylic acids should be about 310 to 440, preferably about 350 to 420. Some of the intermediate molecular weight monocarboxylic acids, within the above prescriptions, are exemplified by:

5-methyl-2-hexanoic Heptanoic (enanthic) Octanoic (caprylic) 2-ethyl hexanoic C oxo acids Nonanoic (pelargonic) Decanoic (capric) C oxo acids Commercial mixtures of these intermediate molecular weight carboxylic acids having an average saponification value of from about 310 to 440 can also be employed.

The oxo acids useful for the purposes of the present invention, e.g. the saturated branched chain C and C oxo acids, can be prepared by means of the well known oxo synthesis. This process involves the oxonation or carbonylation of olefins with carbon monoxide and hydrogen at temperatures of about 300 to 400 F. and pressures of about 2500 to 4000 p.s.i.g. in the presence of a group V'III metal catalyst, preferably cobalt. In US. Patent No. 2,632,021 the oxo process and the nature of the reaction products, e.g. the C oxo products, are disclosed in detail. The preparation of oxo acids from the oxo reaction products is described in US. Patent No. 2,537,577 and US. Patent No. 2,553,364. Neither the preparation of the oxo reaction products nor the preparations of oxo acids therefrom are considered to be directly related to the essence of the present instability at high temperatures and under mechanical stress to the lubricating compositions of the invention even without the use of conventional extreme pressure additivcs and stabilizing agents. Other metals useful for the purposes of this invention include the alkali metals, i.e. sodium, potassium and lithium and the heavy metals of groups LII, IV and VIII of the periodic system. The heavy metals useful for the purposes of this invention include copper, zinc, lead, cobalt, strontium and maguesium.

The metal components of the salts of the low and intermediate molecular weight carboxylic acids may be any one or more of the metals set forth above. In most cases, however, the low and intermediate molecular weight carboxylic acid salts contain the same metal component.

In general, the lubricating compositions of the invention are prepared by heating the desired petrolatum to a temperature just above its melting point, i.e. at a temperature of about 130 to 140 F. The saponifying agent, e.g. lime, is then added to the melted petrolatum and thoroughly dispersed. A blend of the desired low and intermediate molecular weight carboxylic acids is then added to the fluid dispersion with continued stirring and without the application of further external heating. The heat of reaction raises the temperature of the resulting mixture to about 170 to 200 F. The stirring is continued until the temperature has subsided, and the grease mixture is then cooled. The grease may be finished by being subjected to high rates of shear in the order of about 50,000 to 500,000 reciprocal seconds in such milling or homogenizing devices as a Morehouse mill, Charlotte mill, ink mill, Manton-Gaulin homogenizer, etc. Where it is desirable, conventional lubricating grease additives may be added to the grease prior to homogenization. These conventional additives are employed in amounts of about 0.01 to by weight and include such additives as oxidation inhibitors, corrosion and rust inhibitors, metal deactivators and the like.

As noted above, the cold sett method of manufacture is preferred. This method of employing relatively low temperatures results in the formation of hydrous mixtures of the metal salts of low and intermediate molecular weight monocarboxylic acids and avoids the possibility of effecting changes in the color of the petrolatum due to heating at elevated temperatures. If desired, however, excellent twister ring lubricants may also be prepared by dehydrating the compositions at temperatures above about 210 F. for a period of time sufficient to remove the water which may be present in the mixture. The amount of water present in the hydrous mixtures of metal salts can vary widely. In general, however, the amount of water present will be about 0.5 to 15.0 wt. percent, preferably about 1 to 5 wt. percent, based on the total weight of the hydrous mixture of metal salts.

The hydrous mixture of metal salts may also be prepared by separately preforming at least a portion of the low molecular Weight carboxylic acid salt and/or the intermediate molecular weight carboxylic acid salt. This method is especially useful when difierent metals are employed as bases for the salt constituents. Preformed metal salts can replace about 30 to 80% of the free acids and stoichiometrically equivalent amounts of the bases.

The invention Will be more fully understood by reference to the following specific examples illustrating various modifications of the invention.

EXAMPLE I Four petrolatum based compositions thickened with hydrous mixtures of the metal salts of acetic acid and commercial caprylic acid having the formulations and properties set forth below in Table I were prepared as follows:

Greases A and B.The petrolatum was charged to a grease kettle equipped with efiicient stirring paddles. The petrolatum was melted by heating it to a temperature of about 120-125 F. The lime was then added and thoroughly dispersed. Without further external heating a blend of the acetic acid and the commercial caprylic acid was added to the melted petrolatum. The heat of reaction raised the temperature to above about 175 F., and stirring was continued until the temperature had subsided. The grease was then cooled and homogenized in a Morehouse mill at about 150,000 reciprocal seconds.

Grease C'.-This grease was prepared similar to greases A and B as described above, except that the petrolatum was not melted and the homogenization step was omitted.

Grease D.This grease was prepared similar to greases A and B.

Table I Compositions F'ormulaton (percent Wt):

Glacial Acetic Acid,

Light Amber Petrolaturn 4 Mol ratio acetic acid to commercial caprylic acid radicals Properties:

Appearance Pentration, 77 F Worked, 60 strokes Dropping Point, F

Shell 4 Ball Wear Test (1,800 r.p.m.,

10 kg. load, 75 0., 1 hr.) Spot diameter, mm

5. 8/1 5.8/1 Smooth, uniform greases below 120 1 Sap. No. 327; molecular weight 172. Drew Wecoline AAC; 2 Melting point F.; A.S.T.M. consistency 265. lvlelting point 1l5l125 F.; A.S.T.M. consistency-210.

4 Melting point ll25 F.; A.S.T.M. consisteucy-2l0.

Theabove data show that excellent lubricants having characteristics that make them especially desirablei'as twister ring lubricants can be prepared in accordance with the teachings of this invention. More specifically, the data show lubricants having built in extreme pressure and high dropping point properties can be obtained by the dispersion of relatively small amounts of hydrous mixtures of alkaline earth metal salts of low and intermediate molecular weight carboxylic acids.

The data further show that when especially low percentages of the metal salts are employed, as in greases C and D, eifective lubricating compositions can only be achieved by melting the petrolatum and finishing the lubricant by homogenization (see grease D).

To further show the advantages afiorded by the lubricant compositions prepared in accordance with the invention, the following data clearly demonstrate the improved wear resistant properties achieved by thickening the desired petrolatum with hydrous mixtures of alkaline earth metal salts of low and intermediate molecular weight monocarboxylic acids.

Comparative tests of the extreme pressure properties of lubricant compositions previously employed by the art and the lubricants of the invention were run on a four-ball extreme pressure tester. Three bronze balls and 1 steel ball were employed under the standard conditions of 2.5 kilogram load, 1800 r.p.m., 75 C. for half an hour. See Boner, Manufacture and Application of Lubricating Greases (Reinhold Publishing Corp., New York, 1954), pages 867 to 869, for a detailed description of this test. The data obtained are set forth in the table below;

Table 11 FOUR-BALL WEAR TEST DATA Scar diameter, mm. (1) Grease B (Table I) 0.23

3. The composition of claim 1 wherein said metal constituents are alkaline earth metals.

4. The composition of claim 1 wherein said low molecular weight carboxylic acid is acetic acid.

(2) Mixed base Sodium ca1cium Soap thickened 5 5. The composition of claim 1 wherein said intermepetmlatum 0 58 diate molecular weight carboxylic acid is caprylic acid. (3) gg T E Z; g g 030 6. A twister ring lubricant composition comprising a 13 1 th 1 h 1 1 t f 18 000 to 90 000 major amount of petrolatum and about to weight prepfied gt l lg lii lsuisf a W 0 d 10 percent of a hydrous mixture of calcium acetate and cal- In an actual operation wherein twister rings were cium caprylate in which the mol ratio of acetic acid to lubricated with grease B, representative of the inventive Capryhc acld. radlcals 1S m the range of about 5:1 composition, and polyethylene thickened petrolatum, de 3011- scribed in Table II above, the following results were The cofnposltlon 0136131111 6 wherein Sald petrolatum bt i d; 15 has a droppmg point within the range of about 110 to Table III Hrs. in No. of Gross Wt. WtJ LossinWtJ Wt. Loss/ Lubricant 0pera- Travel- (gms. of Traveler Traveler Traveler/ tion ers 9 Travelers) 5.) (gms.) Hour (1) Polyethylene thickened petrola- {(new) 144 986553 0. 6851 1 144 192 127.2600 0. 6628 0. 0223 1. s 10- (2) Grease B (Table I) {(uew) 51 30. 1830 0. 5918 348 182 100.7212 0. 5863 0. 0045 1.3 10- 1 Described in Table II. 5 Bronzetravelers.

The data in the above table shows that the twister ring lubricant of the invention reduced the traveler wear to one tenth of that resulting from the use of a conventional twister ring lubricant in an actual thread twisting operation.

In brief summary, it has been found that efiective twister ring lubricants can be prepared by thickening petrolatum to a grease consistency by a cold sett method with hydrous mixtures of metal salts of low molecular weight monocarboxylic acids having from about 1 to 3 carbon atoms per molecule and intermediate molecular weight monocarboxylic acids having from about 7 to 10 carbon atoms per molecule. At least some and usually all water of reaction remains in the lubricating compositron.

The invention is not limited to the specific conditions and materials of the foregoing examples. These conditions and materials may be varied within the limits indicated in the general portions of the specification.

What is claimed is:

1. A twister ring lubricant composition comprising a major amount of petrolatum and 5 to weight percent of a hydrous mixture of metal salts of low molecular weight carboxylic acids having from about 1 to 3 carbon atoms per molecule and intermediate molecular weight carboxylic acids having from about 7 to 10 carbon atoms per molecule and wherein the molar ratio of low to intermediate molecular weight acid salts in said hydrous mixture is about 2:1 to about :1.

2. The composition of claim 1 wherein said petrolatum has a dropping point within the range of about 75 to 135 F. and an A.S.T.M. consistency of about 160 to 275 mm./10.

F. and an A.S.T.M. consistency of about 200 to 275 mm./ 10.

8. A method for preparing a twister ring lubricant composition containing 5 to 30 weight percent of a mixture of metal salts which comprises melting a major proportion of petrolatum, dispersing a metal base in said melted petrolatum, adding to said dispersion a blend of low molecular weight carboxylic acids having from about 1 to 3 carbon atoms per molecule and intermediate molecular weight carboxylic acids having from about 7 to 10 carbon atoms per molecule and then cooling to obtain said lubricant composition, said metal base being present in sufiicient amounts to saponify said acids and said molar ratio of low to intermediate molecular weight acid is about 2:1 to 40:1.

9. The method of claim 8 wherein said metal base is an alkaline earth metal base.

10. The method of claim 8 wherein said low molecular weight carboXylic acid is acetic acid and the intermediate molecular weight carboxylic acid is caprylic acid.

11. The method of claim 8 wherein said lubricant composition is finished by being homogenized at high rate of shear within the range of about 50,000 to 500,000 reciprocal seconds.

References Cited in the file of this patent UNITED STATES PATENTS 2,274,675 Earle Mar. 3, 1942 2,393,797 Morgan Jan. 29, 1946 2,457,586 McGrogan Dec. 28, 1948 2,604,452 Morway et al July 22, 1952 2,735,815 Morway et a1. Feb. 21, 1956

Claims (1)

1. A TWISTER RING LUBRICANT COMPOSITION COMPRISING A MAJOR AMOUNT OF PETROLATUM AND 5 TO 30 WEIGHT PERCENT OF A HYDROUS MIXTURE OF METAL SALTS OF LOW MOLECULAR WEIGHT CARBOXYLIC ACIDS HAVING FROM 1 TO 3 CARBON ATOMS PER MOLECULE AND INTERMEDIATE MOLECULAR WEIGHT CARBOXYLIC ACIDS HAVING FROM ABOUT 7 TO 10 CARBON ATOMS PER MOLECULE AND WHEREIN THE MOLAR RATIO OF LOW TO INTERMEDIATE MOLECULAR WEIGHT ACID SALTS IN SAID HYDROUS MIXTURE IS ABOUT 2:1 TO ABOUT 40:1.