US2693450A - Wire rope lubricant comprising a blown residuu, a petroleum wax, and a light chlorinated hydrocarbon - Google Patents

Description

United States Patent Roy F. Nelson, Port Arthur, Tex., assignor to The Texas Company, New York, N. Y., a corporation of Delaware No Drawing. Application February 5, 1952, Serial No. 270,109

8 Claims. (21. 252-544;

This invention relates to an improved lubricating and preservative composition, and more particularly to a wire rope lubricant of the compound asphaltic type containmg a light chlorinated hydrocarbon which is capable of belng applied at room temperatures without heating.

Wire ropes are lubricated during manufacture and use 1n order to protect them from deterioration resulting from exposure to the atmosphere and other detrimental elements and to reduce frictional wear. According to a conventional practice, the wire rope is made by twisting a number of wires together and drawing the resulting twisted strands through a die, with a steady stream of the lubricant being applied to the twisted strands just before they pass through the die. For proper lubrication of the rope, the lubricant must penetrate into the strands and surround each wire with a lubricating film of suificient thickness and film strength to prevent metal to metal 1 contact when the wires moves against each other under high pressure, which occurs when the rope passes over a drum or pulley wheel under a heavy load. In addition, the lubricant must form a smooth adherent film on the outside of the rope which is resistant to wiping off and to displacement by water. It is furthermore very important that the lubricant retain its plasticity at low temperatures, as otherwise it will become brittle and flake off when the rope is handled in cold weather.

to which wire ropes are exposed in service, neither run ning off the wires at high temperatures nor losing its plasticity and adhesiveness even at very low temperatures.

The asphaltic material employed is obtained from a heavy residuum of predominantly parafiinic character having a viscosity (Saybolt Universal) in the range of about 100-140 seconds at 210 F., and most suitably of about 120 seconds at 210 F. This material is blown with air at an elevated temperature according to conventional procedure, for example at a temperature in the range of about 450525 F. forabout 24-36 hours, until a product is obtained having a softening point in the range of about l20- -150 F., and preferably of about 130-135" F.

The light chlorinated aliphatic hydrocarbon is suitably a stable, non-corrosive compound having a boiling point within the range of about 125-2l0 F., and preferably about 150-200 R, such as for example carbon tetrachloride, dichloroethylene, trichloroethylene and l-chloro- 2-butene. Most advantageously, it is a light chlorinated olefinic compound wherein the chlorine atoms are attached to the double bond carbon atoms. Trichloroethylene is regarded as the preferred compound of this class for use in the compositions of my invention. These compounds may be employed in amounts ranging from about 5 to 25 per cent, and most suitably from about 10 to 20 l per cent by weight of the lubricating composition.

The most generally satisfactory lubricating compounds for wire rope lubrication available heretofore have been normally solid asphaltic compositions, which require heat ing for their application. However, heating is very inconvenient to employ, and the coatings thus applied tend to be deficient in spreading and penetrating properties. Compositions containing solvents such as light hydrocarbons which have been employed, are generally lacking in ability to remain on the rope in sufficient quantity to form lubricating and preservative films of satisfactory thickness and moreover, such light hydrocarbon solvents increase the hazards of application of a heavier type of lubricant which requires at least moderate heating to attain proper fluidity.

- In accordance with my invention, an improved wire rope lubricant comprises a blend of an asphaltic material obtained by air blowing a residuum from a parafiinic type crude, with a minor proportion of a light chlorinated aliphatic hydrocarbon sufficient to give a product having an ASTM unworked penetration in the range of about l-300 at 77 F. The composition also comprises a minor amount of a structure modifying agent, such as petrolatum, various high polymer materials, waxes, etc., which is incorporated with the blown residuum prior to mixing with the chlorinated hydrocarbon. Other additives such as extreme pressure agents, antioxidants, antirust agents, etc., may also be present if desired.

The composition of this invention is characterized by being readily pumpable at normal room temperatures without heating, while at the same time it forms a satisfactory adherent film on the wire rope without objectionable draining or dripping off upon application. It is also characterized by exceptional spreading and penetrating properties, forming smooth, unbroken films upon the wires when applied by any of the methods ordinarily employed in the manufacture and use of wire ropes. It has superior lubricating and preservative properties as compared with wire rope lubricants of the prior art, including good film strength, adhesiveness and resistance to penetration by water and corrosive gases. It maintains these properties over a wide temperature range of the order The structure modifying agent is preferably a petrolatum, such as obtained by centrifuge dewaxing of paraffinic residuums. This material is employed in amounts ranging from about 5-15 by weight of the composition, and preferably about 742%. Other plastic materials of similar physical characteristics having melting points above about F., such as waxes, synthetic polymers, and the like, can be employed in place of petrolatum for the structure modifying properties.

The lubricating composition of this invention may be readily prepared by mixing together the blown asphaltic material with the light chlorinated hydrocarbon at an elevated temperature, below the boiling point of the latter compound. The blown asphaltic material may be first compounded with a structure-modifying material of the character described above by mixing at an elevated temperature of about 400-450" F. The mixture is then cooled to somewhat below the boiling point of the chlorinated hydrocarbon for incorporation of the latter. The final composition is preferably drawn at a temperature in the range of about -170 F., and most advantageously in the range of about l65 F. I have found that drawing temperatures in this range are optimum for producing a product of the desired consistency characteristics, i. e., a product which is soft enough to pump readily at room temperature but which does not work down excessively so that it becomes liquid when pumped, since such compositions have inferior adhesiveness and ability to cling to the ropes, particularly when applied to ropes being formed in a vertical lay machine. Most desirably, therefore, my lubricating composition has an ASTM unworked penetration at 77 F. in the range of 250 and an ASTM worked penetration at 77 F. below about 350. Table I below shows the effect of the drawing temperature upon the consistency characteristics of a lubricating composition of my invention containing about 9% of petrolatum and about 15% of trichloroethylene in the blown paratlinic residuum:

ASTM Penetration, 77 F.

Drawing Temperature, F.

Unworked Worked As shown by the table, the consistency of the product decreased markedly with increased drawing temperature, the range of about 150-160 F. being optimum for producing the most desirable consistency characteristics with the particular blown residuum used. With drawing temperatures below about 140 F. products having unworked penetrations in the desired range could only be obtained by employing increased amounts of trichloroethylene, which is undesirable since products containing higher proportions of the light chlorinated hydrocarbon, particularly above about 25% by weight, soften to an objectionable degree upon working.

The preferred composition of my invention comprises a blown paraffinic residuum as described above having a softening point of about 130-135 F., with about -15 by weight of petrolatum and about 20% by weight of trichloroethylene. This compound is most suitably prepared by mixing together the blown residuum when it has cooled to about 400-450 F. with the petrolatum, mixing in the trichloroethylene when the temperature of the mass is below about 180 F. and preferably around 160 F., and finally drawing at a temperature of about 14S165 F.

The following example illustrates the preparation of a lubricating composition according to the preferred embodiment of my invention.

EXAMPLE A lubricating compound suitable for use as a wire rope lubricant was prepared from the following materials:

The blown residuum was obtained by air flowing a parafiinic residuum having a Saybolt Universal viscosity at 210 F. of about 180 seconds. The air blowing was carried out at a temperature of 450525 F. for about 30 hours until a product was obtained having a softening point of 132 F.

The petrolatum was obtained by solvent extracting and centrifuging a residual fraction from a parafiinic type crude. It had a melting point of 153 F. and contained about 25% of oil.

The trichloroethylene was a commercial product which is sold under the trade name of Triclene.

In preparing the lubricating compound the blown residuum and the petrolatum were first blended by mixing them together at a temperature of about 430 F., a product being obtained which had a ball and ring melting point of 134 F. and an ASTM unworked penetration at 77 F. of 135. This product was mixed at about 160 F. with the trichloroethylene. The batch was maintained at about this temperature for thirty minutes and finally drawn at about 160 F. A black colored semi-fluid plastic mass was obtained having an ASTM unworked penetration at 77 F. of 188.

The above compound was employed as a w1re rope lubricant by pumping it onto a wire rope being formed in a vertical lay machine. Considerable difficulty has been experienced heretofore in lubricating rope being formed in these machines, since lubricants of the prior art either failed to spread evenly or else they dripped off the ropes, so that uniform coatings of satisfactory thickness were not obtained. The compound of my invention pumped readily at room temperatures and formed a smooth lubricating film of very satisfactory thickness 70 which adhered firmly to the wires and did not drip off. Additional batches of this compound were made up by the method described and field tested very successfully for several months in wire rope lubrication. In addition to the advantage of being conveniently applied, the compound was judged by wire rope manufacturers and users to afford very superior lubrication and protection to the ropes as compared with wire rope lubricants heretofore employed.

Obviously many modifications and variations of the 5 invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof and, therefore, only such limitations should be imposed as are indicated in the appended claims.

I claim:

1. A wire rope lubricant consisting essentially of a blown petroleum residuum from a paraffinic crude oil as the predominant constituent, about 5-15 by weight of petrolatum and about 5-25% by weight of a light chlorinated aliphatic hydrocarbon having a boiling point 15 within the range of about l25-210 F., said lubricant having an ASTM unworked penetration in the range of about 120-150" F.

2. A lubricant according to claim 1 wherein the blown petroleum residuum has a softening point in the range of about ll50 F.

3. A lubricant according to claim 1 wherein the light chlorinated aliphatic hydrocarbon is trichloroethylene. 4. A Wire rope lubricant consisting essentially of a blown paraflinic residuum having a softening point of 25 about 120150 F. containing about 5-15% by weight of petrolatum and about 5-25 by weight of trichloroethylene.

5. A wire rope lubricant consisting essentially of a blown paraifinic residuum having a softening point of about 130135 F. containing about 5-15% by weight of petrolatum and about 1020% by weight of trichloroethylene.

6. The method of preparing a wire rope lubricant which comprises mixing a blend of a major proportion of a blown parafiinic residuum having a softening point of about -150" F. and about 5-15% by weight based on the final lubricant of petrolatum, with about 525% by weight based on the final lubricant of a light chlori- .nated aliphatic hydrocarbon having a boiling point in 40 the range of ISO-200 F. at an elevated temperature above the softening point of the residuum blend but below the boiling point of said chlorinated hydrocarbon, and drawing hte product at a temperature in the range of about 170 F.

7. The method of preparing a wire rope lubricant which comprises mixing together a blown paratfinic residuum having a softening point of about 120150 F. and about 515% by weight based on the final lubricant of petrolatum at a temperature of about 400-450 F., cool- 5() ing the obtained mixture to about 160170 F., mixing it with about 10-20% by weight based on the final lubricant of trichloroethylene, and drawing the product at a temperature in the range of about -165 F.

8. A wire rope lubricant consisting essentially of a 55 blown petroleum residuum from a paraffiuic crude oil as the predominant constituent, about 515% by weight of a petroleum wax having a melting point above about 135 F., and about 5-25% by weight of a light chlorinated aliphatic hydrocarbon having a boiling point within the 0 range of about 1252l0 F., said lubricant having an ASTM unworked penetration in the range of about -300 at 77 F.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,166,173 Montgomery July 18, 1939 2,211,254 Chittick Aug. 13, 1940 2,237,682 McLennan Apr. 8, 1941 2,258,930 Haefner Oct. 14, 1941 2,453,094 Killingsworth Nov. 2, 1948 OTHER REFERENCES Industrial Solvents, Mellan, 2nd ed. 1950, Reinhold gub. (50., pp. 311, 335 and 336. (Copy in Scientific Lirary.