US1982198A - Lubricant - Google Patents

Description

Patented Nov. 27, 1934 UNITED STATES LUBRICANT Lawrence C. Brunstrum, Chicago, Ill., and Maurice Schmidt, Hammond, Ind.,

assignors to Standard Oil Company, Chicago, 111., a corporation of Indiana No Drawing. Application January 5, 1932,

' Serial No. 584,892

3 Claims.

This invention relates to a'lubricant insoluble in naphtha and other hydrocarbons and it pertains more particularly to a plug valve lubricant.

The object of our invention is to provide a plug valve'lubricant with improved covering properties, one that will adhere tenaciously to surfaces on which it is applied. A further object is to provide a lubricant with improved sealing properties, one that will withstand high pressures for an extended period of time without being displaced or blown out. A further object is to provide a lubricant of this type that will have a workable consistency, one that may be re-worked after it has been allowed to stand, and one which will not disintegrate or leak on standing. A further object is to provide a lubricant which will be non-corrosive and insoluble in hydrocarbon solvents. T

A feature'of the invention is the provision of a lubricant in stick form which is readily workable and in which the stiffness is dependent upon the presence of solids or solid solutions as dis tinguished from the presence of emulsions. It is essential that lubricants of this type have a workable consistency and a relatively high melting point, preferably upwards of 125 F. Heretofore greases with the proper consistency have had too low a melting point to be practical, and greases having the proper melting point were too hard. We have discovered that by using acids from certain hydrogenated fatty oils we obtained abnormally and unexpectedly high melting points for a given lubricant consistency.

Another feature of our invention is the use of about 50% or more of glycerin in a stable stick composition of gel-like structure. If the composition consisted merely of glycerin and the soap of an acid from hydrogenated fatty oils, the glycerin would come to the surface of the composition, or, to use the expression common in the art, it would leak out of the lubricant. Also, parts of the composition might become unduly hard or tend to form a crust. We have discovered that by incorporating suitable quantities of soda rosin soap in the composition we eliminate the tendency of the glycerin to leak therefrom and at the same time we add considerably to the tackiness or adhering qualities of the lubricant. Other features will be apparent from the following detailed description:

A preferred formula is as follows:

' Per cent Sodium soaps of acids of hydrogenated fatty oils 20 Soda rosin soap 18 Water 12 Glycerin This formula, however, may be varied within the following range:

a Per cent Sodium soaps of acids of hydrogenated fatty oils 10110 26 Soda rosin soap 9to 24 Water 6 to 16 5 Glycerin 35 to In making'up 100 lbs. of our preferred formula we use the following ingredients:

The method of making this grease is relatively simple and it requires no special precautions. The glycerin and caustic are first poured into a mixer and heated to about 100 to 200 F., after which the acid of hydrogenated fatty oils is added with stirring, which stirring is continued until saponification or neutralization is completed. When the temperature falls to about 200 F. the soda rosin soap is stirred into the mixture. The finished product is a clear light brown plastic substance which may be readily pressed into sticks of any convenient size. The consistency is such that the composition may be exuded through an orifice in the form of soft resilient sticks, the surfaces of which are coated by dusting with powdered mica or similar inert powder.

In some cases it may be desired to incorporate a filler or solid lubricant, such as graphite, talc, or mica, into the mixture, andthis may be done without departing from the invention;

As hereinabove stated a feature of our invention is the high melting point which we obtain for any given consistency. This will be brought out in the following table, showing results obtained when our preferred formula was made up with different acids and the resulting lubricants were subjected ix) comparative hardening point (or melting point) tests and consistency (or penetration) tests.

For a lubricant of this type it is essential that the penetration be about 20 or within the range of 15 to 30. It is also essential that the melting point be higher than 125 F. It will be observed from the above table that the lubricant prepared from the low titre acid from hydrogenated fatty oils is unique in that it has a 'far greater penetration, and at the same time a much higher melting point than can be obtained with. .the best fatty acid from the usual source (stearic acid). If the consistency of the stearic acid lubricant were adiusted to have a penetration of 20, the hardening point of the grease, or melting point, would be far below 125.F. 0n the other hand the last lubricant in the list could be made softer without depressing its melting point below 125 F.

The acids from hydrogenated fatty oils are well known in the fatty acid art and they need no detailed description. The low titre acid is made by splitting a hydrogenated oil mixture prepared by hydrogenating fish oil with the addition of some cotton seed oil. Generally speaking, animal oil such as fish oil, lard oil, etc., and vegetable oils, such as cotton seed oil, rapeseed 011, corn oil, etc., may be lwdrogenated and these hydrogenated oils may be split to form the acids which are used in our invention. The acids are chiefly saturated 18 carbon chains, higher titres being obtained by choosing oils having small amounts of 20 and 22 carbon atom chains. Acids from hydrogenated oil should theoretically have about the same characteristics as pure stearic acid, but as shown by the above results, the acids from hydrogenated ofl have a peculiar effect upon the properties of the lubricant'in which they are incorporated. It

rated 18 carbon acids as exemplified by thou may be that commercial stearic acid is unsuitable because of the oleic acid (17 carbon atoms) usually contained therein. We do not limit ourselves as to any theories as to the difference between commercial stearic acid and acid from hydrogenated oils, but we contemplate the use of satu- Droduced from hydrogenated oils.

lubricant, and in many cases direct saponiflcation of hydrogenated fats is desirable.

Another feature of our invention is the use of soda rosin soap in this particular combination.

M This ingredient imparts atackiness .or adhering power to the lubricant which is very desirable and at the same time it prevents the glycerin from leaking out of the lubricant. Heretofore, lubricants of this type have contained far less glycerin and far more soap than is called for by our formula,,and it has been impossible to obtain the workability, stability, and high melting points which characterize our product.

In compositions ofthis type it is difficult to dehydrate glycerin completely and to a certain extent the water and glycerin play a similar role.

The term "glycerin" as used in the following claims is therefore defined as glycerin which may contain a small amount-of water, the percentage including both the glycerin and the water. It should be underst00d,'of course, that glycol and other equivalent substances, particularly polyhydric alcohols, may be used in place of glycerin and the term "glycerin" in the appended claims is intended to include glycol and equivalent substances.

While we have described a preferred embodiment of our invention, we do not limit ourselves to the details set forth except as defined by the following claims, which should be construed as broadly as the prior art will permit.

We claim: a I

:1. A lubricant having about the following for m a:

' Per cent Glycerin 45 to 8 0 Soap of acid from hydrogenated oil. 10 to 30 Boda rosin soap 10 to 25 2. A lubricant-comprising about the following formula: v

.3. A plug-valve lubricant whichwill adhere to surfaces on which it is applied, which will maintain a seal under high pressures for an extended period of time, which will have'a workable consistency after standing for an extended period of time, and which can'be used in systems employing hydrocarbon solvents, which lubricant comprises about 45-80% of glycerin, 10-30% of a soap prepared from an acid splitf'rom' a hydrogenated oil, and 10-25% of soda rosin soap.

LAWRENCE c. BrtUNs'mUM. MAURICE ascnmnr;