Note: Descriptions are shown in the official language in which they were submitted.
~221677
EXTREME PRESSURE ADDITIVE FOR USE IN METAL LUBRICATION
BACKGROUND OF THE INVENTION
1. Field of the Invention
-
This invention relates generally to the field of lu-
bricant additives, and more specifically relates to the
field of extreme pressure additives suitable for addition
to motor oils.
2. Description of the Prior Art
It is known that certain chlorine-based compounds,
such as those chlorine derivates of paraffin compounds re-
ferred to as chlorinated paraffins, can serve as lubricant
additives to improve the performance of the lubricant under
extreme pressure. Under normal lubricating conditions, the
two metal surfaces will be separated by a thin film of lu-
bricant which provides the required reduction in friction.
Under situations of extreme pressure between the two metal
surfaces, all the liquid lubricant is forced from the area
of contact between the surfaces. Where an extreme pressure
additive such as chlorinated paraffin is present, however,
it has been found that the resultant heat generated between
the two surfaces causes chlorine atoms to be liberated from
the additive and to combine with the surface metal, such as
iron, to form a chloride, such as iron chloride. This sur-
face coating of chloride has a much lower coefficient of
friction than the dry metal surface. The iron chloride
surface coating tends to fill in depressions in the surfa-
ces, resulting in smoother surfaces at the point of inter-
action and reduced friction and wear.
Chlorinated paraffins have been used as extreme
pressure additives in such applications as metal-working.
However, the corrosive nature of chlorinated paraffin has
made it generally unsuitable for use in internal combustion
lZ2~1~i77
engine applications or other corrosion-sensitive applica-
tions. Under heating, the chlorinated paraffins release
hydrochloric acid, which is corrosive.
SUMMARY OF THE INVENTION
The present invention provides an extreme pressure
additive largely composed of chlorinated paraffins but
having reduced corrosive properties. It is therefore sui-
table for use in internal combustion engine lubricants orother applications where corrosion must be avoided.
According to one aspect of the invention, there is
provided an extreme pressure lubricant additive comprising
a major amount of chlorinated paraffin and a minor amount
of an alkaline earth metal sulfonate, preferably calcium
sulfonate. A mineral oil, with or without mineral spirits,
may be used as a base oil for the additive. In one aspect
of the invention the additive comprises between thirty and
seventy volume percent chlorinated paraffins and from .5 to
10 percent by volume calcium sulfonate. According to a
further aspect of the invention, the additive comprises
approximately 55 volume percent chlorinated paraffins,
approximately 32 volume percent of a mineral oil, approxi-
mately 10 volume percent of mineral spirits and approxi-
mately 3 volume percent of a calcium sulfonate. Further
according to the invention a lubricant suitable for use as
a motor oil in internal combustion engines is provided by
adding one part of the above extreme pressure lubricant
additive to between 10 and 30 parts of standard motor oil.
According to a preferred aspect of the invention, approxi-
mately one part of the extreme pressure additive is added
to twenty parts standard motor oil. Also according to the
invention, the above extreme pressure lubricant additive
may be added to various greases, automatic transmission
fluid, air-conditioner freon or penetrating oil to improve
the extreme pressure performance of such lubricants.
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According to a further aspect o:E the invention, the extreme
pressure lubricant additive may be added to gasoline or
diesel fuel conditioners to provide an improved gasoline or
diesel fuel conditioner.
Further according to the invention there is provided a
method of producing an extreme pressure additive for lubri-
cants comprising the steps of:
a) blending a chlorinated paraffin in an amount approxi-
mately 55 percent by volume of the final product with
a base mineral oil in an amount approximately 32 per-
cent by volume of the final product at an elevated
temperature of approximately 150 degrees fahrenheit;
b) mixing a calcium sulfonate in an amount approximately
3 percent by volume of the final product with mineral
spirits in an amount approximately 10 percent by vol-
ume of the final product; and
c) blending the chlorinated paraffin/mineral oil mixture
with the calcium sulfonate/mineral spirits mixture at
an elevated temperature of approximately 150 degrees
fahrenheit.
DE LED DESCRIPTION OF A PREFERRED EMBODIMENT
The preferred form of chlorinated paraffin used in the
present invention is the product marketed by C-I-L Inc.
under the trade name CERECLOR* 42 which has a stated mole-
cular formula of C15.5H26.8C116.31- (The
product is known to be mildly corrosive in contact with
steel and to decompose into hydrochloric acid and hydrogen
chloride). The chlorinated paraffin in an amount approxi-
mately 55 percent by volume of the final additive product
is mixed with a base mineral oil in an amount approximately
32 percent by volume by blending thoroughly at slow speeds
to avoid foaming while heating the mixture to approximately
150F. The heating promotes the mixing process and pre-
*trade mark
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vents subsequent separation of the constituent components.A preferred mineral oil is marketed by Shell Canada Limited
under the trade name VITREA* No.32. The calcium sulfonate
is next mixed separately with mineral spirits. The prefer-
red proportion is approximately 3 percent calcium sulfonateby volume of the final additive product, and approximately
10 percent by volume of the mineral spirits. The preferred
product for the calcium sulfonate is marketed under the
trade mark LU~RI20L* 78 by the Lubrizol Corporation. It is
a highly basic calcium sulfonate, approximately 400 TBN
having a calcium weight percent between 15.0 and 16.0 and a
sulfur weight percent between 1.25 and 1.8. The preferred
mineral spirit product is marketed by Shell Canada Limited
under the trade mark SHELL SOL* and has a composition of
89-94 percent by volume of saturates, and 6-15 percent by
volume aromatics, and a maximum 0.1 percent by volume sul-
~ur.
The calcium sulfonate/mineral spirits mixture is then
blended with the chlorinated paraffin/mineral oil mixture
at a temperature of approximately 150F. The blending
should be done so that the product is not permitted to
foam. Again, failure to properly blend the ingredients at
the elevated temperature may result in crystallization or
sedimentation of the components. The result of this final
blending process is the extreme pressure additive of the
invention.
The characteristics of the additive of the invention
have been tested with the following results:
Gravity at 60F 6.2 API
Viscosity @ 100F 659 SSu or 142.2 cST
Flash Point C.O.C. 310F or 155C
35 Moisture ASTM D95 0.08% by weight
* trade marks
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Copper Strip Corrosion
1 hour @ 100C Pass
Pour Point -13~E or -25C
Compatability:
ESSO UNIFLO* 10~40 Vis. 100F: 415.9 SSU 89.7CST
with 6% of the invention 410.8 SSU 88.6cST
CASTROL* + or - zero/40 409.7 SSU 88.4CST
with 6~ of the invention 407.7 SSU 88.0CST
TEXACO URSA* 30 560.1 SSU 120. 8CST
with 6% of the invention 556.7 SSU 120.1cST
The invention showed good compatability with all three
standard types of motor oil. To test corrosion loss, mild
steel blanks were left in the product for seven days at
between 210F and 220F. When left in ESSO UNIFLO* 10/40
oil, there was no corrosion loss measured. When the addi-
tive of the invention was added in the amount of 6 percent
by volume to the UNIFLO* there again was no corrosion loss
measured.
The effectiveness of the invention as an extreme pres-
sure lubricant can be readily demonstrated using an extreme
pressure testing machine. This machine utilizes an elec-
tric motor to rotate a steel bearing race. A stationary
steel bearing is brought into contact with the rotating
bearing race. This done by removably inserting the bearing
into the end of a rotating arm which is allowed to rest in
contact with the rotating bearing. The arm is in turn le-
vered by a second rotating arm to the end of which weights
may be applied. The effect of the arrangement of the arms
is to provide a multiple lever effect so that a small
weight applied to the end of the latter arm is greatly mag-
nified through the principle of the lever through to the
* trade marks
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~ZZ1677
point of contact with the rotating bearing race. Because
of the small area of contact, a very great pressure is
applied by ~he stationary bearing to the rotating bearing
race. The bearing race is initially allowed to rotate in a
bath of a standard motor oil, and the end of the arm with
the test bearing is allowed to rest on the rotating race
without additional pressure. On examination of the test
bearing, it is found that a small scar, approximately one
millimeter in width is formed in the surface of the bearing
due to the friction. The test bearing is then rotated to
apply a fresh surface to the bearing race, and again the
test bearing is allowed to contact the rotating race only
this time a weight of approximately four pounds is applied
to the end of the multiple-lever apparatus to apply more
pressure to the point of contact. Upon examination of the
test bearing, a large scar has been formed in the surface
of the bearing, approximately four millimeters in width.
The procedure is then repeated, only an amount of the
extreme pressure lubricant additive of the invention is
added to the motor oil bath in which the bearing race is
rotating. Again, the test bearing is rotated to present a
fresh surface to the bearing race and is allowed to rest in
contact against the rotating race without additional pres-
sure. Upon examination of the test bearing, it is foundthat the initial amount of scarring has been greatly re-
duced. When the test is repeated with a four pound weight
at the end of the lever mechanism, the scarring is still
less than was present in the initial oil-only situation
without additional pressure, with the scar now being less
than one millimeter in width. Indeed, rather than being a
deep gouge out of the surface of the bearing, as was the
case with the oil-only bath, the point where the test bear-
ing contacted the bearing race rotating in the oil-plus-
additive bath appears to the eye to be a small polishedarea on the surface of the bearing. Even if the weight at
the end of the lever mechanism is increased by a factor of
122~6~7
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six from the four pound weight, the size of the scar on the
test beariny does not increase significantly and still is
not significantly greater in width than was the case in the
oil-only bath situation where no additional pressure was
added. Indeed, the surface of the scar is shown to be
polished compared to the pitted scar present in the oil-
only situation.
In addition to serving as an extreme pressure additive
for motor oils, the lubricant additive of the invention may
also be added to other lubricants and fluids such as grea-
ses, (where approximately 10 percent by volume of the addi-
tive is preferred), metal cutting lubricants, hydraulic
oils (excluding hydraulic brake fluid), automatic transmis-
sion fluid, power steering fluid, penetrating oil, air-
conditioner freon, and as a coating for brass. In all
these applications, the additive of the invention serves to
rsduce friction and metal wear under extreme pressure situ-
ations, and also serves to reduce corrosion. It has also
been found that by adding the extreme pressure additive
product of the invention to a gasoline or diesel fuel con-
ditioner, the performance of the internal combustion engine
is improved through lubrication of the moving metal parts
which come into contact with the fuel in the upper end of
the engine.
While calcium sulfonate has been specified as the
appropriate sulfonate to counteract the corrosive proper-
ties of the chlorinated paraffins, other alkaline earth
metal sulfonates having similar properties would also be
suitable for use in the invention. While a preferred embo-
diment of the invention has been described, the scope of
the invention should not be limited thereto but is defined
by the following claims.
