Patent Application
20080090741
Three different lubricant compositions: A, B, and C were formulated as shown in Table 1. A and B were formulated with similar dispersant/detergent inhibitor (DI) systems, but with different mixtures of base fluids. B and C were formulated with similar base fluids, but with different ratios of overbased detergent to low-base detergent.
Table 2 provides the elemental analysis of the three formulations.
The three formulations, A, B, and C as described in Table 1 were subjected to the Sequence IIIG test to measure oil thickness and piston deposits under high temperature conditions and to provide information about valve train wear. Table 3 show the results of the Sequence IIIG tests.
As can be seen from Table 3, A and B passed the Sequence IIIG requirements for GF-4/SM, but failed to meet the more stringent WPD performance (WPD at 5.5 minimum) for GM4718M. Further it is to be noticed that C performed better than B with respect to the WPD. Because B and C were formulated with basically the same mixture of base fluids, but with different ratios of overbased detergent to low-base detergent, the better performance of C can be attributed to the different mixture of overbased and low-base detergent. Table 2 further shows elemental analysis of the three formulations A, B, and C. It should be noted that while A and B have the same ratio of salt to metal, C has a higher value.
At numerous places throughout this specification, reference has been made to a number of U.S. patents, published foreign patent applications and published technical papers. All such cited documents are expressly incorporated in full into this disclosure as if fully set forth herein.
For the purposes of this specification and appended claims, unless otherwise indicated, all numbers expressing quantities, percentages or proportions, and other numerical values used in the specification and claims, are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
It is noted that, as used in this specification and the appended claims, the singular forms “a,” “an, ” and “the,” include plural referents unless expressly and unequivocally limited to one referent. Thus, for example, reference to “an antioxidant” includes one or more different antioxidants. As used herein, the term “include” and its grammatical variants are intended to be non-limiting, such that recitation of items in a list is not to the exclusion of other like items that can be substituted or added to the listed items.
This invention is susceptible to considerable variation in its practice. Therefore the foregoing description is not intended to limit, and should not be construed as limiting, the invention to the particular exemplifications presented hereinabove. Rather, what is intended to be covered is as set forth in the ensuing claims and the equivalents thereof permitted as a matter of law.
Applicant does not intend to dedicate any disclosed embodiments to the public, and to the extent any disclosed modifications or alterations may not literally fall within the scope of the claims, they are considered to be part of the invention under the doctrine of equivalents.
