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A high speed road test procedure was developed to demonstrate performance of multigrade engine oils in journal bearing wear protection. High shear viscosities of test oils were approximated through use of a pump loop. A reasonable first approximation of critical viscosity for bearing failure is estimated by measurements at 149°C and about 5Xl05 sec -1 with the pass/fail limit being about 3.5 cSt.

A new concept in unsaturated polyester resins now provides exceptionally smooth surfaces on molded glass fiber reinforced structures. The resins have good cure speed and contribute to excellent strength retention of molded parts at elevated temperatures. Premix compounds based on low shrink resin are well suited for injection molding because of an unusual combination of attributes. The use of these unique resins will offer reduced finishing costs for glass mat reinforced moldings and open new “appearance” applications for the versatile premix molding process.

Low temperature engine oil pumpability studies were conducted using a motored Cummins NTC-400 heavy duty diesel engine set up in a cold room. Comparative performance data were obtained for new SAE 15W-40 and SAE 10W-30 engine oils based on polymethacrylate, olefin copolymer and hydrogenated styrene-diene VI improvers. In addition, used oils from line-haul fleet tests were also investigated. Pumpability tests were conducted at 1800 rpm over a temperature range from -1°C (30°F) to -21°C (-5°F) to determine oil flow times, time to achieve pressurization, and the suitability of the MRV test method, ASTM D 4684, to predict engine borderline pumping temperature (BPT). The study revealed that selection of VI improver plays a significant role in low temperature pumpability performance. The polymethacrylate oils provided the lowest engine BPT and fastest oil flow.

Low temperature engine oil pumpability studies were conducted using a motored Cummins NTC-400 heavy duty diesel engine set up in a cold room. Comparative performance data were obtained for SAE 15W-40 engine oils based on polymethacrylate, olefin copolymer and hydrogenated styrene-diene VI improvers. Pumpability tests were conducted at 1800 rpm over a temperature range from -1°C (30°F) to -21°C (-5°F) to determine oil flow times, time to achieve pressurization, and the suitability of the MRV test method, ASTM D 4684, to predict engine borderline pumping temperature (BPT). The study revealed that selection of VI improver plays a significant role in low temperature pumpability performance. The polymethacrylate oils provided the lowest engine BPT and fastest oil flow. Oil pressure instability at low temperature appeared to be caused by air entrainment, and was significantly affected by the choice of VI improver.

Optical fibers for distributive lighting systems must exhibit high transparency and accurate color rendition. These properties must also be maintained after extended use. The SAE Distributive Lighting Task Force is defining the mechanical, optical, and chemical durability specifications for exterior applications, the most demanding of which is forward lighting. We have developed methods to test the stability of plastic optical fibers to heat, to light, and to combinations of heat and light. When plastic optical fibers fail, it is due to a color temperature shift rather than to a loss in transparency. That is, the light that the fiber or light pipe transmits shows a noticeable color change before its intensity is diminished significantly. The goal is to minimize the color temperature shift from the high-intensity discharge (HID) light sources. Our durability test methods monitor these color changes of transmitted light.

Developing engine oil formulations for today's marketplace requires a careful balance between cost and performance. Definition of optimized formulations requires detailed knowledge of the quantitative relationships between performance, or deposit control, and additive component concentrations. To develop these relationships, a series of multigrade engine oils formulated with two levels of a dispersant olefin copolymer VI improver were evaluated using the Caterpillar 1H2 engine test procedure. The performance package components and/or their levels in these oils were varied according to statistically designed, fractional factorial patterns. This approach provides an estimate of the effect of each component and their interactions. It also provides insight into the inherent test variability associated with TGF, WTD and the land and groove deposits which make up these ratings.

Temporary shear loss characteristics of multigraded engine oils were measured in a newly developed engine oil pump rig. Correlations of the results with high pressure capillary viscometry data indicate that the test apparatus generates shear rates in the range of 2-3 × 105 s-1. One advantage of this technique over similar mechanical approaches is that the test rig causes virtually no permanent shear degradation. Test results are reported for a variety of polymer types, and the relationship of permanent and temporary shear losses is discussed.