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This paper presents the rationale and underlying logic for automatic transmission filtration contaminant control (ATFCC). This approach relies upon an integrated filtration system as opposed to simply sandwiching in a piece of filter media or metal screen in the traditional transmission oil sump area. Most significantly, quantitative filtration system design and specification will result from implementation of a thorough ATFCC approach. A new transmission filter test procedure is also presented which closely represents the field operation of these types of filters. Test results are presented which compare the new test procedures results' with more traditional Multipass Filter test results.

The increasing focus on automotive automatic transmission contamination levels needs to result in both dramatic manufacturing system changes and transmission filtration needs. This paper focuses on defining and quantifying automatic transmission contaminant levels and the filtration needed to remove this contaminant. Specific data are presented which quantify the particle count and gravimetric level of transmissions oil samples. The debris found from numerous used filter analyses is also presented. Representative transmission valve contaminant sensitivity data is then shown which highlights the deleterious effect contaminant has on transmission valve operation. This paper concludes with the particle removal efficiency of common transmission sump filters being shown to be unable to remove many of the most damaging particles which result in transmission valve sticking, wear, and general shift quality degradation. Recommendations for correcting this situation are presented.

Conventional practice is for automotive engine lubrication filter designers to include many devices in a typical “spin-on” filter. These include the filter element housing, tapping plate, and internal components, such as, an anti-drainback valve, the filter element structural support, the filter media and in some cases, the safety relief valve. Understanding the interaction of all these components before a prototype is built greatly aids in achieving a functional, cost effective solution to meet required flow and pressure drop, filtration efficiency, and contaminant capacity requirements for a particular filter. Furthermore, the investment in modeling a specific filter design enables variations or modifications to be made to the original design very easily and at little cost. This paper presents a detailed mathematical flow model that was developed for a new type of dual flow filter.

Diesel engine lubricant filtration is relied upon to protect critical engine components against wear. The type of filtration and the efficiency of particle removal is vital to minimizing engine wear. This paper presents the results of a comprehensive study which characterized the correlation between engine dynamometer tests and eight different engine filtration configurations. The experimental filtration schemes were exhaustively tested according to the well known multipass test procedure, SAE J1858. A low level Surface Layer Activation (SLA) radioactive spot was deposited at six points throughout the tested engine. Controlled, pressurized 0-30 micron test dust in an engine oil suspension was injected into the test engine under prescribed conditions and the progressive wear was measured at all the six points for four of the experimental filtration setups.

Rapid development of automotive fuels has occurred in the past ten to fifteen years resulting in reformulated and alternative liquid fuels together with a myriad of fuel additives aimed primarily at improving combustion and tail pipe emissions. Many of these changes have had significant but unreported or unmeasured effects on the physical properties of the fuels. This paper presents the details of a program which sought to characterize the lubricity (or antiwear) characteristics of known gasoline formulations with a bench top assessment test machine and to correlate these results to actual fuel pump wear debris generation tests.

The focus of this paper is the interpretation and application of the Multipass Filter test- more commonly known as the Beta test for determining a filters (or medias) Beta Rating. A specific Beta test report is deserved and analyzed. A review of the required test equipment for conducting a Multipass test is provided and many test operating conditions are described. The Beta Rating definition and detailed points for conducting a Beta test are also given.

The understanding of a filter's performance is often not only confusing but misleading. Automotive filters, for this discussion referring to engine lubrication filters, transmission fluid filters, and fuel filters, are no exception. Advanced filtration assessment techniques have been finding increasing use and application in many filter specifications for OEM and aftermarket use. This paper addresses the application of laboratory filter assessment methods to filter specification requirements. The component or system designer and user that must rely upon a filter for protection is often left with little or no direction to help understand a filters characteristics. Worse yet, many of the more common techniques for testing (and thus describing) filtration characteristics are misleading because they are totally unrelated to a filters application. A presentation of currently used filter test methods and newer, more applicable tests are discussed.

This paper reports on a study that investigated the effect of composite contaminants on the wear of ball type valves. The objective was to develop a contamination control theory for predicting valve contaminant service life based on various mixture ratios of a silica test contaminant and a ferrous test contaminant. Filter specifications were determined which ensure valve contaminant service life. Theoretical considerations drew on contamination control theory and new relationships are introduced which account for ball valve wear due to two contaminants. Experimental tests were conducted with the Zeta test machine to establish particle abrasivity ratings and with the valve contaminant test stand to determine valve pressure degradation to contamination. It was found that less abrasive particles result in less valve performance degradation. This result substantiated the theoretical expressions relating the valve wear composite contaminant sensitivity coefficients.

The analysis and description of field generated containment in fluid systems (hydraulic or lubricating oil, fuels, water, etc.) continues to be one of the best indicators of system “health.” The monitoring of the contaminant provides an effective health measure by accurate determination of the contributing factors to system degradation. These include solid particles, water, additive depletion, and a host of resultant synergistic effects such as sludges, gels, etc. Their are many options available for field fluid analysis. Five specific analyses have been found to provide an extensive description of field contaminants. They are particle counting, gravimetric level analysis, proton induced X-ray emission (PIXE) analysis, ferrographic wear debris analysis, and water content analysis. Thorough descriptions of this procedures is provided with detailed application considerations.

This paper details an extensive study that was performed to define, quantify, and describe the contaminant found in automotive type transmissions. The results from the study were used to manufacture a new commercially available test contaminant that simulates the contaminant found in high mileage transmissions. The study was undertaken because no commercially available contaminant existed to test transmission related components, especially valves, pumps and filters. Most accepted test contaminants such as AC Fine or Course Test Dust were known not to give representative contaminant related results. The study consisted of collecting 29 oil samples from various mileage vehicles. The particle size distribution, gravimetric level, and chemical composition were found from the samples.

Electrohydraulic valves have seen increasing use in all fluid power applications, especially in the automotive field. This includes automobiles, heavy equipment, and all mobile equipment. Pulse width modulation (PWM) has been, and continues to be a popular choice for control in many applications. Common uses for such valves are in transmissions, anti-lock brake systems, electronic fuel injection systems, and active suspension systems. These broad application areas usually all have one common application limitation, use of a low force electromechanical valve actuator. This is most commonly an electric solenoid and often imparts less than one pound of force to actuate the valve. This use of low force valve actuators has thus magnified the effect that contaminants have on the valves. Compounded with this is the varying nature of field induced and generated contaminants.

Three procedures for assessing the integrity of hydraulic hose/coupling connections were developed and shown to be effective methods for detecting hose failures induced by improper coupling connections. Each procedure's sole purpose is to detect one or two specific failure modes of hose assemblies. The development of these procedures arose from a need to quantitatively measure hose/coupling integrity. The three test procedures are the Mechanical/Hydrostatic Coupling/Hose Separation Test (FPRC-LH-S22), the Pneumatic Surge Test (FPRC-LH-S21), and the Progressive Leakage Test (FPRC-LH-S4). The results of each test yield not only failure modes, but a means for quantitative integrity rating. The Hose Assembly Rating is a test-dependent measure developed to scale all test results from 1 (poor) to 10 (excellent). This rating provides a means for expedient, direct comparison of test results. The use of these test procedures has proved invaluable.