IMPROVED DYNAMIC SEAL PERFORMANCE USING DIFFERENTIAL WEAR PROCESSES

DYNAMIC SEAL PERFORMANCE CAN BE IMPROVED BY FAVORABLY CONTROLLING THE FLUID PRESSURE BETWEEN THE TWO SLIDING SURFACES. FAVORABLE CONTROL OF FLUID PRESSURE IN THE MIXED FRICTION REGIME CAN LEAD TO REDUCED GROSS WEAR AND REDUCED FRICTION. IN TRADITIONAL DESIGN THE DETAIL OF THE MIXED FRICTION LUBRICATION IS LEFT TO THE INHERENT CHARACTERISTICSOF THE MATERIALS THEMSELVES. BY ALTERING MATERIAL PROPERTIES IN A PATTERN OVER THE SURFACE AREA TO SOME DEPTH,IT IS POSSIBLE TO PRODUCE SURFACES WHICH HAVE WEAR DEPTHS AND/OR SURFACE CHARACTERISTIC VARIATIONS WHICH CORRESPOND TOTHESE PATTERNS. THESE PATTERNS OF VARYING EFFECTIVE FILM THICKNESS CAN BE USED TO ENHANCE MIXED FRICTION LUBRICATION.SUCH DIFFERENTIAL WEAR MAY BE STABLE EVEN WITH SIGNIFICANT AMOUNTS OF GROSS WEAR, THUS ENSURING A CONTINUATION OF THE BENEFITS ON PRESSURE DISTRIBUTION, GROSS WEAR, AND FRICTION.