Remaining useful life RULER

The remaining useful life evaluation routine (RULER) is a useful monitoring program for used engine oils. The RULER system is based on a voltammetric method (Jefferies and Ameye, 1997 Kauffman, 1989 and 1994). The data allows the user to monitor the depletation of two additives ZDDP and the phenol/amineH+ antioxidant. The RULER results were compared to other standard analytical techniques, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), total base number (TBN), total acid number (TAN), and viscosity to determine any correlation between the techniques (Jefferies and Ameye, 1997 and 1998). The test concluded that the RULER instrument can... 

Antioxidant Condition by RULER , ASTM D6810 and D6971 The RULER0 is a portable instrument for determining the remaining useful life of machinery fluids based on their oxidative resistance levels. The instmment was developed to function with petroleum, synthetic hydrocarbon, ester-based and biodegradable lubricants. 

A second method, the RULER (remaining useful life evaluation routine) method [3], was used as a cross-check of TAN and TBN of samples as received. The method agreed to 1 mg KOH/g of oil with values obtained by an outside laboratory. 

Analysis by the RULER technique (Remaining Useful Life Evaluation Routine) studies the overall anti-oxidant additive reserve in fresh and used lubricant samples. It is particularly appropriate for the small sample masses available. The RULER voltammogram scan of a 15 minute ring zone sample for lubricant B shows substantial loss of anti-oxidant additive, as evidenced by the relative decline in the peak intensities in the lower curve of Fig 5, relative to the fresh lubricant, the upper curve. 

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