Figure 8 The diameter of steel ball wear scar while the 928 and 50-1-4Ф
aviation lubrication oil samples (oxidized for 2 hours) are applied
As expected, the total acid number (TAN, shown in Table 3) of the
oxidized 928 and 50-1-4Ф aviation lubrication oils were increasing with
higher oxidation temperature, which coincident with the anti-wear
testing shown in Figure 8. Both the TAN and diameter of wear scar would
be promoted rapidly while the oxidation temperature exceeds
230 oC. The oil quality of the oxidized oil samples is
undoubtedly deteriorated in the oxidation reactions. As described
before, the color number of the oxidized oil samples might provide a
readily method to identify the oil quality through the direct
measurement of the color-related-oxidation-products. As shown in Figure
2s, the methods still need improvement to elevate the resolution ratio
and measurement range. More sophisticated and effective testing
strategies about designment on more effective filtration and thinner oil
pipe might be required to realize the above demands.