Engine lubricants

Dibasic acid esters and polyol esters are used as the bases in all aircraft jet-engine lubricants. They also are employed in aircraft greases that are subjected to wide temperature ranges. 

The Federal Trade Commission has aimounced a rule, effective November 30, 1995, that sets test procedures and labeling standards for recycled oil used as engine lubricating oil (35). The test procedures used are those contained in the Engine Oil Licensing and Certification System of the American Petroleum Institute (API) (36). The rule states in effect that if recycled oils meet the requirements of the API Certification System, such oils ate substantially equivalent to new oil for use as engine oil. This federal rule preempts certain state recycled oil rules (35). 

Engine cooling water High outlet temperature Engine lubricating oil system Low inlet pressure Fuel system ... 

These problems of engine lubrication can be overcome by using highly refined oil. The resistance to oxidation is further enhanced by the use of anti-oxidants. The addition of corrosion-inhibitors counters acidic materials produced by combustion at low engine temperatures. 

A recent application of this type of fluid is assistance in the removal of ingested salt spray from jet aircraft compressors and the neutralisation of corrosive effects. Other types of water-displacing fluids are claimed to have fingerprint neutralising properties or to be suitable for use on electrical equipment. Some oil-type materials serve temporarily as engine lubricants and contain suitable inhibitors to combat the corrosive products of combustion encountered in gasoline engines. 

Thus, the way to optimize the frequency of DPF regeneration is to examine the dilution of fuel in engine lubricant, while keeping under control the DPF reliability criteria. 

In conclusion, the DPF management is relatively complex and needs a good management of the compromise that is to secure the after-treatment system performance and the engine reliability Regenerate sufficiently to protect the DPF system and not too often to limit the engine lubricant dilution. 

The main cause of DPF ageing (and thus of its functional characteristics) is the accumulation of lubricant residues, which is directly proportional to the engine lubricant consumption and to the lubricant composition (ashes rate). 

The agents in this class are bicyclophosphates and bicyclothiophosphates. This class of agents is not specifically listed in the Chemical Weapons Convention nor is it covered by the language of the general definitions in the Schedules. Some of these chemicals have been used as fire retardants, oil lubricants, and for medicinal research. They also occur as breakdown products in some synthetic turbine engine lubricants and some rigid polyurethane foams. 

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