Investigation Of Self-repairing Additive's Impact On Diesel Engine Lubricating Oil's Anti-wear Performance

Wear friction is the main reason why equipment failures occurred,and lubricants with additives are the mostly used measures for friction decreasing and wear reducing. With the development of wear self-repairing technologies,self-repairing materials have drawn more and more attention.Wear self-repairing additives can improve lubricant's anti-wear properties and repair the worn face effectively.Study on the self-repairing lubricating additives will greatly contribute economic and social benefits to the industrial fields,like cars,machinery and national defense.Therefore, it is very valuable and necessary to study the anti-wear properties of self-repairing additives in lubricating oil.A self-repairing cermet lubricating additive whose main content is Mg₆Si₄O₁₀(OH)₈ was selected as the main composition.This self-repairing additive has been applied for trials to automotive engine,railway locomotive,industrial machinery,etc.The result showed that these trials are successful.But there are few reports about its application on marine diesel engine.Therefore,according to the research requirements,in order to study the self-repairing additive's influence on lubricant's anti-wear and anti-friction performance,marine diesel engine lubricating oil added self-repairing additive was studied by changing the tribological system's element in this thesis.In addition,this additive was added in a dredger's diesel engine lubrication system for practical tests,then use oil analysis techniques to evaluate the lubricating oil samples in order to analyze the additive's actual anti-wear and anti-friction effects,and the mechanism was discussed at last.In this thesis,the self-repairing additive was added to diesel engine lubricant oil and a four-ball test was applied.The results showed that this additive had well adaptability in engine oil,and it can improve the engine oil's anti-wear and anti-friction performance effectively,but when it came to hydraulic oil and mechanic oil,the additive's performance was not obvious.In addition,the self-repairing additive was added to an operating dredger's diesel engine lubrication system,then sampled the lubricate oil periodically and applied oil analysis techniques to study the engines wear condition.The research suggested that self-repairing additive can smooth the wear of diesel engine's cylinder liner piston ring.The mechanism of self-repairing additives may be that the additive polished the rubbing surface,and played a role of "miniature ball bearing".Meanwhile,the additive particles reacted with wear particles and other materials during the friction progress,at last a anti-wear film was formed on the surface of friction pair.