Did you know that a lubricant could fail to deliver fuel-efficient engine performance? When a lubricant degrades, it not only loses its original properties of lubricity and dispersancy but also forms reaction products that are insoluble and corrosive. Much has been known about the risks associated with overextended oil drains and the buildup of carbon insolubles from combustion blow-by. However, little has been said about the impact of fine abrasives in a lube-oil relating to fuel economy over the engine’s life. One can imagine numerous scenarios in which solid abrasives suspended in the lube-oil could diminish optimum energy performance. Below is a list of several scenarios:
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Antiwear Additive Depletion.
High soot load of crankcase lubricants can impair the performance of anti-wear additives. Soot and dust particles exhibit polar absorbencies, and as such, can tie-up the anti-wear additive and diminish its ability to control friction in boundary contacts (cam nose, ring/ liner, etc.).
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Combustion Efficiency Losses.
Sooner or later, wear from abrasive particles and deposits from carbon and oxide insolubles interfere with efficient combustion in an engine. Valve train wear can impact timing and valve movement. Wear of rings, pistons and liners influences volumetric compression efficiency and combustion blow-by resulting in power loss. Particle-induced wear is greatest when sizes are in the same range as the oil film thickness. Controlling particles in the 3 to 10 micron range is vital as it has the greatest impact on engine wear rates correlated directly to the dust concentration levels in the sump.
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Frictional Losses.
When hard clearance-size particles disrupt oil films, including boundary chemical films, increased friction and wear will occur. There is an extremely high level of sensitivity at the ring-to-cylinder zone of the engine to both oil- and air-borne contaminants. Abrasive wear of the ring/cylinder area of the engine translates directly to increased friction, blow-by, compression losses and finally leading to a reduced fuel economy.
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Stiction Losses.
Deposits in the combustion chamber and valve area can lead to restriction movements in rings and valve control. When hard particle contamination agglomerates with soot and sludge to form adherent deposits between valves and guides, a tenacious interference, called stiction, results. Stiction causes power loss. Valve mis-timings leading to incomplete combustion and burnt valve seat.
Particle induced wear greatest
when particle size in same range as oil film
thickness.
Reducing oil contamination by 98 percent, results in a nearly 5 percent reduction in fuel consumption & wear and friction are reduced by 93 percent and 2.9 percent respectively. Needless to say that ultimately may lead to a major breakdown of the machinery itself.
So we see that clean lube-oil is important to control wear, reduce fuel consumption and emissions, perhaps it’s also time to begin asking the laboratories to carry out a reporting of particle counts. Measuring is important !! Remember, what gets measured, gets done !!!!
Article compiled by Mr. Sanjeev Dubey , Technical Superintendent
First Aquatic Meet On Campus
It was a bout of testing the boundaries of both physical strength and stamina for the cadets at SIMS Lonavala during their first ever Aquatic Meet. The week-long event culminated with a Grand Finale on Friday, 22nd February 2008 where the best for each category competed with each other in the true spirit of sportsmanship. The event saw 47 cadets participating and contending for the glory of the win throughout the week and the following emerged winners for the categories contested:
At the end of the meet, the winners and runners-up were felicitated by the Director and Principal and bestowed with medals and certificates to honour their success. The management is pleased that their aim to inculcate active participation and thus building esprit de corps among the young cadets was largely met. Furthermore, this event being the first sporting competition of 2008 heralds the beginning of an active sporting future on campus.
Did you know that a lubricant could fail to deliver fuel-efficient engine performance?
