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FUELS AND LUBES MAY 2018 • E&MJ; 39 www.e-mj.com do not realize that some of their critical operational factors can be significantly influenced by how lubricants are man- aged. For example, less than half realize that lubrication can influence unplanned downtime, and 64% are not clear about how extended oil drain intervals can gen- erate cost savings. Renée Power, Shell's global sector man- ager for mining, said, "40% of the compa- nies we surveyed estimated that they had incurred costs of at least $250,000 over the last 3 years from breakdowns due to ineffective lubrication. This shows poten- tial for companies to achieve a significant boost to profits by working closely with a supplier like Shell Lubricants to improve equipment lubrication practices." However, with maintenance manag- ers facing budget and time constraints, and only 34% of businesses making use of regular visits from their lubricant sup- plier's technical staff, most are not well- equipped to take action. The study re- vealed that only 41% of companies have all the recommended procedures in place to manage lubricants effectively, and 59% recognize they don't conduct staff training on lubricants as regularly as they should. Misconceptions about lubricants are also evident, with 44% believing that all lubricants and greases provide the same level of performance. Power commented, "The impact of lubrication on Total Cost of Ownership is too often underestimated. Almost half of companies surveyed wouldn't expect to see a reduction in maintenance costs resulting from lubrication, but we have helped deliver more than $44 million in savings to mining companies over the last five years." The Big 3 The Shell report looked at three prima- ry lubrication applications in the mining industry: engines, drivetrains and open gears, and many other sources confirm the necessity of "getting it right," particu- larly when it comes to lubrication choices for expensive diesel engines. The selec- tion process to choose the best oil for the application involves considerations based on engine design characteristics, opera- tional parameters and environment (tem- perature, humidity, site used at altitude or underground, etc.). Changes in fleet con- figuration can complicate the process. For example, recent announcements by Lieb- herr, Volvo Penta and other suppliers in- dicate that through replacement, repower or new fleet purchase, Tier 4 and Europe- an Union (EU) Stage V compliant diesels are becoming more prevalent in mining applications — and bringing with them new requirements and concerns about lu- brication. Liebherr just delivered the first Tier 4 diesel-powered R 9400 hydraulic excavator to a mine in the western U.S., and Volvo Penta said that Sandvik is now installing Volvo Penta's Stage V engines in its underground loaders and trucks, fol- lowing prototyping and extensive testing of a Sandvik LH517 LHD with a Stage V engine at a mine site in Finland. Industry acceptance of new-genera- tion engines is concomitant with expecta- tions of higher efficiency, much of which is gained through increased heat produc- tion, higher system pressures and tighter tolerances — all of which pose challenges for engine oils tasked with the job of pro- tecting internal parts. Commodities such as engine oil that typically come in a can or drum aren't usually regarded as com- plex creations, but premium oils actually are carefully formulated to meet a num- ber of challenges. Cummins, for example, pointed out the many tasks that engine oil is called upon to perform on a continual basis. These include: Lubrication – The oil forms a hydro- dynamic film between metal surfaces, preventing metal-to-metal contact and reducing friction. When the oil film is not sufficient to prevent metal-to-metal contact, bad things can happen — heat is generated through friction, local weld- ing occurs, and metal transfer results in scuffing or seizing. Extreme Pressure Wear Control – Modern lubricants contain extreme pressure an- ti-wear additives. These additives form a chemically bonded molecular film on the metal surfaces at high pressure to prevent direct contact and wear when the load on the parts is high enough to eliminate the hydrodynamic oil film. Cleaning – Oil acts as a cleaning agent in the engine by flushing contaminants from critical components. Sludge, varnish, and oxidation buildup on the pistons, rings, valve stems and seals will lead to severe engine damage, if not controlled by the oil. Oil formulated with the optimal ad- ditives will hold these contaminants in suspension until they are removed by the oil filtration system or during the course of an oil change. Protection – Oil provides a protective bar- rier, isolating non-like metals to prevent corrosion. Corrosion, like wear, results in the removal of metal from engine parts. Corrosion works like a slow-acting wear mechanism. Cooling – Engines need cooling of inter- nal components that the primary cooling system cannot provide. The lubricating oil provides an excellent heat transfer medi- um. Heat is transferred to the oil through contact with various components, which is then transferred to the primary cooling system at the oil cooler. Sealing – Oil acts as a combustion seal filling the uneven surfaces of the cylinder liner, piston, valve stem and other inter- nal engine components. Shock-Damping – The oil film between contacting surfaces provides cushioning and shock-damping. The damping effect is essential to highly loaded areas such as the bearings, pistons, connecting rods, and the gear train. Hydraulic Action – Oil acts as a working hydraulic media within the engine. Exam- A key to successful selection of an oil or grease for any given application is to ensure that the formulation is capable of maintaining a consistent protective layer between components during all aspects of operation.