Engine lubrication


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Engine lubrication

In an internal combustion engine, the system for providing a continuous supply of oil between moving surfaces during engine operation. This viscous film, known as the lubricant, lubricates and cools the power transmission components while removing impurities, neutralizing chemically active products of combustion, transmitting forces, and damping vibrations. See Internal combustion engine, Lubricant

Automotive engines are generally lubricated with petroleum-base oils that contain chemical additives to improve their natural properties. Synthetic oils are used in gas turbines and may be used in other engines. Probably the most important property of oil is the absolute viscosity, which is a measure of the force required to move one layer of the oil film over the other. If the viscosity is too low, a protecting oil film is not formed between the parts. With high viscosity too much power is required to shear the oil film, and the flow of oil through the engine is retarded. Viscosity tends to decrease as temperature increases. Viscosity index (VI) is a number that indicates the resistance of an oil to changes in viscosity with temperature. The smaller the change in viscosity with temperature, the higher the viscosity index of the oil.

Small two-stroke cycle engines may require a premix of the lubricating oil with the fuel going into the engine, or the oil may be injected into the ingoing air-fuel mixture. This is known as a total-loss lubricating system because the oil is consumed during engine operation.

Most automotive engines have a pressurized or force-feed lubricating system in combination with splash and oil mist lubrication. The lubricating system supplies clean oil cooled to the proper viscosity to the critical points in the engine, where the motion of the parts produces hydrodynamic oil films to separate and support the various rubbing surfaces. The oil is pumped under pressure to the bearing points, while sliding parts are lubricated by splash and oil mist. After flowing through the engine, the oil collects in the oil pan or sump, which cools the oil and acts as a reservoir while the foam settles out. Some engines have an oil cooler to remove additional heat from the oil. See Wear

References in periodicals archive ?
The oil dripping from the cylinders, bearings and other parts, fall under gravity back into the sump, from where it is picked up by pump and recirculated through the engine lubrication system.
Hydraulic motors should be capable of giving high shaft power at low pressure under 1.0 bar, and engine lubrication oil temperature at 100[degrees]C (212[degrees]F).
Shell also used the briefing to call attention to its Rotella heavy-duty diesel engine lubrication limited warranty program, which was announced in mid-2011 and is free with the purchase and installation of Rotella T6 full synthetic, Rotella T5 synthetic blend or Rotella Triple Protection heavy duty engine oils.
"But we have run as high as 0.3 parts per million sulfur and [H.sub.2]S in our fuel, because we can't control it, and all that corrosive material really puts a strain on the engine lubrication system."
Thanks to a 45 degree maximum climbing ability and 35 degree lateral inclination, the oil pan on the Touareg was made deeper and the oil pump and oil intake have been designed to ensure sufficient oil is being pumped through the engine lubrication system, regardless of the inclination of the vehicle.
Coconut oil costs half as much as 2T oil, provides better engine lubrication and appears to increase mileage.
The car also has an improved engine lubrication system which has been pioneered to provide more torque across a broader range of revs per minute and is more advanced than Formula One cars.
Therefore, the quality of the oil's base stock has a much larger role in two-cycle gas engine lubrication than it does in other types of motor oil.
The best way to design a preventive maintenance program for hydraulic systems is to integrate hydraulic maintenance procedures into an existing program for engine lubrication and inspection.
Garden Grove, CA, September 22, 2016 --(PR.com)-- Saint-Gobain Seals will be introducing a new polymer material solution specifically for critical applications in jet engine lubrication systems called Fluoroloy[R] A90 at the SAE E34 Symposium: "Future Developments in Aerospace Technology," to be held on September 28 in San Francisco, California.
The growing role of analysis in the design and development of the internal combustion engine lubrication system, over the last couple of decades, has been facilitated by continuous capability improvements of system-level and component-level models driven by advances in numerical techniques [1,2,1] as well as modeling of cavitation and aeration [4].

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