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Summary. Careful selection of the right lubricant(s) is required to keep a machine running smoothly. Lubrication Fundamentals, Third Edition, Revised and. monthly Lubrication Fundamentals column. Since Bob is the modest type, please allow me a moment to tell you a little more about the man behind the keyboard.
New Password. The extent of wear in equipment depends upon the degree of the metal-to-metal contact, either due to the equipment design or the nature of the operation.
For example, the equipment that is designed to experience minimal metal-to-metal contact, as is the case in most parts of an internal combustion engine, there is little friction and wear. However; the parts that are designed to have intimate metal-to-metal contact, such as gears and bearings, wear due to friction is extensive.
With respect to the effect of equipment operation on wear, high-speed, low-load operation leads to lower wear than slow-speed, high-load operation. This is because in the former case there is minimal metal-to-metal contact. A lubricant can be a solid, liquid, or gas, and lubrication is its primary function. The usual objective of the lubrication is to lubricate surfaces to minimize direct metal-to-metal contact and, hence, reduce friction and wear.
The term lubricant is also loosely applied to many other fluids that do not specifically perform this function. Examples include power and heat transmission fluids, hydraulic fluids, dielectric fluids, process oils, and the others. A lubricant performs many diverse functions, which help protect and prolong the life of the equipment .
These include the following: 1. Lubrication reduce friction and wear —Lubricant helps reduce friction and wear by introducing a lubricating film between mechanical moving parts, such as gears and bearings. Essentially the presence of a lubricating film minimizes the metal-to-metal contact and reduces the force necessary to move one surface against the other, thereby reducing wear and saving energy.
Cooling heat transfer —Lubricant acts as a heat sink and dissipates the heat away from the critical moving parts of the equipment, thereby decreasing the possibility of the machine component deformation and wear. The heat is either frictional heat that results from the metal surfaces rubbing against one another, such as in gears, or is conducted and radiated heat, which is due to the close proximity of the parts to a combustion source, such as the combustion chamber in an automobile engine.
Cleaning and Suspending —Lubricant facilitates smooth operation of the equipment by removing and suspending potentially harmful products, such as carbon, sludge, and varnish, and the other materials, such as dirt and wear debris. This lubricant function is important in operations that involve high operating temperatures, as in the case of an internal combustion engine or a transmission.