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Lubrication
Lubrication is the process or technique of using a lubricant to reduce friction and wear and tear in a contact between two surfaces. The study of lubrication is a discipline in the field of tribology. Lubrication mechanisms such as fluid-lubricated systems are designed so that the applied load is partially or completely carried by hydrodynamic or hydrostatic pressure, which reduces solid body interactions (and consequently friction and wear). Depending on the degree of surface separation, different lubrication regimes can be distinguished. Adequate lubrication allows smooth, continuous operation of machine elements, reduces the rate of wear, and prevents excessive stresses or seizures at bearings. By repelling water and other substances, it also reduces corrosion. When lubrication breaks down, components can rub destructively against each other, causing heat, local welding, destructive damage and failure. Lubrication mechanisms Fluid-lubricated systems As the load incre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Lubrication System
Automatic lubrication systems (ALS), also known as centralized lubrication systems (CLS), are mechanical devices used in industrial machines and engines to apply specified quantities of a lubricant to distribution points while the machine is operating. Introduction An automatic lubrication system consists of a reservoir with a pump, feed lines, valves, metering valves, and Injector, injectors. The automatic lubrication system is connected to a control system via Switch, switches. The control system may involve human input or may be computerised (Numerical control, computer numerical control or CNC). There are advantages of using an automatic lubrication system over a manual system. For example, there are savings in the costs of human resources. The dangers of accessing difficult to reach lubrication points while a machine is running are avoided. Machines can be running when lubrication takes place, thus decreasing disruption to production. Manual lubrication may result in o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Splash Lubrication
Splash lubrication is a rudimentary form of lubrication found in early engines and transmissions. Such engines could be external combustion engines (such as stationary steam engines), or internal combustion engines (such as petrol, diesel or paraffin engines). Description An engine that uses splash lubrication requires neither oil pump nor oil filter. Splash lubrication is an antique system whereby scoops on the big end, big-ends of the connecting rods dip into the oil sump and splash the lubricant upwards towards the cylinders, creating an oil mist which settles into droplets. The oil droplets then pass through drillings to the bearings and thereby lubricate the moving parts. Provided that the bearing is a ball bearing or a roller bearing, splash lubrication would usually be sufficient; however, plain bearings typically need a pressure feed to maintain the oil film, loss of which leads to overheating and seizure. In a transmission, some of the gears are partially submerged in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plain Bearing
file:NYC 100-driving-axle-friction-bearing.jpg, Plain bearing on a 1906 S-Motor locomotive showing the axle, bearing, oil supply and oiling pad file:Linear-table with detail numbered.png, A sliding table with four cylindrical bearings file:GWR Spoked wagon wheels.jpg, A Wheelset (rail transport), wheelset from a Great Western Railway (GWR) wagon showing a plain, or journal, bearing end A plain bearing, or more commonly sliding contact bearing and slide bearing (in railroading sometimes called a solid bearing, journal bearing, or friction bearing), is the simplest type of bearing (mechanical), bearing, comprising just a bearing surface and no rolling elements. Therefore, wikt:journal#Noun, the part of the Axle, shaft in contact with the bearing slides over the bearing surface. The simplest example of a plain bearing is a shaft rotating in a hole. A simple linear bearing can be a pair of flat surfaces designed to allow motion; e.g., a drawer and the slides it rests on or the way (mac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bearing (mechanical)
A ball bearing A bearing is a machine element that constrains relative motion to only the desired motion and reduces friction between moving parts. The design of the bearing may, for example, provide for free linear movement of the moving part or for free rotation around a fixed axis; or, it may prevent a motion by controlling the vectors of normal forces that bear on the moving parts. Most bearings facilitate the desired motion by minimizing friction. Bearings are classified broadly according to the type of operation, the motions allowed, or the directions of the loads (forces) applied to the parts. The term "bearing" is derived from the verb " to bear"; a bearing being a machine element that allows one part to bear (i.e., to support) another. The simplest bearings are bearing surfaces, cut or formed into a part, with varying degrees of control over the form, size, roughness, and location of the surface. Other bearings are separate devices installed into a machine or mach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lubricant
A lubricant (sometimes shortened to lube) is a substance that helps to reduce friction between surfaces in mutual contact, which ultimately reduces the heat generated when the surfaces move. It may also have the function of transmitting forces, transporting foreign particles, or heating or cooling the surfaces. The property of reducing friction is known as lubricity. In addition to industrial applications, lubricants are used for many other purposes. Other uses include cooking (oils and fats in use in frying pans and baking to prevent food sticking), to reduce rusting and friction in machinery, through the use of motor oil and Grease (lubricant), grease, bioapplications on humans (e.g., lubricants for Replacement joint, artificial joints), ultrasound examination, medical examination, and sexual intercourse. It is mainly used to reduce friction and to contribute to a better, more efficient functioning of a mechanism. History Lubricants have been in some use for thousands of year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tribology
Tribology is the science and engineering of understanding friction, lubrication and wear phenomena for interacting surfaces in relative Motion (physics), motion. It is highly interdisciplinary, drawing on many academic fields, including physics, chemistry, materials science, mathematics, biology and engineering. The fundamental objects of study in tribology are tribosystems, which are physical systems of contacting surfaces. Subfields of tribology include biotribology, nanotribology and space tribology. It is also related to other areas such as the coupling of corrosion and tribology in tribocorrosion and the contact mechanics of how surfaces in contact deform. Approximately 20% of the total energy expenditure of the world is due to the impact of friction and wear in the transportation, manufacturing, power generation, and residential sectors. Etymology The word ''tribology'' derives from the Ancient Greek, Greek root τριβ- of the verb , ''wiktionary:tribo-, tribo'', "I rub" in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oil Pump (internal Combustion Engine)
The oil pump is an internal combustion engine part that circulates engine oil under pressure to the rotating bearings, the sliding pistons and the camshaft of the engine. This lubricates the bearings, allows the use of higher-capacity fluid bearings, and also assists in cooling the engine. As well as its primary purpose for lubrication, pressurized oil is increasingly used as a hydraulic fluid to power small actuators. One of the first notable uses in this way was for hydraulic tappets in camshaft and valve actuation. Increasingly common recent uses may include the tensioner for a timing belt or variators for variable valve timing systems. Pumps The type of pump used varies. Gear pumps trochoid pumps and vane pumps are all commonly used. Plunger pumps have been used in the past, but these are now only used rarely, for small engines. To avoid the need for priming, the pump is always mounted low-down, either submerged or around the level of the oil in the sump. A short pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reynolds Equation
In fluid mechanics (specifically lubrication theory), the Reynolds equation is a partial differential equation governing the pressure distribution of thin viscous fluid films. It was first derived by Osborne Reynolds in 1886. The classical Reynolds Equation can be used to describe the pressure distribution in nearly any type of fluid film bearing; a bearing type in which the bounding bodies are fully separated by a thin layer of liquid or gas. General usage The general Reynolds equation is: \frac\left(\frac\frac\right)+\frac\left(\frac \frac\right) = \frac \left(\frac\right)+\frac \left(\frac\right)+\rho\left(w_a-w_b\right) - \rho u_a\frac - \rho v_a \frac + h\frac Where: *p is fluid film pressure. *x and y are the bearing width and length coordinates. *z is fluid film thickness coordinate. *h is fluid film thickness. *\mu is fluid viscosity. *\rho is fluid density. *u, v, w are the bounding body velocities in x, y, z respectively. *a, b are subscripts denoting the top and bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. Types of friction include dry, fluid, lubricated, skin, and internal -- an incomplete list. The study of the processes involved is called tribology, and has a history of more than 2000 years. Friction can have dramatic consequences, as illustrated by the use of friction created by rubbing pieces of wood together to start a fire. Another important consequence of many types of friction can be wear, which may lead to performance degradation or damage to components. It is known that frictional energy losses account for about 20% of the total energy expenditure of the world. As briefly discussed later, there are many different contributors to the retarding force in friction, ranging from asperity deformation to the generation of charges and changes in local structure. When two bodies in contact move relative to each other, due to these variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sabb Motor
Sabb Motor is a Norwegian maker of small marine diesel engines, mostly single-cylinder or twin-cylinder units. The firm was established as Damsgaard Motorfabrikk by two brothers, Alf and Håkon Søyland in 1925. The firm started building engines to meet the demand of fishermen who wanted simple, robust and reliable power for their boats. (The word 'Sabb' means toughness and reliability). History The brothers' cottage industry began by creating a 3HP hot-bulb engine. This was followed by a larger 7HP version which tended to suffer broken crankshafts, but the firm was able to solve the problem and re-launch their engines under the name ''Ny-Sabb'' (New Sabb). By 1975, Sabb Motor was producing 3,200 engines a year between 8 and 30 bhp. Facing market competition, the firm concentrated on providing 30bhp engines for ship’s lifeboats, a decision which increased worldwide demand. The UK's distributor of Sabb engines is Sleeman & Hawken Ltd. More recently, Sabb have established a l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
