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Tilting-pad Bearing
Fluid bearings are bearings in which the load is supported by a thin layer of rapidly moving pressurized liquid or gas between the bearing surfaces. Since there is no contact between the moving parts, there is no sliding friction, allowing fluid bearings to have lower friction, wear and vibration than many other types of bearings. Thus, it is possible for some fluid bearings to have near-zero wear if operated correctly. They can be broadly classified into two types: fluid dynamic bearings (also known as hydrodynamic bearings) and hydrostatic bearings. Hydrostatic bearings are externally pressurized fluid bearings, where the fluid is usually oil, water or air, and is pressurized by a pump. Hydrodynamic bearings rely on the high speed of the journal (the part of the shaft resting on the fluid) to pressurize the fluid in a wedge between the faces. Fluid bearings are frequently used in high load, high speed or high precision applications where ordinary ball bearings would have shor ... [...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] |
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] |
Collection Of Air Bearings From Specialty Components
Collection or Collections may refer to: Computing * Collection (abstract data type), the abstract concept of collections in computer science * Collection (linking), the act of linkage editing in computing * Garbage collection (computing), automatic memory management method Mathematics * Set (mathematics) * Class (set theory) * Family of sets * Indexed family * Multiset * Parametric family Albums Collection * ''Collection'' (Soccer Mommy album), 2017 * ''Collection'' (2NE1 album), 2012 * ''Collection'' (Agnes album), 2013 * ''Collection'' (Arvingarna album), 2002 * ''Collection'' (Jason Becker album), 2008 * ''Collection'' (Tracy Chapman album), 2001 * ''Collection'' (The Charlatans album) * ''Collection'' (Dave Grusin album), 1989 * ''Collection'' (The Jam album) * ''Collection'' (Wynonna Judd album) * ''Collection'' (Magnus Uggla album), 1985 * ''Collection'' (Men Without Hats album), 1996 * ''Collection'' (MFÖ album), 2003 * ''Collection'' (Mike Oldfield alb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stave Bearing
A stave bearing is a simple journal bearing where a shaft rotates in a bearing housing. Rather than the usual arrangement where the fixed part of the bearing surrounds most of the circumference of the shaft in one or two pieces, a stave bearing uses a large number of axial stave (wood), staves to support the shaft. A large housing is made with grooves running along the shaft, these grooves being filled with strips of suitable material, originally wood. Uses Stave bearings have long been associated with ships and their propeller shafts. The bearing is suitable for slow speeds and high loads. When used on ships, the bearing is designed to run immersed in water, allowing its use outboard of the stern gland or stuffing box. Stave bearings are also well suited to applications such as rudder shafts, where rotation is intermittent and reciprocating, rather than continuous and unidirectional. Other bearing types, such as some ball bearings, don't perform well under this type of use and may ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Bearing
Plain bearing on a 1906 S-Motor locomotive showing the axle, bearing, oil supply and oiling pad A sliding table with four cylindrical bearings A 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, comprising just a bearing surface and no rolling elements. Therefore, the part of the 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 ways on the bed of a lathe. Plain bearings, in general, are the least expensive type of bearing. They are also compact and lightweight, and they have a high load-carrying capacity. Design The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garrett AiResearch
Garrett AiResearch was a manufacturer of turboprop engines and turbochargers, and a pioneer in numerous aerospace technologies. It was previously known as Aircraft Tool and Supply Company, Garrett Supply Company, AiResearch Manufacturing Company, or simply AiResearch. In 1964, Garrett AiResearch merged with Signal Oil & Gas, to form a company renamed in 1968 to Signal Companies. In 1985, it merged with Allied Corporation, forming AlliedSignal. In 1999 AlliedSignal acquired Honeywell and adopted the Honeywell name. Founding years John Clifford "Cliff" Garrett founded a company in Los Angeles in 1936 which came to be known as Garrett AiResearch or simply AiResearch. The company was first named Aircraft Tool and Supply Company. In early 1937, it was renamed as Garrett Supply Company. In 1939, it became AiResearch and shortly thereafter AiResearch Manufacturing Company, which then became a division within the Garrett Corporation. Already operating his Garrett Supply and Airsuppl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Foil Bearing
A foil bearing, also known as a foil-air bearing, is a type of air bearing. A shaft is supported by a compliant, spring-loaded foil journal lining. Once the shaft is spinning fast enough, the working fluid (usually air) pushes the foil away from the shaft so that no contact occurs. The shaft and foil are separated by the air's high pressure, which is generated by the rotation that pulls gas into the bearing via viscosity effects. The high speed of the shaft with respect to the foil is required to initiate the air gap, and once this has been achieved, no wear occurs. Unlike aerostatic or hydrostatic bearings, foil bearings require no external pressurisation system for the working fluid, so the hydrodynamic bearing is self-starting. Development Foil bearings were first developed in the late 1950s by AiResearch Mfg. Co. of the Garrett Corporation using independent R&D funds to serve military and space applications. They were first tested for commercial use in United Airlines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Precession
Precession is a change in the orientation of the rotational axis of a rotating body. In an appropriate reference frame it can be defined as a change in the first Euler angle, whereas the third Euler angle defines the rotation itself. In other words, if the axis of rotation of a body is itself rotating about a second axis, that body is said to be precessing about the second axis. A motion in which the second Euler angle changes is called '' nutation''. In physics, there are two types of precession: torque-free and torque-induced. In astronomy, ''precession'' refers to any of several slow changes in an astronomical body's rotational or orbital parameters. An important example is the steady change in the orientation of the axis of rotation of the Earth, known as the precession of the equinoxes. Torque-free or torque neglected Torque-free precession implies that no external moment (torque) is applied to the body. In torque-free precession, the angular momentum is a constant, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decibel
The decibel (symbol: dB) is a relative unit of measurement equal to one tenth of a bel (B). It expresses the ratio of two values of a Power, root-power, and field quantities, power or root-power quantity on a logarithmic scale. Two signals whose level (logarithmic quantity), levels differ by one decibel have a power ratio of 101/10 (approximately ) or root-power ratio of 101/20 (approximately ). The strict original usage above only expresses a relative change. However, the word decibel has since also been used for expressing an Absolute scale, absolute value that is relative to some fixed reference value, in which case the dB symbol is often suffixed with letter codes that indicate the reference value. For example, for the reference value of 1 volt, a common suffix is "#Voltage, V" (e.g., "20 dBV"). As it originated from a need to express power ratios, two principal types of scaling of the decibel are used to provide consistency depending on whether the scaling refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centripetal Force
Centripetal force (from Latin ''centrum'', "center" and ''petere'', "to seek") is the force that makes a body follow a curved trajectory, path. The direction of the centripetal force is always orthogonality, orthogonal to the motion of the body and towards the fixed point of the instantaneous osculating circle, center of curvature of the path. Isaac Newton coined the term, describing it as "a force by which bodies are drawn or impelled, or in any way tend, towards a point as to a centre". In Newtonian mechanics, gravity provides the centripetal force causing astronomical orbits. One common example involving centripetal force is the case in which a body moves with uniform speed along a circular path. The centripetal force is directed at right angles to the motion and also along the radius towards the centre of the circular path. The mathematical description was derived in 1659 by the Dutch physicist Christiaan Huygens. Formula From the kinematics of curved motion it is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bearing Surface
A bearing surface in mechanical engineering is the area of contact between two objects. It usually is used in reference to bolted joints and bearing (mechanical), bearings, but can be applied to a wide variety of engineering applications. The choice of bearing surface depends on the application, load, speed, and operating conditions, and the design must be able to withstand high loads, resist wear and corrosion, and operate at high speeds. On a screw, the bearing area loosely refers to the underside of the head. Strictly speaking, the bearing area refers to the area of the screw head that directly bears on the part being fastened. For a cylindrical bearing, it is the projected area perpendicular to the applied force. On a spring (device), spring, the bearing area refers to the amount of area on the top or bottom surface of the spring in contact with the constraining part.. The ways of machine tools, such as dovetail slides, box ways, prismatic ways, and other types of machine s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
