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Machining Vibrations
Machining vibrations, also called chatter, are the relative movement between the workpiece and the cutting tool. The vibrations result in waves on the machined surface. This affects typical machining processes, such as turning, milling and drilling, and atypical machining processes, such as grinding. A chatter mark is an irregular surface flaw left by a wheel that is out of true in grinding or regular mark left when turning a long piece on a lathe, due to machining vibrations. As early as 1907, Frederick W. Taylor described machining vibrations as the most obscure and delicate of all the problems facing the machinist, an observation still true today, as shown in many publications on machining. The explanation of the machine tool regenerative chatter was made by Tobias. S. A. and W. Fishwick in 1958, by modeling the feedback loop between the metal cutting process and the machine tool structure, and came with the stability lobes diagram. The structure stiffness, damping ratio an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Relative Movement
Kinematics is a subfield of physics, developed in classical mechanics, that describes the motion of points, bodies (objects), and systems of bodies (groups of objects) without considering the forces that cause them to move. Kinematics, as a field of study, is often referred to as the "geometry of motion" and is occasionally seen as a branch of mathematics. A kinematics problem begins by describing the geometry of the system and declaring the initial conditions of any known values of position, velocity and/or acceleration of points within the system. Then, using arguments from geometry, the position, velocity and acceleration of any unknown parts of the system can be determined. The study of how forces act on bodies falls within kinetics, not kinematics. For further details, see analytical dynamics. Kinematics is used in astrophysics to describe the motion of celestial bodies and collections of such bodies. In mechanical engineering, robotics, and biomechanics kinematics is used t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Time Domain
Time domain refers to the analysis of mathematical functions, physical signals or time series of economic or environmental data, with respect to time. In the time domain, the signal or function's value is known for all real numbers, for the case of continuous time, or at various separate instants in the case of discrete time. An oscilloscope is a tool commonly used to visualize real-world signals in the time domain. A time-domain graph shows how a signal changes with time, whereas a frequency-domain graph shows how much of the signal lies within each given frequency band over a range of frequencies. Though most precisely referring to time in physics, the term ''time domain'' may occasionally informally refer to position in space when dealing with spatial frequencies, as a substitute for the more precise term ''spatial domain''. Origin of term The use of the contrasting terms ''time domain'' and ''frequency domain'' developed in U.S. communication engineering in the late 194 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Balancing Machine
A balancing machine is a measuring tool used for balancing rotating machine parts such as rotors for electric motors, Fan (mechanical), fans, turbines, disc brakes, disk storage, disc drives, propellers and pumps. The machine usually consists of two rigid pedestals, with suspension and Bearing (mechanical), bearings on top supporting a mounting platform. The unit under test is bolted to the platform and is rotated either with a belt-, air-, or end-drive. As the part is rotated, the vibration in the suspension is detected with sensors and that information is used to determine the amount of unbalance in the part. Along with phase information, the machine can determine how much and where to add or remove weights to balance the part. Hard-bearing vs. soft-bearing There are two main types of balancing machines, hard-bearing and soft-bearing. The difference between them, however, is in the suspension and not the bearings. In a hard-bearing machine, balancing is done at a frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Total Indicator Reading
In metrology and the fields that it serves (such as manufacturing, machining, and engineering), total indicator reading (TIR), also known by the newer name full indicator movement (FIM), is the difference between the maximum and minimum measurements, that is, readings of an indicator, on the planar, cylindrical, or contoured surface of a part,{{cite web , url=http://www.engineersedge.com/engineering/Engineering_Terms_Glossary/T/total_indicator_reading_tir_4448.htm , title=Total indicator reading (TIR) , accessdate=2011-03-31 , url-status=dead , archiveurl=https://archive.today/20120729021818/http://www.engineersedge.com/engineering/Engineering_Terms_Glossary/T/total_indicator_reading_tir_4448.htm , archivedate=2012-07-29 showing its amount of deviation from flatness, roundness (circularity), cylindricity, concentricity with other cylindrical features, or similar conditions. The indicator traditionally would be a dial indicator; today dial-type and digital indicators coexist. The ear ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
COMPUTER AIDED MANUFACTURING
Computer-aided manufacturing (CAM) also known as computer-aided modeling or computer-aided machining is the use of software to control machine tools in the manufacturing of work pieces. This is not the only definition for CAM, but it is the most common; CAM may also refer to the use of a computer to assist in all operations of a manufacturing plant, including planning, management, transportation and storage. Its primary purpose is to create a faster production process and components and tooling with more precise dimensions and material consistency, which in some cases, uses only the required amount of raw material (thus minimizing waste), while simultaneously reducing energy consumption. CAM is now a system used in schools and lower educational purposes. CAM is a subsequent computer-aided process after computer-aided design (CAD) and sometimes computer-aided engineering (CAE), as the model generated in CAD and verified in CAE can be input into CAM software, which then controls the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trial And Error
Trial and error is a fundamental method of problem-solving characterized by repeated, varied attempts which are continued until success, or until the practicer stops trying. According to W.H. Thorpe, the term was devised by C. Lloyd Morgan (1852–1936) after trying out similar phrases "trial and failure" and "trial and practice". Under Morgan's Canon, animal behaviour should be explained in the simplest possible way. Where behavior seems to imply higher mental processes, it might be explained by trial-and-error learning. An example is a skillful way in which his terrier Tony opened the garden gate, easily misunderstood as an insightful act by someone seeing the final behavior. Lloyd Morgan, however, had watched and recorded the series of approximations by which the dog had gradually learned the response, and could demonstrate that no insight was required to explain it. Edward Lee Thorndike was the initiator of the theory of trial and error learning based on the findings he sh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Knowhow
Know-how (or knowhow, or procedural knowledge) is a term for practical knowledge on how to accomplish something, as opposed to "know-what" (facts), "know-why" (science), or "know-who" (communication). It is also often referred to as street smarts (sometimes conceived as the opposite of book smarts), and a person employing their street smarts as ''street wise''. Know-how is often tacit knowledge, which means that it can be difficult to transfer to another person by means of writing it down or verbalising it. The opposite of tacit knowledge is explicit knowledge. Industrial know-how In the context of industrial property (now generally viewed as intellectual property or IP), know-how is a component in the transfer of technology in national and international environments, co-existing with or separate from other IP rights such as patents, trademarks and copyright and is an economic asset. When it is transferred by itself, know-how should be converted into a trade secret before transf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robustify
Robustification is a form of optimisation whereby a system is made less sensitive to the effects of random variability, or noise, that is present in that system's input variables and parameters. The process is typically associated with engineering systems, but the process can also be applied to a political policy, a business strategy or any other system that is subject to the effects of random variability. Clarification on definition Robustification as it is defined here is sometimes referred to as parameter design or robust parameter design (RPD) and is often associated with Taguchi methods. Within that context, robustification can include the process of finding the inputs that contribute most to the random variability in the output and controlling them, or tolerance design. At times the terms design for quality or Design for Six Sigma (DFFS) might also be used as synonyms Principles Robustification works by taking advantage of two different principles. Non-linearities Consid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Machinist
A machinist is a tradesperson or trained professional who not only operates machine tools, but also has the knowledge of tooling and materials required to create set ups on machine tools such as milling machines, grinders, lathes, and drilling machines. A competent machinist should have a well-developed mechanical aptitude, the ability to correctly use precision measuring instruments, and a working knowledge of the proper speeds and feeds required for successfully utilizing the various work and tool materials commonly used in most machining operations. Nature of work Mass-produced parts of machines are more common today, but still require machinists and millwrights to calibrate and install machine parts to manufacture other parts. In many parts of the economy, however, custom-made parts are required for various uses. A machinist may work on manufacturing something simple like a motorcycle frame part, a piece of an internal combustion motor, or something extraordinarily complex, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cutting Tool
In the context of machining, a cutting tool or cutter is typically a hardened metal tool that is used to cut, shape, and remove material from a workpiece by means of machining tools as well as abrasive tools by way of shear deformation. The majority of these tools are designed exclusively for metals. There are several different types of single edge cutting tools that are made from a variety of hardened metal alloys that are ground to a specific shape in order to perform a specific part of the turning process resulting in a finished machined part. Single edge cutting tools are used mainly in the turning operations performed by a lathe in which they vary in size as well as alloy composition depending on the size and the type of material being turned. These cutting tools are held stationary by what is known as a tool post which is what manipulates the tools to cut the material into the desired shape. Single edge cutting tools are also the means of cutting material performed by metal s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frederick Winslow Taylor
Frederick Winslow Taylor (March 20, 1856 – March 21, 1915) was an American mechanical engineer. He was widely known for his methods to improve industrial efficiency. He was one of the first management consultants. In 1909, Taylor summed up his efficiency techniques in his book ''The Principles of Scientific Management'' which, in 2001, Fellows of the Academy of Management voted the most influential management book of the twentieth century. His pioneering work in applying engineering principles to the work done on the factory floor was instrumental in the creation and development of the branch of engineering that is now known as industrial engineering. Taylor made his name, and was most proud of his work, in scientific management; however, he made his fortune patenting steel-process improvements. As a result, scientific management is sometimes referred to as ''Taylorism''. Biography Taylor was born in 1856 to a Quaker family in Germantown, Philadelphia, Pennsylvania. Taylor's f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grinding (abrasive Cutting)
Grinding is a type of abrasive machining process which uses a grinding wheel as Cutting tool (machining), cutting tool. A wide variety of machines are used for grinding, best classified as portable or stationary: * Portable power tools such as angle grinders, die grinders and abrasive saw, cut-off saws * Stationary power tools such as bench grinders and abrasive saw, cut-off saws * Stationary hydropower, hydro- or human power, hand-powered grindstone (tool), sharpening stones Milling practice is a large and diverse area of manufacturing and Tool and die maker, toolmaking. It can produce very fine finishes and very accurate dimensions; yet in mass production contexts, it can also rough out large volumes of metal quite rapidly. It is usually better suited to the machining of very Hardness, hard materials than is "regular" machining (that is, cutting larger chips with cutting tools such as tool bits or milling cutters), and until recent decades it was the only practical way to mach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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