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Full Indicator Movement
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 (the range), 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 indicator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dial Indicator
In various contexts of science, technology, and manufacturing (such as machining, metal fabrication, fabricating, and additive manufacturing), an indicator is any of various instruments used to accurately measure small distances and angles, and wikt:amplify, amplify them to make them more obvious. The name comes from the concept of ''wikt:indicate#Verb, indicating'' to the user that which their naked eye cannot discern; such as the presence, or exact quantity, of some small distance (for example, a small height difference between two flat surfaces, a slight lack of concentricity between two cylinders, or other small physical deviations). The classic mechanical version, called a dial indicator, provides a dial (measurement), dial display similar to a clock face with clock hands; the hands point to graduations in circular scales on the dial which represent the distance of the probe tip from a zero setting. The internal works of a mechanical dial indicator are similar to the precisio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineering Drawing
An engineering drawing is a type of technical drawing that is used to convey information about an object. A common use is to specify the geometry necessary for the construction of a component and is called a detail drawing. Usually, a number of drawings are necessary to completely specify even a simple component. These drawings are linked together by a "master drawing." This "master drawing" is more commonly known as an assembly drawing. The assembly drawing gives the ''drawing numbers'' of the subsequent detailed components, quantities required, construction materials and possibly 3D images that can be used to locate individual items. Although mostly consisting of pictographic representations, Engineering drawing abbreviations and symbols, abbreviations and symbols are used for brevity and additional textual explanations may also be provided to convey the necessary information. The process of producing engineering drawings is often referred to as technical drawing or drafting ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geometric Dimensioning And Tolerancing
Geometric dimensioning and tolerancing (GD&T) is a system for defining and communicating engineering tolerances via a Symbolic language (engineering), symbolic language on engineering drawings and computer-generated Solid modeling, 3D models that describes a physical object's nominal geometry and the permissible variation thereof. GD&T is used to define the nominal (theoretically perfect) geometry of parts and assemblies, the allowable variation in size, form, orientation, and location of individual features, and how features may vary in relation to one another such that a component is considered satisfactory for its intended use. Dimensional specifications define the nominal, as-modeled or as-intended geometry, while tolerance specifications define the allowable physical variation of individual features of a part or assembly. There are several standards available worldwide that describe the symbols and define the rules used in GD&T. One such standard is American Society of Mecha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Engineering Drawing
An engineering drawing is a type of technical drawing that is used to convey information about an object. A common use is to specify the geometry necessary for the construction of a component and is called a detail drawing. Usually, a number of drawings are necessary to completely specify even a simple component. These drawings are linked together by a "master drawing." This "master drawing" is more commonly known as an assembly drawing. The assembly drawing gives the ''drawing numbers'' of the subsequent detailed components, quantities required, construction materials and possibly 3D images that can be used to locate individual items. Although mostly consisting of pictographic representations, Engineering drawing abbreviations and symbols, abbreviations and symbols are used for brevity and additional textual explanations may also be provided to convey the necessary information. The process of producing engineering drawings is often referred to as technical drawing or drafting ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Indicator (distance Amplifying Instrument)
In various contexts of science, technology, and manufacturing (such as machining, fabricating, and additive manufacturing), an indicator is any of various instruments used to accurately measure small distances and angles, and amplify them to make them more obvious. The name comes from the concept of '' indicating'' to the user that which their naked eye cannot discern; such as the presence, or exact quantity, of some small distance (for example, a small height difference between two flat surfaces, a slight lack of concentricity between two cylinders, or other small physical deviations). The classic mechanical version, called a dial indicator, provides a dial display similar to a clock face with clock hands; the hands point to graduations in circular scales on the dial which represent the distance of the probe tip from a zero setting. The internal works of a mechanical dial indicator are similar to the precision clockworks of a mechanical wristwatch, employing a rack and pinio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root Mean Square
In mathematics, the root mean square (abbrev. RMS, or rms) of a set of values is the square root of the set's mean square. Given a set x_i, its RMS is denoted as either x_\mathrm or \mathrm_x. The RMS is also known as the quadratic mean (denoted M_2), a special case of the generalized mean. The RMS of a continuous function is denoted f_\mathrm and can be defined in terms of an integral of the square of the function. In estimation theory, the root-mean-square deviation of an estimator measures how far the estimator strays from the data. Definition The RMS value of a set of values (or a continuous-time waveform) is the square root of the arithmetic mean of the squares of the values, or the square of the function that defines the continuous waveform. In the case of a set of ''n'' values \, the RMS is : x_\text = \sqrt. The corresponding formula for a continuous function (or waveform) ''f''(''t'') defined over the interval T_1 \le t \le T_2 is : f_\text = \sqrt , and the R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Roughness
Surface roughness or simply roughness is the quality of a surface of not being smooth and it is hence linked to human ( haptic) perception of the surface texture. From a mathematical perspective it is related to the spatial variability structure of surfaces, and inherently it is a multiscale property. It has different interpretations and definitions depending on the disciplines considered. In surface metrology, surface roughness is a component of surface finish (surface texture). It is quantified by the deviations in the direction of the normal vector of a real surface from its ideal form. If these deviations are large, the surface is rough; if they are small, the surface is smooth. Roughness is typically assumed to be the high-frequency, short-wavelength component of a measured surface. However, in practice it is often necessary to know both the amplitude and frequency to ensure that a surface is fit for a purpose. Role and effect Roughness plays an important role in determin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lathe (metal)
In machining, a metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called ''lathes'', or else referred to by more-specific subtype names ('' toolroom lathe'', '' turret lathe'', etc.). These rigid machine tools remove material from a rotating workpiece via the (typically linear) movements of various cutting tools, such as tool bits and drill bits. Metal lathes can vary greatly, but the most common design is known as the universal lathe or parallel lathe. Construction The design of lathes can vary greatly depending on the intended application; however, basic features are common to most types. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concentric
In geometry, two or more objects are said to be ''concentric'' when they share the same center. Any pair of (possibly unalike) objects with well-defined centers can be concentric, including circles, spheres, regular polygons, regular polyhedra, parallelograms, cones, conic sections, and quadrics. Geometric objects are '' coaxial'' if they share the same axis (line of symmetry). Geometric objects with a well-defined axis include circles (any line through the center), spheres, cylinders, conic sections, and surfaces of revolution. Concentric objects are often part of the broad category of '' whorled patterns'', which also includes '' spirals'' (a curve which emanates from a point, moving farther away as it revolves around the point). Geometric properties In the Euclidean plane, two circles that are concentric necessarily have different radii from each other.. However, circles in three-dimensional space may be concentric, and have the same radius as each other, but nevert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roundness (object)
Roundness is the measure of how closely the shape of an object approaches that of a mathematically perfect circle. Roundness applies in Plane (mathematics), two dimensions, such as the cross section (geometry), cross sectional circles along a cylinder, cylindrical object such as a shaft (mechanical engineering), shaft or a rolling-element bearing#Cylindrical roller, cylindrical roller for a bearing. In geometric dimensioning and tolerancing, control of a cylinder can also include its fidelity to the longitudinal axis, yielding cylindricity. The analogue of roundness in three-dimensional space, three dimensions (that is, for spheres) is ''sphericity''. Roundness is dominated by the shape's gross features rather than the definition of its edges and corners, or the surface roughness of a manufactured object. A smooth ellipse can have low roundness, if its eccentricity (mathematics), eccentricity is large. Regular polygons increase their roundness with increasing numbers of sides, ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotation Around A Fixed Axis
Rotation around a fixed axis or axial rotation is a special case of rotational motion around an ''axis of rotation'' fixed, stationary, or static in three-dimensional space. This type of motion excludes the possibility of the instantaneous axis of rotation changing its orientation (geometry), orientation and cannot describe such phenomena as nutation, wobbling or precession. According to Euler's rotation theorem, simultaneous rotation along a number of stationary axes at the same time is impossible; if two rotations are forced at the same time, a new axis of rotation will result. This concept assumes that the rotation is also stable, such that no torque is required to keep it going. The kinematics and dynamics (mechanics), dynamics of rotation around a fixed axis of a rigid body are mathematically much simpler than those for Rigid body dynamics#Rigid-body angular momentum, free rotation of a rigid body; they are entirely analogous to those of linear motion along a single fixed di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
