MEASURING INSTRUMENTS CATALOG No.E2016
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LMitutoyo operates a policy of continuous improvement that aims to provide the customer with the benet of the latest technological advances.Therefore the company reserves the right to change any or all aspects of any product specication without notice.L-44L009018027036000901802703600090180270360009018027036000901802703600090180270360009018027036000901802703600090180270360902700180902700180902700180902700180902700180902700180902700180902700180902700180ΔZq=17.61µmΔZq=12.35µmΔZq=22.14µmΔZq=16.60µmΔZq=20.72µmΔZq=22.04µmΔZq=18.76µmΔZq=14.50µm■ Evaluating the Measured Prole Roundness Roundness testers use the measurement data to generate reference circles whose dimensions dene the roundness value. There are four methods of generating these circles, as shown below, and each method has individual characteristics so the method that best matches the function of the workpiece should be chosen. Each method results in a different center position for the reference circles and therefore affects the axial location of the circular feature measured.■ Effect of Filter Settings on the Measured Prole Proles can be ltered in various ways to reduce or eliminate unwanted detail, with a cut-off value set in terms of undulations per revolution (upr). The effect of different upr settings is shown in the diagrams below, which illustrate how the measured roundness value decreases as lower upr settings progressively smooth out the line. 15 uprA 1 UPR condition indicates eccentricity of the workpiece relative to the rotational axis of the measuring instrument. The amplitude of undulation components depends on the leveling adjustment.■ Undulations Per Revolution (UPR) data in the roundness graphs Amplitude Amplitude Amplitude Amplitude Amplitude Amplitude Amplitude Amplitude AmplitudeMeasurement result graphsAngleAngleAngleAngleAngleAngleAngleAngleAngleA 15 (or more) UPR condition is usually caused by tool chatter, machine vibration, coolant delivery effects, material non-homogeneity, etc., and is generally more important to the function than to the t of a workpiece.A 5 to 15 UPR condition often indicates unbalance factors in the machining method or processes used to produce the workpiece.A 3 to 5 UPR condition may indicate: (1) Deformation due to over-tightening of the holding chuck on the measuring instrument; (2) Relaxation deformation due to stress release after unloading from the holding chuck on the machine tool that created its shape.A 2 UPR condition may indicate: (1) insufcient leveling adjustment on the measuring instrument; (2) circular runout due to incorrect mounting of the workpiece on the machine tool that created its shape; (3) the form of the workpiece is elliptical by design as in, for example, an IC-engine piston.Band-pass lterLow-pass lterUnltered50-500 upr15-500 upr15-150 upr500 upr150 upr50 uprA circle is tted to the measured prole such that the sum of the squares of the departure of the prole data from this circle is a minimum. The roundness gure is then dened as the difference between the maximum deviation of the prole from this circle (highest peak to the lowest valley).Two concentric circles are positioned to enclose the measured prole such that their radial difference is a minimum. The roundness gure is then dened as the radial separation of these two circles.The smallest circle that can enclose the measured prole is created. The roundness gure is then dened as the maximum deviation of the prole from this circle. This circle is sometimes referred to as the ‘ring gage’ circle.The largest circle that can be enclosed by the prole data is created. The roundness gure is then dened as the maximum deviation of the prole from this circle. This circle is sometimes referred to as the `plug gage' circle.ΔZq = Rmax-RminΔZq : A symbol indicating roundness value by LSC.ΔZz = Rmax-RminΔºZz : A symbol indicating roundness value by MZC.ΔZi = Rmax-RminΔZi : A symbol indicating roundness value by MIC. ΔZc = Rmax-RminΔºZc : A symbol indicating roundness value by MCC.Least Square Circle(LSC)Minimum Zone Circles(MZC)Minimum CircumscribedCircle (MCC)Maximum inscribedCircle (MIC)RmaxRminRmaxRminRmaxRminRmaxRmin

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