ASME B89.1.7:2009 pdf free download

ASME B89.1.7:2009 pdf free download.Performance Standard for Steel Measuring Tapes.
2 DEFINITIONS
accuracy: closeness of agreement between a measured quantity value and a true quantity valucof a mcasurand. Accuracy is a qualitative concept. (VIM 213)
grac1uatiori: marks or lines perpendicular to the edge of a measuring tape denoting increments of measure.
infrrnwdiak graduation: a graduation mark denoting an increment of measure that falls between the major and the minor graduations (e.g., inch or centimeter).
major graduation: a graduation mark denoting the largest increment of measure (e.g., feet or meter).
,riaxiinun permissible errors (MPE): extreme value of measurement error, with respect to a known reference quantity value, permitted by specifications or regulations for a given measurement, measuring instrument, or measuring system. (VIM 4.26)
rumor graduation: a graduation mark denoting the smallest increment of measure (e.g., fraction of an inch, decimal inch, or millimeter).
plumb bob: when used with a measuring tape, a weight with a tapered or flat tip on the bottom that is suspended from the tape.
tension: a force that tends to stretch or elongate something, or a measure of such a force.
NOTE; The measure of force in the U.S. Customary svsteni is the pound (Ibf); the measure of force in the SI system is the newton (N). Trad,iionalI the tension (a force) has been referred to in units of pounds and kilograms. Pound (or pound-force) is proper. In the SI system of units, the kilogram is the unit of mass and the newton is the unit of force. In this Standard, the tension for tapes graduated in SI units is specified in kilograms, in order to maintain continuity of reference to master tape calibration dMa. The corresponding force in newtons is equal to the applied mass in kilograms multiplied by the acceleratkm due to gravity. g. By convention, g = 9JlthtiS rn/s2 exactly. Thus, the force exerted on a tape by a I kg load is 9.80665 N. For highest accuracy, the local value of should be used.
vaiiditii conditions: the set of values or range of values of the relevant influence quantities, e.g., environmental conditions, under which the performance specifications are valid.
(c) Stale the expanded (k = 2) uncertainty associated with the calibrated distance of the reference standard as used at the time of measurement.
NOTE This includes both the uncertainty on the calibration cerhficatc and e1fccb such as the prevailing thermal conditions at the tinw of the calibration, and associated equipment used to tran.Ier the value from the master to the taEw under calibration, for esimpie. a mkrasco carriage system.
(d) Provide an uncertainty budget describing the uncertainty components used to compute the statement of uncertainty. For a master tape, the typical uncertainty components are the calibration uncertaint the uncertainty in the master tape temperature (used to make the nominal thermal expansion correction), and the uncertainty in the coefficient of thermal expansion of the master tape. Additional uncertainty components may include lixturing effects.
(e) Provide documentation of traceability back to an appropriate terminus of the standard used for the reference standard (see section 1-3 for an appropriate metro- logical terminus). For example, for a master tape the calibration certificate would suffice assuming the certificate is from an appropriate metrological terminus.
(fi Show evidence of an internal quality assurance program so that the measurement uncertainty statement for the reference standard is assured. This may be a simple procedure to ensure that the reference standard is periodically recalibrated; other sensors, e.g., the weather station of a reference interferometer, are periodically recalibrated; and the artifact fixturirtg or other effects are in accordance with the calibration requirements or otherwise taken into account in the uncertainty budget.
1-3 METROLOGICAI. TERMINUS
An appropriate metmiogical terminus for the documentation traceability is any one of the following sources (see ASMF. B89.7.5 for further details).