ASME B89.7.3.3:2003 pdf free download

ASME B89.7.3.3:2003 pdf free download.GUIDELINES FOR ASSESSING THE RELIABILITYOF DIMENSIONAL MEASUREMENT UNCERTAINTY STATEMENTS.
The primary purpose of this technical report is to provide guidelines for assessing the reliability of measurement uncertainty statements. Applying these guidelines can assist businesses in avoiding disagreements about measurement uncertainty statements and in resolv-
ing such disagreements should they nccur. Disagreements over uncertainty statements involving hoth single measurement systems and multiple measurement systems (each having their own uncertainty statement) are considered. Guidance is provided for cxamining uncertainty budgets as the primary method of asessing their relibility. Additionally, resolution by direcl measurement of the measurand is also discussed.
1 SCOPE
1.1 Objective
This icchnical report provides guidance in asscssing the rcliability of a stalcmcnt of mcasurement uncertainty in qucstion, that is, in judging whether that stated uncertainty can be trusted to include the values that could reasonably be attributed to the measured quantity (measurand) with which that staled uncertainty is associated.
1.2 Applicabllity
This report is most applicablc to statements of unceruainty in the resuits of dimensional measurements based upon the ISO Guide 10 Expression of Unerainty in Measuremenl (GUM). (Also calied ANSI/NCSL Z540-2.)
1.3 Purpose
This technical report helps parties to avoid potential, or resolve actual, disagreements over the magnitude of a stated measurement uncertainty, particularly when that uncertainty is part of a determinatton of conformity of a manufactured product to a dimensional specification.
4.3 GUM Noncompliance and Uncorrected
Systematic Errors
The GUM provides a unified, consistent means for calculating mcasurenment unceriainiy. Failure io follow the proccdurcs described in the GUM may result in a substantially different uncertainty statement. Procedurcs for calculating measurement uncertainty are well described in the GUM, a nationally and intemationally recognized document. Deviations from this approach,
e.g. algcbraically summing unccrtainty componcnis, will lead to disagreements between uncertainty budgets and should be avoidd. Common ways of failing to comply with the GUM include not accounting for known systematic errors (GUM 3.2 and F.2.4.5) and not using the law of propagation of uncertainty (GUM 5.1.2) (or some other appropriate means of combining uncertainty sources such as computer simulation). While it is recommended that corections for all known systematic errors be applied to the measurement resul, in some cases this is economically undesirable; a discussion of the inclusion of uncorrected systematic erors in uncertainty statements can be found in Phillips, Eberhardt, and Parry.
4.4 Pooriy Reaiized or incompieteiy Defined Measurand
Mcasurement results and their uncertaintics are associated with a particular measurand. The numerical valuc associaled with some measurands may be time dependent; i.e.. the value realized by a measurement could change in uime due 10 degradation, temporal insuability.
wear, or damage. Two measurements separaled in time could realize [WO different values for a well-specified measurand. A common exaruple is damage to the product under consideraion (particularly in uransporl) which systematically changes the value associated with the measurand. (The measurand itself, which is a set of specications, remains unchanged, sce Phillips, Esler, et al. for a more extcnsive discussion of this issue.) One method of detecting this problem involves cxamining the consistency of repeated mcasurements scparated in time, e.g. before and after transport.
In order for mcasuremcnt rcsults and their associated measurement uncertaintics to be compared, they must be measuring the same quantity (the same measurand).