Characterization of dead weight testers and computation of associated uncertainties: a case study of contemporary techniques

• Autorzy: Yadav S.
• Języki publikacji: EN

Abstrakty

EN

Estimation of uncertainty associated with pressure, measured by a dead weight tester is a key issue of recent times in pressure metrology. Though two different techniques have been used in the past yet there has been little uniformity in the way in which the measurement uncertainties of dead weight piston testers are evaluated and expressed. One of the techniques described in EAL document follows the universal approach based on ISO Guide and the relatively recent approach described in the National Accreditation Board of Laboratories (NABL-141) document presents a method for evaluating uncertainty in pressure measurement using dead weight testers through statistical analysis and error evaluated through linear curve fitting. This method is though in line with ISO Guide on the expression of uncertainty in measurement but differs from the traditional uncertainty measurement computations. The present paper describes a comparative study of these two different approaches through a case study carried out on an industrial dual range simple type dead weight tester. The paper also highlights some of the facts: how the new estimates affect pressure measurement and their commercial implementation and the benefits over traditional estimates.

• Wydawca: Komitet Metrologii i Aparatury Naukowej PAN
• Czasopismo: Metrology and Measurement Systems
• Rocznik: 2007
• Tom: Vol. 14, nr 3
• Strony: 453--469
• Opis fizyczny: Bibliogr. 10 poz., rys., tab., wzory

Twórcy

autor

Yadav S.

• National Physical Laboratory, New Delhi,

Bibliografia

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