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TitleA method of analysis for cross-floats between pressure balances
Publication TypeJournal Article
Year of Publication2005
AuthorsSutton, C.M., Fitzgerald M.P., and Giardini W.
PaginationS212 - S215
Date Published2005
ISSN00261394 (ISSN)
KeywordsCalibration, Cross-floats, Distortion coefficients, Elastic deformation, Least squares approximations, Plastic deformation, Precision balances, Pressure balances, PRESSURE MEASUREMENT, Surface tension
AbstractWe present a method of analysis for cross-floats between pressure balances. This analysis relates to the residual mass method of treating cross-float data in which the residual mass Me of one pressure balance is an unknown in the analysis, along with the effective area and the elastic distortion coefficient. Me is the effective mass of any unweighed parts of the piston and load and may include an equivalent mass for other forces on the piston such as oil surface tension. Two models for the analysis with the M e method are presented in a form suitable for linear least squares analysis: one for the calibration of a pressure balance and the other for the comparison of two reference pressure balances. This analysis is equivalent to the p-method when Me is known to be zero. Linear generalized least-squares estimation is shown to be convenient for the calculations. A pressure balance calibration is used to illustrate the analysis and the associated uncertainty evaluation. © 2005 BIPM and IOP Publishing Ltd.

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