A Double-Primary Dead-Weight Tester for Pressures (35-175) kPa in Gage Mode

Published

February 1, 2003

Author(s)

K. Jain, Y Q. Cen, Walter J. Bowers Jr., James W. Schmidt

Abstract

Primary pressure standards in the atmospheric pressure range are often established using mercury manometers. Less frequently, controlled-clearance dead-weight testers in which one component (normally the piston) has been dimensionally measured have also been used. Recent advances in technology on two fronts i) the fabrication of large-diameter pistons and cylinders with good geometry; and ii) the ability to measure the dimensions of these components, have allowed some dead-weight testers at NIST to approach total relative uncertainties (2ς) in dimensionally-derived effective areas near 5 ppm. This paper descibes a single piston/cylinderassembly (NIST-PG201WC/WC) that serves as both a primary gage in which both piston and cylinder are measured dimensionally and a controlled-clearance primary gage (employing the Heydemann-Welch method). Thus it allows some previous assumptions about the modeling of dead-weight testers to be checked. For the gage described in this paper the effective areas obtained from the two analyses differ by 4 to 7 ppm over the pressure range 35 kPa to 175 k)a. Some implications of these results will be discussed.

Citation

Journal of Research (NIST JRES) -

Volume

108 No. 1

NIST Pub Series

Journal of Research (NIST JRES)

Pub Type

NIST Pubs

Keywords

dead-weight tester, piston gage, piston/cylinder assembly, pressure measurement, primary pressure standards

Citation

Jain, K. , Cen, Y. , Bowers Jr., W. and Schmidt, J. (2003), A Double-Primary Dead-Weight Tester for Pressures (35-175) kPa in Gage Mode, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed December 22, 2024)