APX50, the first fully automatic absolute pressure balance in the range 10 kPa to 1 MPa

ISSN： 0026-1394

Source： Metrologia, Vol.36, Iss.6, 1999-12, pp. : 531-533

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

Desgranges et Huot, a French company specializing in pressure metrology, has been cooperating with the Bureau National de Metrologie-Laboratoire National d'Essais (BNM-LNE) for the past five years in the development of the first fully automatic absolute pressure balance in the range 10 kPa to 1 MPa, designated APX50. The different steps of this project are explained and the technical specifications and configuration of the APX50 are presented. A new measuring block has been developed, based on a rotating cylinder and receiving large effective area piston-cylinders. In addition, a very original mass-loading system has been created allowing the automatization of this operation down to the fractional 1 g mass. The new design concept of this system allows automatic absolute pressure measurements to be carried out with a relative uncertainty down to 5 x 10^-6. The complete metrological characteristics of the pressure balance are presented by the BNM-LNE elsewhere in this issue. This system, which offers the reliability and specifications of high-accuracy pressure balances together with unique features simplifying its operation, could potentially replace the mercury columns used as reference standards in national metrology institutes worldwide.