Early History of the Development and Characterization of a 50 mm Diameter, Gas-Operated Piston Gauge as a Primary Pressure Standard
P Delajoud, M Girard, Charles D. Ehrlich
The early history of the development and characterization of a set of three 50 mm diameter piston gauges for primary atmospheric-range pressure measurement is described including target geometric specifications and uncertainty objectives. Besides the relatively large diameter of the pistons and the cylinder bores, other noteworthy features of the piston gauges included pistons and cylinders made of a ceramic material, a floating cylinder design, and the ability to vary the gaps between each piston and cylinder combination through application of an independent pressure along a portion of the inner surface of the hollow piston. The piston and cylinder elements were measured dimensionally by the National Institute of Standards and Technology (NIST) and effective areas and associated uncertainties were calculated. The performance of the piston gauges was examined by comparisons amongst themselves and both mode-of-operation and gas species dependence of the effective areas were investigated. It was concluded that changes in the piston-cylinder materials were needed to make the systems easier to use consistently and reduce uncertainty. This early work demonstrated the potential of the approach. The project, with some hardware changes, remains ongoing.
piston gauge, pressure measurements, pressure standard
, Girard, M.
and Ehrlich, C.
Early History of the Development and Characterization of a 50 mm Diameter, Gas-Operated Piston Gauge as a Primary Pressure Standard, Metrologia
(Accessed June 4, 2023)